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