1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2010 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 * Copyright 2018 Joyent, Inc. 25 * Copyright 2013 Nexenta Systems, Inc. All rights reserved. 26 * Copyright 2024 Oxide Computer Company 27 */ 28 29 /* 30 * MAC data path 31 * 32 * The MAC data path is concerned with the flow of traffic from mac clients -- 33 * DLS, IP, etc. -- to various GLDv3 device drivers -- e1000g, vnic, aggr, 34 * ixgbe, etc. -- and from the GLDv3 device drivers back to clients. 35 * 36 * ----------- 37 * Terminology 38 * ----------- 39 * 40 * MAC uses a lot of different, but related terms that are associated with the 41 * design and structure of the data path. Before we cover other aspects, first 42 * let's review the terminology that MAC uses. 43 * 44 * MAC 45 * 46 * This driver. It interfaces with device drivers and provides abstractions 47 * that the rest of the system consumes. All data links -- things managed 48 * with dladm(8), are accessed through MAC. 49 * 50 * GLDv3 DEVICE DRIVER 51 * 52 * A GLDv3 device driver refers to a driver, both for pseudo-devices and 53 * real devices, which implement the GLDv3 driver API. Common examples of 54 * these are igb and ixgbe, which are drivers for various Intel networking 55 * cards. These devices may or may not have various features, such as 56 * hardware rings and checksum offloading. For MAC, a GLDv3 device is the 57 * final point for the transmission of a packet and the starting point for 58 * the receipt of a packet. 59 * 60 * FLOWS 61 * 62 * At a high level, a flow refers to a series of packets that are related. 63 * Often times the term is used in the context of TCP to indicate a unique 64 * TCP connection and the traffic over it. However, a flow can exist at 65 * other levels of the system as well. MAC has a notion of a default flow 66 * which is used for all unicast traffic addressed to the address of a MAC 67 * device. For example, when a VNIC is created, a default flow is created 68 * for the VNIC's MAC address. In addition, flows are created for broadcast 69 * groups and a user may create a flow with flowadm(8). 70 * 71 * CLASSIFICATION 72 * 73 * Classification refers to the notion of identifying an incoming frame 74 * based on its destination address and optionally its source addresses and 75 * doing different processing based on that information. Classification can 76 * be done in both hardware and software. In general, we usually only 77 * classify based on the layer two destination, eg. for Ethernet, the 78 * destination MAC address. 79 * 80 * The system also will do classification based on layer three and layer 81 * four properties. This is used to support things like flowadm(8), which 82 * allows setting QoS and other properties on a per-flow basis. 83 * 84 * RING 85 * 86 * Conceptually, a ring represents a series of framed messages, often in a 87 * contiguous chunk of memory that acts as a circular buffer. Rings come in 88 * a couple of forms. Generally they are either a hardware construct (hw 89 * ring) or they are a software construct (sw ring) maintained by MAC. 90 * 91 * HW RING 92 * 93 * A hardware ring is a set of resources provided by a GLDv3 device driver 94 * (even if it is a pseudo-device). A hardware ring comes in two different 95 * forms: receive (rx) rings and transmit (tx) rings. An rx hw ring is 96 * something that has a unique DMA (direct memory access) region and 97 * generally supports some form of classification (though it isn't always 98 * used), as well as a means of generating an interrupt specific to that 99 * ring. For example, the device may generate a specific MSI-X for a PCI 100 * express device. A tx ring is similar, except that it is dedicated to 101 * transmission. It may also be a vector for enabling features such as VLAN 102 * tagging and large transmit offloading. It usually has its own dedicated 103 * interrupts for transmit being completed. 104 * 105 * SW RING 106 * 107 * A software ring is a construction of MAC. It represents the same thing 108 * that a hardware ring generally does, a collection of frames. However, 109 * instead of being in a contiguous ring of memory, they're instead linked 110 * by using the mblk_t's b_next pointer. Each frame may itself be multiple 111 * mblk_t's linked together by the b_cont pointer. A software ring always 112 * represents a collection of classified packets; however, it varies as to 113 * whether it uses only layer two information, or a combination of that and 114 * additional layer three and layer four data. 115 * 116 * FANOUT 117 * 118 * Fanout is the idea of spreading out the load of processing frames based 119 * on the source and destination information contained in the layer two, 120 * three, and four headers, such that the data can then be processed in 121 * parallel using multiple hardware threads. 122 * 123 * A fanout algorithm hashes the headers and uses that to place different 124 * flows into a bucket. The most important thing is that packets that are 125 * in the same flow end up in the same bucket. If they do not, performance 126 * can be adversely affected. Consider the case of TCP. TCP severely 127 * penalizes a connection if the data arrives out of order. If a given flow 128 * is processed on different CPUs, then the data will appear out of order, 129 * hence the invariant that fanout always hash a given flow to the same 130 * bucket and thus get processed on the same CPU. 131 * 132 * RECEIVE SIDE SCALING (RSS) 133 * 134 * 135 * Receive side scaling is a term that isn't common in illumos, but is used 136 * by vendors and was popularized by Microsoft. It refers to the idea of 137 * spreading the incoming receive load out across multiple interrupts which 138 * can be directed to different CPUs. This allows a device to leverage 139 * hardware rings even when it doesn't support hardware classification. The 140 * hardware uses an algorithm to perform fanout that ensures the flow 141 * invariant is maintained. 142 * 143 * SOFT RING SET 144 * 145 * A soft ring set, commonly abbreviated SRS, is a collection of rings and 146 * is used for both transmitting and receiving. It is maintained in the 147 * structure mac_soft_ring_set_t. A soft ring set is usually associated 148 * with flows, and coordinates both the use of hardware and software rings. 149 * Because the use of hardware rings can change as devices such as VNICs 150 * come and go, we always ensure that the set has software classification 151 * rules that correspond to the hardware classification rules from rings. 152 * 153 * Soft ring sets are also used for the enforcement of various QoS 154 * properties. For example, if a bandwidth limit has been placed on a 155 * specific flow or device, then that will be enforced by the soft ring 156 * set. 157 * 158 * SERVICE ATTACHMENT POINT (SAP) 159 * 160 * The service attachment point is a DLPI (Data Link Provider Interface) 161 * concept; however, it comes up quite often in MAC. Most MAC devices speak 162 * a protocol that has some notion of different channels or message type 163 * identifiers. For example, Ethernet defines an EtherType which is a part 164 * of the Ethernet header and defines the particular protocol of the data 165 * payload. If the EtherType is set to 0x0800, then it defines that the 166 * contents of that Ethernet frame is IPv4 traffic. For Ethernet, the 167 * EtherType is the SAP. 168 * 169 * In DLPI, a given consumer attaches to a specific SAP. In illumos, the ip 170 * and arp drivers attach to the EtherTypes for IPv4, IPv6, and ARP. Using 171 * libdlpi(3LIB) user software can attach to arbitrary SAPs. With the 172 * exception of 802.1Q VLAN tagged traffic, MAC itself does not directly 173 * consume the SAP; however, it uses that information as part of hashing 174 * and it may be used as part of the construction of flows. 175 * 176 * PRIMARY MAC CLIENT 177 * 178 * The primary mac client refers to a mac client whose unicast address 179 * matches the address of the device itself. For example, if the system has 180 * instance of the e1000g driver such as e1000g0, e1000g1, etc., the 181 * primary mac client is the one named after the device itself. VNICs that 182 * are created on top of such devices are not the primary client. 183 * 184 * TRANSMIT DESCRIPTORS 185 * 186 * Transmit descriptors are a resource that most GLDv3 device drivers have. 187 * Generally, a GLDv3 device driver takes a frame that's meant to be output 188 * and puts a copy of it into a region of memory. Each region of memory 189 * usually has an associated descriptor that the device uses to manage 190 * properties of the frames. Devices have a limited number of such 191 * descriptors. They get reclaimed once the device finishes putting the 192 * frame on the wire. 193 * 194 * If the driver runs out of transmit descriptors, for example, the OS is 195 * generating more frames than it can put on the wire, then it will return 196 * them back to the MAC layer. 197 * 198 * --------------------------------- 199 * Rings, Classification, and Fanout 200 * --------------------------------- 201 * 202 * The heart of MAC is made up of rings, and not those that Elven-kings wear. 203 * When receiving a packet, MAC breaks the work into two different, though 204 * interrelated phases. The first phase is generally classification and then the 205 * second phase is generally fanout. When a frame comes in from a GLDv3 Device, 206 * MAC needs to determine where that frame should be delivered. If it's a 207 * unicast frame (say a normal TCP/IP packet), then it will be delivered to a 208 * single MAC client; however, if it's a broadcast or multicast frame, then MAC 209 * may need to deliver it to multiple MAC clients. 210 * 211 * On transmit, classification isn't quite as important, but may still be used. 212 * Unlike with the receive path, the classification is not used to determine 213 * devices that should transmit something, but rather is used for special 214 * properties of a flow, eg. bandwidth limits for a given IP address, device, or 215 * connection. 216 * 217 * MAC employs a software classifier and leverages hardware classification as 218 * well. The software classifier can leverage the full layer two information, 219 * source, destination, VLAN, and SAP. If the SAP indicates that IP traffic is 220 * being sent, it can classify based on the IP header, and finally, it also 221 * knows how to classify based on the local and remote ports of TCP, UDP, and 222 * SCTP. 223 * 224 * Hardware classifiers vary in capability. Generally all hardware classifiers 225 * provide the capability to classify based on the destination MAC address. Some 226 * hardware has additional filters built in for performing more in-depth 227 * classification; however, it often has much more limited resources for these 228 * activities as compared to the layer two destination address classification. 229 * 230 * The modus operandi in MAC is to always ensure that we have software-based 231 * capabilities and rules in place and then to supplement that with hardware 232 * resources when available. In general, simple layer two classification is 233 * sufficient and nothing else is used, unless a specific flow is created with 234 * tools such as flowadm(8) or bandwidth limits are set on a device with 235 * dladm(8). 236 * 237 * RINGS AND GROUPS 238 * 239 * To get into how rings and classification play together, it's first important 240 * to understand how hardware devices commonly associate rings and allow them to 241 * be programmed. Recall that a hardware ring should be thought of as a DMA 242 * buffer and an interrupt resource. Rings are then collected into groups. A 243 * group itself has a series of classification rules. One or more MAC addresses 244 * are assigned to a group. 245 * 246 * Hardware devices vary in terms of what capabilities they provide. Sometimes 247 * they allow for a dynamic assignment of rings to a group and sometimes they 248 * have a static assignment of rings to a group. For example, the ixgbe driver 249 * has a static assignment of rings to groups such that every group has exactly 250 * one ring and the number of groups is equal to the number of rings. 251 * 252 * Classification and receive side scaling both come into play with how a device 253 * advertises itself to MAC and how MAC uses it. If a device supports layer two 254 * classification of frames, then MAC will assign MAC addresses to a group as a 255 * form of primary classification. If a single MAC address is assigned to a 256 * group, a common case, then MAC will consider packets that come in from rings 257 * on that group to be fully classified and will not need to do any software 258 * classification unless a specific flow has been created. 259 * 260 * If a device supports receive side scaling, then it may advertise or support 261 * groups with multiple rings. In those cases, then receive side scaling will 262 * come into play and MAC will use that as a means of fanning out received 263 * frames across multiple CPUs. This can also be combined with groups that 264 * support layer two classification. 265 * 266 * If a device supports dynamic assignments of rings to groups, then MAC will 267 * change around the way that rings are assigned to various groups as devices 268 * come and go from the system. For example, when a VNIC is created, a new flow 269 * will be created for the VNIC's MAC address. If a hardware ring is available, 270 * MAC may opt to reassign it from one group to another. 271 * 272 * ASSIGNMENT OF HARDWARE RINGS 273 * 274 * This is a bit of a complicated subject that varies depending on the device, 275 * the use of aggregations, the special nature of the primary mac client. This 276 * section deserves being fleshed out. 277 * 278 * FANOUT 279 * 280 * illumos uses fanout to help spread out the incoming processing load of chains 281 * of frames away from a single CPU. If a device supports receive side scaling, 282 * then that provides an initial form of fanout; however, what we're concerned 283 * with all happens after the context of a given set of frames being classified 284 * to a soft ring set. 285 * 286 * After frames reach a soft ring set and account for any potential bandwidth 287 * related accounting, they may be fanned out based on one of the following 288 * three modes: 289 * 290 * o No Fanout 291 * o Protocol level fanout 292 * o Full software ring protocol fanout 293 * 294 * MAC makes the determination as to which of these modes a given soft ring set 295 * obtains based on parameters such as whether or not it's the primary mac 296 * client, whether it's on a 10 GbE or faster device, user controlled dladm(8) 297 * properties, and the nature of the hardware and the resources that it has. 298 * 299 * When there is no fanout, MAC does not create any soft rings for a device and 300 * the device has frames delivered directly to the MAC client. 301 * 302 * Otherwise, all fanout is performed by software. MAC divides incoming frames 303 * into one of three buckets -- IPv4 TCP traffic, IPv4 UDP traffic, and 304 * everything else. Regardless of the type of fanout, these three categories 305 * or buckets are always used. 306 * 307 * The difference between protocol level fanout and full software ring protocol 308 * fanout is the number of software rings that end up getting created. The 309 * system always uses the same number of software rings per protocol bucket. So 310 * in the first case when we're just doing protocol level fanout, we just create 311 * one software ring each for IPv4 TCP traffic, IPv4 UDP traffic, and everything 312 * else. 313 * 314 * In the case where we do full software ring protocol fanout, we generally use 315 * mac_compute_soft_ring_count() to determine the number of rings. There are 316 * other combinations of properties and devices that may send us down other 317 * paths, but this is a common starting point. If it's a non-bandwidth enforced 318 * device and we're on at least a 10 GbE link, then we'll use eight soft rings 319 * per protocol bucket as a starting point. See mac_compute_soft_ring_count() 320 * for more information on the total number. 321 * 322 * For each of these rings, we create a mac_soft_ring_t and an associated worker 323 * thread. Particularly when doing full software ring protocol fanout, we bind 324 * each of the worker threads to individual CPUs. 325 * 326 * The other advantage of these software rings is that it allows upper layers to 327 * optionally poll on them. For example, TCP can leverage an squeue to poll on 328 * the software ring, see squeue.c for more information. 329 * 330 * DLS BYPASS 331 * 332 * DLS is the data link services module. It interfaces with DLPI, which is the 333 * primary way that other parts of the system such as IP interface with the MAC 334 * layer. While DLS is traditionally a STREAMS-based interface, it allows for 335 * certain modules such as IP to negotiate various more modern interfaces to be 336 * used, which are useful for higher performance and allow it to use direct 337 * function calls to DLS instead of using STREAMS. 338 * 339 * When we have IPv4 TCP or UDP software rings, then traffic on those rings is 340 * eligible for what we call the dls bypass. In those cases, rather than going 341 * out mac_rx_deliver() to DLS, DLS instead registers them to go directly via 342 * the direct callback registered with DLS, generally ip_input(). 343 * 344 * HARDWARE RING POLLING 345 * 346 * GLDv3 devices with hardware rings generally deliver chains of messages 347 * (mblk_t chain) during the context of a single interrupt. However, interrupts 348 * are not the only way that these devices may be used. As part of implementing 349 * ring support, a GLDv3 device driver must have a way to disable the generation 350 * of that interrupt and allow for the operating system to poll on that ring. 351 * 352 * To implement this, every soft ring set has a worker thread and a polling 353 * thread. If a sufficient packet rate comes into the system, MAC will 'blank' 354 * (disable) interrupts on that specific ring and the polling thread will start 355 * consuming packets from the hardware device and deliver them to the soft ring 356 * set, where the worker thread will take over. 357 * 358 * Once the rate of packet intake drops down below a certain threshold, then 359 * polling on the hardware ring will be quiesced and interrupts will be 360 * re-enabled for the given ring. This effectively allows the system to shift 361 * how it handles a ring based on its load. At high packet rates, polling on the 362 * device as opposed to relying on interrupts can actually reduce overall system 363 * load due to the minimization of interrupt activity. 364 * 365 * Note the importance of each ring having its own interrupt source. The whole 366 * idea here is that we do not disable interrupts on the device as a whole, but 367 * rather each ring can be independently toggled. 368 * 369 * USE OF WORKER THREADS 370 * 371 * Both the soft ring set and individual soft rings have a worker thread 372 * associated with them that may be bound to a specific CPU in the system. Any 373 * such assignment will get reassessed as part of dynamic reconfiguration events 374 * in the system such as the onlining and offlining of CPUs and the creation of 375 * CPU partitions. 376 * 377 * In many cases, while in an interrupt, we try to deliver a frame all the way 378 * through the stack in the context of the interrupt itself. However, if the 379 * amount of queued frames has exceeded a threshold, then we instead defer to 380 * the worker thread to do this work and signal it. This is particularly useful 381 * when you have the soft ring set delivering frames into multiple software 382 * rings. If it was only delivering frames into a single software ring then 383 * there'd be no need to have another thread take over. However, if it's 384 * delivering chains of frames to multiple rings, then it's worthwhile to have 385 * the worker for the software ring take over so that the different software 386 * rings can be processed in parallel. 387 * 388 * In a similar fashion to the hardware polling thread, if we don't have a 389 * backlog or there's nothing to do, then the worker thread will go back to 390 * sleep and frames can be delivered all the way from an interrupt. This 391 * behavior is useful as it's designed to minimize latency and the default 392 * disposition of MAC is to optimize for latency. 393 * 394 * MAINTAINING CHAINS 395 * 396 * Another useful idea that MAC uses is to try and maintain frames in chains for 397 * as long as possible. The idea is that all of MAC can handle chains of frames 398 * structured as a series of mblk_t structures linked with the b_next pointer. 399 * When performing software classification and software fanout, MAC does not 400 * simply determine the destination and send the frame along. Instead, in the 401 * case of classification, it tries to maintain a chain for as long as possible 402 * before passing it along and performing additional processing. 403 * 404 * In the case of fanout, MAC first determines what the target software ring is 405 * for every frame in the original chain and constructs a new chain for each 406 * target. MAC then delivers the new chain to each software ring in succession. 407 * 408 * The whole rationale for doing this is that we want to try and maintain the 409 * pipe as much as possible and deliver as many frames through the stack at once 410 * that we can, rather than just pushing a single frame through. This can often 411 * help bring down latency and allows MAC to get a better sense of the overall 412 * activity in the system and properly engage worker threads. 413 * 414 * -------------------- 415 * Bandwidth Management 416 * -------------------- 417 * 418 * Bandwidth management is something that's built into the soft ring set itself. 419 * When bandwidth limits are placed on a flow, a corresponding soft ring set is 420 * toggled into bandwidth mode. This changes how we transmit and receive the 421 * frames in question. 422 * 423 * Bandwidth management is done on a per-tick basis. We translate the user's 424 * requested bandwidth from a quantity per-second into a quantity per-tick. MAC 425 * cannot process a frame across more than one tick, thus it sets a lower bound 426 * for the bandwidth cap to be a single MTU. This also means that when 427 * hires ticks are enabled (hz is set to 1000), that the minimum amount of 428 * bandwidth is higher, because the number of ticks has increased and MAC has to 429 * go from accepting 100 packets / sec to 1000 / sec. 430 * 431 * The bandwidth counter is reset by either the soft ring set's worker thread or 432 * a thread that is doing an inline transmit or receive if they discover that 433 * the current tick is in the future from the recorded tick. 434 * 435 * Whenever we're receiving or transmitting data, we end up leaving most of the 436 * work to the soft ring set's worker thread. This forces data inserted into the 437 * soft ring set to be effectively serialized and allows us to exhume bandwidth 438 * at a reasonable rate. If there is nothing in the soft ring set at the moment 439 * and the set has available bandwidth, then it may processed inline. 440 * Otherwise, the worker is responsible for taking care of the soft ring set. 441 * 442 * --------------------- 443 * The Receive Data Path 444 * --------------------- 445 * 446 * The following series of ASCII art images breaks apart the way that a frame 447 * comes in and is processed in MAC. 448 * 449 * Part 1 -- Initial frame receipt, SRS classification 450 * 451 * Here, a frame is received by a GLDv3 driver, generally in the context of an 452 * interrupt, and it ends up in mac_rx_common(). A driver calls either mac_rx or 453 * mac_rx_ring, depending on whether or not it supports rings and can identify 454 * the interrupt as having come from a specific ring. Here we determine whether 455 * or not it's fully classified and perform software classification as 456 * appropriate. From here, everything always ends up going to either entry [A] 457 * or entry [B] based on whether or not they have subflow processing needed. We 458 * leave via fanout or delivery. 459 * 460 * +===========+ 461 * v hardware v 462 * v interrupt v 463 * +===========+ 464 * | 465 * * . . appropriate 466 * | upcall made 467 * | by GLDv3 driver . . always 468 * | . 469 * +--------+ | +----------+ . +---------------+ 470 * | GLDv3 | +---->| mac_rx |-----*--->| mac_rx_common | 471 * | Driver |-->--+ +----------+ +---------------+ 472 * +--------+ | ^ | 473 * | | ^ v 474 * ^ | * . . always +----------------------+ 475 * | | | | mac_promisc_dispatch | 476 * | | +-------------+ +----------------------+ 477 * | +--->| mac_rx_ring | | 478 * | +-------------+ * . . hw classified 479 * | v or single flow? 480 * | | 481 * | +--------++--------------+ 482 * | | | * hw class, 483 * | | * hw classified | subflows 484 * | no hw class and . * | or single | exist 485 * | subflows | | flow | 486 * | | v v 487 * | | +-----------+ +-----------+ 488 * | | | goto | | goto | 489 * | | | entry [A] | | entry [B] | 490 * | | +-----------+ +-----------+ 491 * | v ^ 492 * | +-------------+ | 493 * | | mac_rx_flow | * SRS and flow found, 494 * | +-------------+ | call flow cb 495 * | | +------+ 496 * | v | 497 * v +==========+ +-----------------+ 498 * | v For each v--->| mac_rx_classify | 499 * +----------+ v mblk_t v +-----------------+ 500 * | srs | +==========+ 501 * | pollling | 502 * | thread |->------------------------------------------+ 503 * +----------+ | 504 * v . inline 505 * +--------------------+ +----------+ +---------+ . 506 * [A]---->| mac_rx_srs_process |-->| check bw |-->| enqueue |--*---------+ 507 * +--------------------+ | limits | | frames | | 508 * ^ +----------+ | to SRS | | 509 * | +---------+ | 510 * | send chain +--------+ | | 511 * * when clasified | signal | * BW limits, | 512 * | flow changes | srs |<---+ loopback, | 513 * | | worker | stack too | 514 * | +--------+ deep | 515 * +-----------------+ +--------+ | 516 * | mac_flow_lookup | | srs | +---------------------+ | 517 * +-----------------+ | worker |---->| mac_rx_srs_drain |<---+ 518 * ^ | thread | | mac_rx_srs_drain_bw | 519 * | +--------+ +---------------------+ 520 * | | 521 * +----------------------------+ * software rings 522 * [B]-->| mac_rx_srs_subflow_process | | for fanout? 523 * +----------------------------+ | 524 * +----------+-----------+ 525 * | | 526 * v v 527 * +--------+ +--------+ 528 * | goto | | goto | 529 * | Part 2 | | Part 3 | 530 * +--------+ +--------+ 531 * 532 * Part 2 -- Fanout 533 * 534 * This part is concerned with using software fanout to assign frames to 535 * software rings and then deliver them to MAC clients or allow those rings to 536 * be polled upon. While there are two different primary fanout entry points, 537 * mac_rx_fanout and mac_rx_proto_fanout, they behave in similar ways, and aside 538 * from some of the individual hashing techniques used, most of the general 539 * flow is the same. 540 * 541 * +--------+ +-------------------+ 542 * | From |---+--------->| mac_rx_srs_fanout |----+ 543 * | Part 1 | | +-------------------+ | +=================+ 544 * +--------+ | | v for each mblk_t v 545 * * . . protocol only +--->v assign to new v 546 * | fanout | v chain based on v 547 * | | v hash % nrings v 548 * | +-------------------------+ | +=================+ 549 * +--->| mac_rx_srs_proto_fanout |----+ | 550 * +-------------------------+ | 551 * v 552 * +------------+ +--------------------------+ +================+ 553 * | enqueue in |<---| mac_rx_soft_ring_process |<------v for each chain v 554 * | soft ring | +--------------------------+ +================+ 555 * +------------+ 556 * | +-----------+ 557 * * soft ring set | soft ring | 558 * | empty and no | worker | 559 * | worker? | thread | 560 * | +-----------+ 561 * +------*----------------+ | 562 * | . | v 563 * No . * . Yes | +------------------------+ 564 * | +----<--| mac_rx_soft_ring_drain | 565 * | | +------------------------+ 566 * v | 567 * +-----------+ v 568 * | signal | +---------------+ 569 * | soft ring | | Deliver chain | 570 * | worker | | goto Part 3 | 571 * +-----------+ +---------------+ 572 * 573 * 574 * Part 3 -- Packet Delivery 575 * 576 * Here, we go through and deliver the mblk_t chain directly to a given 577 * processing function. In a lot of cases this is mac_rx_deliver(). In the case 578 * of DLS bypass being used, then instead we end up going ahead and deliver it 579 * to the direct callback registered with DLS, generally ip_input. 580 * 581 * 582 * +---------+ +----------------+ +------------------+ 583 * | From |---+------->| mac_rx_deliver |--->| Off to DLS, or | 584 * | Parts 1 | | +----------------+ | other MAC client | 585 * | and 2 | * DLS bypass +------------------+ 586 * +---------+ | enabled +----------+ +-------------+ 587 * +---------->| ip_input |--->| To IP | 588 * +----------+ | and beyond! | 589 * +-------------+ 590 * 591 * ---------------------- 592 * The Transmit Data Path 593 * ---------------------- 594 * 595 * Before we go into the images, it's worth talking about a problem that is a 596 * bit different from the receive data path. GLDv3 device drivers have a finite 597 * amount of transmit descriptors. When they run out, they return unused frames 598 * back to MAC. MAC, at this point has several options about what it will do, 599 * which vary based upon the settings that the client uses. 600 * 601 * When a device runs out of descriptors, the next thing that MAC does is 602 * enqueue them off of the soft ring set or a software ring, depending on the 603 * configuration of the soft ring set. MAC will enqueue up to a high watermark 604 * of mblk_t chains, at which point it will indicate flow control back to the 605 * client. Once this condition is reached, any mblk_t chains that were not 606 * enqueued will be returned to the caller and they will have to decide what to 607 * do with them. There are various flags that control this behavior that a 608 * client may pass, which are discussed below. 609 * 610 * When this condition is hit, MAC also returns a cookie to the client in 611 * addition to unconsumed frames. Clients can poll on that cookie and register a 612 * callback with MAC to be notified when they are no longer subject to flow 613 * control, at which point they may continue to call mac_tx(). This flow control 614 * actually manages to work itself all the way up the stack, back through dls, 615 * to ip, through the various protocols, and to sockfs. 616 * 617 * While the behavior described above is the default, this behavior can be 618 * modified. There are two alternate modes, described below, which are 619 * controlled with flags. 620 * 621 * DROP MODE 622 * 623 * This mode is controlled by having the client pass the MAC_DROP_ON_NO_DESC 624 * flag. When this is passed, if a device driver runs out of transmit 625 * descriptors, then the MAC layer will drop any unsent traffic. The client in 626 * this case will never have any frames returned to it. 627 * 628 * DON'T ENQUEUE 629 * 630 * This mode is controlled by having the client pass the MAC_TX_NO_ENQUEUE flag. 631 * If the MAC_DROP_ON_NO_DESC flag is also passed, it takes precedence. In this 632 * mode, when we hit a case where a driver runs out of transmit descriptors, 633 * then instead of enqueuing packets in a soft ring set or software ring, we 634 * instead return the mblk_t chain back to the caller and immediately put the 635 * soft ring set into flow control mode. 636 * 637 * The following series of ASCII art images describe the transmit data path that 638 * MAC clients enter into based on calling into mac_tx(). A soft ring set has a 639 * transmission function associated with it. There are seven possible 640 * transmission modes, some of which share function entry points. The one that a 641 * soft ring set gets depends on properties such as whether there are 642 * transmission rings for fanout, whether the device involves aggregations, 643 * whether any bandwidth limits exist, etc. 644 * 645 * 646 * Part 1 -- Initial checks 647 * 648 * * . called by 649 * | MAC clients 650 * v . . No 651 * +--------+ +-----------+ . +-------------------+ +====================+ 652 * | mac_tx |->| device |-*-->| mac_protect_check |->v Is this the simple v 653 * +--------+ | quiesced? | +-------------------+ v case? See [1] v 654 * +-----------+ | +====================+ 655 * * . Yes * failed | 656 * v | frames | 657 * +--------------+ | +-------+---------+ 658 * | freemsgchain |<---------+ Yes . * No . * 659 * +--------------+ v v 660 * +-----------+ +--------+ 661 * | goto | | goto | 662 * | Part 2 | | SRS TX | 663 * | Entry [A] | | func | 664 * +-----------+ +--------+ 665 * | | 666 * | v 667 * | +--------+ 668 * +---------->| return | 669 * | cookie | 670 * +--------+ 671 * 672 * [1] The simple case refers to the SRS being configured with the 673 * SRS_TX_DEFAULT transmission mode, having a single mblk_t (not a chain), their 674 * being only a single active client, and not having a backlog in the srs. 675 * 676 * 677 * Part 2 -- The SRS transmission functions 678 * 679 * This part is a bit more complicated. The different transmission paths often 680 * leverage one another. In this case, we'll draw out the more common ones 681 * before the parts that depend upon them. Here, we're going to start with the 682 * workings of mac_tx_send() a common function that most of the others end up 683 * calling. 684 * 685 * +-------------+ 686 * | mac_tx_send | 687 * +-------------+ 688 * | 689 * v 690 * +=============+ +==============+ 691 * v more than v--->v check v 692 * v one client? v v VLAN and add v 693 * +=============+ v VLAN tags v 694 * | +==============+ 695 * | | 696 * +------------------+ 697 * | 698 * | [A] 699 * v | 700 * +============+ . No v 701 * v more than v . +==========+ +--------------------------+ 702 * v one active v-*---->v for each v---->| mac_promisc_dispatch_one |---+ 703 * v client? v v mblk_t v +--------------------------+ | 704 * +============+ +==========+ ^ | 705 * | | +==========+ | 706 * * . Yes | v hardware v<-------+ 707 * v +------------+ v rings? v 708 * +==========+ | +==========+ 709 * v for each v No . . . * | 710 * v mblk_t v specific | | 711 * +==========+ flow | +-----+-----+ 712 * | | | | 713 * v | v v 714 * +-----------------+ | +-------+ +---------+ 715 * | mac_tx_classify |------------+ | GLDv3 | | GLDv3 | 716 * +-----------------+ |TX func| | ring tx | 717 * | +-------+ | func | 718 * * Specific flow, generally | +---------+ 719 * | bcast, mcast, loopback | | 720 * v +-----+-----+ 721 * +==========+ +---------+ | 722 * v valid L2 v--*--->| freemsg | v 723 * v header v . No +---------+ +-------------------+ 724 * +==========+ | return unconsumed | 725 * * . Yes | frames to the | 726 * v | caller | 727 * +===========+ +-------------------+ 728 * v braodcast v +----------------+ ^ 729 * v flow? v--*-->| mac_bcast_send |------------------+ 730 * +===========+ . +----------------+ | 731 * | . . Yes | 732 * No . * v 733 * | +---------------------+ +---------------+ +----------+ 734 * +->|mac_promisc_dispatch |->| mac_fix_cksum |->| flow | 735 * +---------------------+ +---------------+ | callback | 736 * +----------+ 737 * 738 * 739 * In addition, many but not all of the routines, all rely on 740 * mac_tx_softring_process as an entry point. 741 * 742 * 743 * . No . No 744 * +--------------------------+ +========+ . +===========+ . +-------------+ 745 * | mac_tx_soft_ring_process |-->v worker v-*->v out of tx v-*->| goto | 746 * +--------------------------+ v only? v v descr.? v | mac_tx_send | 747 * +========+ +===========+ +-------------+ 748 * Yes . * * . Yes | 749 * . No v | v 750 * v=========+ . +===========+ . Yes | Yes . +==========+ 751 * v apppend v<--*----------v out of tx v-*-------+---------*--v returned v 752 * v mblk_t v v descr.? v | v frames? v 753 * v chain v +===========+ | +==========+ 754 * +=========+ | *. No 755 * | | v 756 * v v +------------+ 757 * +===================+ +----------------------+ | done | 758 * v worker scheduled? v | mac_tx_sring_enqueue | | processing | 759 * v Out of tx descr? v +----------------------+ +------------+ 760 * +===================+ | 761 * | | . Yes v 762 * * Yes * No . +============+ 763 * | v +-*---------v drop on no v 764 * | +========+ v v TX desc? v 765 * | v wake v +----------+ +============+ 766 * | v worker v | mac_pkt_ | * . No 767 * | +========+ | drop | | . Yes . No 768 * | | +----------+ v . . 769 * | | v ^ +===============+ . +========+ . 770 * +--+--------+---------+ | v Don't enqueue v-*->v ring v-*----+ 771 * | | v Set? v v empty? v | 772 * | +---------------+ +===============+ +========+ | 773 * | | | | | 774 * | | +-------------------+ | | 775 * | *. Yes | +---------+ | 776 * | | v v v 777 * | | +===========+ +========+ +--------------+ 778 * | +<-v At hiwat? v v append v | return | 779 * | +===========+ v mblk_t v | mblk_t chain | 780 * | * No v chain v | and flow | 781 * | v +========+ | control | 782 * | +=========+ | | cookie | 783 * | v append v v +--------------+ 784 * | v mblk_t v +========+ 785 * | v chain v v wake v +------------+ 786 * | +=========+ v worker v-->| done | 787 * | | +========+ | processing | 788 * | v .. Yes +------------+ 789 * | +=========+ . +========+ 790 * | v first v--*-->v wake v 791 * | v append? v v worker v 792 * | +=========+ +========+ 793 * | | | 794 * | No . * | 795 * | v | 796 * | +--------------+ | 797 * +------>| Return | | 798 * | flow control |<------------+ 799 * | cookie | 800 * +--------------+ 801 * 802 * 803 * The remaining images are all specific to each of the different transmission 804 * modes. 805 * 806 * SRS TX DEFAULT 807 * 808 * [ From Part 1 ] 809 * | 810 * v 811 * +-------------------------+ 812 * | mac_tx_single_ring_mode | 813 * +-------------------------+ 814 * | 815 * | . Yes 816 * v . 817 * +==========+ . +============+ 818 * v SRS v-*->v Try to v---->---------------------+ 819 * v backlog? v v enqueue in v | 820 * +==========+ v SRS v-->------+ * . . Queue too 821 * | +============+ * don't enqueue | deep or 822 * * . No ^ | | flag or at | drop flag 823 * | | v | hiwat, | 824 * v | | | return +---------+ 825 * +-------------+ | | | cookie | freemsg | 826 * | goto |-*-----+ | | +---------+ 827 * | mac_tx_send | . returned | | | 828 * +-------------+ mblk_t | | | 829 * | | | | 830 * | | | | 831 * * . . all mblk_t * queued, | | 832 * v consumed | may return | | 833 * +-------------+ | tx cookie | | 834 * | SRS TX func |<------------+------------+----------------+ 835 * | completed | 836 * +-------------+ 837 * 838 * SRS_TX_SERIALIZE 839 * 840 * +------------------------+ 841 * | mac_tx_serializer_mode | 842 * +------------------------+ 843 * | 844 * | . No 845 * v . 846 * +============+ . +============+ +-------------+ +============+ 847 * v srs being v-*->v set SRS v--->| goto |-->v remove SRS v 848 * v processed? v v proc flags v | mac_tx_send | v proc flag v 849 * +============+ +============+ +-------------+ +============+ 850 * | | 851 * * Yes | 852 * v . No v 853 * +--------------------+ . +==========+ 854 * | mac_tx_srs_enqueue | +------------------------*-----<--v returned v 855 * +--------------------+ | v frames? v 856 * | | . Yes +==========+ 857 * | | . | 858 * | | . +=========+ v 859 * v +-<-*-v queued v +--------------------+ 860 * +-------------+ | v frames? v<----| mac_tx_srs_enqueue | 861 * | SRS TX func | | +=========+ +--------------------+ 862 * | completed, |<------+ * . Yes 863 * | may return | | v 864 * | cookie | | +========+ 865 * +-------------+ +-<---v wake v 866 * v worker v 867 * +========+ 868 * 869 * 870 * SRS_TX_FANOUT 871 * 872 * . Yes 873 * +--------------------+ +=============+ . +--------------------------+ 874 * | mac_tx_fanout_mode |--->v Have fanout v-*-->| goto | 875 * +--------------------+ v hint? v | mac_rx_soft_ring_process | 876 * +=============+ +--------------------------+ 877 * * . No | 878 * v ^ 879 * +===========+ | 880 * +--->v for each v +===============+ 881 * | v mblk_t v v pick softring v 882 * same * +===========+ v from hash v 883 * hash | | +===============+ 884 * | v | 885 * | +--------------+ | 886 * +---| mac_pkt_hash |--->*------------+ 887 * +--------------+ . different 888 * hash or 889 * done proc. 890 * SRS_TX_AGGR chain 891 * 892 * +------------------+ +================================+ 893 * | mac_tx_aggr_mode |--->v Use aggr capab function to v 894 * +------------------+ v find appropriate tx ring. v 895 * v Applies hash based on aggr v 896 * v policy, see mac_tx_aggr_mode() v 897 * +================================+ 898 * | 899 * v 900 * +-------------------------------+ 901 * | goto | 902 * | mac_rx_srs_soft_ring_process | 903 * +-------------------------------+ 904 * 905 * 906 * SRS_TX_BW, SRS_TX_BW_FANOUT, SRS_TX_BW_AGGR 907 * 908 * Note, all three of these tx functions start from the same place -- 909 * mac_tx_bw_mode(). 910 * 911 * +----------------+ 912 * | mac_tx_bw_mode | 913 * +----------------+ 914 * | 915 * v . No . No . Yes 916 * +==============+ . +============+ . +=============+ . +=========+ 917 * v Out of BW? v--*->v SRS empty? v--*->v reset BW v-*->v Bump BW v 918 * +==============+ +============+ v tick count? v v Usage v 919 * | | +=============+ +=========+ 920 * | +---------+ | | 921 * | | +--------------------+ | 922 * | | | +----------------------+ 923 * v | v v 924 * +===============+ | +==========+ +==========+ +------------------+ 925 * v Don't enqueue v | v set bw v v Is aggr? v--*-->| goto | 926 * v flag set? v | v enforced v +==========+ . | mac_tx_aggr_mode |-+ 927 * +===============+ | +==========+ | . +------------------+ | 928 * | Yes .* | | No . * . | 929 * | | | | | . Yes | 930 * * . No | | v | | 931 * | +---------+ | +========+ v +======+ | 932 * | | freemsg | | v append v +============+ . Yes v pick v | 933 * | +---------+ | v mblk_t v v Is fanout? v--*---->v ring v | 934 * | | | v chain v +============+ +======+ | 935 * +------+ | +========+ | | | 936 * v | | v v | 937 * +---------+ | v +-------------+ +--------------------+ | 938 * | return | | +========+ | goto | | goto | | 939 * | flow | | v wakeup v | mac_tx_send | | mac_tx_fanout_mode | | 940 * | control | | v worker v +-------------+ +--------------------+ | 941 * | cookie | | +========+ | | | 942 * +---------+ | | | +------+------+ 943 * | v | | 944 * | +---------+ | v 945 * | | return | +============+ +------------+ 946 * | | flow | v unconsumed v-------+ | done | 947 * | | control | v frames? v | | processing | 948 * | | cookie | +============+ | +------------+ 949 * | +---------+ | | 950 * | Yes * | 951 * | | | 952 * | +===========+ | 953 * | v subtract v | 954 * | v unused bw v | 955 * | +===========+ | 956 * | | | 957 * | v | 958 * | +--------------------+ | 959 * +------------->| mac_tx_srs_enqueue | | 960 * +--------------------+ | 961 * | | 962 * | | 963 * +------------+ | 964 * | return fc | | 965 * | cookie and |<------+ 966 * | mblk_t | 967 * +------------+ 968 */ 969 970 #include <sys/types.h> 971 #include <sys/callb.h> 972 #include <sys/pattr.h> 973 #include <sys/sdt.h> 974 #include <sys/strsubr.h> 975 #include <sys/strsun.h> 976 #include <sys/vlan.h> 977 #include <sys/stack.h> 978 #include <sys/archsystm.h> 979 #include <inet/ipsec_impl.h> 980 #include <inet/ip_impl.h> 981 #include <inet/sadb.h> 982 #include <inet/ipsecesp.h> 983 #include <inet/ipsecah.h> 984 #include <inet/ip6.h> 985 986 #include <sys/mac_impl.h> 987 #include <sys/mac_client_impl.h> 988 #include <sys/mac_client_priv.h> 989 #include <sys/mac_soft_ring.h> 990 #include <sys/mac_flow_impl.h> 991 992 static mac_tx_cookie_t mac_tx_single_ring_mode(mac_soft_ring_set_t *, mblk_t *, 993 uintptr_t, uint16_t, mblk_t **); 994 static mac_tx_cookie_t mac_tx_serializer_mode(mac_soft_ring_set_t *, mblk_t *, 995 uintptr_t, uint16_t, mblk_t **); 996 static mac_tx_cookie_t mac_tx_fanout_mode(mac_soft_ring_set_t *, mblk_t *, 997 uintptr_t, uint16_t, mblk_t **); 998 static mac_tx_cookie_t mac_tx_bw_mode(mac_soft_ring_set_t *, mblk_t *, 999 uintptr_t, uint16_t, mblk_t **); 1000 static mac_tx_cookie_t mac_tx_aggr_mode(mac_soft_ring_set_t *, mblk_t *, 1001 uintptr_t, uint16_t, mblk_t **); 1002 1003 typedef struct mac_tx_mode_s { 1004 mac_tx_srs_mode_t mac_tx_mode; 1005 mac_tx_func_t mac_tx_func; 1006 } mac_tx_mode_t; 1007 1008 /* 1009 * There are seven modes of operation on the Tx side. These modes get set 1010 * in mac_tx_srs_setup(). Except for the experimental TX_SERIALIZE mode, 1011 * none of the other modes are user configurable. They get selected by 1012 * the system depending upon whether the link (or flow) has multiple Tx 1013 * rings or a bandwidth configured, or if the link is an aggr, etc. 1014 * 1015 * When the Tx SRS is operating in aggr mode (st_mode) or if there are 1016 * multiple Tx rings owned by Tx SRS, then each Tx ring (pseudo or 1017 * otherwise) will have a soft ring associated with it. These soft rings 1018 * are stored in srs_tx_soft_rings[] array. 1019 * 1020 * Additionally in the case of aggr, there is the st_soft_rings[] array 1021 * in the mac_srs_tx_t structure. This array is used to store the same 1022 * set of soft rings that are present in srs_tx_soft_rings[] array but 1023 * in a different manner. The soft ring associated with the pseudo Tx 1024 * ring is saved at mr_index (of the pseudo ring) in st_soft_rings[] 1025 * array. This helps in quickly getting the soft ring associated with the 1026 * Tx ring when aggr_find_tx_ring() returns the pseudo Tx ring that is to 1027 * be used for transmit. 1028 */ 1029 mac_tx_mode_t mac_tx_mode_list[] = { 1030 {SRS_TX_DEFAULT, mac_tx_single_ring_mode}, 1031 {SRS_TX_SERIALIZE, mac_tx_serializer_mode}, 1032 {SRS_TX_FANOUT, mac_tx_fanout_mode}, 1033 {SRS_TX_BW, mac_tx_bw_mode}, 1034 {SRS_TX_BW_FANOUT, mac_tx_bw_mode}, 1035 {SRS_TX_AGGR, mac_tx_aggr_mode}, 1036 {SRS_TX_BW_AGGR, mac_tx_bw_mode} 1037 }; 1038 1039 /* 1040 * Soft Ring Set (SRS) - The Run time code that deals with 1041 * dynamic polling from the hardware, bandwidth enforcement, 1042 * fanout etc. 1043 * 1044 * We try to use H/W classification on NIC and assign traffic for 1045 * a MAC address to a particular Rx ring or ring group. There is a 1046 * 1-1 mapping between a SRS and a Rx ring. The SRS dynamically 1047 * switches the underlying Rx ring between interrupt and 1048 * polling mode and enforces any specified B/W control. 1049 * 1050 * There is always a SRS created and tied to each H/W and S/W rule. 1051 * Whenever we create a H/W rule, we always add the the same rule to 1052 * S/W classifier and tie a SRS to it. 1053 * 1054 * In case a B/W control is specified, it is broken into bytes 1055 * per ticks and as soon as the quota for a tick is exhausted, 1056 * the underlying Rx ring is forced into poll mode for remainder of 1057 * the tick. The SRS poll thread only polls for bytes that are 1058 * allowed to come in the SRS. We typically let 4x the configured 1059 * B/W worth of packets to come in the SRS (to prevent unnecessary 1060 * drops due to bursts) but only process the specified amount. 1061 * 1062 * A MAC client (e.g. a VNIC or aggr) can have 1 or more 1063 * Rx rings (and corresponding SRSs) assigned to it. The SRS 1064 * in turn can have softrings to do protocol level fanout or 1065 * softrings to do S/W based fanout or both. In case the NIC 1066 * has no Rx rings, we do S/W classification to respective SRS. 1067 * The S/W classification rule is always setup and ready. This 1068 * allows the MAC layer to reassign Rx rings whenever needed 1069 * but packets still continue to flow via the default path and 1070 * getting S/W classified to correct SRS. 1071 * 1072 * The SRS's are used on both Tx and Rx side. They use the same 1073 * data structure but the processing routines have slightly different 1074 * semantics due to the fact that Rx side needs to do dynamic 1075 * polling etc. 1076 * 1077 * Dynamic Polling Notes 1078 * ===================== 1079 * 1080 * Each Soft ring set is capable of switching its Rx ring between 1081 * interrupt and poll mode and actively 'polls' for packets in 1082 * poll mode. If the SRS is implementing a B/W limit, it makes 1083 * sure that only Max allowed packets are pulled in poll mode 1084 * and goes to poll mode as soon as B/W limit is exceeded. As 1085 * such, there are no overheads to implement B/W limits. 1086 * 1087 * In poll mode, its better to keep the pipeline going where the 1088 * SRS worker thread keeps processing packets and poll thread 1089 * keeps bringing more packets (specially if they get to run 1090 * on different CPUs). This also prevents the overheads associated 1091 * by excessive signalling (on NUMA machines, this can be 1092 * pretty devastating). The exception is latency optimized case 1093 * where worker thread does no work and interrupt and poll thread 1094 * are allowed to do their own drain. 1095 * 1096 * We use the following policy to control Dynamic Polling: 1097 * 1) We switch to poll mode anytime the processing 1098 * thread causes a backlog to build up in SRS and 1099 * its associated Soft Rings (sr_poll_pkt_cnt > 0). 1100 * 2) As long as the backlog stays under the low water 1101 * mark (sr_lowat), we poll the H/W for more packets. 1102 * 3) If the backlog (sr_poll_pkt_cnt) exceeds low 1103 * water mark, we stay in poll mode but don't poll 1104 * the H/W for more packets. 1105 * 4) Anytime in polling mode, if we poll the H/W for 1106 * packets and find nothing plus we have an existing 1107 * backlog (sr_poll_pkt_cnt > 0), we stay in polling 1108 * mode but don't poll the H/W for packets anymore 1109 * (let the polling thread go to sleep). 1110 * 5) Once the backlog is relived (packets are processed) 1111 * we reenable polling (by signalling the poll thread) 1112 * only when the backlog dips below sr_poll_thres. 1113 * 6) sr_hiwat is used exclusively when we are not 1114 * polling capable and is used to decide when to 1115 * drop packets so the SRS queue length doesn't grow 1116 * infinitely. 1117 * 1118 * NOTE: Also see the block level comment on top of mac_soft_ring.c 1119 */ 1120 1121 /* 1122 * mac_latency_optimize 1123 * 1124 * Controls whether the poll thread can process the packets inline 1125 * or let the SRS worker thread do the processing. This applies if 1126 * the SRS was not being processed. For latency sensitive traffic, 1127 * this needs to be true to allow inline processing. For throughput 1128 * under load, this should be false. 1129 * 1130 * This (and other similar) tunable should be rolled into a link 1131 * or flow specific workload hint that can be set using dladm 1132 * linkprop (instead of multiple such tunables). 1133 */ 1134 boolean_t mac_latency_optimize = B_TRUE; 1135 1136 /* 1137 * MAC_RX_SRS_ENQUEUE_CHAIN and MAC_TX_SRS_ENQUEUE_CHAIN 1138 * 1139 * queue a mp or chain in soft ring set and increment the 1140 * local count (srs_count) for the SRS and the shared counter 1141 * (srs_poll_pkt_cnt - shared between SRS and its soft rings 1142 * to track the total unprocessed packets for polling to work 1143 * correctly). 1144 * 1145 * The size (total bytes queued) counters are incremented only 1146 * if we are doing B/W control. 1147 */ 1148 #define MAC_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz) { \ 1149 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \ 1150 if ((mac_srs)->srs_last != NULL) \ 1151 (mac_srs)->srs_last->b_next = (head); \ 1152 else \ 1153 (mac_srs)->srs_first = (head); \ 1154 (mac_srs)->srs_last = (tail); \ 1155 (mac_srs)->srs_count += count; \ 1156 } 1157 1158 #define MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz) { \ 1159 mac_srs_rx_t *srs_rx = &(mac_srs)->srs_rx; \ 1160 \ 1161 MAC_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz); \ 1162 srs_rx->sr_poll_pkt_cnt += count; \ 1163 ASSERT(srs_rx->sr_poll_pkt_cnt > 0); \ 1164 if ((mac_srs)->srs_type & SRST_BW_CONTROL) { \ 1165 (mac_srs)->srs_size += (sz); \ 1166 mutex_enter(&(mac_srs)->srs_bw->mac_bw_lock); \ 1167 (mac_srs)->srs_bw->mac_bw_sz += (sz); \ 1168 mutex_exit(&(mac_srs)->srs_bw->mac_bw_lock); \ 1169 } \ 1170 } 1171 1172 #define MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz) { \ 1173 mac_srs->srs_state |= SRS_ENQUEUED; \ 1174 MAC_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz); \ 1175 if ((mac_srs)->srs_type & SRST_BW_CONTROL) { \ 1176 (mac_srs)->srs_size += (sz); \ 1177 (mac_srs)->srs_bw->mac_bw_sz += (sz); \ 1178 } \ 1179 } 1180 1181 /* 1182 * Turn polling on routines 1183 */ 1184 #define MAC_SRS_POLLING_ON(mac_srs) { \ 1185 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \ 1186 if (((mac_srs)->srs_state & \ 1187 (SRS_POLLING_CAPAB|SRS_POLLING)) == SRS_POLLING_CAPAB) { \ 1188 (mac_srs)->srs_state |= SRS_POLLING; \ 1189 (void) mac_hwring_disable_intr((mac_ring_handle_t) \ 1190 (mac_srs)->srs_ring); \ 1191 (mac_srs)->srs_rx.sr_poll_on++; \ 1192 } \ 1193 } 1194 1195 #define MAC_SRS_WORKER_POLLING_ON(mac_srs) { \ 1196 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \ 1197 if (((mac_srs)->srs_state & \ 1198 (SRS_POLLING_CAPAB|SRS_WORKER|SRS_POLLING)) == \ 1199 (SRS_POLLING_CAPAB|SRS_WORKER)) { \ 1200 (mac_srs)->srs_state |= SRS_POLLING; \ 1201 (void) mac_hwring_disable_intr((mac_ring_handle_t) \ 1202 (mac_srs)->srs_ring); \ 1203 (mac_srs)->srs_rx.sr_worker_poll_on++; \ 1204 } \ 1205 } 1206 1207 /* 1208 * MAC_SRS_POLL_RING 1209 * 1210 * Signal the SRS poll thread to poll the underlying H/W ring 1211 * provided it wasn't already polling (SRS_GET_PKTS was set). 1212 * 1213 * Poll thread gets to run only from mac_rx_srs_drain() and only 1214 * if the drain was being done by the worker thread. 1215 */ 1216 #define MAC_SRS_POLL_RING(mac_srs) { \ 1217 mac_srs_rx_t *srs_rx = &(mac_srs)->srs_rx; \ 1218 \ 1219 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \ 1220 srs_rx->sr_poll_thr_sig++; \ 1221 if (((mac_srs)->srs_state & \ 1222 (SRS_POLLING_CAPAB|SRS_WORKER|SRS_GET_PKTS)) == \ 1223 (SRS_WORKER|SRS_POLLING_CAPAB)) { \ 1224 (mac_srs)->srs_state |= SRS_GET_PKTS; \ 1225 cv_signal(&(mac_srs)->srs_cv); \ 1226 } else { \ 1227 srs_rx->sr_poll_thr_busy++; \ 1228 } \ 1229 } 1230 1231 /* 1232 * MAC_SRS_CHECK_BW_CONTROL 1233 * 1234 * Check to see if next tick has started so we can reset the 1235 * SRS_BW_ENFORCED flag and allow more packets to come in the 1236 * system. 1237 */ 1238 #define MAC_SRS_CHECK_BW_CONTROL(mac_srs) { \ 1239 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \ 1240 ASSERT(((mac_srs)->srs_type & SRST_TX) || \ 1241 MUTEX_HELD(&(mac_srs)->srs_bw->mac_bw_lock)); \ 1242 clock_t now = ddi_get_lbolt(); \ 1243 if ((mac_srs)->srs_bw->mac_bw_curr_time != now) { \ 1244 (mac_srs)->srs_bw->mac_bw_curr_time = now; \ 1245 (mac_srs)->srs_bw->mac_bw_used = 0; \ 1246 if ((mac_srs)->srs_bw->mac_bw_state & SRS_BW_ENFORCED) \ 1247 (mac_srs)->srs_bw->mac_bw_state &= ~SRS_BW_ENFORCED; \ 1248 } \ 1249 } 1250 1251 /* 1252 * MAC_SRS_WORKER_WAKEUP 1253 * 1254 * Wake up the SRS worker thread to process the queue as long as 1255 * no one else is processing the queue. If we are optimizing for 1256 * latency, we wake up the worker thread immediately or else we 1257 * wait mac_srs_worker_wakeup_ticks before worker thread gets 1258 * woken up. 1259 */ 1260 int mac_srs_worker_wakeup_ticks = 0; 1261 #define MAC_SRS_WORKER_WAKEUP(mac_srs) { \ 1262 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \ 1263 if (!((mac_srs)->srs_state & SRS_PROC) && \ 1264 (mac_srs)->srs_tid == NULL) { \ 1265 if (((mac_srs)->srs_state & SRS_LATENCY_OPT) || \ 1266 (mac_srs_worker_wakeup_ticks == 0)) \ 1267 cv_signal(&(mac_srs)->srs_async); \ 1268 else \ 1269 (mac_srs)->srs_tid = \ 1270 timeout(mac_srs_fire, (mac_srs), \ 1271 mac_srs_worker_wakeup_ticks); \ 1272 } \ 1273 } 1274 1275 #define TX_BANDWIDTH_MODE(mac_srs) \ 1276 ((mac_srs)->srs_tx.st_mode == SRS_TX_BW || \ 1277 (mac_srs)->srs_tx.st_mode == SRS_TX_BW_FANOUT || \ 1278 (mac_srs)->srs_tx.st_mode == SRS_TX_BW_AGGR) 1279 1280 #define TX_SRS_TO_SOFT_RING(mac_srs, head, hint) { \ 1281 if (tx_mode == SRS_TX_BW_FANOUT) \ 1282 (void) mac_tx_fanout_mode(mac_srs, head, hint, 0, NULL);\ 1283 else \ 1284 (void) mac_tx_aggr_mode(mac_srs, head, hint, 0, NULL); \ 1285 } 1286 1287 /* 1288 * MAC_TX_SRS_BLOCK 1289 * 1290 * Always called from mac_tx_srs_drain() function. SRS_TX_BLOCKED 1291 * will be set only if srs_tx_woken_up is FALSE. If 1292 * srs_tx_woken_up is TRUE, it indicates that the wakeup arrived 1293 * before we grabbed srs_lock to set SRS_TX_BLOCKED. We need to 1294 * attempt to transmit again and not setting SRS_TX_BLOCKED does 1295 * that. 1296 */ 1297 #define MAC_TX_SRS_BLOCK(srs, mp) { \ 1298 ASSERT(MUTEX_HELD(&(srs)->srs_lock)); \ 1299 if ((srs)->srs_tx.st_woken_up) { \ 1300 (srs)->srs_tx.st_woken_up = B_FALSE; \ 1301 } else { \ 1302 ASSERT(!((srs)->srs_state & SRS_TX_BLOCKED)); \ 1303 (srs)->srs_state |= SRS_TX_BLOCKED; \ 1304 (srs)->srs_tx.st_stat.mts_blockcnt++; \ 1305 } \ 1306 } 1307 1308 /* 1309 * MAC_TX_SRS_TEST_HIWAT 1310 * 1311 * Called before queueing a packet onto Tx SRS to test and set 1312 * SRS_TX_HIWAT if srs_count exceeds srs_tx_hiwat. 1313 */ 1314 #define MAC_TX_SRS_TEST_HIWAT(srs, mp, tail, cnt, sz, cookie) { \ 1315 boolean_t enqueue = 1; \ 1316 \ 1317 if ((srs)->srs_count > (srs)->srs_tx.st_hiwat) { \ 1318 /* \ 1319 * flow-controlled. Store srs in cookie so that it \ 1320 * can be returned as mac_tx_cookie_t to client \ 1321 */ \ 1322 (srs)->srs_state |= SRS_TX_HIWAT; \ 1323 cookie = (mac_tx_cookie_t)srs; \ 1324 (srs)->srs_tx.st_hiwat_cnt++; \ 1325 if ((srs)->srs_count > (srs)->srs_tx.st_max_q_cnt) { \ 1326 /* increment freed stats */ \ 1327 (srs)->srs_tx.st_stat.mts_sdrops += cnt; \ 1328 /* \ 1329 * b_prev may be set to the fanout hint \ 1330 * hence can't use freemsg directly \ 1331 */ \ 1332 mac_drop_chain(mp_chain, "SRS Tx max queue"); \ 1333 DTRACE_PROBE1(tx_queued_hiwat, \ 1334 mac_soft_ring_set_t *, srs); \ 1335 enqueue = 0; \ 1336 } \ 1337 } \ 1338 if (enqueue) \ 1339 MAC_TX_SRS_ENQUEUE_CHAIN(srs, mp, tail, cnt, sz); \ 1340 } 1341 1342 /* Some utility macros */ 1343 #define MAC_SRS_BW_LOCK(srs) \ 1344 if (!(srs->srs_type & SRST_TX)) \ 1345 mutex_enter(&srs->srs_bw->mac_bw_lock); 1346 1347 #define MAC_SRS_BW_UNLOCK(srs) \ 1348 if (!(srs->srs_type & SRST_TX)) \ 1349 mutex_exit(&srs->srs_bw->mac_bw_lock); 1350 1351 #define MAC_TX_SRS_DROP_MESSAGE(srs, chain, cookie, s) { \ 1352 mac_drop_chain((chain), (s)); \ 1353 /* increment freed stats */ \ 1354 (srs)->srs_tx.st_stat.mts_sdrops++; \ 1355 (cookie) = (mac_tx_cookie_t)(srs); \ 1356 } 1357 1358 #define MAC_TX_SET_NO_ENQUEUE(srs, mp_chain, ret_mp, cookie) { \ 1359 mac_srs->srs_state |= SRS_TX_WAKEUP_CLIENT; \ 1360 cookie = (mac_tx_cookie_t)srs; \ 1361 *ret_mp = mp_chain; \ 1362 } 1363 1364 /* 1365 * Threshold used in receive-side processing to determine if handling 1366 * can occur in situ (in the interrupt thread) or if it should be left to a 1367 * worker thread. Note that the constant used to make this determination is 1368 * not entirely made-up, and is a result of some emprical validation. That 1369 * said, the constant is left as a global variable to allow it to be 1370 * dynamically tuned in the field if and as needed. 1371 */ 1372 uintptr_t mac_rx_srs_stack_needed = 14336; 1373 uint_t mac_rx_srs_stack_toodeep; 1374 1375 #ifndef STACK_GROWTH_DOWN 1376 #error Downward stack growth assumed. 1377 #endif 1378 1379 /* 1380 * Drop the rx packet and advance to the next one in the chain. 1381 */ 1382 static void 1383 mac_rx_drop_pkt(mac_soft_ring_set_t *srs, mblk_t *mp) 1384 { 1385 mac_srs_rx_t *srs_rx = &srs->srs_rx; 1386 1387 ASSERT(mp->b_next == NULL); 1388 mutex_enter(&srs->srs_lock); 1389 MAC_UPDATE_SRS_COUNT_LOCKED(srs, 1); 1390 MAC_UPDATE_SRS_SIZE_LOCKED(srs, msgdsize(mp)); 1391 mutex_exit(&srs->srs_lock); 1392 1393 srs_rx->sr_stat.mrs_sdrops++; 1394 freemsg(mp); 1395 } 1396 1397 /* DATAPATH RUNTIME ROUTINES */ 1398 1399 /* 1400 * mac_srs_fire 1401 * 1402 * Timer callback routine for waking up the SRS worker thread. 1403 */ 1404 static void 1405 mac_srs_fire(void *arg) 1406 { 1407 mac_soft_ring_set_t *mac_srs = (mac_soft_ring_set_t *)arg; 1408 1409 mutex_enter(&mac_srs->srs_lock); 1410 if (mac_srs->srs_tid == NULL) { 1411 mutex_exit(&mac_srs->srs_lock); 1412 return; 1413 } 1414 1415 mac_srs->srs_tid = NULL; 1416 if (!(mac_srs->srs_state & SRS_PROC)) 1417 cv_signal(&mac_srs->srs_async); 1418 1419 mutex_exit(&mac_srs->srs_lock); 1420 } 1421 1422 /* 1423 * 'hint' is fanout_hint (type of uint64_t) which is given by the TCP/IP stack, 1424 * and it is used on the TX path. 1425 */ 1426 #define HASH_HINT(hint) \ 1427 ((hint) ^ ((hint) >> 24) ^ ((hint) >> 16) ^ ((hint) >> 8)) 1428 1429 1430 /* 1431 * hash based on the src address, dst address and the port information. 1432 */ 1433 #define HASH_ADDR(src, dst, ports) \ 1434 (ntohl((src) + (dst)) ^ ((ports) >> 24) ^ ((ports) >> 16) ^ \ 1435 ((ports) >> 8) ^ (ports)) 1436 1437 #define COMPUTE_INDEX(key, sz) (key % sz) 1438 1439 #define FANOUT_ENQUEUE_MP(head, tail, cnt, bw_ctl, sz, sz0, mp) { \ 1440 if ((tail) != NULL) { \ 1441 ASSERT((tail)->b_next == NULL); \ 1442 (tail)->b_next = (mp); \ 1443 } else { \ 1444 ASSERT((head) == NULL); \ 1445 (head) = (mp); \ 1446 } \ 1447 (tail) = (mp); \ 1448 (cnt)++; \ 1449 if ((bw_ctl)) \ 1450 (sz) += (sz0); \ 1451 } 1452 1453 #define MAC_FANOUT_DEFAULT 0 1454 #define MAC_FANOUT_RND_ROBIN 1 1455 int mac_fanout_type = MAC_FANOUT_DEFAULT; 1456 1457 #define MAX_SR_TYPES 3 1458 /* fanout types for port based hashing */ 1459 enum pkt_type { 1460 V4_TCP = 0, 1461 V4_UDP, 1462 OTH, 1463 UNDEF 1464 }; 1465 1466 /* 1467 * Pair of local and remote ports in the transport header 1468 */ 1469 #define PORTS_SIZE 4 1470 1471 /* 1472 * This routine delivers packets destined for an SRS into one of the 1473 * protocol soft rings. 1474 * 1475 * Given a chain of packets we need to split it up into multiple sub 1476 * chains: TCP, UDP or OTH soft ring. Instead of entering the soft 1477 * ring one packet at a time, we want to enter it in the form of a 1478 * chain otherwise we get this start/stop behaviour where the worker 1479 * thread goes to sleep and then next packet comes in forcing it to 1480 * wake up. 1481 */ 1482 static void 1483 mac_rx_srs_proto_fanout(mac_soft_ring_set_t *mac_srs, mblk_t *head) 1484 { 1485 struct ether_header *ehp; 1486 struct ether_vlan_header *evhp; 1487 uint32_t sap; 1488 ipha_t *ipha; 1489 uint8_t *dstaddr; 1490 size_t hdrsize; 1491 mblk_t *mp; 1492 mblk_t *headmp[MAX_SR_TYPES]; 1493 mblk_t *tailmp[MAX_SR_TYPES]; 1494 int cnt[MAX_SR_TYPES]; 1495 size_t sz[MAX_SR_TYPES]; 1496 size_t sz1; 1497 boolean_t bw_ctl; 1498 boolean_t hw_classified; 1499 boolean_t dls_bypass; 1500 boolean_t is_ether; 1501 boolean_t is_unicast; 1502 enum pkt_type type; 1503 mac_client_impl_t *mcip = mac_srs->srs_mcip; 1504 1505 is_ether = (mcip->mci_mip->mi_info.mi_nativemedia == DL_ETHER); 1506 bw_ctl = ((mac_srs->srs_type & SRST_BW_CONTROL) != 0); 1507 1508 /* 1509 * If we don't have a Rx ring, S/W classification would have done 1510 * its job and its a packet meant for us. If we were polling on 1511 * the default ring (i.e. there was a ring assigned to this SRS), 1512 * then we need to make sure that the mac address really belongs 1513 * to us. 1514 */ 1515 hw_classified = mac_srs->srs_ring != NULL && 1516 mac_srs->srs_ring->mr_classify_type == MAC_HW_CLASSIFIER; 1517 1518 /* 1519 * Some clients, such as non-ethernet, need DLS processing in 1520 * the Rx path. Such clients clear the SRST_DLS_BYPASS flag. 1521 * DLS bypass may also be disabled via the 1522 * MCIS_RX_BYPASS_DISABLE flag. 1523 */ 1524 dls_bypass = ((mac_srs->srs_type & SRST_DLS_BYPASS) != 0) && 1525 ((mcip->mci_state_flags & MCIS_RX_BYPASS_DISABLE) == 0); 1526 1527 bzero(headmp, MAX_SR_TYPES * sizeof (mblk_t *)); 1528 bzero(tailmp, MAX_SR_TYPES * sizeof (mblk_t *)); 1529 bzero(cnt, MAX_SR_TYPES * sizeof (int)); 1530 bzero(sz, MAX_SR_TYPES * sizeof (size_t)); 1531 1532 /* 1533 * We have a chain from SRS that we need to split across the 1534 * soft rings. The squeues for the TCP and IPv4 SAPs use their 1535 * own soft rings to allow polling from the squeue. The rest of 1536 * the packets are delivered on the OTH soft ring which cannot 1537 * be polled. 1538 */ 1539 while (head != NULL) { 1540 mp = head; 1541 head = head->b_next; 1542 mp->b_next = NULL; 1543 1544 type = OTH; 1545 sz1 = (mp->b_cont == NULL) ? MBLKL(mp) : msgdsize(mp); 1546 1547 if (is_ether) { 1548 /* 1549 * At this point we can be sure the packet at least 1550 * has an ether header. 1551 */ 1552 if (sz1 < sizeof (struct ether_header)) { 1553 mac_rx_drop_pkt(mac_srs, mp); 1554 continue; 1555 } 1556 ehp = (struct ether_header *)mp->b_rptr; 1557 1558 /* 1559 * Determine if this is a VLAN or non-VLAN packet. 1560 */ 1561 if ((sap = ntohs(ehp->ether_type)) == VLAN_TPID) { 1562 evhp = (struct ether_vlan_header *)mp->b_rptr; 1563 sap = ntohs(evhp->ether_type); 1564 hdrsize = sizeof (struct ether_vlan_header); 1565 1566 /* 1567 * Check if the VID of the packet, if 1568 * any, belongs to this client. 1569 * Technically, if this packet came up 1570 * via a HW classified ring then we 1571 * don't need to perform this check. 1572 * Perhaps a future optimization. 1573 */ 1574 if (!mac_client_check_flow_vid(mcip, 1575 VLAN_ID(ntohs(evhp->ether_tci)))) { 1576 mac_rx_drop_pkt(mac_srs, mp); 1577 continue; 1578 } 1579 } else { 1580 hdrsize = sizeof (struct ether_header); 1581 } 1582 is_unicast = 1583 ((((uint8_t *)&ehp->ether_dhost)[0] & 0x01) == 0); 1584 dstaddr = (uint8_t *)&ehp->ether_dhost; 1585 } else { 1586 mac_header_info_t mhi; 1587 1588 if (mac_header_info((mac_handle_t)mcip->mci_mip, 1589 mp, &mhi) != 0) { 1590 mac_rx_drop_pkt(mac_srs, mp); 1591 continue; 1592 } 1593 hdrsize = mhi.mhi_hdrsize; 1594 sap = mhi.mhi_bindsap; 1595 is_unicast = (mhi.mhi_dsttype == MAC_ADDRTYPE_UNICAST); 1596 dstaddr = (uint8_t *)mhi.mhi_daddr; 1597 } 1598 1599 if (!dls_bypass) { 1600 FANOUT_ENQUEUE_MP(headmp[type], tailmp[type], 1601 cnt[type], bw_ctl, sz[type], sz1, mp); 1602 continue; 1603 } 1604 1605 if (sap == ETHERTYPE_IP) { 1606 /* 1607 * If we are H/W classified, but we have promisc 1608 * on, then we need to check for the unicast address. 1609 */ 1610 if (hw_classified && mcip->mci_promisc_list != NULL) { 1611 mac_address_t *map; 1612 1613 rw_enter(&mcip->mci_rw_lock, RW_READER); 1614 map = mcip->mci_unicast; 1615 if (bcmp(dstaddr, map->ma_addr, 1616 map->ma_len) == 0) 1617 type = UNDEF; 1618 rw_exit(&mcip->mci_rw_lock); 1619 } else if (is_unicast) { 1620 type = UNDEF; 1621 } 1622 } 1623 1624 /* 1625 * This needs to become a contract with the driver for 1626 * the fast path. 1627 * 1628 * In the normal case the packet will have at least the L2 1629 * header and the IP + Transport header in the same mblk. 1630 * This is usually the case when the NIC driver sends up 1631 * the packet. This is also true when the stack generates 1632 * a packet that is looped back and when the stack uses the 1633 * fastpath mechanism. The normal case is optimized for 1634 * performance and may bypass DLS. All other cases go through 1635 * the 'OTH' type path without DLS bypass. 1636 */ 1637 ipha = (ipha_t *)(mp->b_rptr + hdrsize); 1638 if ((type != OTH) && MBLK_RX_FANOUT_SLOWPATH(mp, ipha)) 1639 type = OTH; 1640 1641 if (type == OTH) { 1642 FANOUT_ENQUEUE_MP(headmp[type], tailmp[type], 1643 cnt[type], bw_ctl, sz[type], sz1, mp); 1644 continue; 1645 } 1646 1647 ASSERT(type == UNDEF); 1648 1649 /* 1650 * Determine the type from the IP protocol value. If 1651 * classified as TCP or UDP, then update the read 1652 * pointer to the beginning of the IP header. 1653 * Otherwise leave the message as is for further 1654 * processing by DLS. 1655 */ 1656 switch (ipha->ipha_protocol) { 1657 case IPPROTO_TCP: 1658 type = V4_TCP; 1659 mp->b_rptr += hdrsize; 1660 break; 1661 case IPPROTO_UDP: 1662 type = V4_UDP; 1663 mp->b_rptr += hdrsize; 1664 break; 1665 default: 1666 type = OTH; 1667 break; 1668 } 1669 1670 FANOUT_ENQUEUE_MP(headmp[type], tailmp[type], cnt[type], 1671 bw_ctl, sz[type], sz1, mp); 1672 } 1673 1674 for (type = V4_TCP; type < UNDEF; type++) { 1675 if (headmp[type] != NULL) { 1676 mac_soft_ring_t *softring; 1677 1678 ASSERT(tailmp[type]->b_next == NULL); 1679 switch (type) { 1680 case V4_TCP: 1681 softring = mac_srs->srs_tcp_soft_rings[0]; 1682 break; 1683 case V4_UDP: 1684 softring = mac_srs->srs_udp_soft_rings[0]; 1685 break; 1686 case OTH: 1687 softring = mac_srs->srs_oth_soft_rings[0]; 1688 } 1689 mac_rx_soft_ring_process(mcip, softring, 1690 headmp[type], tailmp[type], cnt[type], sz[type]); 1691 } 1692 } 1693 } 1694 1695 int fanout_unaligned = 0; 1696 1697 /* 1698 * The fanout routine for any clients with DLS bypass disabled or for 1699 * traffic classified as "other". Returns -1 on an error (drop the 1700 * packet due to a malformed packet), 0 on success, with values 1701 * written in *indx and *type. 1702 */ 1703 static int 1704 mac_rx_srs_long_fanout(mac_soft_ring_set_t *mac_srs, mblk_t *mp, 1705 uint32_t sap, size_t hdrsize, enum pkt_type *type, uint_t *indx) 1706 { 1707 ip6_t *ip6h; 1708 ipha_t *ipha; 1709 uint8_t *whereptr; 1710 uint_t hash; 1711 uint16_t remlen; 1712 uint8_t nexthdr; 1713 uint16_t hdr_len; 1714 uint32_t src_val, dst_val; 1715 boolean_t modifiable = B_TRUE; 1716 boolean_t v6; 1717 1718 ASSERT(MBLKL(mp) >= hdrsize); 1719 1720 if (sap == ETHERTYPE_IPV6) { 1721 v6 = B_TRUE; 1722 hdr_len = IPV6_HDR_LEN; 1723 } else if (sap == ETHERTYPE_IP) { 1724 v6 = B_FALSE; 1725 hdr_len = IP_SIMPLE_HDR_LENGTH; 1726 } else { 1727 *indx = 0; 1728 *type = OTH; 1729 return (0); 1730 } 1731 1732 ip6h = (ip6_t *)(mp->b_rptr + hdrsize); 1733 ipha = (ipha_t *)ip6h; 1734 1735 if ((uint8_t *)ip6h == mp->b_wptr) { 1736 /* 1737 * The first mblk_t only includes the mac header. 1738 * Note that it is safe to change the mp pointer here, 1739 * as the subsequent operation does not assume mp 1740 * points to the start of the mac header. 1741 */ 1742 mp = mp->b_cont; 1743 1744 /* 1745 * Make sure the IP header points to an entire one. 1746 */ 1747 if (mp == NULL) 1748 return (-1); 1749 1750 if (MBLKL(mp) < hdr_len) { 1751 modifiable = (DB_REF(mp) == 1); 1752 1753 if (modifiable && !pullupmsg(mp, hdr_len)) 1754 return (-1); 1755 } 1756 1757 ip6h = (ip6_t *)mp->b_rptr; 1758 ipha = (ipha_t *)ip6h; 1759 } 1760 1761 if (!modifiable || !(OK_32PTR((char *)ip6h)) || 1762 ((uint8_t *)ip6h + hdr_len > mp->b_wptr)) { 1763 /* 1764 * If either the IP header is not aligned, or it does not hold 1765 * the complete simple structure (a pullupmsg() is not an 1766 * option since it would result in an unaligned IP header), 1767 * fanout to the default ring. 1768 * 1769 * Note that this may cause packet reordering. 1770 */ 1771 *indx = 0; 1772 *type = OTH; 1773 fanout_unaligned++; 1774 return (0); 1775 } 1776 1777 /* 1778 * Extract next-header, full header length, and source-hash value 1779 * using v4/v6 specific fields. 1780 */ 1781 if (v6) { 1782 remlen = ntohs(ip6h->ip6_plen); 1783 nexthdr = ip6h->ip6_nxt; 1784 src_val = V4_PART_OF_V6(ip6h->ip6_src); 1785 dst_val = V4_PART_OF_V6(ip6h->ip6_dst); 1786 /* 1787 * Do src based fanout if below tunable is set to B_TRUE or 1788 * when mac_ip_hdr_length_v6() fails because of malformed 1789 * packets or because mblks need to be concatenated using 1790 * pullupmsg(). 1791 * 1792 * Perform a version check to prevent parsing weirdness... 1793 */ 1794 if (IPH_HDR_VERSION(ip6h) != IPV6_VERSION || 1795 !mac_ip_hdr_length_v6(ip6h, mp->b_wptr, &hdr_len, &nexthdr, 1796 NULL)) { 1797 goto src_dst_based_fanout; 1798 } 1799 } else { 1800 hdr_len = IPH_HDR_LENGTH(ipha); 1801 remlen = ntohs(ipha->ipha_length) - hdr_len; 1802 nexthdr = ipha->ipha_protocol; 1803 src_val = (uint32_t)ipha->ipha_src; 1804 dst_val = (uint32_t)ipha->ipha_dst; 1805 /* 1806 * Catch IPv4 fragment case here. IPv6 has nexthdr == FRAG 1807 * for its equivalent case. 1808 */ 1809 if ((ntohs(ipha->ipha_fragment_offset_and_flags) & 1810 (IPH_MF | IPH_OFFSET)) != 0) { 1811 goto src_dst_based_fanout; 1812 } 1813 } 1814 if (remlen < MIN_EHDR_LEN) 1815 return (-1); 1816 whereptr = (uint8_t *)ip6h + hdr_len; 1817 1818 /* If the transport is one of below, we do port/SPI based fanout */ 1819 switch (nexthdr) { 1820 case IPPROTO_TCP: 1821 case IPPROTO_UDP: 1822 case IPPROTO_SCTP: 1823 case IPPROTO_ESP: 1824 /* 1825 * If the ports or SPI in the transport header is not part of 1826 * the mblk, do src_based_fanout, instead of calling 1827 * pullupmsg(). 1828 */ 1829 if (mp->b_cont == NULL || whereptr + PORTS_SIZE <= mp->b_wptr) 1830 break; /* out of switch... */ 1831 /* FALLTHRU */ 1832 default: 1833 goto src_dst_based_fanout; 1834 } 1835 1836 switch (nexthdr) { 1837 case IPPROTO_TCP: 1838 hash = HASH_ADDR(src_val, dst_val, *(uint32_t *)whereptr); 1839 *indx = COMPUTE_INDEX(hash, mac_srs->srs_tcp_ring_count); 1840 *type = OTH; 1841 break; 1842 case IPPROTO_UDP: 1843 case IPPROTO_SCTP: 1844 case IPPROTO_ESP: 1845 if (mac_fanout_type == MAC_FANOUT_DEFAULT) { 1846 hash = HASH_ADDR(src_val, dst_val, 1847 *(uint32_t *)whereptr); 1848 *indx = COMPUTE_INDEX(hash, 1849 mac_srs->srs_udp_ring_count); 1850 } else { 1851 *indx = mac_srs->srs_ind % mac_srs->srs_udp_ring_count; 1852 mac_srs->srs_ind++; 1853 } 1854 *type = OTH; 1855 break; 1856 } 1857 return (0); 1858 1859 src_dst_based_fanout: 1860 hash = HASH_ADDR(src_val, dst_val, (uint32_t)0); 1861 *indx = COMPUTE_INDEX(hash, mac_srs->srs_oth_ring_count); 1862 *type = OTH; 1863 return (0); 1864 } 1865 1866 /* 1867 * This routine delivers packets destined for an SRS into a soft ring member 1868 * of the set. 1869 * 1870 * Given a chain of packets we need to split it up into multiple sub 1871 * chains: TCP, UDP or OTH soft ring. Instead of entering the soft 1872 * ring one packet at a time, we want to enter it in the form of a 1873 * chain otherwise we get this start/stop behaviour where the worker 1874 * thread goes to sleep and then next packet comes in forcing it to 1875 * wake up. 1876 * 1877 * Note: 1878 * Since we know what is the maximum fanout possible, we create a 2D array 1879 * of 'softring types * MAX_SR_FANOUT' for the head, tail, cnt and sz 1880 * variables so that we can enter the softrings with chain. We need the 1881 * MAX_SR_FANOUT so we can allocate the arrays on the stack (a kmem_alloc 1882 * for each packet would be expensive). If we ever want to have the 1883 * ability to have unlimited fanout, we should probably declare a head, 1884 * tail, cnt, sz with each soft ring (a data struct which contains a softring 1885 * along with these members) and create an array of this uber struct so we 1886 * don't have to do kmem_alloc. 1887 */ 1888 int fanout_oth1 = 0; 1889 int fanout_oth2 = 0; 1890 int fanout_oth3 = 0; 1891 int fanout_oth4 = 0; 1892 int fanout_oth5 = 0; 1893 1894 static void 1895 mac_rx_srs_fanout(mac_soft_ring_set_t *mac_srs, mblk_t *head) 1896 { 1897 struct ether_header *ehp; 1898 struct ether_vlan_header *evhp; 1899 uint32_t sap; 1900 ipha_t *ipha; 1901 uint8_t *dstaddr; 1902 uint_t indx; 1903 size_t ports_offset; 1904 size_t ipha_len; 1905 size_t hdrsize; 1906 uint_t hash; 1907 mblk_t *mp; 1908 mblk_t *headmp[MAX_SR_TYPES][MAX_SR_FANOUT]; 1909 mblk_t *tailmp[MAX_SR_TYPES][MAX_SR_FANOUT]; 1910 int cnt[MAX_SR_TYPES][MAX_SR_FANOUT]; 1911 size_t sz[MAX_SR_TYPES][MAX_SR_FANOUT]; 1912 size_t sz1; 1913 boolean_t bw_ctl; 1914 boolean_t hw_classified; 1915 boolean_t dls_bypass; 1916 boolean_t is_ether; 1917 boolean_t is_unicast; 1918 int fanout_cnt; 1919 enum pkt_type type; 1920 mac_client_impl_t *mcip = mac_srs->srs_mcip; 1921 1922 is_ether = (mcip->mci_mip->mi_info.mi_nativemedia == DL_ETHER); 1923 bw_ctl = ((mac_srs->srs_type & SRST_BW_CONTROL) != 0); 1924 1925 /* 1926 * If we don't have a Rx ring, S/W classification would have done 1927 * its job and its a packet meant for us. If we were polling on 1928 * the default ring (i.e. there was a ring assigned to this SRS), 1929 * then we need to make sure that the mac address really belongs 1930 * to us. 1931 */ 1932 hw_classified = mac_srs->srs_ring != NULL && 1933 mac_srs->srs_ring->mr_classify_type == MAC_HW_CLASSIFIER; 1934 1935 /* 1936 * Some clients, such as non Ethernet, need DLS processing in 1937 * the Rx path. Such clients clear the SRST_DLS_BYPASS flag. 1938 * DLS bypass may also be disabled via the 1939 * MCIS_RX_BYPASS_DISABLE flag, but this is only consumed by 1940 * sun4v vsw currently. 1941 */ 1942 dls_bypass = ((mac_srs->srs_type & SRST_DLS_BYPASS) != 0) && 1943 ((mcip->mci_state_flags & MCIS_RX_BYPASS_DISABLE) == 0); 1944 1945 /* 1946 * Since the softrings are never destroyed and we always 1947 * create equal number of softrings for TCP, UDP and rest, 1948 * its OK to check one of them for count and use it without 1949 * any lock. In future, if soft rings get destroyed because 1950 * of reduction in fanout, we will need to ensure that happens 1951 * behind the SRS_PROC. 1952 */ 1953 fanout_cnt = mac_srs->srs_tcp_ring_count; 1954 1955 bzero(headmp, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (mblk_t *)); 1956 bzero(tailmp, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (mblk_t *)); 1957 bzero(cnt, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (int)); 1958 bzero(sz, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (size_t)); 1959 1960 /* 1961 * We got a chain from SRS that we need to send to the soft rings. 1962 * Since squeues for TCP & IPv4 SAP poll their soft rings (for 1963 * performance reasons), we need to separate out v4_tcp, v4_udp 1964 * and the rest goes in other. 1965 */ 1966 while (head != NULL) { 1967 mp = head; 1968 head = head->b_next; 1969 mp->b_next = NULL; 1970 1971 type = OTH; 1972 sz1 = (mp->b_cont == NULL) ? MBLKL(mp) : msgdsize(mp); 1973 1974 if (is_ether) { 1975 /* 1976 * At this point we can be sure the packet at least 1977 * has an ether header. 1978 */ 1979 if (sz1 < sizeof (struct ether_header)) { 1980 mac_rx_drop_pkt(mac_srs, mp); 1981 continue; 1982 } 1983 ehp = (struct ether_header *)mp->b_rptr; 1984 1985 /* 1986 * Determine if this is a VLAN or non-VLAN packet. 1987 */ 1988 if ((sap = ntohs(ehp->ether_type)) == VLAN_TPID) { 1989 evhp = (struct ether_vlan_header *)mp->b_rptr; 1990 sap = ntohs(evhp->ether_type); 1991 hdrsize = sizeof (struct ether_vlan_header); 1992 1993 /* 1994 * Check if the VID of the packet, if 1995 * any, belongs to this client. 1996 * Technically, if this packet came up 1997 * via a HW classified ring then we 1998 * don't need to perform this check. 1999 * Perhaps a future optimization. 2000 */ 2001 if (!mac_client_check_flow_vid(mcip, 2002 VLAN_ID(ntohs(evhp->ether_tci)))) { 2003 mac_rx_drop_pkt(mac_srs, mp); 2004 continue; 2005 } 2006 } else { 2007 hdrsize = sizeof (struct ether_header); 2008 } 2009 is_unicast = 2010 ((((uint8_t *)&ehp->ether_dhost)[0] & 0x01) == 0); 2011 dstaddr = (uint8_t *)&ehp->ether_dhost; 2012 } else { 2013 mac_header_info_t mhi; 2014 2015 if (mac_header_info((mac_handle_t)mcip->mci_mip, 2016 mp, &mhi) != 0) { 2017 mac_rx_drop_pkt(mac_srs, mp); 2018 continue; 2019 } 2020 hdrsize = mhi.mhi_hdrsize; 2021 sap = mhi.mhi_bindsap; 2022 is_unicast = (mhi.mhi_dsttype == MAC_ADDRTYPE_UNICAST); 2023 dstaddr = (uint8_t *)mhi.mhi_daddr; 2024 } 2025 2026 if (!dls_bypass) { 2027 if (mac_rx_srs_long_fanout(mac_srs, mp, sap, 2028 hdrsize, &type, &indx) == -1) { 2029 mac_rx_drop_pkt(mac_srs, mp); 2030 continue; 2031 } 2032 2033 FANOUT_ENQUEUE_MP(headmp[type][indx], 2034 tailmp[type][indx], cnt[type][indx], bw_ctl, 2035 sz[type][indx], sz1, mp); 2036 continue; 2037 } 2038 2039 /* 2040 * If we are using the default Rx ring where H/W or S/W 2041 * classification has not happened, we need to verify if 2042 * this unicast packet really belongs to us. 2043 */ 2044 if (sap == ETHERTYPE_IP) { 2045 /* 2046 * If we are H/W classified, but we have promisc 2047 * on, then we need to check for the unicast address. 2048 */ 2049 if (hw_classified && mcip->mci_promisc_list != NULL) { 2050 mac_address_t *map; 2051 2052 rw_enter(&mcip->mci_rw_lock, RW_READER); 2053 map = mcip->mci_unicast; 2054 if (bcmp(dstaddr, map->ma_addr, 2055 map->ma_len) == 0) 2056 type = UNDEF; 2057 rw_exit(&mcip->mci_rw_lock); 2058 } else if (is_unicast) { 2059 type = UNDEF; 2060 } 2061 } 2062 2063 /* 2064 * This needs to become a contract with the driver for 2065 * the fast path. 2066 */ 2067 2068 ipha = (ipha_t *)(mp->b_rptr + hdrsize); 2069 if ((type != OTH) && MBLK_RX_FANOUT_SLOWPATH(mp, ipha)) { 2070 type = OTH; 2071 fanout_oth1++; 2072 } 2073 2074 if (type != OTH) { 2075 uint16_t frag_offset_flags; 2076 2077 switch (ipha->ipha_protocol) { 2078 case IPPROTO_TCP: 2079 case IPPROTO_UDP: 2080 case IPPROTO_SCTP: 2081 case IPPROTO_ESP: 2082 ipha_len = IPH_HDR_LENGTH(ipha); 2083 if ((uchar_t *)ipha + ipha_len + PORTS_SIZE > 2084 mp->b_wptr) { 2085 type = OTH; 2086 break; 2087 } 2088 frag_offset_flags = 2089 ntohs(ipha->ipha_fragment_offset_and_flags); 2090 if ((frag_offset_flags & 2091 (IPH_MF | IPH_OFFSET)) != 0) { 2092 type = OTH; 2093 fanout_oth3++; 2094 break; 2095 } 2096 ports_offset = hdrsize + ipha_len; 2097 break; 2098 default: 2099 type = OTH; 2100 fanout_oth4++; 2101 break; 2102 } 2103 } 2104 2105 if (type == OTH) { 2106 if (mac_rx_srs_long_fanout(mac_srs, mp, sap, 2107 hdrsize, &type, &indx) == -1) { 2108 mac_rx_drop_pkt(mac_srs, mp); 2109 continue; 2110 } 2111 2112 FANOUT_ENQUEUE_MP(headmp[type][indx], 2113 tailmp[type][indx], cnt[type][indx], bw_ctl, 2114 sz[type][indx], sz1, mp); 2115 continue; 2116 } 2117 2118 ASSERT(type == UNDEF); 2119 2120 /* 2121 * XXX-Sunay: We should hold srs_lock since ring_count 2122 * below can change. But if we are always called from 2123 * mac_rx_srs_drain and SRS_PROC is set, then we can 2124 * enforce that ring_count can't be changed i.e. 2125 * to change fanout type or ring count, the calling 2126 * thread needs to be behind SRS_PROC. 2127 */ 2128 switch (ipha->ipha_protocol) { 2129 case IPPROTO_TCP: 2130 /* 2131 * Note that for ESP, we fanout on SPI and it is at the 2132 * same offset as the 2x16-bit ports. So it is clumped 2133 * along with TCP, UDP and SCTP. 2134 */ 2135 hash = HASH_ADDR(ipha->ipha_src, ipha->ipha_dst, 2136 *(uint32_t *)(mp->b_rptr + ports_offset)); 2137 indx = COMPUTE_INDEX(hash, mac_srs->srs_tcp_ring_count); 2138 type = V4_TCP; 2139 mp->b_rptr += hdrsize; 2140 break; 2141 case IPPROTO_UDP: 2142 case IPPROTO_SCTP: 2143 case IPPROTO_ESP: 2144 if (mac_fanout_type == MAC_FANOUT_DEFAULT) { 2145 hash = HASH_ADDR(ipha->ipha_src, ipha->ipha_dst, 2146 *(uint32_t *)(mp->b_rptr + ports_offset)); 2147 indx = COMPUTE_INDEX(hash, 2148 mac_srs->srs_udp_ring_count); 2149 } else { 2150 indx = mac_srs->srs_ind % 2151 mac_srs->srs_udp_ring_count; 2152 mac_srs->srs_ind++; 2153 } 2154 type = V4_UDP; 2155 mp->b_rptr += hdrsize; 2156 break; 2157 default: 2158 indx = 0; 2159 type = OTH; 2160 } 2161 2162 FANOUT_ENQUEUE_MP(headmp[type][indx], tailmp[type][indx], 2163 cnt[type][indx], bw_ctl, sz[type][indx], sz1, mp); 2164 } 2165 2166 for (type = V4_TCP; type < UNDEF; type++) { 2167 int i; 2168 2169 for (i = 0; i < fanout_cnt; i++) { 2170 if (headmp[type][i] != NULL) { 2171 mac_soft_ring_t *softring; 2172 2173 ASSERT(tailmp[type][i]->b_next == NULL); 2174 switch (type) { 2175 case V4_TCP: 2176 softring = 2177 mac_srs->srs_tcp_soft_rings[i]; 2178 break; 2179 case V4_UDP: 2180 softring = 2181 mac_srs->srs_udp_soft_rings[i]; 2182 break; 2183 case OTH: 2184 softring = 2185 mac_srs->srs_oth_soft_rings[i]; 2186 break; 2187 } 2188 mac_rx_soft_ring_process(mcip, 2189 softring, headmp[type][i], tailmp[type][i], 2190 cnt[type][i], sz[type][i]); 2191 } 2192 } 2193 } 2194 } 2195 2196 #define SRS_BYTES_TO_PICKUP 150000 2197 ssize_t max_bytes_to_pickup = SRS_BYTES_TO_PICKUP; 2198 2199 /* 2200 * mac_rx_srs_poll_ring 2201 * 2202 * This SRS Poll thread uses this routine to poll the underlying hardware 2203 * Rx ring to get a chain of packets. It can inline process that chain 2204 * if mac_latency_optimize is set (default) or signal the SRS worker thread 2205 * to do the remaining processing. 2206 * 2207 * Since packets come in the system via interrupt or poll path, we also 2208 * update the stats and deal with promiscous clients here. 2209 */ 2210 void 2211 mac_rx_srs_poll_ring(mac_soft_ring_set_t *mac_srs) 2212 { 2213 kmutex_t *lock = &mac_srs->srs_lock; 2214 kcondvar_t *async = &mac_srs->srs_cv; 2215 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx; 2216 mblk_t *head, *tail, *mp; 2217 callb_cpr_t cprinfo; 2218 ssize_t bytes_to_pickup; 2219 size_t sz; 2220 int count; 2221 mac_client_impl_t *smcip; 2222 2223 CALLB_CPR_INIT(&cprinfo, lock, callb_generic_cpr, "mac_srs_poll"); 2224 mutex_enter(lock); 2225 2226 start: 2227 for (;;) { 2228 if (mac_srs->srs_state & SRS_PAUSE) 2229 goto done; 2230 2231 CALLB_CPR_SAFE_BEGIN(&cprinfo); 2232 cv_wait(async, lock); 2233 CALLB_CPR_SAFE_END(&cprinfo, lock); 2234 2235 if (mac_srs->srs_state & SRS_PAUSE) 2236 goto done; 2237 2238 check_again: 2239 if (mac_srs->srs_type & SRST_BW_CONTROL) { 2240 /* 2241 * We pick as many bytes as we are allowed to queue. 2242 * Its possible that we will exceed the total 2243 * packets queued in case this SRS is part of the 2244 * Rx ring group since > 1 poll thread can be pulling 2245 * upto the max allowed packets at the same time 2246 * but that should be OK. 2247 */ 2248 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2249 bytes_to_pickup = 2250 mac_srs->srs_bw->mac_bw_drop_threshold - 2251 mac_srs->srs_bw->mac_bw_sz; 2252 /* 2253 * We shouldn't have been signalled if we 2254 * have 0 or less bytes to pick but since 2255 * some of the bytes accounting is driver 2256 * dependant, we do the safety check. 2257 */ 2258 if (bytes_to_pickup < 0) 2259 bytes_to_pickup = 0; 2260 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2261 } else { 2262 /* 2263 * ToDO: Need to change the polling API 2264 * to add a packet count and a flag which 2265 * tells the driver whether we want packets 2266 * based on a count, or bytes, or all the 2267 * packets queued in the driver/HW. This 2268 * way, we never have to check the limits 2269 * on poll path. We truly let only as many 2270 * packets enter the system as we are willing 2271 * to process or queue. 2272 * 2273 * Something along the lines of 2274 * pkts_to_pickup = mac_soft_ring_max_q_cnt - 2275 * mac_srs->srs_poll_pkt_cnt 2276 */ 2277 2278 /* 2279 * Since we are not doing B/W control, pick 2280 * as many packets as allowed. 2281 */ 2282 bytes_to_pickup = max_bytes_to_pickup; 2283 } 2284 2285 /* Poll the underlying Hardware */ 2286 mutex_exit(lock); 2287 head = MAC_HWRING_POLL(mac_srs->srs_ring, (int)bytes_to_pickup); 2288 mutex_enter(lock); 2289 2290 ASSERT((mac_srs->srs_state & SRS_POLL_THR_OWNER) == 2291 SRS_POLL_THR_OWNER); 2292 2293 mp = tail = head; 2294 count = 0; 2295 sz = 0; 2296 while (mp != NULL) { 2297 tail = mp; 2298 sz += msgdsize(mp); 2299 mp = mp->b_next; 2300 count++; 2301 } 2302 2303 if (head != NULL) { 2304 tail->b_next = NULL; 2305 smcip = mac_srs->srs_mcip; 2306 2307 SRS_RX_STAT_UPDATE(mac_srs, pollbytes, sz); 2308 SRS_RX_STAT_UPDATE(mac_srs, pollcnt, count); 2309 2310 /* 2311 * If there are any promiscuous mode callbacks 2312 * defined for this MAC client, pass them a copy 2313 * if appropriate and also update the counters. 2314 */ 2315 if (smcip != NULL) { 2316 if (smcip->mci_mip->mi_promisc_list != NULL) { 2317 mutex_exit(lock); 2318 mac_promisc_dispatch(smcip->mci_mip, 2319 head, NULL, B_FALSE); 2320 mutex_enter(lock); 2321 } 2322 } 2323 if (mac_srs->srs_type & SRST_BW_CONTROL) { 2324 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2325 mac_srs->srs_bw->mac_bw_polled += sz; 2326 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2327 } 2328 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, 2329 count, sz); 2330 if (count <= 10) 2331 srs_rx->sr_stat.mrs_chaincntundr10++; 2332 else if (count > 10 && count <= 50) 2333 srs_rx->sr_stat.mrs_chaincnt10to50++; 2334 else 2335 srs_rx->sr_stat.mrs_chaincntover50++; 2336 } 2337 2338 /* 2339 * We are guaranteed that SRS_PROC will be set if we 2340 * are here. Also, poll thread gets to run only if 2341 * the drain was being done by a worker thread although 2342 * its possible that worker thread is still running 2343 * and poll thread was sent down to keep the pipeline 2344 * going instead of doing a complete drain and then 2345 * trying to poll the NIC. 2346 * 2347 * So we need to check SRS_WORKER flag to make sure 2348 * that the worker thread is not processing the queue 2349 * in parallel to us. The flags and conditions are 2350 * protected by the srs_lock to prevent any race. We 2351 * ensure that we don't drop the srs_lock from now 2352 * till the end and similarly we don't drop the srs_lock 2353 * in mac_rx_srs_drain() till similar condition check 2354 * are complete. The mac_rx_srs_drain() needs to ensure 2355 * that SRS_WORKER flag remains set as long as its 2356 * processing the queue. 2357 */ 2358 if (!(mac_srs->srs_state & SRS_WORKER) && 2359 (mac_srs->srs_first != NULL)) { 2360 /* 2361 * We have packets to process and worker thread 2362 * is not running. Check to see if poll thread is 2363 * allowed to process. 2364 */ 2365 if (mac_srs->srs_state & SRS_LATENCY_OPT) { 2366 mac_srs->srs_drain_func(mac_srs, SRS_POLL_PROC); 2367 if (!(mac_srs->srs_state & SRS_PAUSE) && 2368 srs_rx->sr_poll_pkt_cnt <= 2369 srs_rx->sr_lowat) { 2370 srs_rx->sr_poll_again++; 2371 goto check_again; 2372 } 2373 /* 2374 * We are already above low water mark 2375 * so stay in the polling mode but no 2376 * need to poll. Once we dip below 2377 * the polling threshold, the processing 2378 * thread (soft ring) will signal us 2379 * to poll again (MAC_UPDATE_SRS_COUNT) 2380 */ 2381 srs_rx->sr_poll_drain_no_poll++; 2382 mac_srs->srs_state &= ~(SRS_PROC|SRS_GET_PKTS); 2383 /* 2384 * In B/W control case, its possible 2385 * that the backlog built up due to 2386 * B/W limit being reached and packets 2387 * are queued only in SRS. In this case, 2388 * we should schedule worker thread 2389 * since no one else will wake us up. 2390 */ 2391 if ((mac_srs->srs_type & SRST_BW_CONTROL) && 2392 (mac_srs->srs_tid == NULL)) { 2393 mac_srs->srs_tid = 2394 timeout(mac_srs_fire, mac_srs, 1); 2395 srs_rx->sr_poll_worker_wakeup++; 2396 } 2397 } else { 2398 /* 2399 * Wakeup the worker thread for more processing. 2400 * We optimize for throughput in this case. 2401 */ 2402 mac_srs->srs_state &= ~(SRS_PROC|SRS_GET_PKTS); 2403 MAC_SRS_WORKER_WAKEUP(mac_srs); 2404 srs_rx->sr_poll_sig_worker++; 2405 } 2406 } else if ((mac_srs->srs_first == NULL) && 2407 !(mac_srs->srs_state & SRS_WORKER)) { 2408 /* 2409 * There is nothing queued in SRS and 2410 * no worker thread running. Plus we 2411 * didn't get anything from the H/W 2412 * as well (head == NULL); 2413 */ 2414 ASSERT(head == NULL); 2415 mac_srs->srs_state &= 2416 ~(SRS_PROC|SRS_GET_PKTS); 2417 2418 /* 2419 * If we have a packets in soft ring, don't allow 2420 * more packets to come into this SRS by keeping the 2421 * interrupts off but not polling the H/W. The 2422 * poll thread will get signaled as soon as 2423 * srs_poll_pkt_cnt dips below poll threshold. 2424 */ 2425 if (srs_rx->sr_poll_pkt_cnt == 0) { 2426 srs_rx->sr_poll_intr_enable++; 2427 MAC_SRS_POLLING_OFF(mac_srs); 2428 } else { 2429 /* 2430 * We know nothing is queued in SRS 2431 * since we are here after checking 2432 * srs_first is NULL. The backlog 2433 * is entirely due to packets queued 2434 * in Soft ring which will wake us up 2435 * and get the interface out of polling 2436 * mode once the backlog dips below 2437 * sr_poll_thres. 2438 */ 2439 srs_rx->sr_poll_no_poll++; 2440 } 2441 } else { 2442 /* 2443 * Worker thread is already running. 2444 * Nothing much to do. If the polling 2445 * was enabled, worker thread will deal 2446 * with that. 2447 */ 2448 mac_srs->srs_state &= ~SRS_GET_PKTS; 2449 srs_rx->sr_poll_goto_sleep++; 2450 } 2451 } 2452 done: 2453 mac_srs->srs_state |= SRS_POLL_THR_QUIESCED; 2454 cv_signal(&mac_srs->srs_async); 2455 /* 2456 * If this is a temporary quiesce then wait for the restart signal 2457 * from the srs worker. Then clear the flags and signal the srs worker 2458 * to ensure a positive handshake and go back to start. 2459 */ 2460 while (!(mac_srs->srs_state & (SRS_CONDEMNED | SRS_POLL_THR_RESTART))) 2461 cv_wait(async, lock); 2462 if (mac_srs->srs_state & SRS_POLL_THR_RESTART) { 2463 ASSERT(!(mac_srs->srs_state & SRS_CONDEMNED)); 2464 mac_srs->srs_state &= 2465 ~(SRS_POLL_THR_QUIESCED | SRS_POLL_THR_RESTART); 2466 cv_signal(&mac_srs->srs_async); 2467 goto start; 2468 } else { 2469 mac_srs->srs_state |= SRS_POLL_THR_EXITED; 2470 cv_signal(&mac_srs->srs_async); 2471 CALLB_CPR_EXIT(&cprinfo); 2472 thread_exit(); 2473 } 2474 } 2475 2476 /* 2477 * mac_srs_pick_chain 2478 * 2479 * In Bandwidth control case, checks how many packets can be processed 2480 * and return them in a sub chain. 2481 */ 2482 static mblk_t * 2483 mac_srs_pick_chain(mac_soft_ring_set_t *mac_srs, mblk_t **chain_tail, 2484 size_t *chain_sz, int *chain_cnt) 2485 { 2486 mblk_t *head = NULL; 2487 mblk_t *tail = NULL; 2488 size_t sz; 2489 size_t tsz = 0; 2490 int cnt = 0; 2491 mblk_t *mp; 2492 2493 ASSERT(MUTEX_HELD(&mac_srs->srs_lock)); 2494 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2495 if (((mac_srs->srs_bw->mac_bw_used + mac_srs->srs_size) <= 2496 mac_srs->srs_bw->mac_bw_limit) || 2497 (mac_srs->srs_bw->mac_bw_limit == 0)) { 2498 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2499 head = mac_srs->srs_first; 2500 mac_srs->srs_first = NULL; 2501 *chain_tail = mac_srs->srs_last; 2502 mac_srs->srs_last = NULL; 2503 *chain_sz = mac_srs->srs_size; 2504 *chain_cnt = mac_srs->srs_count; 2505 mac_srs->srs_count = 0; 2506 mac_srs->srs_size = 0; 2507 return (head); 2508 } 2509 2510 /* 2511 * Can't clear the entire backlog. 2512 * Need to find how many packets to pick 2513 */ 2514 ASSERT(MUTEX_HELD(&mac_srs->srs_bw->mac_bw_lock)); 2515 while ((mp = mac_srs->srs_first) != NULL) { 2516 sz = msgdsize(mp); 2517 if ((tsz + sz + mac_srs->srs_bw->mac_bw_used) > 2518 mac_srs->srs_bw->mac_bw_limit) { 2519 if (!(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) 2520 mac_srs->srs_bw->mac_bw_state |= 2521 SRS_BW_ENFORCED; 2522 break; 2523 } 2524 2525 /* 2526 * The _size & cnt is decremented from the softrings 2527 * when they send up the packet for polling to work 2528 * properly. 2529 */ 2530 tsz += sz; 2531 cnt++; 2532 mac_srs->srs_count--; 2533 mac_srs->srs_size -= sz; 2534 if (tail != NULL) 2535 tail->b_next = mp; 2536 else 2537 head = mp; 2538 tail = mp; 2539 mac_srs->srs_first = mac_srs->srs_first->b_next; 2540 } 2541 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2542 if (mac_srs->srs_first == NULL) 2543 mac_srs->srs_last = NULL; 2544 2545 if (tail != NULL) 2546 tail->b_next = NULL; 2547 *chain_tail = tail; 2548 *chain_cnt = cnt; 2549 *chain_sz = tsz; 2550 2551 return (head); 2552 } 2553 2554 /* 2555 * mac_rx_srs_drain 2556 * 2557 * The SRS drain routine. Gets to run to clear the queue. Any thread 2558 * (worker, interrupt, poll) can call this based on processing model. 2559 * The first thing we do is disable interrupts if possible and then 2560 * drain the queue. we also try to poll the underlying hardware if 2561 * there is a dedicated hardware Rx ring assigned to this SRS. 2562 * 2563 * There is a equivalent drain routine in bandwidth control mode 2564 * mac_rx_srs_drain_bw. There is some code duplication between the two 2565 * routines but they are highly performance sensitive and are easier 2566 * to read/debug if they stay separate. Any code changes here might 2567 * also apply to mac_rx_srs_drain_bw as well. 2568 */ 2569 void 2570 mac_rx_srs_drain(mac_soft_ring_set_t *mac_srs, uint_t proc_type) 2571 { 2572 mblk_t *head; 2573 mblk_t *tail; 2574 timeout_id_t tid; 2575 int cnt = 0; 2576 mac_client_impl_t *mcip = mac_srs->srs_mcip; 2577 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx; 2578 2579 ASSERT(MUTEX_HELD(&mac_srs->srs_lock)); 2580 ASSERT(!(mac_srs->srs_type & SRST_BW_CONTROL)); 2581 2582 /* If we are blanked i.e. can't do upcalls, then we are done */ 2583 if (mac_srs->srs_state & (SRS_BLANK | SRS_PAUSE)) { 2584 ASSERT((mac_srs->srs_type & SRST_NO_SOFT_RINGS) || 2585 (mac_srs->srs_state & SRS_PAUSE)); 2586 goto out; 2587 } 2588 2589 if (mac_srs->srs_first == NULL) 2590 goto out; 2591 2592 if (!(mac_srs->srs_state & SRS_LATENCY_OPT) && 2593 (srs_rx->sr_poll_pkt_cnt <= srs_rx->sr_lowat)) { 2594 /* 2595 * In the normal case, the SRS worker thread does no 2596 * work and we wait for a backlog to build up before 2597 * we switch into polling mode. In case we are 2598 * optimizing for throughput, we use the worker thread 2599 * as well. The goal is to let worker thread process 2600 * the queue and poll thread to feed packets into 2601 * the queue. As such, we should signal the poll 2602 * thread to try and get more packets. 2603 * 2604 * We could have pulled this check in the POLL_RING 2605 * macro itself but keeping it explicit here makes 2606 * the architecture more human understandable. 2607 */ 2608 MAC_SRS_POLL_RING(mac_srs); 2609 } 2610 2611 again: 2612 head = mac_srs->srs_first; 2613 mac_srs->srs_first = NULL; 2614 tail = mac_srs->srs_last; 2615 mac_srs->srs_last = NULL; 2616 cnt = mac_srs->srs_count; 2617 mac_srs->srs_count = 0; 2618 2619 ASSERT(head != NULL); 2620 ASSERT(tail != NULL); 2621 2622 if ((tid = mac_srs->srs_tid) != NULL) 2623 mac_srs->srs_tid = NULL; 2624 2625 mac_srs->srs_state |= (SRS_PROC|proc_type); 2626 2627 /* 2628 * mcip is NULL for broadcast and multicast flows. The promisc 2629 * callbacks for broadcast and multicast packets are delivered from 2630 * mac_rx() and we don't need to worry about that case in this path 2631 */ 2632 if (mcip != NULL) { 2633 if (mcip->mci_promisc_list != NULL) { 2634 mutex_exit(&mac_srs->srs_lock); 2635 mac_promisc_client_dispatch(mcip, head); 2636 mutex_enter(&mac_srs->srs_lock); 2637 } 2638 if (MAC_PROTECT_ENABLED(mcip, MPT_IPNOSPOOF)) { 2639 mutex_exit(&mac_srs->srs_lock); 2640 mac_protect_intercept_dynamic(mcip, head); 2641 mutex_enter(&mac_srs->srs_lock); 2642 } 2643 } 2644 2645 /* 2646 * Check if SRS itself is doing the processing. This direct 2647 * path applies only when subflows are present. 2648 */ 2649 if (mac_srs->srs_type & SRST_NO_SOFT_RINGS) { 2650 mac_direct_rx_t proc; 2651 void *arg1; 2652 mac_resource_handle_t arg2; 2653 2654 /* 2655 * This is the case when a Rx is directly 2656 * assigned and we have a fully classified 2657 * protocol chain. We can deal with it in 2658 * one shot. 2659 */ 2660 proc = srs_rx->sr_func; 2661 arg1 = srs_rx->sr_arg1; 2662 arg2 = srs_rx->sr_arg2; 2663 2664 mac_srs->srs_state |= SRS_CLIENT_PROC; 2665 mutex_exit(&mac_srs->srs_lock); 2666 if (tid != NULL) { 2667 (void) untimeout(tid); 2668 tid = NULL; 2669 } 2670 2671 proc(arg1, arg2, head, NULL); 2672 /* 2673 * Decrement the size and count here itelf 2674 * since the packet has been processed. 2675 */ 2676 mutex_enter(&mac_srs->srs_lock); 2677 MAC_UPDATE_SRS_COUNT_LOCKED(mac_srs, cnt); 2678 if (mac_srs->srs_state & SRS_CLIENT_WAIT) 2679 cv_signal(&mac_srs->srs_client_cv); 2680 mac_srs->srs_state &= ~SRS_CLIENT_PROC; 2681 } else { 2682 /* Some kind of softrings based fanout is required */ 2683 mutex_exit(&mac_srs->srs_lock); 2684 if (tid != NULL) { 2685 (void) untimeout(tid); 2686 tid = NULL; 2687 } 2688 2689 /* 2690 * Since the fanout routines can deal with chains, 2691 * shoot the entire chain up. 2692 */ 2693 if (mac_srs->srs_type & SRST_FANOUT_SRC_IP) 2694 mac_rx_srs_fanout(mac_srs, head); 2695 else 2696 mac_rx_srs_proto_fanout(mac_srs, head); 2697 mutex_enter(&mac_srs->srs_lock); 2698 } 2699 2700 if (!(mac_srs->srs_state & (SRS_BLANK|SRS_PAUSE)) && 2701 (mac_srs->srs_first != NULL)) { 2702 /* 2703 * More packets arrived while we were clearing the 2704 * SRS. This can be possible because of one of 2705 * three conditions below: 2706 * 1) The driver is using multiple worker threads 2707 * to send the packets to us. 2708 * 2) The driver has a race in switching 2709 * between interrupt and polling mode or 2710 * 3) Packets are arriving in this SRS via the 2711 * S/W classification as well. 2712 * 2713 * We should switch to polling mode and see if we 2714 * need to send the poll thread down. Also, signal 2715 * the worker thread to process whats just arrived. 2716 */ 2717 MAC_SRS_POLLING_ON(mac_srs); 2718 if (srs_rx->sr_poll_pkt_cnt <= srs_rx->sr_lowat) { 2719 srs_rx->sr_drain_poll_sig++; 2720 MAC_SRS_POLL_RING(mac_srs); 2721 } 2722 2723 /* 2724 * If we didn't signal the poll thread, we need 2725 * to deal with the pending packets ourselves. 2726 */ 2727 if (proc_type == SRS_WORKER) { 2728 srs_rx->sr_drain_again++; 2729 goto again; 2730 } else { 2731 srs_rx->sr_drain_worker_sig++; 2732 cv_signal(&mac_srs->srs_async); 2733 } 2734 } 2735 2736 out: 2737 if (mac_srs->srs_state & SRS_GET_PKTS) { 2738 /* 2739 * Poll thread is already running. Leave the 2740 * SRS_RPOC set and hand over the control to 2741 * poll thread. 2742 */ 2743 mac_srs->srs_state &= ~proc_type; 2744 srs_rx->sr_drain_poll_running++; 2745 return; 2746 } 2747 2748 /* 2749 * Even if there are no packets queued in SRS, we 2750 * need to make sure that the shared counter is 2751 * clear and any associated softrings have cleared 2752 * all the backlog. Otherwise, leave the interface 2753 * in polling mode and the poll thread will get 2754 * signalled once the count goes down to zero. 2755 * 2756 * If someone is already draining the queue (SRS_PROC is 2757 * set) when the srs_poll_pkt_cnt goes down to zero, 2758 * then it means that drain is already running and we 2759 * will turn off polling at that time if there is 2760 * no backlog. 2761 * 2762 * As long as there are packets queued either 2763 * in soft ring set or its soft rings, we will leave 2764 * the interface in polling mode (even if the drain 2765 * was done being the interrupt thread). We signal 2766 * the poll thread as well if we have dipped below 2767 * low water mark. 2768 * 2769 * NOTE: We can't use the MAC_SRS_POLLING_ON macro 2770 * since that turn polling on only for worker thread. 2771 * Its not worth turning polling on for interrupt 2772 * thread (since NIC will not issue another interrupt) 2773 * unless a backlog builds up. 2774 */ 2775 if ((srs_rx->sr_poll_pkt_cnt > 0) && 2776 (mac_srs->srs_state & SRS_POLLING_CAPAB)) { 2777 mac_srs->srs_state &= ~(SRS_PROC|proc_type); 2778 srs_rx->sr_drain_keep_polling++; 2779 MAC_SRS_POLLING_ON(mac_srs); 2780 if (srs_rx->sr_poll_pkt_cnt <= srs_rx->sr_lowat) 2781 MAC_SRS_POLL_RING(mac_srs); 2782 return; 2783 } 2784 2785 /* Nothing else to do. Get out of poll mode */ 2786 MAC_SRS_POLLING_OFF(mac_srs); 2787 mac_srs->srs_state &= ~(SRS_PROC|proc_type); 2788 srs_rx->sr_drain_finish_intr++; 2789 } 2790 2791 /* 2792 * mac_rx_srs_drain_bw 2793 * 2794 * The SRS BW drain routine. Gets to run to clear the queue. Any thread 2795 * (worker, interrupt, poll) can call this based on processing model. 2796 * The first thing we do is disable interrupts if possible and then 2797 * drain the queue. we also try to poll the underlying hardware if 2798 * there is a dedicated hardware Rx ring assigned to this SRS. 2799 * 2800 * There is a equivalent drain routine in non bandwidth control mode 2801 * mac_rx_srs_drain. There is some code duplication between the two 2802 * routines but they are highly performance sensitive and are easier 2803 * to read/debug if they stay separate. Any code changes here might 2804 * also apply to mac_rx_srs_drain as well. 2805 */ 2806 void 2807 mac_rx_srs_drain_bw(mac_soft_ring_set_t *mac_srs, uint_t proc_type) 2808 { 2809 mblk_t *head; 2810 mblk_t *tail; 2811 timeout_id_t tid; 2812 size_t sz = 0; 2813 int cnt = 0; 2814 mac_client_impl_t *mcip = mac_srs->srs_mcip; 2815 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx; 2816 clock_t now; 2817 2818 ASSERT(MUTEX_HELD(&mac_srs->srs_lock)); 2819 ASSERT(mac_srs->srs_type & SRST_BW_CONTROL); 2820 again: 2821 /* Check if we are doing B/W control */ 2822 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2823 now = ddi_get_lbolt(); 2824 if (mac_srs->srs_bw->mac_bw_curr_time != now) { 2825 mac_srs->srs_bw->mac_bw_curr_time = now; 2826 mac_srs->srs_bw->mac_bw_used = 0; 2827 if (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) 2828 mac_srs->srs_bw->mac_bw_state &= ~SRS_BW_ENFORCED; 2829 } else if (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) { 2830 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2831 goto done; 2832 } else if (mac_srs->srs_bw->mac_bw_used > 2833 mac_srs->srs_bw->mac_bw_limit) { 2834 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED; 2835 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2836 goto done; 2837 } 2838 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2839 2840 /* If we are blanked i.e. can't do upcalls, then we are done */ 2841 if (mac_srs->srs_state & (SRS_BLANK | SRS_PAUSE)) { 2842 ASSERT((mac_srs->srs_type & SRST_NO_SOFT_RINGS) || 2843 (mac_srs->srs_state & SRS_PAUSE)); 2844 goto done; 2845 } 2846 2847 sz = 0; 2848 cnt = 0; 2849 if ((head = mac_srs_pick_chain(mac_srs, &tail, &sz, &cnt)) == NULL) { 2850 /* 2851 * We couldn't pick up a single packet. 2852 */ 2853 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2854 if ((mac_srs->srs_bw->mac_bw_used == 0) && 2855 (mac_srs->srs_size != 0) && 2856 !(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) { 2857 /* 2858 * Seems like configured B/W doesn't 2859 * even allow processing of 1 packet 2860 * per tick. 2861 * 2862 * XXX: raise the limit to processing 2863 * at least 1 packet per tick. 2864 */ 2865 mac_srs->srs_bw->mac_bw_limit += 2866 mac_srs->srs_bw->mac_bw_limit; 2867 mac_srs->srs_bw->mac_bw_drop_threshold += 2868 mac_srs->srs_bw->mac_bw_drop_threshold; 2869 cmn_err(CE_NOTE, "mac_rx_srs_drain: srs(%p) " 2870 "raised B/W limit to %d since not even a " 2871 "single packet can be processed per " 2872 "tick %d\n", (void *)mac_srs, 2873 (int)mac_srs->srs_bw->mac_bw_limit, 2874 (int)msgdsize(mac_srs->srs_first)); 2875 } 2876 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2877 goto done; 2878 } 2879 2880 ASSERT(head != NULL); 2881 ASSERT(tail != NULL); 2882 2883 /* zero bandwidth: drop all and return to interrupt mode */ 2884 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2885 if (mac_srs->srs_bw->mac_bw_limit == 0) { 2886 srs_rx->sr_stat.mrs_sdrops += cnt; 2887 ASSERT(mac_srs->srs_bw->mac_bw_sz >= sz); 2888 mac_srs->srs_bw->mac_bw_sz -= sz; 2889 mac_srs->srs_bw->mac_bw_drop_bytes += sz; 2890 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2891 mac_drop_chain(head, "Rx no bandwidth"); 2892 goto leave_poll; 2893 } else { 2894 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2895 } 2896 2897 if ((tid = mac_srs->srs_tid) != NULL) 2898 mac_srs->srs_tid = NULL; 2899 2900 mac_srs->srs_state |= (SRS_PROC|proc_type); 2901 MAC_SRS_WORKER_POLLING_ON(mac_srs); 2902 2903 /* 2904 * mcip is NULL for broadcast and multicast flows. The promisc 2905 * callbacks for broadcast and multicast packets are delivered from 2906 * mac_rx() and we don't need to worry about that case in this path 2907 */ 2908 if (mcip != NULL) { 2909 if (mcip->mci_promisc_list != NULL) { 2910 mutex_exit(&mac_srs->srs_lock); 2911 mac_promisc_client_dispatch(mcip, head); 2912 mutex_enter(&mac_srs->srs_lock); 2913 } 2914 if (MAC_PROTECT_ENABLED(mcip, MPT_IPNOSPOOF)) { 2915 mutex_exit(&mac_srs->srs_lock); 2916 mac_protect_intercept_dynamic(mcip, head); 2917 mutex_enter(&mac_srs->srs_lock); 2918 } 2919 } 2920 2921 /* 2922 * Check if SRS itself is doing the processing 2923 * This direct path does not apply when subflows are present. In this 2924 * case, packets need to be dispatched to a soft ring according to the 2925 * flow's bandwidth and other resources contraints. 2926 */ 2927 if (mac_srs->srs_type & SRST_NO_SOFT_RINGS) { 2928 mac_direct_rx_t proc; 2929 void *arg1; 2930 mac_resource_handle_t arg2; 2931 2932 /* 2933 * This is the case when a Rx is directly 2934 * assigned and we have a fully classified 2935 * protocol chain. We can deal with it in 2936 * one shot. 2937 */ 2938 proc = srs_rx->sr_func; 2939 arg1 = srs_rx->sr_arg1; 2940 arg2 = srs_rx->sr_arg2; 2941 2942 mac_srs->srs_state |= SRS_CLIENT_PROC; 2943 mutex_exit(&mac_srs->srs_lock); 2944 if (tid != NULL) { 2945 (void) untimeout(tid); 2946 tid = NULL; 2947 } 2948 2949 proc(arg1, arg2, head, NULL); 2950 /* 2951 * Decrement the size and count here itelf 2952 * since the packet has been processed. 2953 */ 2954 mutex_enter(&mac_srs->srs_lock); 2955 MAC_UPDATE_SRS_COUNT_LOCKED(mac_srs, cnt); 2956 MAC_UPDATE_SRS_SIZE_LOCKED(mac_srs, sz); 2957 2958 if (mac_srs->srs_state & SRS_CLIENT_WAIT) 2959 cv_signal(&mac_srs->srs_client_cv); 2960 mac_srs->srs_state &= ~SRS_CLIENT_PROC; 2961 } else { 2962 /* Some kind of softrings based fanout is required */ 2963 mutex_exit(&mac_srs->srs_lock); 2964 if (tid != NULL) { 2965 (void) untimeout(tid); 2966 tid = NULL; 2967 } 2968 2969 /* 2970 * Since the fanout routines can deal with chains, 2971 * shoot the entire chain up. 2972 */ 2973 if (mac_srs->srs_type & SRST_FANOUT_SRC_IP) 2974 mac_rx_srs_fanout(mac_srs, head); 2975 else 2976 mac_rx_srs_proto_fanout(mac_srs, head); 2977 mutex_enter(&mac_srs->srs_lock); 2978 } 2979 2980 /* 2981 * Send the poll thread to pick up any packets arrived 2982 * so far. This also serves as the last check in case 2983 * nothing else is queued in the SRS. The poll thread 2984 * is signalled only in the case the drain was done 2985 * by the worker thread and SRS_WORKER is set. The 2986 * worker thread can run in parallel as long as the 2987 * SRS_WORKER flag is set. We we have nothing else to 2988 * process, we can exit while leaving SRS_PROC set 2989 * which gives the poll thread control to process and 2990 * cleanup once it returns from the NIC. 2991 * 2992 * If we have nothing else to process, we need to 2993 * ensure that we keep holding the srs_lock till 2994 * all the checks below are done and control is 2995 * handed to the poll thread if it was running. 2996 */ 2997 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2998 if (!(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) { 2999 if (mac_srs->srs_first != NULL) { 3000 if (proc_type == SRS_WORKER) { 3001 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 3002 if (srs_rx->sr_poll_pkt_cnt <= 3003 srs_rx->sr_lowat) 3004 MAC_SRS_POLL_RING(mac_srs); 3005 goto again; 3006 } else { 3007 cv_signal(&mac_srs->srs_async); 3008 } 3009 } 3010 } 3011 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 3012 3013 done: 3014 3015 if (mac_srs->srs_state & SRS_GET_PKTS) { 3016 /* 3017 * Poll thread is already running. Leave the 3018 * SRS_RPOC set and hand over the control to 3019 * poll thread. 3020 */ 3021 mac_srs->srs_state &= ~proc_type; 3022 return; 3023 } 3024 3025 /* 3026 * If we can't process packets because we have exceeded 3027 * B/W limit for this tick, just set the timeout 3028 * and leave. 3029 * 3030 * Even if there are no packets queued in SRS, we 3031 * need to make sure that the shared counter is 3032 * clear and any associated softrings have cleared 3033 * all the backlog. Otherwise, leave the interface 3034 * in polling mode and the poll thread will get 3035 * signalled once the count goes down to zero. 3036 * 3037 * If someone is already draining the queue (SRS_PROC is 3038 * set) when the srs_poll_pkt_cnt goes down to zero, 3039 * then it means that drain is already running and we 3040 * will turn off polling at that time if there is 3041 * no backlog. As long as there are packets queued either 3042 * is soft ring set or its soft rings, we will leave 3043 * the interface in polling mode. 3044 */ 3045 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 3046 if ((mac_srs->srs_state & SRS_POLLING_CAPAB) && 3047 ((mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) || 3048 (srs_rx->sr_poll_pkt_cnt > 0))) { 3049 MAC_SRS_POLLING_ON(mac_srs); 3050 mac_srs->srs_state &= ~(SRS_PROC|proc_type); 3051 if ((mac_srs->srs_first != NULL) && 3052 (mac_srs->srs_tid == NULL)) 3053 mac_srs->srs_tid = timeout(mac_srs_fire, 3054 mac_srs, 1); 3055 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 3056 return; 3057 } 3058 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 3059 3060 leave_poll: 3061 3062 /* Nothing else to do. Get out of poll mode */ 3063 MAC_SRS_POLLING_OFF(mac_srs); 3064 mac_srs->srs_state &= ~(SRS_PROC|proc_type); 3065 } 3066 3067 /* 3068 * mac_srs_worker 3069 * 3070 * The SRS worker routine. Drains the queue when no one else is 3071 * processing it. 3072 */ 3073 void 3074 mac_srs_worker(mac_soft_ring_set_t *mac_srs) 3075 { 3076 kmutex_t *lock = &mac_srs->srs_lock; 3077 kcondvar_t *async = &mac_srs->srs_async; 3078 callb_cpr_t cprinfo; 3079 boolean_t bw_ctl_flag; 3080 3081 CALLB_CPR_INIT(&cprinfo, lock, callb_generic_cpr, "srs_worker"); 3082 mutex_enter(lock); 3083 3084 start: 3085 for (;;) { 3086 bw_ctl_flag = B_FALSE; 3087 if (mac_srs->srs_type & SRST_BW_CONTROL) { 3088 MAC_SRS_BW_LOCK(mac_srs); 3089 MAC_SRS_CHECK_BW_CONTROL(mac_srs); 3090 if (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) 3091 bw_ctl_flag = B_TRUE; 3092 MAC_SRS_BW_UNLOCK(mac_srs); 3093 } 3094 /* 3095 * The SRS_BW_ENFORCED flag may change since we have dropped 3096 * the mac_bw_lock. However the drain function can handle both 3097 * a drainable SRS or a bandwidth controlled SRS, and the 3098 * effect of scheduling a timeout is to wakeup the worker 3099 * thread which in turn will call the drain function. Since 3100 * we release the srs_lock atomically only in the cv_wait there 3101 * isn't a fear of waiting for ever. 3102 */ 3103 while (((mac_srs->srs_state & SRS_PROC) || 3104 (mac_srs->srs_first == NULL) || bw_ctl_flag || 3105 (mac_srs->srs_state & SRS_TX_BLOCKED)) && 3106 !(mac_srs->srs_state & SRS_PAUSE)) { 3107 /* 3108 * If we have packets queued and we are here 3109 * because B/W control is in place, we better 3110 * schedule the worker wakeup after 1 tick 3111 * to see if bandwidth control can be relaxed. 3112 */ 3113 if (bw_ctl_flag && mac_srs->srs_tid == NULL) { 3114 /* 3115 * We need to ensure that a timer is already 3116 * scheduled or we force schedule one for 3117 * later so that we can continue processing 3118 * after this quanta is over. 3119 */ 3120 mac_srs->srs_tid = timeout(mac_srs_fire, 3121 mac_srs, 1); 3122 } 3123 wait: 3124 CALLB_CPR_SAFE_BEGIN(&cprinfo); 3125 cv_wait(async, lock); 3126 CALLB_CPR_SAFE_END(&cprinfo, lock); 3127 3128 if (mac_srs->srs_state & SRS_PAUSE) 3129 goto done; 3130 if (mac_srs->srs_state & SRS_PROC) 3131 goto wait; 3132 3133 if (mac_srs->srs_first != NULL && 3134 mac_srs->srs_type & SRST_BW_CONTROL) { 3135 MAC_SRS_BW_LOCK(mac_srs); 3136 if (mac_srs->srs_bw->mac_bw_state & 3137 SRS_BW_ENFORCED) { 3138 MAC_SRS_CHECK_BW_CONTROL(mac_srs); 3139 } 3140 bw_ctl_flag = mac_srs->srs_bw->mac_bw_state & 3141 SRS_BW_ENFORCED; 3142 MAC_SRS_BW_UNLOCK(mac_srs); 3143 } 3144 } 3145 3146 if (mac_srs->srs_state & SRS_PAUSE) 3147 goto done; 3148 mac_srs->srs_drain_func(mac_srs, SRS_WORKER); 3149 } 3150 done: 3151 /* 3152 * The Rx SRS quiesce logic first cuts off packet supply to the SRS 3153 * from both hard and soft classifications and waits for such threads 3154 * to finish before signaling the worker. So at this point the only 3155 * thread left that could be competing with the worker is the poll 3156 * thread. In the case of Tx, there shouldn't be any thread holding 3157 * SRS_PROC at this point. 3158 */ 3159 if (!(mac_srs->srs_state & SRS_PROC)) { 3160 mac_srs->srs_state |= SRS_PROC; 3161 } else { 3162 ASSERT((mac_srs->srs_type & SRST_TX) == 0); 3163 /* 3164 * Poll thread still owns the SRS and is still running 3165 */ 3166 ASSERT((mac_srs->srs_poll_thr == NULL) || 3167 ((mac_srs->srs_state & SRS_POLL_THR_OWNER) == 3168 SRS_POLL_THR_OWNER)); 3169 } 3170 mac_srs_worker_quiesce(mac_srs); 3171 /* 3172 * Wait for the SRS_RESTART or SRS_CONDEMNED signal from the initiator 3173 * of the quiesce operation 3174 */ 3175 while (!(mac_srs->srs_state & (SRS_CONDEMNED | SRS_RESTART))) 3176 cv_wait(&mac_srs->srs_async, &mac_srs->srs_lock); 3177 3178 if (mac_srs->srs_state & SRS_RESTART) { 3179 ASSERT(!(mac_srs->srs_state & SRS_CONDEMNED)); 3180 mac_srs_worker_restart(mac_srs); 3181 mac_srs->srs_state &= ~SRS_PROC; 3182 goto start; 3183 } 3184 3185 if (!(mac_srs->srs_state & SRS_CONDEMNED_DONE)) 3186 mac_srs_worker_quiesce(mac_srs); 3187 3188 mac_srs->srs_state &= ~SRS_PROC; 3189 /* The macro drops the srs_lock */ 3190 CALLB_CPR_EXIT(&cprinfo); 3191 thread_exit(); 3192 } 3193 3194 /* 3195 * mac_rx_srs_subflow_process 3196 * 3197 * Receive side routine called from interrupt path when there are 3198 * sub flows present on this SRS. 3199 */ 3200 /* ARGSUSED */ 3201 void 3202 mac_rx_srs_subflow_process(void *arg, mac_resource_handle_t srs, 3203 mblk_t *mp_chain, boolean_t loopback) 3204 { 3205 flow_entry_t *flent = NULL; 3206 flow_entry_t *prev_flent = NULL; 3207 mblk_t *mp = NULL; 3208 mblk_t *tail = NULL; 3209 mac_soft_ring_set_t *mac_srs = (mac_soft_ring_set_t *)srs; 3210 mac_client_impl_t *mcip; 3211 3212 mcip = mac_srs->srs_mcip; 3213 ASSERT(mcip != NULL); 3214 3215 /* 3216 * We need to determine the SRS for every packet 3217 * by walking the flow table, if we don't get any, 3218 * then we proceed using the SRS we came with. 3219 */ 3220 mp = tail = mp_chain; 3221 while (mp != NULL) { 3222 3223 /* 3224 * We will increment the stats for the matching subflow. 3225 * when we get the bytes/pkt count for the classified packets 3226 * later in mac_rx_srs_process. 3227 */ 3228 (void) mac_flow_lookup(mcip->mci_subflow_tab, mp, 3229 FLOW_INBOUND, &flent); 3230 3231 if (mp == mp_chain || flent == prev_flent) { 3232 if (prev_flent != NULL) 3233 FLOW_REFRELE(prev_flent); 3234 prev_flent = flent; 3235 flent = NULL; 3236 tail = mp; 3237 mp = mp->b_next; 3238 continue; 3239 } 3240 tail->b_next = NULL; 3241 /* 3242 * A null indicates, this is for the mac_srs itself. 3243 * XXX-venu : probably assert for fe_rx_srs_cnt == 0. 3244 */ 3245 if (prev_flent == NULL || prev_flent->fe_rx_srs_cnt == 0) { 3246 mac_rx_srs_process(arg, 3247 (mac_resource_handle_t)mac_srs, mp_chain, 3248 loopback); 3249 } else { 3250 (prev_flent->fe_cb_fn)(prev_flent->fe_cb_arg1, 3251 prev_flent->fe_cb_arg2, mp_chain, loopback); 3252 FLOW_REFRELE(prev_flent); 3253 } 3254 prev_flent = flent; 3255 flent = NULL; 3256 mp_chain = mp; 3257 tail = mp; 3258 mp = mp->b_next; 3259 } 3260 /* Last chain */ 3261 ASSERT(mp_chain != NULL); 3262 if (prev_flent == NULL || prev_flent->fe_rx_srs_cnt == 0) { 3263 mac_rx_srs_process(arg, 3264 (mac_resource_handle_t)mac_srs, mp_chain, loopback); 3265 } else { 3266 (prev_flent->fe_cb_fn)(prev_flent->fe_cb_arg1, 3267 prev_flent->fe_cb_arg2, mp_chain, loopback); 3268 FLOW_REFRELE(prev_flent); 3269 } 3270 } 3271 3272 /* 3273 * MAC SRS receive side routine. If the data is coming from the 3274 * network (i.e. from a NIC) then this is called in interrupt context. 3275 * If the data is coming from a local sender (e.g. mac_tx_send() or 3276 * bridge_forward()) then this is not called in interrupt context. 3277 * 3278 * loopback is set to force a context switch on the loopback 3279 * path between MAC clients. 3280 */ 3281 /* ARGSUSED */ 3282 void 3283 mac_rx_srs_process(void *arg, mac_resource_handle_t srs, mblk_t *mp_chain, 3284 boolean_t loopback) 3285 { 3286 mac_soft_ring_set_t *mac_srs = (mac_soft_ring_set_t *)srs; 3287 mblk_t *mp, *tail, *head; 3288 int count = 0; 3289 int count1; 3290 size_t sz = 0; 3291 size_t chain_sz, sz1; 3292 mac_bw_ctl_t *mac_bw; 3293 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx; 3294 3295 /* 3296 * Set the tail, count and sz. We set the sz irrespective 3297 * of whether we are doing B/W control or not for the 3298 * purpose of updating the stats. 3299 */ 3300 mp = tail = mp_chain; 3301 while (mp != NULL) { 3302 tail = mp; 3303 count++; 3304 sz += msgdsize(mp); 3305 mp = mp->b_next; 3306 } 3307 3308 mutex_enter(&mac_srs->srs_lock); 3309 3310 if (loopback) { 3311 SRS_RX_STAT_UPDATE(mac_srs, lclbytes, sz); 3312 SRS_RX_STAT_UPDATE(mac_srs, lclcnt, count); 3313 3314 } else { 3315 SRS_RX_STAT_UPDATE(mac_srs, intrbytes, sz); 3316 SRS_RX_STAT_UPDATE(mac_srs, intrcnt, count); 3317 } 3318 3319 /* 3320 * If the SRS in already being processed; has been blanked; 3321 * can be processed by worker thread only; or the B/W limit 3322 * has been reached, then queue the chain and check if 3323 * worker thread needs to be awakend. 3324 */ 3325 if (mac_srs->srs_type & SRST_BW_CONTROL) { 3326 mac_bw = mac_srs->srs_bw; 3327 ASSERT(mac_bw != NULL); 3328 mutex_enter(&mac_bw->mac_bw_lock); 3329 mac_bw->mac_bw_intr += sz; 3330 if (mac_bw->mac_bw_limit == 0) { 3331 /* zero bandwidth: drop all */ 3332 srs_rx->sr_stat.mrs_sdrops += count; 3333 mac_bw->mac_bw_drop_bytes += sz; 3334 mutex_exit(&mac_bw->mac_bw_lock); 3335 mutex_exit(&mac_srs->srs_lock); 3336 mac_drop_chain(mp_chain, "Rx no bandwidth"); 3337 return; 3338 } else { 3339 if ((mac_bw->mac_bw_sz + sz) <= 3340 mac_bw->mac_bw_drop_threshold) { 3341 mutex_exit(&mac_bw->mac_bw_lock); 3342 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, mp_chain, 3343 tail, count, sz); 3344 } else { 3345 mp = mp_chain; 3346 chain_sz = 0; 3347 count1 = 0; 3348 tail = NULL; 3349 head = NULL; 3350 while (mp != NULL) { 3351 sz1 = msgdsize(mp); 3352 if (mac_bw->mac_bw_sz + chain_sz + sz1 > 3353 mac_bw->mac_bw_drop_threshold) 3354 break; 3355 chain_sz += sz1; 3356 count1++; 3357 tail = mp; 3358 mp = mp->b_next; 3359 } 3360 mutex_exit(&mac_bw->mac_bw_lock); 3361 if (tail != NULL) { 3362 head = tail->b_next; 3363 tail->b_next = NULL; 3364 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, 3365 mp_chain, tail, count1, chain_sz); 3366 sz -= chain_sz; 3367 count -= count1; 3368 } else { 3369 /* Can't pick up any */ 3370 head = mp_chain; 3371 } 3372 if (head != NULL) { 3373 /* Drop any packet over the threshold */ 3374 srs_rx->sr_stat.mrs_sdrops += count; 3375 mutex_enter(&mac_bw->mac_bw_lock); 3376 mac_bw->mac_bw_drop_bytes += sz; 3377 mutex_exit(&mac_bw->mac_bw_lock); 3378 freemsgchain(head); 3379 } 3380 } 3381 MAC_SRS_WORKER_WAKEUP(mac_srs); 3382 mutex_exit(&mac_srs->srs_lock); 3383 return; 3384 } 3385 } 3386 3387 /* 3388 * If the total number of packets queued in the SRS and 3389 * its associated soft rings exceeds the max allowed, 3390 * then drop the chain. If we are polling capable, this 3391 * shouldn't be happening. 3392 */ 3393 if (!(mac_srs->srs_type & SRST_BW_CONTROL) && 3394 (srs_rx->sr_poll_pkt_cnt > srs_rx->sr_hiwat)) { 3395 mac_bw = mac_srs->srs_bw; 3396 srs_rx->sr_stat.mrs_sdrops += count; 3397 mutex_enter(&mac_bw->mac_bw_lock); 3398 mac_bw->mac_bw_drop_bytes += sz; 3399 mutex_exit(&mac_bw->mac_bw_lock); 3400 freemsgchain(mp_chain); 3401 mutex_exit(&mac_srs->srs_lock); 3402 return; 3403 } 3404 3405 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, mp_chain, tail, count, sz); 3406 3407 if (!(mac_srs->srs_state & SRS_PROC)) { 3408 /* 3409 * If we are coming via loopback, if we are not optimizing for 3410 * latency, or if our stack is running deep, we should signal 3411 * the worker thread. 3412 */ 3413 if (loopback || !(mac_srs->srs_state & SRS_LATENCY_OPT)) { 3414 /* 3415 * For loopback, We need to let the worker take 3416 * over as we don't want to continue in the same 3417 * thread even if we can. This could lead to stack 3418 * overflows and may also end up using 3419 * resources (cpu) incorrectly. 3420 */ 3421 cv_signal(&mac_srs->srs_async); 3422 } else if (STACK_BIAS + (uintptr_t)getfp() - 3423 (uintptr_t)curthread->t_stkbase < mac_rx_srs_stack_needed) { 3424 if (++mac_rx_srs_stack_toodeep == 0) 3425 mac_rx_srs_stack_toodeep = 1; 3426 cv_signal(&mac_srs->srs_async); 3427 } else { 3428 /* 3429 * Seems like no one is processing the SRS and 3430 * there is no backlog. We also inline process 3431 * our packet if its a single packet in non 3432 * latency optimized case (in latency optimized 3433 * case, we inline process chains of any size). 3434 */ 3435 mac_srs->srs_drain_func(mac_srs, SRS_PROC_FAST); 3436 } 3437 } 3438 mutex_exit(&mac_srs->srs_lock); 3439 } 3440 3441 /* TX SIDE ROUTINES (RUNTIME) */ 3442 3443 /* 3444 * mac_tx_srs_no_desc 3445 * 3446 * This routine is called by Tx single ring default mode 3447 * when Tx ring runs out of descs. 3448 */ 3449 mac_tx_cookie_t 3450 mac_tx_srs_no_desc(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3451 uint16_t flag, mblk_t **ret_mp) 3452 { 3453 mac_tx_cookie_t cookie = 0; 3454 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 3455 boolean_t wakeup_worker = B_TRUE; 3456 uint32_t tx_mode = srs_tx->st_mode; 3457 int cnt, sz; 3458 mblk_t *tail; 3459 3460 ASSERT(tx_mode == SRS_TX_DEFAULT || tx_mode == SRS_TX_BW); 3461 if (flag & MAC_DROP_ON_NO_DESC) { 3462 MAC_TX_SRS_DROP_MESSAGE(mac_srs, mp_chain, cookie, 3463 "Tx no desc"); 3464 } else { 3465 if (mac_srs->srs_first != NULL) 3466 wakeup_worker = B_FALSE; 3467 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 3468 if (flag & MAC_TX_NO_ENQUEUE) { 3469 /* 3470 * If TX_QUEUED is not set, queue the 3471 * packet and let mac_tx_srs_drain() 3472 * set the TX_BLOCKED bit for the 3473 * reasons explained above. Otherwise, 3474 * return the mblks. 3475 */ 3476 if (wakeup_worker) { 3477 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, 3478 mp_chain, tail, cnt, sz); 3479 } else { 3480 MAC_TX_SET_NO_ENQUEUE(mac_srs, 3481 mp_chain, ret_mp, cookie); 3482 } 3483 } else { 3484 MAC_TX_SRS_TEST_HIWAT(mac_srs, mp_chain, 3485 tail, cnt, sz, cookie); 3486 } 3487 if (wakeup_worker) 3488 cv_signal(&mac_srs->srs_async); 3489 } 3490 return (cookie); 3491 } 3492 3493 /* 3494 * mac_tx_srs_enqueue 3495 * 3496 * This routine is called when Tx SRS is operating in either serializer 3497 * or bandwidth mode. In serializer mode, a packet will get enqueued 3498 * when a thread cannot enter SRS exclusively. In bandwidth mode, 3499 * packets gets queued if allowed byte-count limit for a tick is 3500 * exceeded. The action that gets taken when MAC_DROP_ON_NO_DESC and 3501 * MAC_TX_NO_ENQUEUE is set is different than when operaing in either 3502 * the default mode or fanout mode. Here packets get dropped or 3503 * returned back to the caller only after hi-watermark worth of data 3504 * is queued. 3505 */ 3506 static mac_tx_cookie_t 3507 mac_tx_srs_enqueue(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3508 uint16_t flag, uintptr_t fanout_hint, mblk_t **ret_mp) 3509 { 3510 mac_tx_cookie_t cookie = 0; 3511 int cnt, sz; 3512 mblk_t *tail; 3513 boolean_t wakeup_worker = B_TRUE; 3514 3515 /* 3516 * Ignore fanout hint if we don't have multiple tx rings. 3517 */ 3518 if (!MAC_TX_SOFT_RINGS(mac_srs)) 3519 fanout_hint = 0; 3520 3521 if (mac_srs->srs_first != NULL) 3522 wakeup_worker = B_FALSE; 3523 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 3524 if (flag & MAC_DROP_ON_NO_DESC) { 3525 if (mac_srs->srs_count > mac_srs->srs_tx.st_hiwat) { 3526 MAC_TX_SRS_DROP_MESSAGE(mac_srs, mp_chain, cookie, 3527 "Tx SRS hiwat"); 3528 } else { 3529 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, 3530 mp_chain, tail, cnt, sz); 3531 } 3532 } else if (flag & MAC_TX_NO_ENQUEUE) { 3533 if ((mac_srs->srs_count > mac_srs->srs_tx.st_hiwat) || 3534 (mac_srs->srs_state & SRS_TX_WAKEUP_CLIENT)) { 3535 MAC_TX_SET_NO_ENQUEUE(mac_srs, mp_chain, 3536 ret_mp, cookie); 3537 } else { 3538 mp_chain->b_prev = (mblk_t *)fanout_hint; 3539 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, 3540 mp_chain, tail, cnt, sz); 3541 } 3542 } else { 3543 /* 3544 * If you are BW_ENFORCED, just enqueue the 3545 * packet. srs_worker will drain it at the 3546 * prescribed rate. Before enqueueing, save 3547 * the fanout hint. 3548 */ 3549 mp_chain->b_prev = (mblk_t *)fanout_hint; 3550 MAC_TX_SRS_TEST_HIWAT(mac_srs, mp_chain, 3551 tail, cnt, sz, cookie); 3552 } 3553 if (wakeup_worker) 3554 cv_signal(&mac_srs->srs_async); 3555 return (cookie); 3556 } 3557 3558 /* 3559 * There are seven tx modes: 3560 * 3561 * 1) Default mode (SRS_TX_DEFAULT) 3562 * 2) Serialization mode (SRS_TX_SERIALIZE) 3563 * 3) Fanout mode (SRS_TX_FANOUT) 3564 * 4) Bandwdith mode (SRS_TX_BW) 3565 * 5) Fanout and Bandwidth mode (SRS_TX_BW_FANOUT) 3566 * 6) aggr Tx mode (SRS_TX_AGGR) 3567 * 7) aggr Tx bw mode (SRS_TX_BW_AGGR) 3568 * 3569 * The tx mode in which an SRS operates is decided in mac_tx_srs_setup() 3570 * based on the number of Tx rings requested for an SRS and whether 3571 * bandwidth control is requested or not. 3572 * 3573 * The default mode (i.e., no fanout/no bandwidth) is used when the 3574 * underlying NIC does not have Tx rings or just one Tx ring. In this mode, 3575 * the SRS acts as a pass-thru. Packets will go directly to mac_tx_send(). 3576 * When the underlying Tx ring runs out of Tx descs, it starts queueing up 3577 * packets in SRS. When flow-control is relieved, the srs_worker drains 3578 * the queued packets and informs blocked clients to restart sending 3579 * packets. 3580 * 3581 * In the SRS_TX_SERIALIZE mode, all calls to mac_tx() are serialized. This 3582 * mode is used when the link has no Tx rings or only one Tx ring. 3583 * 3584 * In the SRS_TX_FANOUT mode, packets will be fanned out to multiple 3585 * Tx rings. Each Tx ring will have a soft ring associated with it. 3586 * These soft rings will be hung off the Tx SRS. Queueing if it happens 3587 * due to lack of Tx desc will be in individual soft ring (and not srs) 3588 * associated with Tx ring. 3589 * 3590 * In the TX_BW mode, tx srs will allow packets to go down to Tx ring 3591 * only if bw is available. Otherwise the packets will be queued in 3592 * SRS. If fanout to multiple Tx rings is configured, the packets will 3593 * be fanned out among the soft rings associated with the Tx rings. 3594 * 3595 * In SRS_TX_AGGR mode, mac_tx_aggr_mode() routine is called. This routine 3596 * invokes an aggr function, aggr_find_tx_ring(), to find a pseudo Tx ring 3597 * belonging to a port on which the packet has to be sent. Aggr will 3598 * always have a pseudo Tx ring associated with it even when it is an 3599 * aggregation over a single NIC that has no Tx rings. Even in such a 3600 * case, the single pseudo Tx ring will have a soft ring associated with 3601 * it and the soft ring will hang off the SRS. 3602 * 3603 * If a bandwidth is specified for an aggr, SRS_TX_BW_AGGR mode is used. 3604 * In this mode, the bandwidth is first applied on the outgoing packets 3605 * and later mac_tx_addr_mode() function is called to send the packet out 3606 * of one of the pseudo Tx rings. 3607 * 3608 * Four flags are used in srs_state for indicating flow control 3609 * conditions : SRS_TX_BLOCKED, SRS_TX_HIWAT, SRS_TX_WAKEUP_CLIENT. 3610 * SRS_TX_BLOCKED indicates out of Tx descs. SRS expects a wakeup from the 3611 * driver below. 3612 * SRS_TX_HIWAT indicates packet count enqueued in Tx SRS exceeded Tx hiwat 3613 * and flow-control pressure is applied back to clients. The clients expect 3614 * wakeup when flow-control is relieved. 3615 * SRS_TX_WAKEUP_CLIENT get set when (flag == MAC_TX_NO_ENQUEUE) and mblk 3616 * got returned back to client either due to lack of Tx descs or due to bw 3617 * control reasons. The clients expect a wakeup when condition is relieved. 3618 * 3619 * The fourth argument to mac_tx() is the flag. Normally it will be 0 but 3620 * some clients set the following values too: MAC_DROP_ON_NO_DESC, 3621 * MAC_TX_NO_ENQUEUE 3622 * Mac clients that do not want packets to be enqueued in the mac layer set 3623 * MAC_DROP_ON_NO_DESC value. The packets won't be queued in the Tx SRS or 3624 * Tx soft rings but instead get dropped when the NIC runs out of desc. The 3625 * behaviour of this flag is different when the Tx is running in serializer 3626 * or bandwidth mode. Under these (Serializer, bandwidth) modes, the packet 3627 * get dropped when Tx high watermark is reached. 3628 * There are some mac clients like vsw, aggr that want the mblks to be 3629 * returned back to clients instead of being queued in Tx SRS (or Tx soft 3630 * rings) under flow-control (i.e., out of desc or exceeding bw limits) 3631 * conditions. These clients call mac_tx() with MAC_TX_NO_ENQUEUE flag set. 3632 * In the default and Tx fanout mode, the un-transmitted mblks will be 3633 * returned back to the clients when the driver runs out of Tx descs. 3634 * SRS_TX_WAKEUP_CLIENT (or S_RING_WAKEUP_CLIENT) will be set in SRS (or 3635 * soft ring) so that the clients can be woken up when Tx desc become 3636 * available. When running in serializer or bandwidth mode mode, 3637 * SRS_TX_WAKEUP_CLIENT will be set when tx hi-watermark is reached. 3638 */ 3639 3640 mac_tx_func_t 3641 mac_tx_get_func(uint32_t mode) 3642 { 3643 return (mac_tx_mode_list[mode].mac_tx_func); 3644 } 3645 3646 /* ARGSUSED */ 3647 static mac_tx_cookie_t 3648 mac_tx_single_ring_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3649 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 3650 { 3651 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 3652 mac_tx_stats_t stats; 3653 mac_tx_cookie_t cookie = 0; 3654 3655 ASSERT(srs_tx->st_mode == SRS_TX_DEFAULT); 3656 3657 /* Regular case with a single Tx ring */ 3658 /* 3659 * SRS_TX_BLOCKED is set when underlying NIC runs 3660 * out of Tx descs and messages start getting 3661 * queued. It won't get reset until 3662 * tx_srs_drain() completely drains out the 3663 * messages. 3664 */ 3665 if ((mac_srs->srs_state & SRS_ENQUEUED) != 0) { 3666 /* Tx descs/resources not available */ 3667 mutex_enter(&mac_srs->srs_lock); 3668 if ((mac_srs->srs_state & SRS_ENQUEUED) != 0) { 3669 cookie = mac_tx_srs_no_desc(mac_srs, mp_chain, 3670 flag, ret_mp); 3671 mutex_exit(&mac_srs->srs_lock); 3672 return (cookie); 3673 } 3674 /* 3675 * While we were computing mblk count, the 3676 * flow control condition got relieved. 3677 * Continue with the transmission. 3678 */ 3679 mutex_exit(&mac_srs->srs_lock); 3680 } 3681 3682 mp_chain = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 3683 mp_chain, &stats); 3684 3685 /* 3686 * Multiple threads could be here sending packets. 3687 * Under such conditions, it is not possible to 3688 * automically set SRS_TX_BLOCKED bit to indicate 3689 * out of tx desc condition. To atomically set 3690 * this, we queue the returned packet and do 3691 * the setting of SRS_TX_BLOCKED in 3692 * mac_tx_srs_drain(). 3693 */ 3694 if (mp_chain != NULL) { 3695 mutex_enter(&mac_srs->srs_lock); 3696 cookie = mac_tx_srs_no_desc(mac_srs, mp_chain, flag, ret_mp); 3697 mutex_exit(&mac_srs->srs_lock); 3698 return (cookie); 3699 } 3700 SRS_TX_STATS_UPDATE(mac_srs, &stats); 3701 3702 return (0); 3703 } 3704 3705 /* 3706 * mac_tx_serialize_mode 3707 * 3708 * This is an experimental mode implemented as per the request of PAE. 3709 * In this mode, all callers attempting to send a packet to the NIC 3710 * will get serialized. Only one thread at any time will access the 3711 * NIC to send the packet out. 3712 */ 3713 /* ARGSUSED */ 3714 static mac_tx_cookie_t 3715 mac_tx_serializer_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3716 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 3717 { 3718 mac_tx_stats_t stats; 3719 mac_tx_cookie_t cookie = 0; 3720 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 3721 3722 /* Single ring, serialize below */ 3723 ASSERT(srs_tx->st_mode == SRS_TX_SERIALIZE); 3724 mutex_enter(&mac_srs->srs_lock); 3725 if ((mac_srs->srs_first != NULL) || 3726 (mac_srs->srs_state & SRS_PROC)) { 3727 /* 3728 * In serialization mode, queue all packets until 3729 * TX_HIWAT is set. 3730 * If drop bit is set, drop if TX_HIWAT is set. 3731 * If no_enqueue is set, still enqueue until hiwat 3732 * is set and return mblks after TX_HIWAT is set. 3733 */ 3734 cookie = mac_tx_srs_enqueue(mac_srs, mp_chain, 3735 flag, 0, ret_mp); 3736 mutex_exit(&mac_srs->srs_lock); 3737 return (cookie); 3738 } 3739 /* 3740 * No packets queued, nothing on proc and no flow 3741 * control condition. Fast-path, ok. Do inline 3742 * processing. 3743 */ 3744 mac_srs->srs_state |= SRS_PROC; 3745 mutex_exit(&mac_srs->srs_lock); 3746 3747 mp_chain = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 3748 mp_chain, &stats); 3749 3750 mutex_enter(&mac_srs->srs_lock); 3751 mac_srs->srs_state &= ~SRS_PROC; 3752 if (mp_chain != NULL) { 3753 cookie = mac_tx_srs_enqueue(mac_srs, 3754 mp_chain, flag, 0, ret_mp); 3755 } 3756 if (mac_srs->srs_first != NULL) { 3757 /* 3758 * We processed inline our packet and a new 3759 * packet/s got queued while we were 3760 * processing. Wakeup srs worker 3761 */ 3762 cv_signal(&mac_srs->srs_async); 3763 } 3764 mutex_exit(&mac_srs->srs_lock); 3765 3766 if (cookie == 0) 3767 SRS_TX_STATS_UPDATE(mac_srs, &stats); 3768 3769 return (cookie); 3770 } 3771 3772 /* 3773 * mac_tx_fanout_mode 3774 * 3775 * In this mode, the SRS will have access to multiple Tx rings to send 3776 * the packet out. The fanout hint that is passed as an argument is 3777 * used to find an appropriate ring to fanout the traffic. Each Tx 3778 * ring, in turn, will have a soft ring associated with it. If a Tx 3779 * ring runs out of Tx desc's the returned packet will be queued in 3780 * the soft ring associated with that Tx ring. The srs itself will not 3781 * queue any packets. 3782 */ 3783 3784 #define MAC_TX_SOFT_RING_PROCESS(chain) { \ 3785 index = COMPUTE_INDEX(hash, mac_srs->srs_tx_ring_count), \ 3786 softring = mac_srs->srs_tx_soft_rings[index]; \ 3787 cookie = mac_tx_soft_ring_process(softring, chain, flag, ret_mp); \ 3788 DTRACE_PROBE2(tx__fanout, uint64_t, hash, uint_t, index); \ 3789 } 3790 3791 static mac_tx_cookie_t 3792 mac_tx_fanout_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3793 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 3794 { 3795 mac_soft_ring_t *softring; 3796 uint64_t hash; 3797 uint_t index; 3798 mac_tx_cookie_t cookie = 0; 3799 3800 ASSERT(mac_srs->srs_tx.st_mode == SRS_TX_FANOUT || 3801 mac_srs->srs_tx.st_mode == SRS_TX_BW_FANOUT); 3802 if (fanout_hint != 0) { 3803 /* 3804 * The hint is specified by the caller, simply pass the 3805 * whole chain to the soft ring. 3806 */ 3807 hash = HASH_HINT(fanout_hint); 3808 MAC_TX_SOFT_RING_PROCESS(mp_chain); 3809 } else { 3810 mblk_t *last_mp, *cur_mp, *sub_chain; 3811 uint64_t last_hash = 0; 3812 uint_t media = mac_srs->srs_mcip->mci_mip->mi_info.mi_media; 3813 3814 /* 3815 * Compute the hash from the contents (headers) of the 3816 * packets of the mblk chain. Split the chains into 3817 * subchains of the same conversation. 3818 * 3819 * Since there may be more than one ring used for 3820 * sub-chains of the same call, and since the caller 3821 * does not maintain per conversation state since it 3822 * passed a zero hint, unsent subchains will be 3823 * dropped. 3824 */ 3825 3826 flag |= MAC_DROP_ON_NO_DESC; 3827 ret_mp = NULL; 3828 3829 ASSERT(ret_mp == NULL); 3830 3831 sub_chain = NULL; 3832 last_mp = NULL; 3833 3834 for (cur_mp = mp_chain; cur_mp != NULL; 3835 cur_mp = cur_mp->b_next) { 3836 hash = mac_pkt_hash(media, cur_mp, MAC_PKT_HASH_L4, 3837 B_TRUE); 3838 if (last_hash != 0 && hash != last_hash) { 3839 /* 3840 * Starting a different subchain, send current 3841 * chain out. 3842 */ 3843 ASSERT(last_mp != NULL); 3844 last_mp->b_next = NULL; 3845 MAC_TX_SOFT_RING_PROCESS(sub_chain); 3846 sub_chain = NULL; 3847 } 3848 3849 /* add packet to subchain */ 3850 if (sub_chain == NULL) 3851 sub_chain = cur_mp; 3852 last_mp = cur_mp; 3853 last_hash = hash; 3854 } 3855 3856 if (sub_chain != NULL) { 3857 /* send last subchain */ 3858 ASSERT(last_mp != NULL); 3859 last_mp->b_next = NULL; 3860 MAC_TX_SOFT_RING_PROCESS(sub_chain); 3861 } 3862 3863 cookie = 0; 3864 } 3865 3866 return (cookie); 3867 } 3868 3869 /* 3870 * mac_tx_bw_mode 3871 * 3872 * In the bandwidth mode, Tx srs will allow packets to go down to Tx ring 3873 * only if bw is available. Otherwise the packets will be queued in 3874 * SRS. If the SRS has multiple Tx rings, then packets will get fanned 3875 * out to a Tx rings. 3876 */ 3877 static mac_tx_cookie_t 3878 mac_tx_bw_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3879 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 3880 { 3881 int cnt, sz; 3882 mblk_t *tail; 3883 mac_tx_cookie_t cookie = 0; 3884 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 3885 clock_t now; 3886 3887 ASSERT(TX_BANDWIDTH_MODE(mac_srs)); 3888 ASSERT(mac_srs->srs_type & SRST_BW_CONTROL); 3889 mutex_enter(&mac_srs->srs_lock); 3890 if (mac_srs->srs_bw->mac_bw_limit == 0) { 3891 /* 3892 * zero bandwidth, no traffic is sent: drop the packets, 3893 * or return the whole chain if the caller requests all 3894 * unsent packets back. 3895 */ 3896 if (flag & MAC_TX_NO_ENQUEUE) { 3897 cookie = (mac_tx_cookie_t)mac_srs; 3898 *ret_mp = mp_chain; 3899 } else { 3900 MAC_TX_SRS_DROP_MESSAGE(mac_srs, mp_chain, cookie, 3901 "Tx no bandwidth"); 3902 } 3903 mutex_exit(&mac_srs->srs_lock); 3904 return (cookie); 3905 } else if ((mac_srs->srs_first != NULL) || 3906 (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) { 3907 cookie = mac_tx_srs_enqueue(mac_srs, mp_chain, flag, 3908 fanout_hint, ret_mp); 3909 mutex_exit(&mac_srs->srs_lock); 3910 return (cookie); 3911 } 3912 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 3913 now = ddi_get_lbolt(); 3914 if (mac_srs->srs_bw->mac_bw_curr_time != now) { 3915 mac_srs->srs_bw->mac_bw_curr_time = now; 3916 mac_srs->srs_bw->mac_bw_used = 0; 3917 } else if (mac_srs->srs_bw->mac_bw_used > 3918 mac_srs->srs_bw->mac_bw_limit) { 3919 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED; 3920 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, 3921 mp_chain, tail, cnt, sz); 3922 /* 3923 * Wakeup worker thread. Note that worker 3924 * thread has to be woken up so that it 3925 * can fire up the timer to be woken up 3926 * on the next tick. Also once 3927 * BW_ENFORCED is set, it can only be 3928 * reset by srs_worker thread. Until then 3929 * all packets will get queued up in SRS 3930 * and hence this this code path won't be 3931 * entered until BW_ENFORCED is reset. 3932 */ 3933 cv_signal(&mac_srs->srs_async); 3934 mutex_exit(&mac_srs->srs_lock); 3935 return (cookie); 3936 } 3937 3938 mac_srs->srs_bw->mac_bw_used += sz; 3939 mutex_exit(&mac_srs->srs_lock); 3940 3941 if (srs_tx->st_mode == SRS_TX_BW_FANOUT) { 3942 mac_soft_ring_t *softring; 3943 uint_t indx, hash; 3944 3945 hash = HASH_HINT(fanout_hint); 3946 indx = COMPUTE_INDEX(hash, 3947 mac_srs->srs_tx_ring_count); 3948 softring = mac_srs->srs_tx_soft_rings[indx]; 3949 return (mac_tx_soft_ring_process(softring, mp_chain, flag, 3950 ret_mp)); 3951 } else if (srs_tx->st_mode == SRS_TX_BW_AGGR) { 3952 return (mac_tx_aggr_mode(mac_srs, mp_chain, 3953 fanout_hint, flag, ret_mp)); 3954 } else { 3955 mac_tx_stats_t stats; 3956 3957 mp_chain = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 3958 mp_chain, &stats); 3959 3960 if (mp_chain != NULL) { 3961 mutex_enter(&mac_srs->srs_lock); 3962 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 3963 if (mac_srs->srs_bw->mac_bw_used > sz) 3964 mac_srs->srs_bw->mac_bw_used -= sz; 3965 else 3966 mac_srs->srs_bw->mac_bw_used = 0; 3967 cookie = mac_tx_srs_enqueue(mac_srs, mp_chain, flag, 3968 fanout_hint, ret_mp); 3969 mutex_exit(&mac_srs->srs_lock); 3970 return (cookie); 3971 } 3972 SRS_TX_STATS_UPDATE(mac_srs, &stats); 3973 3974 return (0); 3975 } 3976 } 3977 3978 /* 3979 * mac_tx_aggr_mode 3980 * 3981 * This routine invokes an aggr function, aggr_find_tx_ring(), to find 3982 * a (pseudo) Tx ring belonging to a port on which the packet has to 3983 * be sent. aggr_find_tx_ring() first finds the outgoing port based on 3984 * L2/L3/L4 policy and then uses the fanout_hint passed to it to pick 3985 * a Tx ring from the selected port. 3986 * 3987 * Note that a port can be deleted from the aggregation. In such a case, 3988 * the aggregation layer first separates the port from the rest of the 3989 * ports making sure that port (and thus any Tx rings associated with 3990 * it) won't get selected in the call to aggr_find_tx_ring() function. 3991 * Later calls are made to mac_group_rem_ring() passing pseudo Tx ring 3992 * handles one by one which in turn will quiesce the Tx SRS and remove 3993 * the soft ring associated with the pseudo Tx ring. Unlike Rx side 3994 * where a cookie is used to protect against mac_rx_ring() calls on 3995 * rings that have been removed, no such cookie is needed on the Tx 3996 * side as the pseudo Tx ring won't be available anymore to 3997 * aggr_find_tx_ring() once the port has been removed. 3998 */ 3999 static mac_tx_cookie_t 4000 mac_tx_aggr_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 4001 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 4002 { 4003 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 4004 mac_tx_ring_fn_t find_tx_ring_fn; 4005 mac_ring_handle_t ring = NULL; 4006 void *arg; 4007 mac_soft_ring_t *sringp; 4008 4009 find_tx_ring_fn = srs_tx->st_capab_aggr.mca_find_tx_ring_fn; 4010 arg = srs_tx->st_capab_aggr.mca_arg; 4011 if (find_tx_ring_fn(arg, mp_chain, fanout_hint, &ring) == NULL) 4012 return (0); 4013 sringp = srs_tx->st_soft_rings[((mac_ring_t *)ring)->mr_index]; 4014 return (mac_tx_soft_ring_process(sringp, mp_chain, flag, ret_mp)); 4015 } 4016 4017 void 4018 mac_tx_invoke_callbacks(mac_client_impl_t *mcip, mac_tx_cookie_t cookie) 4019 { 4020 mac_cb_t *mcb; 4021 mac_tx_notify_cb_t *mtnfp; 4022 4023 /* Wakeup callback registered clients */ 4024 MAC_CALLBACK_WALKER_INC(&mcip->mci_tx_notify_cb_info); 4025 for (mcb = mcip->mci_tx_notify_cb_list; mcb != NULL; 4026 mcb = mcb->mcb_nextp) { 4027 mtnfp = (mac_tx_notify_cb_t *)mcb->mcb_objp; 4028 mtnfp->mtnf_fn(mtnfp->mtnf_arg, cookie); 4029 } 4030 MAC_CALLBACK_WALKER_DCR(&mcip->mci_tx_notify_cb_info, 4031 &mcip->mci_tx_notify_cb_list); 4032 } 4033 4034 /* ARGSUSED */ 4035 void 4036 mac_tx_srs_drain(mac_soft_ring_set_t *mac_srs, uint_t proc_type) 4037 { 4038 mblk_t *head, *tail; 4039 size_t sz; 4040 uint32_t tx_mode; 4041 uint_t saved_pkt_count; 4042 mac_tx_stats_t stats; 4043 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 4044 clock_t now; 4045 4046 saved_pkt_count = 0; 4047 ASSERT(mutex_owned(&mac_srs->srs_lock)); 4048 ASSERT(!(mac_srs->srs_state & SRS_PROC)); 4049 4050 mac_srs->srs_state |= SRS_PROC; 4051 4052 tx_mode = srs_tx->st_mode; 4053 if (tx_mode == SRS_TX_DEFAULT || tx_mode == SRS_TX_SERIALIZE) { 4054 if (mac_srs->srs_first != NULL) { 4055 head = mac_srs->srs_first; 4056 tail = mac_srs->srs_last; 4057 saved_pkt_count = mac_srs->srs_count; 4058 mac_srs->srs_first = NULL; 4059 mac_srs->srs_last = NULL; 4060 mac_srs->srs_count = 0; 4061 mutex_exit(&mac_srs->srs_lock); 4062 4063 head = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 4064 head, &stats); 4065 4066 mutex_enter(&mac_srs->srs_lock); 4067 if (head != NULL) { 4068 /* Device out of tx desc, set block */ 4069 if (head->b_next == NULL) 4070 VERIFY(head == tail); 4071 tail->b_next = mac_srs->srs_first; 4072 mac_srs->srs_first = head; 4073 mac_srs->srs_count += 4074 (saved_pkt_count - stats.mts_opackets); 4075 if (mac_srs->srs_last == NULL) 4076 mac_srs->srs_last = tail; 4077 MAC_TX_SRS_BLOCK(mac_srs, head); 4078 } else { 4079 srs_tx->st_woken_up = B_FALSE; 4080 SRS_TX_STATS_UPDATE(mac_srs, &stats); 4081 } 4082 } 4083 } else if (tx_mode == SRS_TX_BW) { 4084 /* 4085 * We are here because the timer fired and we have some data 4086 * to tranmit. Also mac_tx_srs_worker should have reset 4087 * SRS_BW_ENFORCED flag 4088 */ 4089 ASSERT(!(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)); 4090 head = tail = mac_srs->srs_first; 4091 while (mac_srs->srs_first != NULL) { 4092 tail = mac_srs->srs_first; 4093 tail->b_prev = NULL; 4094 mac_srs->srs_first = tail->b_next; 4095 if (mac_srs->srs_first == NULL) 4096 mac_srs->srs_last = NULL; 4097 mac_srs->srs_count--; 4098 sz = msgdsize(tail); 4099 mac_srs->srs_size -= sz; 4100 saved_pkt_count++; 4101 MAC_TX_UPDATE_BW_INFO(mac_srs, sz); 4102 4103 if (mac_srs->srs_bw->mac_bw_used < 4104 mac_srs->srs_bw->mac_bw_limit) 4105 continue; 4106 4107 now = ddi_get_lbolt(); 4108 if (mac_srs->srs_bw->mac_bw_curr_time != now) { 4109 mac_srs->srs_bw->mac_bw_curr_time = now; 4110 mac_srs->srs_bw->mac_bw_used = sz; 4111 continue; 4112 } 4113 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED; 4114 break; 4115 } 4116 4117 ASSERT((head == NULL && tail == NULL) || 4118 (head != NULL && tail != NULL)); 4119 if (tail != NULL) { 4120 tail->b_next = NULL; 4121 mutex_exit(&mac_srs->srs_lock); 4122 4123 head = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 4124 head, &stats); 4125 4126 mutex_enter(&mac_srs->srs_lock); 4127 if (head != NULL) { 4128 uint_t size_sent; 4129 4130 /* Device out of tx desc, set block */ 4131 if (head->b_next == NULL) 4132 VERIFY(head == tail); 4133 tail->b_next = mac_srs->srs_first; 4134 mac_srs->srs_first = head; 4135 mac_srs->srs_count += 4136 (saved_pkt_count - stats.mts_opackets); 4137 if (mac_srs->srs_last == NULL) 4138 mac_srs->srs_last = tail; 4139 size_sent = sz - stats.mts_obytes; 4140 mac_srs->srs_size += size_sent; 4141 mac_srs->srs_bw->mac_bw_sz += size_sent; 4142 if (mac_srs->srs_bw->mac_bw_used > size_sent) { 4143 mac_srs->srs_bw->mac_bw_used -= 4144 size_sent; 4145 } else { 4146 mac_srs->srs_bw->mac_bw_used = 0; 4147 } 4148 MAC_TX_SRS_BLOCK(mac_srs, head); 4149 } else { 4150 srs_tx->st_woken_up = B_FALSE; 4151 SRS_TX_STATS_UPDATE(mac_srs, &stats); 4152 } 4153 } 4154 } else if (tx_mode == SRS_TX_BW_FANOUT || tx_mode == SRS_TX_BW_AGGR) { 4155 mblk_t *prev; 4156 uint64_t hint; 4157 4158 /* 4159 * We are here because the timer fired and we 4160 * have some quota to tranmit. 4161 */ 4162 prev = NULL; 4163 head = tail = mac_srs->srs_first; 4164 while (mac_srs->srs_first != NULL) { 4165 tail = mac_srs->srs_first; 4166 mac_srs->srs_first = tail->b_next; 4167 if (mac_srs->srs_first == NULL) 4168 mac_srs->srs_last = NULL; 4169 mac_srs->srs_count--; 4170 sz = msgdsize(tail); 4171 mac_srs->srs_size -= sz; 4172 mac_srs->srs_bw->mac_bw_used += sz; 4173 if (prev == NULL) 4174 hint = (ulong_t)tail->b_prev; 4175 if (hint != (ulong_t)tail->b_prev) { 4176 prev->b_next = NULL; 4177 mutex_exit(&mac_srs->srs_lock); 4178 TX_SRS_TO_SOFT_RING(mac_srs, head, hint); 4179 head = tail; 4180 hint = (ulong_t)tail->b_prev; 4181 mutex_enter(&mac_srs->srs_lock); 4182 } 4183 4184 prev = tail; 4185 tail->b_prev = NULL; 4186 if (mac_srs->srs_bw->mac_bw_used < 4187 mac_srs->srs_bw->mac_bw_limit) 4188 continue; 4189 4190 now = ddi_get_lbolt(); 4191 if (mac_srs->srs_bw->mac_bw_curr_time != now) { 4192 mac_srs->srs_bw->mac_bw_curr_time = now; 4193 mac_srs->srs_bw->mac_bw_used = 0; 4194 continue; 4195 } 4196 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED; 4197 break; 4198 } 4199 ASSERT((head == NULL && tail == NULL) || 4200 (head != NULL && tail != NULL)); 4201 if (tail != NULL) { 4202 tail->b_next = NULL; 4203 mutex_exit(&mac_srs->srs_lock); 4204 TX_SRS_TO_SOFT_RING(mac_srs, head, hint); 4205 mutex_enter(&mac_srs->srs_lock); 4206 } 4207 } 4208 /* 4209 * SRS_TX_FANOUT case not considered here because packets 4210 * won't be queued in the SRS for this case. Packets will 4211 * be sent directly to soft rings underneath and if there 4212 * is any queueing at all, it would be in Tx side soft 4213 * rings. 4214 */ 4215 4216 /* 4217 * When srs_count becomes 0, reset SRS_TX_HIWAT and 4218 * SRS_TX_WAKEUP_CLIENT and wakeup registered clients. 4219 */ 4220 if (mac_srs->srs_count == 0 && (mac_srs->srs_state & 4221 (SRS_TX_HIWAT | SRS_TX_WAKEUP_CLIENT | SRS_ENQUEUED))) { 4222 mac_client_impl_t *mcip = mac_srs->srs_mcip; 4223 boolean_t wakeup_required = B_FALSE; 4224 4225 if (mac_srs->srs_state & 4226 (SRS_TX_HIWAT|SRS_TX_WAKEUP_CLIENT)) { 4227 wakeup_required = B_TRUE; 4228 } 4229 mac_srs->srs_state &= ~(SRS_TX_HIWAT | 4230 SRS_TX_WAKEUP_CLIENT | SRS_ENQUEUED); 4231 mutex_exit(&mac_srs->srs_lock); 4232 if (wakeup_required) { 4233 mac_tx_invoke_callbacks(mcip, (mac_tx_cookie_t)mac_srs); 4234 /* 4235 * If the client is not the primary MAC client, then we 4236 * need to send the notification to the clients upper 4237 * MAC, i.e. mci_upper_mip. 4238 */ 4239 mac_tx_notify(mcip->mci_upper_mip != NULL ? 4240 mcip->mci_upper_mip : mcip->mci_mip); 4241 } 4242 mutex_enter(&mac_srs->srs_lock); 4243 } 4244 mac_srs->srs_state &= ~SRS_PROC; 4245 } 4246 4247 /* 4248 * Given a packet, get the flow_entry that identifies the flow 4249 * to which that packet belongs. The flow_entry will contain 4250 * the transmit function to be used to send the packet. If the 4251 * function returns NULL, the packet should be sent using the 4252 * underlying NIC. 4253 */ 4254 static flow_entry_t * 4255 mac_tx_classify(mac_impl_t *mip, mblk_t *mp) 4256 { 4257 flow_entry_t *flent = NULL; 4258 mac_client_impl_t *mcip; 4259 int err; 4260 4261 /* 4262 * Do classification on the packet. 4263 */ 4264 err = mac_flow_lookup(mip->mi_flow_tab, mp, FLOW_OUTBOUND, &flent); 4265 if (err != 0) 4266 return (NULL); 4267 4268 /* 4269 * This flent might just be an additional one on the MAC client, 4270 * i.e. for classification purposes (different fdesc), however 4271 * the resources, SRS et. al., are in the mci_flent, so if 4272 * this isn't the mci_flent, we need to get it. 4273 */ 4274 if ((mcip = flent->fe_mcip) != NULL && mcip->mci_flent != flent) { 4275 FLOW_REFRELE(flent); 4276 flent = mcip->mci_flent; 4277 FLOW_TRY_REFHOLD(flent, err); 4278 if (err != 0) 4279 return (NULL); 4280 } 4281 4282 return (flent); 4283 } 4284 4285 /* 4286 * This macro is only meant to be used by mac_tx_send(). 4287 */ 4288 #define CHECK_VID_AND_ADD_TAG(mp) { \ 4289 if (vid_check) { \ 4290 int err = 0; \ 4291 \ 4292 MAC_VID_CHECK(src_mcip, (mp), err); \ 4293 if (err != 0) { \ 4294 freemsg((mp)); \ 4295 (mp) = next; \ 4296 oerrors++; \ 4297 continue; \ 4298 } \ 4299 } \ 4300 if (add_tag) { \ 4301 (mp) = mac_add_vlan_tag((mp), 0, vid); \ 4302 if ((mp) == NULL) { \ 4303 (mp) = next; \ 4304 oerrors++; \ 4305 continue; \ 4306 } \ 4307 } \ 4308 } 4309 4310 mblk_t * 4311 mac_tx_send(mac_client_handle_t mch, mac_ring_handle_t ring, mblk_t *mp_chain, 4312 mac_tx_stats_t *stats) 4313 { 4314 mac_client_impl_t *src_mcip = (mac_client_impl_t *)mch; 4315 mac_impl_t *mip = src_mcip->mci_mip; 4316 uint_t obytes = 0, opackets = 0, oerrors = 0; 4317 mblk_t *mp = NULL, *next; 4318 boolean_t vid_check, add_tag; 4319 uint16_t vid = 0; 4320 4321 if (mip->mi_nclients > 1) { 4322 vid_check = MAC_VID_CHECK_NEEDED(src_mcip); 4323 add_tag = MAC_TAG_NEEDED(src_mcip); 4324 if (add_tag) 4325 vid = mac_client_vid(mch); 4326 } else { 4327 ASSERT(mip->mi_nclients == 1); 4328 vid_check = add_tag = B_FALSE; 4329 } 4330 4331 /* 4332 * Fastpath: if there's only one client, we simply send 4333 * the packet down to the underlying NIC. 4334 */ 4335 if (mip->mi_nactiveclients == 1) { 4336 DTRACE_PROBE2(fastpath, 4337 mac_client_impl_t *, src_mcip, mblk_t *, mp_chain); 4338 4339 mp = mp_chain; 4340 while (mp != NULL) { 4341 next = mp->b_next; 4342 mp->b_next = NULL; 4343 opackets++; 4344 obytes += (mp->b_cont == NULL ? MBLKL(mp) : 4345 msgdsize(mp)); 4346 4347 CHECK_VID_AND_ADD_TAG(mp); 4348 mp = mac_provider_tx(mip, ring, mp, src_mcip); 4349 4350 /* 4351 * If the driver is out of descriptors and does a 4352 * partial send it will return a chain of unsent 4353 * mblks. Adjust the accounting stats. 4354 */ 4355 if (mp != NULL) { 4356 opackets--; 4357 obytes -= msgdsize(mp); 4358 mp->b_next = next; 4359 break; 4360 } 4361 mp = next; 4362 } 4363 goto done; 4364 } 4365 4366 /* 4367 * No fastpath, we either have more than one MAC client 4368 * defined on top of the same MAC, or one or more MAC 4369 * client promiscuous callbacks. 4370 */ 4371 DTRACE_PROBE3(slowpath, mac_client_impl_t *, 4372 src_mcip, int, mip->mi_nclients, mblk_t *, mp_chain); 4373 4374 mp = mp_chain; 4375 while (mp != NULL) { 4376 flow_entry_t *dst_flow_ent; 4377 void *flow_cookie; 4378 size_t pkt_size; 4379 4380 next = mp->b_next; 4381 mp->b_next = NULL; 4382 opackets++; 4383 pkt_size = (mp->b_cont == NULL ? MBLKL(mp) : msgdsize(mp)); 4384 obytes += pkt_size; 4385 CHECK_VID_AND_ADD_TAG(mp); 4386 4387 /* 4388 * Find the destination. 4389 */ 4390 dst_flow_ent = mac_tx_classify(mip, mp); 4391 4392 if (dst_flow_ent != NULL) { 4393 /* 4394 * Got a matching flow. It's either another 4395 * MAC client, or a broadcast/multicast flow. 4396 */ 4397 flow_cookie = mac_flow_get_client_cookie(dst_flow_ent); 4398 4399 if (flow_cookie != NULL) { 4400 /* 4401 * The vnic_bcast_send function expects 4402 * to receive the sender MAC client 4403 * as value for arg2. 4404 */ 4405 mac_bcast_send(flow_cookie, src_mcip, mp, 4406 B_TRUE); 4407 } else { 4408 /* 4409 * loopback the packet to a local MAC 4410 * client. We force a context switch 4411 * if both source and destination MAC 4412 * clients are used by IP, i.e. 4413 * bypass is set. 4414 */ 4415 boolean_t do_switch; 4416 4417 mac_client_impl_t *dst_mcip = 4418 dst_flow_ent->fe_mcip; 4419 4420 /* 4421 * Check if there are promiscuous mode 4422 * callbacks defined. This check is 4423 * done here in the 'else' case and 4424 * not in other cases because this 4425 * path is for local loopback 4426 * communication which does not go 4427 * through MAC_TX(). For paths that go 4428 * through MAC_TX(), the promisc_list 4429 * check is done inside the MAC_TX() 4430 * macro. 4431 */ 4432 if (mip->mi_promisc_list != NULL) { 4433 mac_promisc_dispatch(mip, mp, src_mcip, 4434 B_TRUE); 4435 } 4436 4437 do_switch = ((src_mcip->mci_state_flags & 4438 dst_mcip->mci_state_flags & 4439 MCIS_CLIENT_POLL_CAPABLE) != 0); 4440 4441 mac_hw_emul(&mp, NULL, NULL, MAC_ALL_EMULS); 4442 if (mp != NULL) { 4443 (dst_flow_ent->fe_cb_fn)( 4444 dst_flow_ent->fe_cb_arg1, 4445 dst_flow_ent->fe_cb_arg2, 4446 mp, do_switch); 4447 } 4448 4449 } 4450 FLOW_REFRELE(dst_flow_ent); 4451 } else { 4452 /* 4453 * Unknown destination, send via the underlying 4454 * NIC. 4455 */ 4456 mp = mac_provider_tx(mip, ring, mp, src_mcip); 4457 if (mp != NULL) { 4458 /* 4459 * Adjust for the last packet that 4460 * could not be transmitted 4461 */ 4462 opackets--; 4463 obytes -= pkt_size; 4464 mp->b_next = next; 4465 break; 4466 } 4467 } 4468 mp = next; 4469 } 4470 4471 done: 4472 stats->mts_obytes = obytes; 4473 stats->mts_opackets = opackets; 4474 stats->mts_oerrors = oerrors; 4475 return (mp); 4476 } 4477 4478 /* 4479 * mac_tx_srs_ring_present 4480 * 4481 * Returns whether the specified ring is part of the specified SRS. 4482 */ 4483 boolean_t 4484 mac_tx_srs_ring_present(mac_soft_ring_set_t *srs, mac_ring_t *tx_ring) 4485 { 4486 int i; 4487 mac_soft_ring_t *soft_ring; 4488 4489 if (srs->srs_tx.st_arg2 == tx_ring) 4490 return (B_TRUE); 4491 4492 for (i = 0; i < srs->srs_tx_ring_count; i++) { 4493 soft_ring = srs->srs_tx_soft_rings[i]; 4494 if (soft_ring->s_ring_tx_arg2 == tx_ring) 4495 return (B_TRUE); 4496 } 4497 4498 return (B_FALSE); 4499 } 4500 4501 /* 4502 * mac_tx_srs_get_soft_ring 4503 * 4504 * Returns the TX soft ring associated with the given ring, if present. 4505 */ 4506 mac_soft_ring_t * 4507 mac_tx_srs_get_soft_ring(mac_soft_ring_set_t *srs, mac_ring_t *tx_ring) 4508 { 4509 int i; 4510 mac_soft_ring_t *soft_ring; 4511 4512 if (srs->srs_tx.st_arg2 == tx_ring) 4513 return (NULL); 4514 4515 for (i = 0; i < srs->srs_tx_ring_count; i++) { 4516 soft_ring = srs->srs_tx_soft_rings[i]; 4517 if (soft_ring->s_ring_tx_arg2 == tx_ring) 4518 return (soft_ring); 4519 } 4520 4521 return (NULL); 4522 } 4523 4524 /* 4525 * mac_tx_srs_wakeup 4526 * 4527 * Called when Tx desc become available. Wakeup the appropriate worker 4528 * thread after resetting the SRS_TX_BLOCKED/S_RING_BLOCK bit in the 4529 * state field. 4530 */ 4531 void 4532 mac_tx_srs_wakeup(mac_soft_ring_set_t *mac_srs, mac_ring_handle_t ring) 4533 { 4534 int i; 4535 mac_soft_ring_t *sringp; 4536 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 4537 4538 mutex_enter(&mac_srs->srs_lock); 4539 /* 4540 * srs_tx_ring_count == 0 is the single ring mode case. In 4541 * this mode, there will not be Tx soft rings associated 4542 * with the SRS. 4543 */ 4544 if (!MAC_TX_SOFT_RINGS(mac_srs)) { 4545 if (srs_tx->st_arg2 == ring && 4546 mac_srs->srs_state & SRS_TX_BLOCKED) { 4547 mac_srs->srs_state &= ~SRS_TX_BLOCKED; 4548 srs_tx->st_stat.mts_unblockcnt++; 4549 cv_signal(&mac_srs->srs_async); 4550 } 4551 /* 4552 * A wakeup can come before tx_srs_drain() could 4553 * grab srs lock and set SRS_TX_BLOCKED. So 4554 * always set woken_up flag when we come here. 4555 */ 4556 srs_tx->st_woken_up = B_TRUE; 4557 mutex_exit(&mac_srs->srs_lock); 4558 return; 4559 } 4560 4561 /* 4562 * If you are here, it is for FANOUT, BW_FANOUT, 4563 * AGGR_MODE or AGGR_BW_MODE case 4564 */ 4565 for (i = 0; i < mac_srs->srs_tx_ring_count; i++) { 4566 sringp = mac_srs->srs_tx_soft_rings[i]; 4567 mutex_enter(&sringp->s_ring_lock); 4568 if (sringp->s_ring_tx_arg2 == ring) { 4569 if (sringp->s_ring_state & S_RING_BLOCK) { 4570 sringp->s_ring_state &= ~S_RING_BLOCK; 4571 sringp->s_st_stat.mts_unblockcnt++; 4572 cv_signal(&sringp->s_ring_async); 4573 } 4574 sringp->s_ring_tx_woken_up = B_TRUE; 4575 } 4576 mutex_exit(&sringp->s_ring_lock); 4577 } 4578 mutex_exit(&mac_srs->srs_lock); 4579 } 4580 4581 /* 4582 * Once the driver is done draining, send a MAC_NOTE_TX notification to unleash 4583 * the blocked clients again. 4584 */ 4585 void 4586 mac_tx_notify(mac_impl_t *mip) 4587 { 4588 i_mac_notify(mip, MAC_NOTE_TX); 4589 } 4590 4591 /* 4592 * RX SOFTRING RELATED FUNCTIONS 4593 * 4594 * These functions really belong in mac_soft_ring.c and here for 4595 * a short period. 4596 */ 4597 4598 #define SOFT_RING_ENQUEUE_CHAIN(ringp, mp, tail, cnt, sz) { \ 4599 /* \ 4600 * Enqueue our mblk chain. \ 4601 */ \ 4602 ASSERT(MUTEX_HELD(&(ringp)->s_ring_lock)); \ 4603 \ 4604 if ((ringp)->s_ring_last != NULL) \ 4605 (ringp)->s_ring_last->b_next = (mp); \ 4606 else \ 4607 (ringp)->s_ring_first = (mp); \ 4608 (ringp)->s_ring_last = (tail); \ 4609 (ringp)->s_ring_count += (cnt); \ 4610 ASSERT((ringp)->s_ring_count > 0); \ 4611 if ((ringp)->s_ring_type & ST_RING_BW_CTL) { \ 4612 (ringp)->s_ring_size += sz; \ 4613 } \ 4614 } 4615 4616 /* 4617 * Default entry point to deliver a packet chain to a MAC client. 4618 * If the MAC client has flows, do the classification with these 4619 * flows as well. 4620 */ 4621 /* ARGSUSED */ 4622 void 4623 mac_rx_deliver(void *arg1, mac_resource_handle_t mrh, mblk_t *mp_chain, 4624 mac_header_info_t *arg3) 4625 { 4626 mac_client_impl_t *mcip = arg1; 4627 4628 if (mcip->mci_nvids == 1 && 4629 !(mcip->mci_state_flags & MCIS_STRIP_DISABLE)) { 4630 /* 4631 * If the client has exactly one VID associated with it 4632 * and striping of VLAN header is not disabled, 4633 * remove the VLAN tag from the packet before 4634 * passing it on to the client's receive callback. 4635 * Note that this needs to be done after we dispatch 4636 * the packet to the promiscuous listeners of the 4637 * client, since they expect to see the whole 4638 * frame including the VLAN headers. 4639 * 4640 * The MCIS_STRIP_DISABLE is only issued when sun4v 4641 * vsw is in play. 4642 */ 4643 mp_chain = mac_strip_vlan_tag_chain(mp_chain); 4644 } 4645 4646 mcip->mci_rx_fn(mcip->mci_rx_arg, mrh, mp_chain, B_FALSE); 4647 } 4648 4649 /* 4650 * Process a chain for a given soft ring. If the number of packets 4651 * queued in the SRS and its associated soft rings (including this 4652 * one) is very small (tracked by srs_poll_pkt_cnt) then allow the 4653 * entering thread (interrupt or poll thread) to process the chain 4654 * inline. This is meant to reduce latency under low load. 4655 * 4656 * The proc and arg for each mblk is already stored in the mblk in 4657 * appropriate places. 4658 */ 4659 /* ARGSUSED */ 4660 void 4661 mac_rx_soft_ring_process(mac_client_impl_t *mcip, mac_soft_ring_t *ringp, 4662 mblk_t *mp_chain, mblk_t *tail, int cnt, size_t sz) 4663 { 4664 mac_direct_rx_t proc; 4665 void *arg1; 4666 mac_resource_handle_t arg2; 4667 mac_soft_ring_set_t *mac_srs = ringp->s_ring_set; 4668 4669 ASSERT(ringp != NULL); 4670 ASSERT(mp_chain != NULL); 4671 ASSERT(tail != NULL); 4672 ASSERT(MUTEX_NOT_HELD(&ringp->s_ring_lock)); 4673 4674 mutex_enter(&ringp->s_ring_lock); 4675 ringp->s_ring_total_inpkt += cnt; 4676 ringp->s_ring_total_rbytes += sz; 4677 if ((mac_srs->srs_rx.sr_poll_pkt_cnt <= 1) && 4678 !(ringp->s_ring_type & ST_RING_WORKER_ONLY)) { 4679 /* If on processor or blanking on, then enqueue and return */ 4680 if (ringp->s_ring_state & S_RING_BLANK || 4681 ringp->s_ring_state & S_RING_PROC) { 4682 SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz); 4683 mutex_exit(&ringp->s_ring_lock); 4684 return; 4685 } 4686 proc = ringp->s_ring_rx_func; 4687 arg1 = ringp->s_ring_rx_arg1; 4688 arg2 = ringp->s_ring_rx_arg2; 4689 /* 4690 * See if anything is already queued. If we are the 4691 * first packet, do inline processing else queue the 4692 * packet and do the drain. 4693 */ 4694 if (ringp->s_ring_first == NULL) { 4695 /* 4696 * Fast-path, ok to process and nothing queued. 4697 */ 4698 ringp->s_ring_run = curthread; 4699 ringp->s_ring_state |= (S_RING_PROC); 4700 4701 mutex_exit(&ringp->s_ring_lock); 4702 4703 /* 4704 * We are the chain of 1 packet so 4705 * go through this fast path. 4706 */ 4707 ASSERT(mp_chain->b_next == NULL); 4708 4709 (*proc)(arg1, arg2, mp_chain, NULL); 4710 4711 ASSERT(MUTEX_NOT_HELD(&ringp->s_ring_lock)); 4712 /* 4713 * If we have an SRS performing bandwidth 4714 * control then we need to decrement the size 4715 * and count so the SRS has an accurate count 4716 * of the data queued between the SRS and its 4717 * soft rings. We decrement the counters only 4718 * when the packet is processed by both the 4719 * SRS and the soft ring. 4720 */ 4721 mutex_enter(&mac_srs->srs_lock); 4722 MAC_UPDATE_SRS_COUNT_LOCKED(mac_srs, cnt); 4723 MAC_UPDATE_SRS_SIZE_LOCKED(mac_srs, sz); 4724 mutex_exit(&mac_srs->srs_lock); 4725 4726 mutex_enter(&ringp->s_ring_lock); 4727 ringp->s_ring_run = NULL; 4728 ringp->s_ring_state &= ~S_RING_PROC; 4729 if (ringp->s_ring_state & S_RING_CLIENT_WAIT) 4730 cv_signal(&ringp->s_ring_client_cv); 4731 4732 if ((ringp->s_ring_first == NULL) || 4733 (ringp->s_ring_state & S_RING_BLANK)) { 4734 /* 4735 * We processed a single packet inline 4736 * and nothing new has arrived or our 4737 * receiver doesn't want to receive 4738 * any packets. We are done. 4739 */ 4740 mutex_exit(&ringp->s_ring_lock); 4741 return; 4742 } 4743 } else { 4744 SOFT_RING_ENQUEUE_CHAIN(ringp, 4745 mp_chain, tail, cnt, sz); 4746 } 4747 4748 /* 4749 * We are here because either we couldn't do inline 4750 * processing (because something was already 4751 * queued), or we had a chain of more than one 4752 * packet, or something else arrived after we were 4753 * done with inline processing. 4754 */ 4755 ASSERT(MUTEX_HELD(&ringp->s_ring_lock)); 4756 ASSERT(ringp->s_ring_first != NULL); 4757 4758 ringp->s_ring_drain_func(ringp); 4759 mutex_exit(&ringp->s_ring_lock); 4760 return; 4761 } else { 4762 /* ST_RING_WORKER_ONLY case */ 4763 SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz); 4764 mac_soft_ring_worker_wakeup(ringp); 4765 mutex_exit(&ringp->s_ring_lock); 4766 } 4767 } 4768 4769 /* 4770 * TX SOFTRING RELATED FUNCTIONS 4771 * 4772 * These functions really belong in mac_soft_ring.c and here for 4773 * a short period. 4774 */ 4775 4776 #define TX_SOFT_RING_ENQUEUE_CHAIN(ringp, mp, tail, cnt, sz) { \ 4777 ASSERT(MUTEX_HELD(&ringp->s_ring_lock)); \ 4778 ringp->s_ring_state |= S_RING_ENQUEUED; \ 4779 SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz); \ 4780 } 4781 4782 /* 4783 * mac_tx_sring_queued 4784 * 4785 * When we are out of transmit descriptors and we already have a 4786 * queue that exceeds hiwat (or the client called us with 4787 * MAC_TX_NO_ENQUEUE or MAC_DROP_ON_NO_DESC flag), return the 4788 * soft ring pointer as the opaque cookie for the client enable 4789 * flow control. 4790 */ 4791 static mac_tx_cookie_t 4792 mac_tx_sring_enqueue(mac_soft_ring_t *ringp, mblk_t *mp_chain, uint16_t flag, 4793 mblk_t **ret_mp) 4794 { 4795 int cnt; 4796 size_t sz; 4797 mblk_t *tail; 4798 mac_soft_ring_set_t *mac_srs = ringp->s_ring_set; 4799 mac_tx_cookie_t cookie = 0; 4800 boolean_t wakeup_worker = B_TRUE; 4801 4802 ASSERT(MUTEX_HELD(&ringp->s_ring_lock)); 4803 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 4804 if (flag & MAC_DROP_ON_NO_DESC) { 4805 mac_drop_chain(mp_chain, "Tx softring no desc"); 4806 /* increment freed stats */ 4807 ringp->s_ring_drops += cnt; 4808 cookie = (mac_tx_cookie_t)ringp; 4809 } else { 4810 if (ringp->s_ring_first != NULL) 4811 wakeup_worker = B_FALSE; 4812 4813 if (flag & MAC_TX_NO_ENQUEUE) { 4814 /* 4815 * If QUEUED is not set, queue the packet 4816 * and let mac_tx_soft_ring_drain() set 4817 * the TX_BLOCKED bit for the reasons 4818 * explained above. Otherwise, return the 4819 * mblks. 4820 */ 4821 if (wakeup_worker) { 4822 TX_SOFT_RING_ENQUEUE_CHAIN(ringp, 4823 mp_chain, tail, cnt, sz); 4824 } else { 4825 ringp->s_ring_state |= S_RING_WAKEUP_CLIENT; 4826 cookie = (mac_tx_cookie_t)ringp; 4827 *ret_mp = mp_chain; 4828 } 4829 } else { 4830 boolean_t enqueue = B_TRUE; 4831 4832 if (ringp->s_ring_count > ringp->s_ring_tx_hiwat) { 4833 /* 4834 * flow-controlled. Store ringp in cookie 4835 * so that it can be returned as 4836 * mac_tx_cookie_t to client 4837 */ 4838 ringp->s_ring_state |= S_RING_TX_HIWAT; 4839 cookie = (mac_tx_cookie_t)ringp; 4840 ringp->s_ring_hiwat_cnt++; 4841 if (ringp->s_ring_count > 4842 ringp->s_ring_tx_max_q_cnt) { 4843 /* increment freed stats */ 4844 ringp->s_ring_drops += cnt; 4845 /* 4846 * b_prev may be set to the fanout hint 4847 * hence can't use freemsg directly 4848 */ 4849 mac_drop_chain(mp_chain, 4850 "Tx softring max queue"); 4851 DTRACE_PROBE1(tx_queued_hiwat, 4852 mac_soft_ring_t *, ringp); 4853 enqueue = B_FALSE; 4854 } 4855 } 4856 if (enqueue) { 4857 TX_SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, 4858 tail, cnt, sz); 4859 } 4860 } 4861 if (wakeup_worker) 4862 cv_signal(&ringp->s_ring_async); 4863 } 4864 return (cookie); 4865 } 4866 4867 4868 /* 4869 * mac_tx_soft_ring_process 4870 * 4871 * This routine is called when fanning out outgoing traffic among 4872 * multipe Tx rings. 4873 * Note that a soft ring is associated with a h/w Tx ring. 4874 */ 4875 mac_tx_cookie_t 4876 mac_tx_soft_ring_process(mac_soft_ring_t *ringp, mblk_t *mp_chain, 4877 uint16_t flag, mblk_t **ret_mp) 4878 { 4879 mac_soft_ring_set_t *mac_srs = ringp->s_ring_set; 4880 int cnt; 4881 size_t sz; 4882 mblk_t *tail; 4883 mac_tx_cookie_t cookie = 0; 4884 4885 ASSERT(ringp != NULL); 4886 ASSERT(mp_chain != NULL); 4887 ASSERT(MUTEX_NOT_HELD(&ringp->s_ring_lock)); 4888 /* 4889 * The following modes can come here: SRS_TX_BW_FANOUT, 4890 * SRS_TX_FANOUT, SRS_TX_AGGR, SRS_TX_BW_AGGR. 4891 */ 4892 ASSERT(MAC_TX_SOFT_RINGS(mac_srs)); 4893 ASSERT(mac_srs->srs_tx.st_mode == SRS_TX_FANOUT || 4894 mac_srs->srs_tx.st_mode == SRS_TX_BW_FANOUT || 4895 mac_srs->srs_tx.st_mode == SRS_TX_AGGR || 4896 mac_srs->srs_tx.st_mode == SRS_TX_BW_AGGR); 4897 4898 if (ringp->s_ring_type & ST_RING_WORKER_ONLY) { 4899 /* Serialization mode */ 4900 4901 mutex_enter(&ringp->s_ring_lock); 4902 if (ringp->s_ring_count > ringp->s_ring_tx_hiwat) { 4903 cookie = mac_tx_sring_enqueue(ringp, mp_chain, 4904 flag, ret_mp); 4905 mutex_exit(&ringp->s_ring_lock); 4906 return (cookie); 4907 } 4908 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 4909 TX_SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz); 4910 if (ringp->s_ring_state & (S_RING_BLOCK | S_RING_PROC)) { 4911 /* 4912 * If ring is blocked due to lack of Tx 4913 * descs, just return. Worker thread 4914 * will get scheduled when Tx desc's 4915 * become available. 4916 */ 4917 mutex_exit(&ringp->s_ring_lock); 4918 return (cookie); 4919 } 4920 mac_soft_ring_worker_wakeup(ringp); 4921 mutex_exit(&ringp->s_ring_lock); 4922 return (cookie); 4923 } else { 4924 /* Default fanout mode */ 4925 /* 4926 * S_RING_BLOCKED is set when underlying NIC runs 4927 * out of Tx descs and messages start getting 4928 * queued. It won't get reset until 4929 * tx_srs_drain() completely drains out the 4930 * messages. 4931 */ 4932 mac_tx_stats_t stats; 4933 4934 if (ringp->s_ring_state & S_RING_ENQUEUED) { 4935 /* Tx descs/resources not available */ 4936 mutex_enter(&ringp->s_ring_lock); 4937 if (ringp->s_ring_state & S_RING_ENQUEUED) { 4938 cookie = mac_tx_sring_enqueue(ringp, mp_chain, 4939 flag, ret_mp); 4940 mutex_exit(&ringp->s_ring_lock); 4941 return (cookie); 4942 } 4943 /* 4944 * While we were computing mblk count, the 4945 * flow control condition got relieved. 4946 * Continue with the transmission. 4947 */ 4948 mutex_exit(&ringp->s_ring_lock); 4949 } 4950 4951 mp_chain = mac_tx_send(ringp->s_ring_tx_arg1, 4952 ringp->s_ring_tx_arg2, mp_chain, &stats); 4953 4954 /* 4955 * Multiple threads could be here sending packets. 4956 * Under such conditions, it is not possible to 4957 * automically set S_RING_BLOCKED bit to indicate 4958 * out of tx desc condition. To atomically set 4959 * this, we queue the returned packet and do 4960 * the setting of S_RING_BLOCKED in 4961 * mac_tx_soft_ring_drain(). 4962 */ 4963 if (mp_chain != NULL) { 4964 mutex_enter(&ringp->s_ring_lock); 4965 cookie = 4966 mac_tx_sring_enqueue(ringp, mp_chain, flag, ret_mp); 4967 mutex_exit(&ringp->s_ring_lock); 4968 return (cookie); 4969 } 4970 SRS_TX_STATS_UPDATE(mac_srs, &stats); 4971 SOFTRING_TX_STATS_UPDATE(ringp, &stats); 4972 4973 return (0); 4974 } 4975 } 4976