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(1M), 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(1M). 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(1M), 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(1M) or bandwidth limits are set on a device with 234 * dladm(1M). 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(1M) 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 * MAC_RX_SRS_TOODEEP 1365 * 1366 * Macro called as part of receive-side processing to determine if handling 1367 * can occur in situ (in the interrupt thread) or if it should be left to a 1368 * worker thread. Note that the constant used to make this determination is 1369 * not entirely made-up, and is a result of some emprical validation. That 1370 * said, the constant is left as a static variable to allow it to be 1371 * dynamically tuned in the field if and as needed. 1372 */ 1373 static uintptr_t mac_rx_srs_stack_needed = 10240; 1374 static uint_t mac_rx_srs_stack_toodeep; 1375 1376 #ifndef STACK_GROWTH_DOWN 1377 #error Downward stack growth assumed. 1378 #endif 1379 1380 #define MAC_RX_SRS_TOODEEP() (STACK_BIAS + (uintptr_t)getfp() - \ 1381 (uintptr_t)curthread->t_stkbase < mac_rx_srs_stack_needed && \ 1382 ++mac_rx_srs_stack_toodeep) 1383 1384 1385 /* 1386 * Drop the rx packet and advance to the next one in the chain. 1387 */ 1388 static void 1389 mac_rx_drop_pkt(mac_soft_ring_set_t *srs, mblk_t *mp) 1390 { 1391 mac_srs_rx_t *srs_rx = &srs->srs_rx; 1392 1393 ASSERT(mp->b_next == NULL); 1394 mutex_enter(&srs->srs_lock); 1395 MAC_UPDATE_SRS_COUNT_LOCKED(srs, 1); 1396 MAC_UPDATE_SRS_SIZE_LOCKED(srs, msgdsize(mp)); 1397 mutex_exit(&srs->srs_lock); 1398 1399 srs_rx->sr_stat.mrs_sdrops++; 1400 freemsg(mp); 1401 } 1402 1403 /* DATAPATH RUNTIME ROUTINES */ 1404 1405 /* 1406 * mac_srs_fire 1407 * 1408 * Timer callback routine for waking up the SRS worker thread. 1409 */ 1410 static void 1411 mac_srs_fire(void *arg) 1412 { 1413 mac_soft_ring_set_t *mac_srs = (mac_soft_ring_set_t *)arg; 1414 1415 mutex_enter(&mac_srs->srs_lock); 1416 if (mac_srs->srs_tid == NULL) { 1417 mutex_exit(&mac_srs->srs_lock); 1418 return; 1419 } 1420 1421 mac_srs->srs_tid = NULL; 1422 if (!(mac_srs->srs_state & SRS_PROC)) 1423 cv_signal(&mac_srs->srs_async); 1424 1425 mutex_exit(&mac_srs->srs_lock); 1426 } 1427 1428 /* 1429 * 'hint' is fanout_hint (type of uint64_t) which is given by the TCP/IP stack, 1430 * and it is used on the TX path. 1431 */ 1432 #define HASH_HINT(hint) \ 1433 ((hint) ^ ((hint) >> 24) ^ ((hint) >> 16) ^ ((hint) >> 8)) 1434 1435 1436 /* 1437 * hash based on the src address, dst address and the port information. 1438 */ 1439 #define HASH_ADDR(src, dst, ports) \ 1440 (ntohl((src) + (dst)) ^ ((ports) >> 24) ^ ((ports) >> 16) ^ \ 1441 ((ports) >> 8) ^ (ports)) 1442 1443 #define COMPUTE_INDEX(key, sz) (key % sz) 1444 1445 #define FANOUT_ENQUEUE_MP(head, tail, cnt, bw_ctl, sz, sz0, mp) { \ 1446 if ((tail) != NULL) { \ 1447 ASSERT((tail)->b_next == NULL); \ 1448 (tail)->b_next = (mp); \ 1449 } else { \ 1450 ASSERT((head) == NULL); \ 1451 (head) = (mp); \ 1452 } \ 1453 (tail) = (mp); \ 1454 (cnt)++; \ 1455 if ((bw_ctl)) \ 1456 (sz) += (sz0); \ 1457 } 1458 1459 #define MAC_FANOUT_DEFAULT 0 1460 #define MAC_FANOUT_RND_ROBIN 1 1461 int mac_fanout_type = MAC_FANOUT_DEFAULT; 1462 1463 #define MAX_SR_TYPES 3 1464 /* fanout types for port based hashing */ 1465 enum pkt_type { 1466 V4_TCP = 0, 1467 V4_UDP, 1468 OTH, 1469 UNDEF 1470 }; 1471 1472 /* 1473 * Pair of local and remote ports in the transport header 1474 */ 1475 #define PORTS_SIZE 4 1476 1477 /* 1478 * This routine delivers packets destined for an SRS into one of the 1479 * protocol soft rings. 1480 * 1481 * Given a chain of packets we need to split it up into multiple sub 1482 * chains: TCP, UDP or OTH soft ring. Instead of entering the soft 1483 * ring one packet at a time, we want to enter it in the form of a 1484 * chain otherwise we get this start/stop behaviour where the worker 1485 * thread goes to sleep and then next packet comes in forcing it to 1486 * wake up. 1487 */ 1488 static void 1489 mac_rx_srs_proto_fanout(mac_soft_ring_set_t *mac_srs, mblk_t *head) 1490 { 1491 struct ether_header *ehp; 1492 struct ether_vlan_header *evhp; 1493 uint32_t sap; 1494 ipha_t *ipha; 1495 uint8_t *dstaddr; 1496 size_t hdrsize; 1497 mblk_t *mp; 1498 mblk_t *headmp[MAX_SR_TYPES]; 1499 mblk_t *tailmp[MAX_SR_TYPES]; 1500 int cnt[MAX_SR_TYPES]; 1501 size_t sz[MAX_SR_TYPES]; 1502 size_t sz1; 1503 boolean_t bw_ctl; 1504 boolean_t hw_classified; 1505 boolean_t dls_bypass; 1506 boolean_t is_ether; 1507 boolean_t is_unicast; 1508 enum pkt_type type; 1509 mac_client_impl_t *mcip = mac_srs->srs_mcip; 1510 1511 is_ether = (mcip->mci_mip->mi_info.mi_nativemedia == DL_ETHER); 1512 bw_ctl = ((mac_srs->srs_type & SRST_BW_CONTROL) != 0); 1513 1514 /* 1515 * If we don't have a Rx ring, S/W classification would have done 1516 * its job and its a packet meant for us. If we were polling on 1517 * the default ring (i.e. there was a ring assigned to this SRS), 1518 * then we need to make sure that the mac address really belongs 1519 * to us. 1520 */ 1521 hw_classified = mac_srs->srs_ring != NULL && 1522 mac_srs->srs_ring->mr_classify_type == MAC_HW_CLASSIFIER; 1523 1524 /* 1525 * Some clients, such as non-ethernet, need DLS processing in 1526 * the Rx path. Such clients clear the SRST_DLS_BYPASS flag. 1527 * DLS bypass may also be disabled via the 1528 * MCIS_RX_BYPASS_DISABLE flag. 1529 */ 1530 dls_bypass = ((mac_srs->srs_type & SRST_DLS_BYPASS) != 0) && 1531 ((mcip->mci_state_flags & MCIS_RX_BYPASS_DISABLE) == 0); 1532 1533 bzero(headmp, MAX_SR_TYPES * sizeof (mblk_t *)); 1534 bzero(tailmp, MAX_SR_TYPES * sizeof (mblk_t *)); 1535 bzero(cnt, MAX_SR_TYPES * sizeof (int)); 1536 bzero(sz, MAX_SR_TYPES * sizeof (size_t)); 1537 1538 /* 1539 * We have a chain from SRS that we need to split across the 1540 * soft rings. The squeues for the TCP and IPv4 SAPs use their 1541 * own soft rings to allow polling from the squeue. The rest of 1542 * the packets are delivered on the OTH soft ring which cannot 1543 * be polled. 1544 */ 1545 while (head != NULL) { 1546 mp = head; 1547 head = head->b_next; 1548 mp->b_next = NULL; 1549 1550 type = OTH; 1551 sz1 = (mp->b_cont == NULL) ? MBLKL(mp) : msgdsize(mp); 1552 1553 if (is_ether) { 1554 /* 1555 * At this point we can be sure the packet at least 1556 * has an ether header. 1557 */ 1558 if (sz1 < sizeof (struct ether_header)) { 1559 mac_rx_drop_pkt(mac_srs, mp); 1560 continue; 1561 } 1562 ehp = (struct ether_header *)mp->b_rptr; 1563 1564 /* 1565 * Determine if this is a VLAN or non-VLAN packet. 1566 */ 1567 if ((sap = ntohs(ehp->ether_type)) == VLAN_TPID) { 1568 evhp = (struct ether_vlan_header *)mp->b_rptr; 1569 sap = ntohs(evhp->ether_type); 1570 hdrsize = sizeof (struct ether_vlan_header); 1571 1572 /* 1573 * Check if the VID of the packet, if 1574 * any, belongs to this client. 1575 * Technically, if this packet came up 1576 * via a HW classified ring then we 1577 * don't need to perform this check. 1578 * Perhaps a future optimization. 1579 */ 1580 if (!mac_client_check_flow_vid(mcip, 1581 VLAN_ID(ntohs(evhp->ether_tci)))) { 1582 mac_rx_drop_pkt(mac_srs, mp); 1583 continue; 1584 } 1585 } else { 1586 hdrsize = sizeof (struct ether_header); 1587 } 1588 is_unicast = 1589 ((((uint8_t *)&ehp->ether_dhost)[0] & 0x01) == 0); 1590 dstaddr = (uint8_t *)&ehp->ether_dhost; 1591 } else { 1592 mac_header_info_t mhi; 1593 1594 if (mac_header_info((mac_handle_t)mcip->mci_mip, 1595 mp, &mhi) != 0) { 1596 mac_rx_drop_pkt(mac_srs, mp); 1597 continue; 1598 } 1599 hdrsize = mhi.mhi_hdrsize; 1600 sap = mhi.mhi_bindsap; 1601 is_unicast = (mhi.mhi_dsttype == MAC_ADDRTYPE_UNICAST); 1602 dstaddr = (uint8_t *)mhi.mhi_daddr; 1603 } 1604 1605 if (!dls_bypass) { 1606 FANOUT_ENQUEUE_MP(headmp[type], tailmp[type], 1607 cnt[type], bw_ctl, sz[type], sz1, mp); 1608 continue; 1609 } 1610 1611 if (sap == ETHERTYPE_IP) { 1612 /* 1613 * If we are H/W classified, but we have promisc 1614 * on, then we need to check for the unicast address. 1615 */ 1616 if (hw_classified && mcip->mci_promisc_list != NULL) { 1617 mac_address_t *map; 1618 1619 rw_enter(&mcip->mci_rw_lock, RW_READER); 1620 map = mcip->mci_unicast; 1621 if (bcmp(dstaddr, map->ma_addr, 1622 map->ma_len) == 0) 1623 type = UNDEF; 1624 rw_exit(&mcip->mci_rw_lock); 1625 } else if (is_unicast) { 1626 type = UNDEF; 1627 } 1628 } 1629 1630 /* 1631 * This needs to become a contract with the driver for 1632 * the fast path. 1633 * 1634 * In the normal case the packet will have at least the L2 1635 * header and the IP + Transport header in the same mblk. 1636 * This is usually the case when the NIC driver sends up 1637 * the packet. This is also true when the stack generates 1638 * a packet that is looped back and when the stack uses the 1639 * fastpath mechanism. The normal case is optimized for 1640 * performance and may bypass DLS. All other cases go through 1641 * the 'OTH' type path without DLS bypass. 1642 */ 1643 ipha = (ipha_t *)(mp->b_rptr + hdrsize); 1644 if ((type != OTH) && MBLK_RX_FANOUT_SLOWPATH(mp, ipha)) 1645 type = OTH; 1646 1647 if (type == OTH) { 1648 FANOUT_ENQUEUE_MP(headmp[type], tailmp[type], 1649 cnt[type], bw_ctl, sz[type], sz1, mp); 1650 continue; 1651 } 1652 1653 ASSERT(type == UNDEF); 1654 1655 /* 1656 * Determine the type from the IP protocol value. If 1657 * classified as TCP or UDP, then update the read 1658 * pointer to the beginning of the IP header. 1659 * Otherwise leave the message as is for further 1660 * processing by DLS. 1661 */ 1662 switch (ipha->ipha_protocol) { 1663 case IPPROTO_TCP: 1664 type = V4_TCP; 1665 mp->b_rptr += hdrsize; 1666 break; 1667 case IPPROTO_UDP: 1668 type = V4_UDP; 1669 mp->b_rptr += hdrsize; 1670 break; 1671 default: 1672 type = OTH; 1673 break; 1674 } 1675 1676 FANOUT_ENQUEUE_MP(headmp[type], tailmp[type], cnt[type], 1677 bw_ctl, sz[type], sz1, mp); 1678 } 1679 1680 for (type = V4_TCP; type < UNDEF; type++) { 1681 if (headmp[type] != NULL) { 1682 mac_soft_ring_t *softring; 1683 1684 ASSERT(tailmp[type]->b_next == NULL); 1685 switch (type) { 1686 case V4_TCP: 1687 softring = mac_srs->srs_tcp_soft_rings[0]; 1688 break; 1689 case V4_UDP: 1690 softring = mac_srs->srs_udp_soft_rings[0]; 1691 break; 1692 case OTH: 1693 softring = mac_srs->srs_oth_soft_rings[0]; 1694 } 1695 mac_rx_soft_ring_process(mcip, softring, 1696 headmp[type], tailmp[type], cnt[type], sz[type]); 1697 } 1698 } 1699 } 1700 1701 int fanout_unaligned = 0; 1702 1703 /* 1704 * The fanout routine for any clients with DLS bypass disabled or for 1705 * traffic classified as "other". Returns -1 on an error (drop the 1706 * packet due to a malformed packet), 0 on success, with values 1707 * written in *indx and *type. 1708 */ 1709 static int 1710 mac_rx_srs_long_fanout(mac_soft_ring_set_t *mac_srs, mblk_t *mp, 1711 uint32_t sap, size_t hdrsize, enum pkt_type *type, uint_t *indx) 1712 { 1713 ip6_t *ip6h; 1714 ipha_t *ipha; 1715 uint8_t *whereptr; 1716 uint_t hash; 1717 uint16_t remlen; 1718 uint8_t nexthdr; 1719 uint16_t hdr_len; 1720 uint32_t src_val, dst_val; 1721 boolean_t modifiable = B_TRUE; 1722 boolean_t v6; 1723 1724 ASSERT(MBLKL(mp) >= hdrsize); 1725 1726 if (sap == ETHERTYPE_IPV6) { 1727 v6 = B_TRUE; 1728 hdr_len = IPV6_HDR_LEN; 1729 } else if (sap == ETHERTYPE_IP) { 1730 v6 = B_FALSE; 1731 hdr_len = IP_SIMPLE_HDR_LENGTH; 1732 } else { 1733 *indx = 0; 1734 *type = OTH; 1735 return (0); 1736 } 1737 1738 ip6h = (ip6_t *)(mp->b_rptr + hdrsize); 1739 ipha = (ipha_t *)ip6h; 1740 1741 if ((uint8_t *)ip6h == mp->b_wptr) { 1742 /* 1743 * The first mblk_t only includes the mac header. 1744 * Note that it is safe to change the mp pointer here, 1745 * as the subsequent operation does not assume mp 1746 * points to the start of the mac header. 1747 */ 1748 mp = mp->b_cont; 1749 1750 /* 1751 * Make sure the IP header points to an entire one. 1752 */ 1753 if (mp == NULL) 1754 return (-1); 1755 1756 if (MBLKL(mp) < hdr_len) { 1757 modifiable = (DB_REF(mp) == 1); 1758 1759 if (modifiable && !pullupmsg(mp, hdr_len)) 1760 return (-1); 1761 } 1762 1763 ip6h = (ip6_t *)mp->b_rptr; 1764 ipha = (ipha_t *)ip6h; 1765 } 1766 1767 if (!modifiable || !(OK_32PTR((char *)ip6h)) || 1768 ((uint8_t *)ip6h + hdr_len > mp->b_wptr)) { 1769 /* 1770 * If either the IP header is not aligned, or it does not hold 1771 * the complete simple structure (a pullupmsg() is not an 1772 * option since it would result in an unaligned IP header), 1773 * fanout to the default ring. 1774 * 1775 * Note that this may cause packet reordering. 1776 */ 1777 *indx = 0; 1778 *type = OTH; 1779 fanout_unaligned++; 1780 return (0); 1781 } 1782 1783 /* 1784 * Extract next-header, full header length, and source-hash value 1785 * using v4/v6 specific fields. 1786 */ 1787 if (v6) { 1788 remlen = ntohs(ip6h->ip6_plen); 1789 nexthdr = ip6h->ip6_nxt; 1790 src_val = V4_PART_OF_V6(ip6h->ip6_src); 1791 dst_val = V4_PART_OF_V6(ip6h->ip6_dst); 1792 /* 1793 * Do src based fanout if below tunable is set to B_TRUE or 1794 * when mac_ip_hdr_length_v6() fails because of malformed 1795 * packets or because mblks need to be concatenated using 1796 * pullupmsg(). 1797 * 1798 * Perform a version check to prevent parsing weirdness... 1799 */ 1800 if (IPH_HDR_VERSION(ip6h) != IPV6_VERSION || 1801 !mac_ip_hdr_length_v6(ip6h, mp->b_wptr, &hdr_len, &nexthdr, 1802 NULL)) { 1803 goto src_dst_based_fanout; 1804 } 1805 } else { 1806 hdr_len = IPH_HDR_LENGTH(ipha); 1807 remlen = ntohs(ipha->ipha_length) - hdr_len; 1808 nexthdr = ipha->ipha_protocol; 1809 src_val = (uint32_t)ipha->ipha_src; 1810 dst_val = (uint32_t)ipha->ipha_dst; 1811 /* 1812 * Catch IPv4 fragment case here. IPv6 has nexthdr == FRAG 1813 * for its equivalent case. 1814 */ 1815 if ((ntohs(ipha->ipha_fragment_offset_and_flags) & 1816 (IPH_MF | IPH_OFFSET)) != 0) { 1817 goto src_dst_based_fanout; 1818 } 1819 } 1820 if (remlen < MIN_EHDR_LEN) 1821 return (-1); 1822 whereptr = (uint8_t *)ip6h + hdr_len; 1823 1824 /* If the transport is one of below, we do port/SPI based fanout */ 1825 switch (nexthdr) { 1826 case IPPROTO_TCP: 1827 case IPPROTO_UDP: 1828 case IPPROTO_SCTP: 1829 case IPPROTO_ESP: 1830 /* 1831 * If the ports or SPI in the transport header is not part of 1832 * the mblk, do src_based_fanout, instead of calling 1833 * pullupmsg(). 1834 */ 1835 if (mp->b_cont == NULL || whereptr + PORTS_SIZE <= mp->b_wptr) 1836 break; /* out of switch... */ 1837 /* FALLTHRU */ 1838 default: 1839 goto src_dst_based_fanout; 1840 } 1841 1842 switch (nexthdr) { 1843 case IPPROTO_TCP: 1844 hash = HASH_ADDR(src_val, dst_val, *(uint32_t *)whereptr); 1845 *indx = COMPUTE_INDEX(hash, mac_srs->srs_tcp_ring_count); 1846 *type = OTH; 1847 break; 1848 case IPPROTO_UDP: 1849 case IPPROTO_SCTP: 1850 case IPPROTO_ESP: 1851 if (mac_fanout_type == MAC_FANOUT_DEFAULT) { 1852 hash = HASH_ADDR(src_val, dst_val, 1853 *(uint32_t *)whereptr); 1854 *indx = COMPUTE_INDEX(hash, 1855 mac_srs->srs_udp_ring_count); 1856 } else { 1857 *indx = mac_srs->srs_ind % mac_srs->srs_udp_ring_count; 1858 mac_srs->srs_ind++; 1859 } 1860 *type = OTH; 1861 break; 1862 } 1863 return (0); 1864 1865 src_dst_based_fanout: 1866 hash = HASH_ADDR(src_val, dst_val, (uint32_t)0); 1867 *indx = COMPUTE_INDEX(hash, mac_srs->srs_oth_ring_count); 1868 *type = OTH; 1869 return (0); 1870 } 1871 1872 /* 1873 * This routine delivers packets destined for an SRS into a soft ring member 1874 * of the set. 1875 * 1876 * Given a chain of packets we need to split it up into multiple sub 1877 * chains: TCP, UDP or OTH soft ring. Instead of entering the soft 1878 * ring one packet at a time, we want to enter it in the form of a 1879 * chain otherwise we get this start/stop behaviour where the worker 1880 * thread goes to sleep and then next packet comes in forcing it to 1881 * wake up. 1882 * 1883 * Note: 1884 * Since we know what is the maximum fanout possible, we create a 2D array 1885 * of 'softring types * MAX_SR_FANOUT' for the head, tail, cnt and sz 1886 * variables so that we can enter the softrings with chain. We need the 1887 * MAX_SR_FANOUT so we can allocate the arrays on the stack (a kmem_alloc 1888 * for each packet would be expensive). If we ever want to have the 1889 * ability to have unlimited fanout, we should probably declare a head, 1890 * tail, cnt, sz with each soft ring (a data struct which contains a softring 1891 * along with these members) and create an array of this uber struct so we 1892 * don't have to do kmem_alloc. 1893 */ 1894 int fanout_oth1 = 0; 1895 int fanout_oth2 = 0; 1896 int fanout_oth3 = 0; 1897 int fanout_oth4 = 0; 1898 int fanout_oth5 = 0; 1899 1900 static void 1901 mac_rx_srs_fanout(mac_soft_ring_set_t *mac_srs, mblk_t *head) 1902 { 1903 struct ether_header *ehp; 1904 struct ether_vlan_header *evhp; 1905 uint32_t sap; 1906 ipha_t *ipha; 1907 uint8_t *dstaddr; 1908 uint_t indx; 1909 size_t ports_offset; 1910 size_t ipha_len; 1911 size_t hdrsize; 1912 uint_t hash; 1913 mblk_t *mp; 1914 mblk_t *headmp[MAX_SR_TYPES][MAX_SR_FANOUT]; 1915 mblk_t *tailmp[MAX_SR_TYPES][MAX_SR_FANOUT]; 1916 int cnt[MAX_SR_TYPES][MAX_SR_FANOUT]; 1917 size_t sz[MAX_SR_TYPES][MAX_SR_FANOUT]; 1918 size_t sz1; 1919 boolean_t bw_ctl; 1920 boolean_t hw_classified; 1921 boolean_t dls_bypass; 1922 boolean_t is_ether; 1923 boolean_t is_unicast; 1924 int fanout_cnt; 1925 enum pkt_type type; 1926 mac_client_impl_t *mcip = mac_srs->srs_mcip; 1927 1928 is_ether = (mcip->mci_mip->mi_info.mi_nativemedia == DL_ETHER); 1929 bw_ctl = ((mac_srs->srs_type & SRST_BW_CONTROL) != 0); 1930 1931 /* 1932 * If we don't have a Rx ring, S/W classification would have done 1933 * its job and its a packet meant for us. If we were polling on 1934 * the default ring (i.e. there was a ring assigned to this SRS), 1935 * then we need to make sure that the mac address really belongs 1936 * to us. 1937 */ 1938 hw_classified = mac_srs->srs_ring != NULL && 1939 mac_srs->srs_ring->mr_classify_type == MAC_HW_CLASSIFIER; 1940 1941 /* 1942 * Some clients, such as non Ethernet, need DLS processing in 1943 * the Rx path. Such clients clear the SRST_DLS_BYPASS flag. 1944 * DLS bypass may also be disabled via the 1945 * MCIS_RX_BYPASS_DISABLE flag, but this is only consumed by 1946 * sun4v vsw currently. 1947 */ 1948 dls_bypass = ((mac_srs->srs_type & SRST_DLS_BYPASS) != 0) && 1949 ((mcip->mci_state_flags & MCIS_RX_BYPASS_DISABLE) == 0); 1950 1951 /* 1952 * Since the softrings are never destroyed and we always 1953 * create equal number of softrings for TCP, UDP and rest, 1954 * its OK to check one of them for count and use it without 1955 * any lock. In future, if soft rings get destroyed because 1956 * of reduction in fanout, we will need to ensure that happens 1957 * behind the SRS_PROC. 1958 */ 1959 fanout_cnt = mac_srs->srs_tcp_ring_count; 1960 1961 bzero(headmp, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (mblk_t *)); 1962 bzero(tailmp, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (mblk_t *)); 1963 bzero(cnt, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (int)); 1964 bzero(sz, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (size_t)); 1965 1966 /* 1967 * We got a chain from SRS that we need to send to the soft rings. 1968 * Since squeues for TCP & IPv4 SAP poll their soft rings (for 1969 * performance reasons), we need to separate out v4_tcp, v4_udp 1970 * and the rest goes in other. 1971 */ 1972 while (head != NULL) { 1973 mp = head; 1974 head = head->b_next; 1975 mp->b_next = NULL; 1976 1977 type = OTH; 1978 sz1 = (mp->b_cont == NULL) ? MBLKL(mp) : msgdsize(mp); 1979 1980 if (is_ether) { 1981 /* 1982 * At this point we can be sure the packet at least 1983 * has an ether header. 1984 */ 1985 if (sz1 < sizeof (struct ether_header)) { 1986 mac_rx_drop_pkt(mac_srs, mp); 1987 continue; 1988 } 1989 ehp = (struct ether_header *)mp->b_rptr; 1990 1991 /* 1992 * Determine if this is a VLAN or non-VLAN packet. 1993 */ 1994 if ((sap = ntohs(ehp->ether_type)) == VLAN_TPID) { 1995 evhp = (struct ether_vlan_header *)mp->b_rptr; 1996 sap = ntohs(evhp->ether_type); 1997 hdrsize = sizeof (struct ether_vlan_header); 1998 1999 /* 2000 * Check if the VID of the packet, if 2001 * any, belongs to this client. 2002 * Technically, if this packet came up 2003 * via a HW classified ring then we 2004 * don't need to perform this check. 2005 * Perhaps a future optimization. 2006 */ 2007 if (!mac_client_check_flow_vid(mcip, 2008 VLAN_ID(ntohs(evhp->ether_tci)))) { 2009 mac_rx_drop_pkt(mac_srs, mp); 2010 continue; 2011 } 2012 } else { 2013 hdrsize = sizeof (struct ether_header); 2014 } 2015 is_unicast = 2016 ((((uint8_t *)&ehp->ether_dhost)[0] & 0x01) == 0); 2017 dstaddr = (uint8_t *)&ehp->ether_dhost; 2018 } else { 2019 mac_header_info_t mhi; 2020 2021 if (mac_header_info((mac_handle_t)mcip->mci_mip, 2022 mp, &mhi) != 0) { 2023 mac_rx_drop_pkt(mac_srs, mp); 2024 continue; 2025 } 2026 hdrsize = mhi.mhi_hdrsize; 2027 sap = mhi.mhi_bindsap; 2028 is_unicast = (mhi.mhi_dsttype == MAC_ADDRTYPE_UNICAST); 2029 dstaddr = (uint8_t *)mhi.mhi_daddr; 2030 } 2031 2032 if (!dls_bypass) { 2033 if (mac_rx_srs_long_fanout(mac_srs, mp, sap, 2034 hdrsize, &type, &indx) == -1) { 2035 mac_rx_drop_pkt(mac_srs, mp); 2036 continue; 2037 } 2038 2039 FANOUT_ENQUEUE_MP(headmp[type][indx], 2040 tailmp[type][indx], cnt[type][indx], bw_ctl, 2041 sz[type][indx], sz1, mp); 2042 continue; 2043 } 2044 2045 /* 2046 * If we are using the default Rx ring where H/W or S/W 2047 * classification has not happened, we need to verify if 2048 * this unicast packet really belongs to us. 2049 */ 2050 if (sap == ETHERTYPE_IP) { 2051 /* 2052 * If we are H/W classified, but we have promisc 2053 * on, then we need to check for the unicast address. 2054 */ 2055 if (hw_classified && mcip->mci_promisc_list != NULL) { 2056 mac_address_t *map; 2057 2058 rw_enter(&mcip->mci_rw_lock, RW_READER); 2059 map = mcip->mci_unicast; 2060 if (bcmp(dstaddr, map->ma_addr, 2061 map->ma_len) == 0) 2062 type = UNDEF; 2063 rw_exit(&mcip->mci_rw_lock); 2064 } else if (is_unicast) { 2065 type = UNDEF; 2066 } 2067 } 2068 2069 /* 2070 * This needs to become a contract with the driver for 2071 * the fast path. 2072 */ 2073 2074 ipha = (ipha_t *)(mp->b_rptr + hdrsize); 2075 if ((type != OTH) && MBLK_RX_FANOUT_SLOWPATH(mp, ipha)) { 2076 type = OTH; 2077 fanout_oth1++; 2078 } 2079 2080 if (type != OTH) { 2081 uint16_t frag_offset_flags; 2082 2083 switch (ipha->ipha_protocol) { 2084 case IPPROTO_TCP: 2085 case IPPROTO_UDP: 2086 case IPPROTO_SCTP: 2087 case IPPROTO_ESP: 2088 ipha_len = IPH_HDR_LENGTH(ipha); 2089 if ((uchar_t *)ipha + ipha_len + PORTS_SIZE > 2090 mp->b_wptr) { 2091 type = OTH; 2092 break; 2093 } 2094 frag_offset_flags = 2095 ntohs(ipha->ipha_fragment_offset_and_flags); 2096 if ((frag_offset_flags & 2097 (IPH_MF | IPH_OFFSET)) != 0) { 2098 type = OTH; 2099 fanout_oth3++; 2100 break; 2101 } 2102 ports_offset = hdrsize + ipha_len; 2103 break; 2104 default: 2105 type = OTH; 2106 fanout_oth4++; 2107 break; 2108 } 2109 } 2110 2111 if (type == OTH) { 2112 if (mac_rx_srs_long_fanout(mac_srs, mp, sap, 2113 hdrsize, &type, &indx) == -1) { 2114 mac_rx_drop_pkt(mac_srs, mp); 2115 continue; 2116 } 2117 2118 FANOUT_ENQUEUE_MP(headmp[type][indx], 2119 tailmp[type][indx], cnt[type][indx], bw_ctl, 2120 sz[type][indx], sz1, mp); 2121 continue; 2122 } 2123 2124 ASSERT(type == UNDEF); 2125 2126 /* 2127 * XXX-Sunay: We should hold srs_lock since ring_count 2128 * below can change. But if we are always called from 2129 * mac_rx_srs_drain and SRS_PROC is set, then we can 2130 * enforce that ring_count can't be changed i.e. 2131 * to change fanout type or ring count, the calling 2132 * thread needs to be behind SRS_PROC. 2133 */ 2134 switch (ipha->ipha_protocol) { 2135 case IPPROTO_TCP: 2136 /* 2137 * Note that for ESP, we fanout on SPI and it is at the 2138 * same offset as the 2x16-bit ports. So it is clumped 2139 * along with TCP, UDP and SCTP. 2140 */ 2141 hash = HASH_ADDR(ipha->ipha_src, ipha->ipha_dst, 2142 *(uint32_t *)(mp->b_rptr + ports_offset)); 2143 indx = COMPUTE_INDEX(hash, mac_srs->srs_tcp_ring_count); 2144 type = V4_TCP; 2145 mp->b_rptr += hdrsize; 2146 break; 2147 case IPPROTO_UDP: 2148 case IPPROTO_SCTP: 2149 case IPPROTO_ESP: 2150 if (mac_fanout_type == MAC_FANOUT_DEFAULT) { 2151 hash = HASH_ADDR(ipha->ipha_src, ipha->ipha_dst, 2152 *(uint32_t *)(mp->b_rptr + ports_offset)); 2153 indx = COMPUTE_INDEX(hash, 2154 mac_srs->srs_udp_ring_count); 2155 } else { 2156 indx = mac_srs->srs_ind % 2157 mac_srs->srs_udp_ring_count; 2158 mac_srs->srs_ind++; 2159 } 2160 type = V4_UDP; 2161 mp->b_rptr += hdrsize; 2162 break; 2163 default: 2164 indx = 0; 2165 type = OTH; 2166 } 2167 2168 FANOUT_ENQUEUE_MP(headmp[type][indx], tailmp[type][indx], 2169 cnt[type][indx], bw_ctl, sz[type][indx], sz1, mp); 2170 } 2171 2172 for (type = V4_TCP; type < UNDEF; type++) { 2173 int i; 2174 2175 for (i = 0; i < fanout_cnt; i++) { 2176 if (headmp[type][i] != NULL) { 2177 mac_soft_ring_t *softring; 2178 2179 ASSERT(tailmp[type][i]->b_next == NULL); 2180 switch (type) { 2181 case V4_TCP: 2182 softring = 2183 mac_srs->srs_tcp_soft_rings[i]; 2184 break; 2185 case V4_UDP: 2186 softring = 2187 mac_srs->srs_udp_soft_rings[i]; 2188 break; 2189 case OTH: 2190 softring = 2191 mac_srs->srs_oth_soft_rings[i]; 2192 break; 2193 } 2194 mac_rx_soft_ring_process(mcip, 2195 softring, headmp[type][i], tailmp[type][i], 2196 cnt[type][i], sz[type][i]); 2197 } 2198 } 2199 } 2200 } 2201 2202 #define SRS_BYTES_TO_PICKUP 150000 2203 ssize_t max_bytes_to_pickup = SRS_BYTES_TO_PICKUP; 2204 2205 /* 2206 * mac_rx_srs_poll_ring 2207 * 2208 * This SRS Poll thread uses this routine to poll the underlying hardware 2209 * Rx ring to get a chain of packets. It can inline process that chain 2210 * if mac_latency_optimize is set (default) or signal the SRS worker thread 2211 * to do the remaining processing. 2212 * 2213 * Since packets come in the system via interrupt or poll path, we also 2214 * update the stats and deal with promiscous clients here. 2215 */ 2216 void 2217 mac_rx_srs_poll_ring(mac_soft_ring_set_t *mac_srs) 2218 { 2219 kmutex_t *lock = &mac_srs->srs_lock; 2220 kcondvar_t *async = &mac_srs->srs_cv; 2221 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx; 2222 mblk_t *head, *tail, *mp; 2223 callb_cpr_t cprinfo; 2224 ssize_t bytes_to_pickup; 2225 size_t sz; 2226 int count; 2227 mac_client_impl_t *smcip; 2228 2229 CALLB_CPR_INIT(&cprinfo, lock, callb_generic_cpr, "mac_srs_poll"); 2230 mutex_enter(lock); 2231 2232 start: 2233 for (;;) { 2234 if (mac_srs->srs_state & SRS_PAUSE) 2235 goto done; 2236 2237 CALLB_CPR_SAFE_BEGIN(&cprinfo); 2238 cv_wait(async, lock); 2239 CALLB_CPR_SAFE_END(&cprinfo, lock); 2240 2241 if (mac_srs->srs_state & SRS_PAUSE) 2242 goto done; 2243 2244 check_again: 2245 if (mac_srs->srs_type & SRST_BW_CONTROL) { 2246 /* 2247 * We pick as many bytes as we are allowed to queue. 2248 * Its possible that we will exceed the total 2249 * packets queued in case this SRS is part of the 2250 * Rx ring group since > 1 poll thread can be pulling 2251 * upto the max allowed packets at the same time 2252 * but that should be OK. 2253 */ 2254 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2255 bytes_to_pickup = 2256 mac_srs->srs_bw->mac_bw_drop_threshold - 2257 mac_srs->srs_bw->mac_bw_sz; 2258 /* 2259 * We shouldn't have been signalled if we 2260 * have 0 or less bytes to pick but since 2261 * some of the bytes accounting is driver 2262 * dependant, we do the safety check. 2263 */ 2264 if (bytes_to_pickup < 0) 2265 bytes_to_pickup = 0; 2266 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2267 } else { 2268 /* 2269 * ToDO: Need to change the polling API 2270 * to add a packet count and a flag which 2271 * tells the driver whether we want packets 2272 * based on a count, or bytes, or all the 2273 * packets queued in the driver/HW. This 2274 * way, we never have to check the limits 2275 * on poll path. We truly let only as many 2276 * packets enter the system as we are willing 2277 * to process or queue. 2278 * 2279 * Something along the lines of 2280 * pkts_to_pickup = mac_soft_ring_max_q_cnt - 2281 * mac_srs->srs_poll_pkt_cnt 2282 */ 2283 2284 /* 2285 * Since we are not doing B/W control, pick 2286 * as many packets as allowed. 2287 */ 2288 bytes_to_pickup = max_bytes_to_pickup; 2289 } 2290 2291 /* Poll the underlying Hardware */ 2292 mutex_exit(lock); 2293 head = MAC_HWRING_POLL(mac_srs->srs_ring, (int)bytes_to_pickup); 2294 mutex_enter(lock); 2295 2296 ASSERT((mac_srs->srs_state & SRS_POLL_THR_OWNER) == 2297 SRS_POLL_THR_OWNER); 2298 2299 mp = tail = head; 2300 count = 0; 2301 sz = 0; 2302 while (mp != NULL) { 2303 tail = mp; 2304 sz += msgdsize(mp); 2305 mp = mp->b_next; 2306 count++; 2307 } 2308 2309 if (head != NULL) { 2310 tail->b_next = NULL; 2311 smcip = mac_srs->srs_mcip; 2312 2313 SRS_RX_STAT_UPDATE(mac_srs, pollbytes, sz); 2314 SRS_RX_STAT_UPDATE(mac_srs, pollcnt, count); 2315 2316 /* 2317 * If there are any promiscuous mode callbacks 2318 * defined for this MAC client, pass them a copy 2319 * if appropriate and also update the counters. 2320 */ 2321 if (smcip != NULL) { 2322 if (smcip->mci_mip->mi_promisc_list != NULL) { 2323 mutex_exit(lock); 2324 mac_promisc_dispatch(smcip->mci_mip, 2325 head, NULL, B_FALSE); 2326 mutex_enter(lock); 2327 } 2328 } 2329 if (mac_srs->srs_type & SRST_BW_CONTROL) { 2330 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2331 mac_srs->srs_bw->mac_bw_polled += sz; 2332 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2333 } 2334 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, 2335 count, sz); 2336 if (count <= 10) 2337 srs_rx->sr_stat.mrs_chaincntundr10++; 2338 else if (count > 10 && count <= 50) 2339 srs_rx->sr_stat.mrs_chaincnt10to50++; 2340 else 2341 srs_rx->sr_stat.mrs_chaincntover50++; 2342 } 2343 2344 /* 2345 * We are guaranteed that SRS_PROC will be set if we 2346 * are here. Also, poll thread gets to run only if 2347 * the drain was being done by a worker thread although 2348 * its possible that worker thread is still running 2349 * and poll thread was sent down to keep the pipeline 2350 * going instead of doing a complete drain and then 2351 * trying to poll the NIC. 2352 * 2353 * So we need to check SRS_WORKER flag to make sure 2354 * that the worker thread is not processing the queue 2355 * in parallel to us. The flags and conditions are 2356 * protected by the srs_lock to prevent any race. We 2357 * ensure that we don't drop the srs_lock from now 2358 * till the end and similarly we don't drop the srs_lock 2359 * in mac_rx_srs_drain() till similar condition check 2360 * are complete. The mac_rx_srs_drain() needs to ensure 2361 * that SRS_WORKER flag remains set as long as its 2362 * processing the queue. 2363 */ 2364 if (!(mac_srs->srs_state & SRS_WORKER) && 2365 (mac_srs->srs_first != NULL)) { 2366 /* 2367 * We have packets to process and worker thread 2368 * is not running. Check to see if poll thread is 2369 * allowed to process. 2370 */ 2371 if (mac_srs->srs_state & SRS_LATENCY_OPT) { 2372 mac_srs->srs_drain_func(mac_srs, SRS_POLL_PROC); 2373 if (!(mac_srs->srs_state & SRS_PAUSE) && 2374 srs_rx->sr_poll_pkt_cnt <= 2375 srs_rx->sr_lowat) { 2376 srs_rx->sr_poll_again++; 2377 goto check_again; 2378 } 2379 /* 2380 * We are already above low water mark 2381 * so stay in the polling mode but no 2382 * need to poll. Once we dip below 2383 * the polling threshold, the processing 2384 * thread (soft ring) will signal us 2385 * to poll again (MAC_UPDATE_SRS_COUNT) 2386 */ 2387 srs_rx->sr_poll_drain_no_poll++; 2388 mac_srs->srs_state &= ~(SRS_PROC|SRS_GET_PKTS); 2389 /* 2390 * In B/W control case, its possible 2391 * that the backlog built up due to 2392 * B/W limit being reached and packets 2393 * are queued only in SRS. In this case, 2394 * we should schedule worker thread 2395 * since no one else will wake us up. 2396 */ 2397 if ((mac_srs->srs_type & SRST_BW_CONTROL) && 2398 (mac_srs->srs_tid == NULL)) { 2399 mac_srs->srs_tid = 2400 timeout(mac_srs_fire, mac_srs, 1); 2401 srs_rx->sr_poll_worker_wakeup++; 2402 } 2403 } else { 2404 /* 2405 * Wakeup the worker thread for more processing. 2406 * We optimize for throughput in this case. 2407 */ 2408 mac_srs->srs_state &= ~(SRS_PROC|SRS_GET_PKTS); 2409 MAC_SRS_WORKER_WAKEUP(mac_srs); 2410 srs_rx->sr_poll_sig_worker++; 2411 } 2412 } else if ((mac_srs->srs_first == NULL) && 2413 !(mac_srs->srs_state & SRS_WORKER)) { 2414 /* 2415 * There is nothing queued in SRS and 2416 * no worker thread running. Plus we 2417 * didn't get anything from the H/W 2418 * as well (head == NULL); 2419 */ 2420 ASSERT(head == NULL); 2421 mac_srs->srs_state &= 2422 ~(SRS_PROC|SRS_GET_PKTS); 2423 2424 /* 2425 * If we have a packets in soft ring, don't allow 2426 * more packets to come into this SRS by keeping the 2427 * interrupts off but not polling the H/W. The 2428 * poll thread will get signaled as soon as 2429 * srs_poll_pkt_cnt dips below poll threshold. 2430 */ 2431 if (srs_rx->sr_poll_pkt_cnt == 0) { 2432 srs_rx->sr_poll_intr_enable++; 2433 MAC_SRS_POLLING_OFF(mac_srs); 2434 } else { 2435 /* 2436 * We know nothing is queued in SRS 2437 * since we are here after checking 2438 * srs_first is NULL. The backlog 2439 * is entirely due to packets queued 2440 * in Soft ring which will wake us up 2441 * and get the interface out of polling 2442 * mode once the backlog dips below 2443 * sr_poll_thres. 2444 */ 2445 srs_rx->sr_poll_no_poll++; 2446 } 2447 } else { 2448 /* 2449 * Worker thread is already running. 2450 * Nothing much to do. If the polling 2451 * was enabled, worker thread will deal 2452 * with that. 2453 */ 2454 mac_srs->srs_state &= ~SRS_GET_PKTS; 2455 srs_rx->sr_poll_goto_sleep++; 2456 } 2457 } 2458 done: 2459 mac_srs->srs_state |= SRS_POLL_THR_QUIESCED; 2460 cv_signal(&mac_srs->srs_async); 2461 /* 2462 * If this is a temporary quiesce then wait for the restart signal 2463 * from the srs worker. Then clear the flags and signal the srs worker 2464 * to ensure a positive handshake and go back to start. 2465 */ 2466 while (!(mac_srs->srs_state & (SRS_CONDEMNED | SRS_POLL_THR_RESTART))) 2467 cv_wait(async, lock); 2468 if (mac_srs->srs_state & SRS_POLL_THR_RESTART) { 2469 ASSERT(!(mac_srs->srs_state & SRS_CONDEMNED)); 2470 mac_srs->srs_state &= 2471 ~(SRS_POLL_THR_QUIESCED | SRS_POLL_THR_RESTART); 2472 cv_signal(&mac_srs->srs_async); 2473 goto start; 2474 } else { 2475 mac_srs->srs_state |= SRS_POLL_THR_EXITED; 2476 cv_signal(&mac_srs->srs_async); 2477 CALLB_CPR_EXIT(&cprinfo); 2478 thread_exit(); 2479 } 2480 } 2481 2482 /* 2483 * mac_srs_pick_chain 2484 * 2485 * In Bandwidth control case, checks how many packets can be processed 2486 * and return them in a sub chain. 2487 */ 2488 static mblk_t * 2489 mac_srs_pick_chain(mac_soft_ring_set_t *mac_srs, mblk_t **chain_tail, 2490 size_t *chain_sz, int *chain_cnt) 2491 { 2492 mblk_t *head = NULL; 2493 mblk_t *tail = NULL; 2494 size_t sz; 2495 size_t tsz = 0; 2496 int cnt = 0; 2497 mblk_t *mp; 2498 2499 ASSERT(MUTEX_HELD(&mac_srs->srs_lock)); 2500 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2501 if (((mac_srs->srs_bw->mac_bw_used + mac_srs->srs_size) <= 2502 mac_srs->srs_bw->mac_bw_limit) || 2503 (mac_srs->srs_bw->mac_bw_limit == 0)) { 2504 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2505 head = mac_srs->srs_first; 2506 mac_srs->srs_first = NULL; 2507 *chain_tail = mac_srs->srs_last; 2508 mac_srs->srs_last = NULL; 2509 *chain_sz = mac_srs->srs_size; 2510 *chain_cnt = mac_srs->srs_count; 2511 mac_srs->srs_count = 0; 2512 mac_srs->srs_size = 0; 2513 return (head); 2514 } 2515 2516 /* 2517 * Can't clear the entire backlog. 2518 * Need to find how many packets to pick 2519 */ 2520 ASSERT(MUTEX_HELD(&mac_srs->srs_bw->mac_bw_lock)); 2521 while ((mp = mac_srs->srs_first) != NULL) { 2522 sz = msgdsize(mp); 2523 if ((tsz + sz + mac_srs->srs_bw->mac_bw_used) > 2524 mac_srs->srs_bw->mac_bw_limit) { 2525 if (!(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) 2526 mac_srs->srs_bw->mac_bw_state |= 2527 SRS_BW_ENFORCED; 2528 break; 2529 } 2530 2531 /* 2532 * The _size & cnt is decremented from the softrings 2533 * when they send up the packet for polling to work 2534 * properly. 2535 */ 2536 tsz += sz; 2537 cnt++; 2538 mac_srs->srs_count--; 2539 mac_srs->srs_size -= sz; 2540 if (tail != NULL) 2541 tail->b_next = mp; 2542 else 2543 head = mp; 2544 tail = mp; 2545 mac_srs->srs_first = mac_srs->srs_first->b_next; 2546 } 2547 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2548 if (mac_srs->srs_first == NULL) 2549 mac_srs->srs_last = NULL; 2550 2551 if (tail != NULL) 2552 tail->b_next = NULL; 2553 *chain_tail = tail; 2554 *chain_cnt = cnt; 2555 *chain_sz = tsz; 2556 2557 return (head); 2558 } 2559 2560 /* 2561 * mac_rx_srs_drain 2562 * 2563 * The SRS drain routine. Gets to run to clear the queue. Any thread 2564 * (worker, interrupt, poll) can call this based on processing model. 2565 * The first thing we do is disable interrupts if possible and then 2566 * drain the queue. we also try to poll the underlying hardware if 2567 * there is a dedicated hardware Rx ring assigned to this SRS. 2568 * 2569 * There is a equivalent drain routine in bandwidth control mode 2570 * mac_rx_srs_drain_bw. There is some code duplication between the two 2571 * routines but they are highly performance sensitive and are easier 2572 * to read/debug if they stay separate. Any code changes here might 2573 * also apply to mac_rx_srs_drain_bw as well. 2574 */ 2575 void 2576 mac_rx_srs_drain(mac_soft_ring_set_t *mac_srs, uint_t proc_type) 2577 { 2578 mblk_t *head; 2579 mblk_t *tail; 2580 timeout_id_t tid; 2581 int cnt = 0; 2582 mac_client_impl_t *mcip = mac_srs->srs_mcip; 2583 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx; 2584 2585 ASSERT(MUTEX_HELD(&mac_srs->srs_lock)); 2586 ASSERT(!(mac_srs->srs_type & SRST_BW_CONTROL)); 2587 2588 /* If we are blanked i.e. can't do upcalls, then we are done */ 2589 if (mac_srs->srs_state & (SRS_BLANK | SRS_PAUSE)) { 2590 ASSERT((mac_srs->srs_type & SRST_NO_SOFT_RINGS) || 2591 (mac_srs->srs_state & SRS_PAUSE)); 2592 goto out; 2593 } 2594 2595 if (mac_srs->srs_first == NULL) 2596 goto out; 2597 2598 if (!(mac_srs->srs_state & SRS_LATENCY_OPT) && 2599 (srs_rx->sr_poll_pkt_cnt <= srs_rx->sr_lowat)) { 2600 /* 2601 * In the normal case, the SRS worker thread does no 2602 * work and we wait for a backlog to build up before 2603 * we switch into polling mode. In case we are 2604 * optimizing for throughput, we use the worker thread 2605 * as well. The goal is to let worker thread process 2606 * the queue and poll thread to feed packets into 2607 * the queue. As such, we should signal the poll 2608 * thread to try and get more packets. 2609 * 2610 * We could have pulled this check in the POLL_RING 2611 * macro itself but keeping it explicit here makes 2612 * the architecture more human understandable. 2613 */ 2614 MAC_SRS_POLL_RING(mac_srs); 2615 } 2616 2617 again: 2618 head = mac_srs->srs_first; 2619 mac_srs->srs_first = NULL; 2620 tail = mac_srs->srs_last; 2621 mac_srs->srs_last = NULL; 2622 cnt = mac_srs->srs_count; 2623 mac_srs->srs_count = 0; 2624 2625 ASSERT(head != NULL); 2626 ASSERT(tail != NULL); 2627 2628 if ((tid = mac_srs->srs_tid) != NULL) 2629 mac_srs->srs_tid = NULL; 2630 2631 mac_srs->srs_state |= (SRS_PROC|proc_type); 2632 2633 /* 2634 * mcip is NULL for broadcast and multicast flows. The promisc 2635 * callbacks for broadcast and multicast packets are delivered from 2636 * mac_rx() and we don't need to worry about that case in this path 2637 */ 2638 if (mcip != NULL) { 2639 if (mcip->mci_promisc_list != NULL) { 2640 mutex_exit(&mac_srs->srs_lock); 2641 mac_promisc_client_dispatch(mcip, head); 2642 mutex_enter(&mac_srs->srs_lock); 2643 } 2644 if (MAC_PROTECT_ENABLED(mcip, MPT_IPNOSPOOF)) { 2645 mutex_exit(&mac_srs->srs_lock); 2646 mac_protect_intercept_dynamic(mcip, head); 2647 mutex_enter(&mac_srs->srs_lock); 2648 } 2649 } 2650 2651 /* 2652 * Check if SRS itself is doing the processing. This direct 2653 * path applies only when subflows are present. 2654 */ 2655 if (mac_srs->srs_type & SRST_NO_SOFT_RINGS) { 2656 mac_direct_rx_t proc; 2657 void *arg1; 2658 mac_resource_handle_t arg2; 2659 2660 /* 2661 * This is the case when a Rx is directly 2662 * assigned and we have a fully classified 2663 * protocol chain. We can deal with it in 2664 * one shot. 2665 */ 2666 proc = srs_rx->sr_func; 2667 arg1 = srs_rx->sr_arg1; 2668 arg2 = srs_rx->sr_arg2; 2669 2670 mac_srs->srs_state |= SRS_CLIENT_PROC; 2671 mutex_exit(&mac_srs->srs_lock); 2672 if (tid != NULL) { 2673 (void) untimeout(tid); 2674 tid = NULL; 2675 } 2676 2677 proc(arg1, arg2, head, NULL); 2678 /* 2679 * Decrement the size and count here itelf 2680 * since the packet has been processed. 2681 */ 2682 mutex_enter(&mac_srs->srs_lock); 2683 MAC_UPDATE_SRS_COUNT_LOCKED(mac_srs, cnt); 2684 if (mac_srs->srs_state & SRS_CLIENT_WAIT) 2685 cv_signal(&mac_srs->srs_client_cv); 2686 mac_srs->srs_state &= ~SRS_CLIENT_PROC; 2687 } else { 2688 /* Some kind of softrings based fanout is required */ 2689 mutex_exit(&mac_srs->srs_lock); 2690 if (tid != NULL) { 2691 (void) untimeout(tid); 2692 tid = NULL; 2693 } 2694 2695 /* 2696 * Since the fanout routines can deal with chains, 2697 * shoot the entire chain up. 2698 */ 2699 if (mac_srs->srs_type & SRST_FANOUT_SRC_IP) 2700 mac_rx_srs_fanout(mac_srs, head); 2701 else 2702 mac_rx_srs_proto_fanout(mac_srs, head); 2703 mutex_enter(&mac_srs->srs_lock); 2704 } 2705 2706 if (!(mac_srs->srs_state & (SRS_BLANK|SRS_PAUSE)) && 2707 (mac_srs->srs_first != NULL)) { 2708 /* 2709 * More packets arrived while we were clearing the 2710 * SRS. This can be possible because of one of 2711 * three conditions below: 2712 * 1) The driver is using multiple worker threads 2713 * to send the packets to us. 2714 * 2) The driver has a race in switching 2715 * between interrupt and polling mode or 2716 * 3) Packets are arriving in this SRS via the 2717 * S/W classification as well. 2718 * 2719 * We should switch to polling mode and see if we 2720 * need to send the poll thread down. Also, signal 2721 * the worker thread to process whats just arrived. 2722 */ 2723 MAC_SRS_POLLING_ON(mac_srs); 2724 if (srs_rx->sr_poll_pkt_cnt <= srs_rx->sr_lowat) { 2725 srs_rx->sr_drain_poll_sig++; 2726 MAC_SRS_POLL_RING(mac_srs); 2727 } 2728 2729 /* 2730 * If we didn't signal the poll thread, we need 2731 * to deal with the pending packets ourselves. 2732 */ 2733 if (proc_type == SRS_WORKER) { 2734 srs_rx->sr_drain_again++; 2735 goto again; 2736 } else { 2737 srs_rx->sr_drain_worker_sig++; 2738 cv_signal(&mac_srs->srs_async); 2739 } 2740 } 2741 2742 out: 2743 if (mac_srs->srs_state & SRS_GET_PKTS) { 2744 /* 2745 * Poll thread is already running. Leave the 2746 * SRS_RPOC set and hand over the control to 2747 * poll thread. 2748 */ 2749 mac_srs->srs_state &= ~proc_type; 2750 srs_rx->sr_drain_poll_running++; 2751 return; 2752 } 2753 2754 /* 2755 * Even if there are no packets queued in SRS, we 2756 * need to make sure that the shared counter is 2757 * clear and any associated softrings have cleared 2758 * all the backlog. Otherwise, leave the interface 2759 * in polling mode and the poll thread will get 2760 * signalled once the count goes down to zero. 2761 * 2762 * If someone is already draining the queue (SRS_PROC is 2763 * set) when the srs_poll_pkt_cnt goes down to zero, 2764 * then it means that drain is already running and we 2765 * will turn off polling at that time if there is 2766 * no backlog. 2767 * 2768 * As long as there are packets queued either 2769 * in soft ring set or its soft rings, we will leave 2770 * the interface in polling mode (even if the drain 2771 * was done being the interrupt thread). We signal 2772 * the poll thread as well if we have dipped below 2773 * low water mark. 2774 * 2775 * NOTE: We can't use the MAC_SRS_POLLING_ON macro 2776 * since that turn polling on only for worker thread. 2777 * Its not worth turning polling on for interrupt 2778 * thread (since NIC will not issue another interrupt) 2779 * unless a backlog builds up. 2780 */ 2781 if ((srs_rx->sr_poll_pkt_cnt > 0) && 2782 (mac_srs->srs_state & SRS_POLLING_CAPAB)) { 2783 mac_srs->srs_state &= ~(SRS_PROC|proc_type); 2784 srs_rx->sr_drain_keep_polling++; 2785 MAC_SRS_POLLING_ON(mac_srs); 2786 if (srs_rx->sr_poll_pkt_cnt <= srs_rx->sr_lowat) 2787 MAC_SRS_POLL_RING(mac_srs); 2788 return; 2789 } 2790 2791 /* Nothing else to do. Get out of poll mode */ 2792 MAC_SRS_POLLING_OFF(mac_srs); 2793 mac_srs->srs_state &= ~(SRS_PROC|proc_type); 2794 srs_rx->sr_drain_finish_intr++; 2795 } 2796 2797 /* 2798 * mac_rx_srs_drain_bw 2799 * 2800 * The SRS BW drain routine. Gets to run to clear the queue. Any thread 2801 * (worker, interrupt, poll) can call this based on processing model. 2802 * The first thing we do is disable interrupts if possible and then 2803 * drain the queue. we also try to poll the underlying hardware if 2804 * there is a dedicated hardware Rx ring assigned to this SRS. 2805 * 2806 * There is a equivalent drain routine in non bandwidth control mode 2807 * mac_rx_srs_drain. There is some code duplication between the two 2808 * routines but they are highly performance sensitive and are easier 2809 * to read/debug if they stay separate. Any code changes here might 2810 * also apply to mac_rx_srs_drain as well. 2811 */ 2812 void 2813 mac_rx_srs_drain_bw(mac_soft_ring_set_t *mac_srs, uint_t proc_type) 2814 { 2815 mblk_t *head; 2816 mblk_t *tail; 2817 timeout_id_t tid; 2818 size_t sz = 0; 2819 int cnt = 0; 2820 mac_client_impl_t *mcip = mac_srs->srs_mcip; 2821 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx; 2822 clock_t now; 2823 2824 ASSERT(MUTEX_HELD(&mac_srs->srs_lock)); 2825 ASSERT(mac_srs->srs_type & SRST_BW_CONTROL); 2826 again: 2827 /* Check if we are doing B/W control */ 2828 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2829 now = ddi_get_lbolt(); 2830 if (mac_srs->srs_bw->mac_bw_curr_time != now) { 2831 mac_srs->srs_bw->mac_bw_curr_time = now; 2832 mac_srs->srs_bw->mac_bw_used = 0; 2833 if (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) 2834 mac_srs->srs_bw->mac_bw_state &= ~SRS_BW_ENFORCED; 2835 } else if (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) { 2836 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2837 goto done; 2838 } else if (mac_srs->srs_bw->mac_bw_used > 2839 mac_srs->srs_bw->mac_bw_limit) { 2840 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED; 2841 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2842 goto done; 2843 } 2844 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2845 2846 /* If we are blanked i.e. can't do upcalls, then we are done */ 2847 if (mac_srs->srs_state & (SRS_BLANK | SRS_PAUSE)) { 2848 ASSERT((mac_srs->srs_type & SRST_NO_SOFT_RINGS) || 2849 (mac_srs->srs_state & SRS_PAUSE)); 2850 goto done; 2851 } 2852 2853 sz = 0; 2854 cnt = 0; 2855 if ((head = mac_srs_pick_chain(mac_srs, &tail, &sz, &cnt)) == NULL) { 2856 /* 2857 * We couldn't pick up a single packet. 2858 */ 2859 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2860 if ((mac_srs->srs_bw->mac_bw_used == 0) && 2861 (mac_srs->srs_size != 0) && 2862 !(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) { 2863 /* 2864 * Seems like configured B/W doesn't 2865 * even allow processing of 1 packet 2866 * per tick. 2867 * 2868 * XXX: raise the limit to processing 2869 * at least 1 packet per tick. 2870 */ 2871 mac_srs->srs_bw->mac_bw_limit += 2872 mac_srs->srs_bw->mac_bw_limit; 2873 mac_srs->srs_bw->mac_bw_drop_threshold += 2874 mac_srs->srs_bw->mac_bw_drop_threshold; 2875 cmn_err(CE_NOTE, "mac_rx_srs_drain: srs(%p) " 2876 "raised B/W limit to %d since not even a " 2877 "single packet can be processed per " 2878 "tick %d\n", (void *)mac_srs, 2879 (int)mac_srs->srs_bw->mac_bw_limit, 2880 (int)msgdsize(mac_srs->srs_first)); 2881 } 2882 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2883 goto done; 2884 } 2885 2886 ASSERT(head != NULL); 2887 ASSERT(tail != NULL); 2888 2889 /* zero bandwidth: drop all and return to interrupt mode */ 2890 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 2891 if (mac_srs->srs_bw->mac_bw_limit == 0) { 2892 srs_rx->sr_stat.mrs_sdrops += cnt; 2893 ASSERT(mac_srs->srs_bw->mac_bw_sz >= sz); 2894 mac_srs->srs_bw->mac_bw_sz -= sz; 2895 mac_srs->srs_bw->mac_bw_drop_bytes += sz; 2896 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2897 mac_drop_chain(head, "Rx no bandwidth"); 2898 goto leave_poll; 2899 } else { 2900 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 2901 } 2902 2903 if ((tid = mac_srs->srs_tid) != NULL) 2904 mac_srs->srs_tid = NULL; 2905 2906 mac_srs->srs_state |= (SRS_PROC|proc_type); 2907 MAC_SRS_WORKER_POLLING_ON(mac_srs); 2908 2909 /* 2910 * mcip is NULL for broadcast and multicast flows. The promisc 2911 * callbacks for broadcast and multicast packets are delivered from 2912 * mac_rx() and we don't need to worry about that case in this path 2913 */ 2914 if (mcip != NULL) { 2915 if (mcip->mci_promisc_list != NULL) { 2916 mutex_exit(&mac_srs->srs_lock); 2917 mac_promisc_client_dispatch(mcip, head); 2918 mutex_enter(&mac_srs->srs_lock); 2919 } 2920 if (MAC_PROTECT_ENABLED(mcip, MPT_IPNOSPOOF)) { 2921 mutex_exit(&mac_srs->srs_lock); 2922 mac_protect_intercept_dynamic(mcip, head); 2923 mutex_enter(&mac_srs->srs_lock); 2924 } 2925 } 2926 2927 /* 2928 * Check if SRS itself is doing the processing 2929 * This direct path does not apply when subflows are present. In this 2930 * case, packets need to be dispatched to a soft ring according to the 2931 * flow's bandwidth and other resources contraints. 2932 */ 2933 if (mac_srs->srs_type & SRST_NO_SOFT_RINGS) { 2934 mac_direct_rx_t proc; 2935 void *arg1; 2936 mac_resource_handle_t arg2; 2937 2938 /* 2939 * This is the case when a Rx is directly 2940 * assigned and we have a fully classified 2941 * protocol chain. We can deal with it in 2942 * one shot. 2943 */ 2944 proc = srs_rx->sr_func; 2945 arg1 = srs_rx->sr_arg1; 2946 arg2 = srs_rx->sr_arg2; 2947 2948 mac_srs->srs_state |= SRS_CLIENT_PROC; 2949 mutex_exit(&mac_srs->srs_lock); 2950 if (tid != NULL) { 2951 (void) untimeout(tid); 2952 tid = NULL; 2953 } 2954 2955 proc(arg1, arg2, head, NULL); 2956 /* 2957 * Decrement the size and count here itelf 2958 * since the packet has been processed. 2959 */ 2960 mutex_enter(&mac_srs->srs_lock); 2961 MAC_UPDATE_SRS_COUNT_LOCKED(mac_srs, cnt); 2962 MAC_UPDATE_SRS_SIZE_LOCKED(mac_srs, sz); 2963 2964 if (mac_srs->srs_state & SRS_CLIENT_WAIT) 2965 cv_signal(&mac_srs->srs_client_cv); 2966 mac_srs->srs_state &= ~SRS_CLIENT_PROC; 2967 } else { 2968 /* Some kind of softrings based fanout is required */ 2969 mutex_exit(&mac_srs->srs_lock); 2970 if (tid != NULL) { 2971 (void) untimeout(tid); 2972 tid = NULL; 2973 } 2974 2975 /* 2976 * Since the fanout routines can deal with chains, 2977 * shoot the entire chain up. 2978 */ 2979 if (mac_srs->srs_type & SRST_FANOUT_SRC_IP) 2980 mac_rx_srs_fanout(mac_srs, head); 2981 else 2982 mac_rx_srs_proto_fanout(mac_srs, head); 2983 mutex_enter(&mac_srs->srs_lock); 2984 } 2985 2986 /* 2987 * Send the poll thread to pick up any packets arrived 2988 * so far. This also serves as the last check in case 2989 * nothing else is queued in the SRS. The poll thread 2990 * is signalled only in the case the drain was done 2991 * by the worker thread and SRS_WORKER is set. The 2992 * worker thread can run in parallel as long as the 2993 * SRS_WORKER flag is set. We we have nothing else to 2994 * process, we can exit while leaving SRS_PROC set 2995 * which gives the poll thread control to process and 2996 * cleanup once it returns from the NIC. 2997 * 2998 * If we have nothing else to process, we need to 2999 * ensure that we keep holding the srs_lock till 3000 * all the checks below are done and control is 3001 * handed to the poll thread if it was running. 3002 */ 3003 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 3004 if (!(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) { 3005 if (mac_srs->srs_first != NULL) { 3006 if (proc_type == SRS_WORKER) { 3007 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 3008 if (srs_rx->sr_poll_pkt_cnt <= 3009 srs_rx->sr_lowat) 3010 MAC_SRS_POLL_RING(mac_srs); 3011 goto again; 3012 } else { 3013 cv_signal(&mac_srs->srs_async); 3014 } 3015 } 3016 } 3017 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 3018 3019 done: 3020 3021 if (mac_srs->srs_state & SRS_GET_PKTS) { 3022 /* 3023 * Poll thread is already running. Leave the 3024 * SRS_RPOC set and hand over the control to 3025 * poll thread. 3026 */ 3027 mac_srs->srs_state &= ~proc_type; 3028 return; 3029 } 3030 3031 /* 3032 * If we can't process packets because we have exceeded 3033 * B/W limit for this tick, just set the timeout 3034 * and leave. 3035 * 3036 * Even if there are no packets queued in SRS, we 3037 * need to make sure that the shared counter is 3038 * clear and any associated softrings have cleared 3039 * all the backlog. Otherwise, leave the interface 3040 * in polling mode and the poll thread will get 3041 * signalled once the count goes down to zero. 3042 * 3043 * If someone is already draining the queue (SRS_PROC is 3044 * set) when the srs_poll_pkt_cnt goes down to zero, 3045 * then it means that drain is already running and we 3046 * will turn off polling at that time if there is 3047 * no backlog. As long as there are packets queued either 3048 * is soft ring set or its soft rings, we will leave 3049 * the interface in polling mode. 3050 */ 3051 mutex_enter(&mac_srs->srs_bw->mac_bw_lock); 3052 if ((mac_srs->srs_state & SRS_POLLING_CAPAB) && 3053 ((mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) || 3054 (srs_rx->sr_poll_pkt_cnt > 0))) { 3055 MAC_SRS_POLLING_ON(mac_srs); 3056 mac_srs->srs_state &= ~(SRS_PROC|proc_type); 3057 if ((mac_srs->srs_first != NULL) && 3058 (mac_srs->srs_tid == NULL)) 3059 mac_srs->srs_tid = timeout(mac_srs_fire, 3060 mac_srs, 1); 3061 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 3062 return; 3063 } 3064 mutex_exit(&mac_srs->srs_bw->mac_bw_lock); 3065 3066 leave_poll: 3067 3068 /* Nothing else to do. Get out of poll mode */ 3069 MAC_SRS_POLLING_OFF(mac_srs); 3070 mac_srs->srs_state &= ~(SRS_PROC|proc_type); 3071 } 3072 3073 /* 3074 * mac_srs_worker 3075 * 3076 * The SRS worker routine. Drains the queue when no one else is 3077 * processing it. 3078 */ 3079 void 3080 mac_srs_worker(mac_soft_ring_set_t *mac_srs) 3081 { 3082 kmutex_t *lock = &mac_srs->srs_lock; 3083 kcondvar_t *async = &mac_srs->srs_async; 3084 callb_cpr_t cprinfo; 3085 boolean_t bw_ctl_flag; 3086 3087 CALLB_CPR_INIT(&cprinfo, lock, callb_generic_cpr, "srs_worker"); 3088 mutex_enter(lock); 3089 3090 start: 3091 for (;;) { 3092 bw_ctl_flag = B_FALSE; 3093 if (mac_srs->srs_type & SRST_BW_CONTROL) { 3094 MAC_SRS_BW_LOCK(mac_srs); 3095 MAC_SRS_CHECK_BW_CONTROL(mac_srs); 3096 if (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) 3097 bw_ctl_flag = B_TRUE; 3098 MAC_SRS_BW_UNLOCK(mac_srs); 3099 } 3100 /* 3101 * The SRS_BW_ENFORCED flag may change since we have dropped 3102 * the mac_bw_lock. However the drain function can handle both 3103 * a drainable SRS or a bandwidth controlled SRS, and the 3104 * effect of scheduling a timeout is to wakeup the worker 3105 * thread which in turn will call the drain function. Since 3106 * we release the srs_lock atomically only in the cv_wait there 3107 * isn't a fear of waiting for ever. 3108 */ 3109 while (((mac_srs->srs_state & SRS_PROC) || 3110 (mac_srs->srs_first == NULL) || bw_ctl_flag || 3111 (mac_srs->srs_state & SRS_TX_BLOCKED)) && 3112 !(mac_srs->srs_state & SRS_PAUSE)) { 3113 /* 3114 * If we have packets queued and we are here 3115 * because B/W control is in place, we better 3116 * schedule the worker wakeup after 1 tick 3117 * to see if bandwidth control can be relaxed. 3118 */ 3119 if (bw_ctl_flag && mac_srs->srs_tid == NULL) { 3120 /* 3121 * We need to ensure that a timer is already 3122 * scheduled or we force schedule one for 3123 * later so that we can continue processing 3124 * after this quanta is over. 3125 */ 3126 mac_srs->srs_tid = timeout(mac_srs_fire, 3127 mac_srs, 1); 3128 } 3129 wait: 3130 CALLB_CPR_SAFE_BEGIN(&cprinfo); 3131 cv_wait(async, lock); 3132 CALLB_CPR_SAFE_END(&cprinfo, lock); 3133 3134 if (mac_srs->srs_state & SRS_PAUSE) 3135 goto done; 3136 if (mac_srs->srs_state & SRS_PROC) 3137 goto wait; 3138 3139 if (mac_srs->srs_first != NULL && 3140 mac_srs->srs_type & SRST_BW_CONTROL) { 3141 MAC_SRS_BW_LOCK(mac_srs); 3142 if (mac_srs->srs_bw->mac_bw_state & 3143 SRS_BW_ENFORCED) { 3144 MAC_SRS_CHECK_BW_CONTROL(mac_srs); 3145 } 3146 bw_ctl_flag = mac_srs->srs_bw->mac_bw_state & 3147 SRS_BW_ENFORCED; 3148 MAC_SRS_BW_UNLOCK(mac_srs); 3149 } 3150 } 3151 3152 if (mac_srs->srs_state & SRS_PAUSE) 3153 goto done; 3154 mac_srs->srs_drain_func(mac_srs, SRS_WORKER); 3155 } 3156 done: 3157 /* 3158 * The Rx SRS quiesce logic first cuts off packet supply to the SRS 3159 * from both hard and soft classifications and waits for such threads 3160 * to finish before signaling the worker. So at this point the only 3161 * thread left that could be competing with the worker is the poll 3162 * thread. In the case of Tx, there shouldn't be any thread holding 3163 * SRS_PROC at this point. 3164 */ 3165 if (!(mac_srs->srs_state & SRS_PROC)) { 3166 mac_srs->srs_state |= SRS_PROC; 3167 } else { 3168 ASSERT((mac_srs->srs_type & SRST_TX) == 0); 3169 /* 3170 * Poll thread still owns the SRS and is still running 3171 */ 3172 ASSERT((mac_srs->srs_poll_thr == NULL) || 3173 ((mac_srs->srs_state & SRS_POLL_THR_OWNER) == 3174 SRS_POLL_THR_OWNER)); 3175 } 3176 mac_srs_worker_quiesce(mac_srs); 3177 /* 3178 * Wait for the SRS_RESTART or SRS_CONDEMNED signal from the initiator 3179 * of the quiesce operation 3180 */ 3181 while (!(mac_srs->srs_state & (SRS_CONDEMNED | SRS_RESTART))) 3182 cv_wait(&mac_srs->srs_async, &mac_srs->srs_lock); 3183 3184 if (mac_srs->srs_state & SRS_RESTART) { 3185 ASSERT(!(mac_srs->srs_state & SRS_CONDEMNED)); 3186 mac_srs_worker_restart(mac_srs); 3187 mac_srs->srs_state &= ~SRS_PROC; 3188 goto start; 3189 } 3190 3191 if (!(mac_srs->srs_state & SRS_CONDEMNED_DONE)) 3192 mac_srs_worker_quiesce(mac_srs); 3193 3194 mac_srs->srs_state &= ~SRS_PROC; 3195 /* The macro drops the srs_lock */ 3196 CALLB_CPR_EXIT(&cprinfo); 3197 thread_exit(); 3198 } 3199 3200 /* 3201 * mac_rx_srs_subflow_process 3202 * 3203 * Receive side routine called from interrupt path when there are 3204 * sub flows present on this SRS. 3205 */ 3206 /* ARGSUSED */ 3207 void 3208 mac_rx_srs_subflow_process(void *arg, mac_resource_handle_t srs, 3209 mblk_t *mp_chain, boolean_t loopback) 3210 { 3211 flow_entry_t *flent = NULL; 3212 flow_entry_t *prev_flent = NULL; 3213 mblk_t *mp = NULL; 3214 mblk_t *tail = NULL; 3215 mac_soft_ring_set_t *mac_srs = (mac_soft_ring_set_t *)srs; 3216 mac_client_impl_t *mcip; 3217 3218 mcip = mac_srs->srs_mcip; 3219 ASSERT(mcip != NULL); 3220 3221 /* 3222 * We need to determine the SRS for every packet 3223 * by walking the flow table, if we don't get any, 3224 * then we proceed using the SRS we came with. 3225 */ 3226 mp = tail = mp_chain; 3227 while (mp != NULL) { 3228 3229 /* 3230 * We will increment the stats for the mactching subflow. 3231 * when we get the bytes/pkt count for the classified packets 3232 * later in mac_rx_srs_process. 3233 */ 3234 (void) mac_flow_lookup(mcip->mci_subflow_tab, mp, 3235 FLOW_INBOUND, &flent); 3236 3237 if (mp == mp_chain || flent == prev_flent) { 3238 if (prev_flent != NULL) 3239 FLOW_REFRELE(prev_flent); 3240 prev_flent = flent; 3241 flent = NULL; 3242 tail = mp; 3243 mp = mp->b_next; 3244 continue; 3245 } 3246 tail->b_next = NULL; 3247 /* 3248 * A null indicates, this is for the mac_srs itself. 3249 * XXX-venu : probably assert for fe_rx_srs_cnt == 0. 3250 */ 3251 if (prev_flent == NULL || prev_flent->fe_rx_srs_cnt == 0) { 3252 mac_rx_srs_process(arg, 3253 (mac_resource_handle_t)mac_srs, mp_chain, 3254 loopback); 3255 } else { 3256 (prev_flent->fe_cb_fn)(prev_flent->fe_cb_arg1, 3257 prev_flent->fe_cb_arg2, mp_chain, loopback); 3258 FLOW_REFRELE(prev_flent); 3259 } 3260 prev_flent = flent; 3261 flent = NULL; 3262 mp_chain = mp; 3263 tail = mp; 3264 mp = mp->b_next; 3265 } 3266 /* Last chain */ 3267 ASSERT(mp_chain != NULL); 3268 if (prev_flent == NULL || prev_flent->fe_rx_srs_cnt == 0) { 3269 mac_rx_srs_process(arg, 3270 (mac_resource_handle_t)mac_srs, mp_chain, loopback); 3271 } else { 3272 (prev_flent->fe_cb_fn)(prev_flent->fe_cb_arg1, 3273 prev_flent->fe_cb_arg2, mp_chain, loopback); 3274 FLOW_REFRELE(prev_flent); 3275 } 3276 } 3277 3278 /* 3279 * MAC SRS receive side routine. If the data is coming from the 3280 * network (i.e. from a NIC) then this is called in interrupt context. 3281 * If the data is coming from a local sender (e.g. mac_tx_send() or 3282 * bridge_forward()) then this is not called in interrupt context. 3283 * 3284 * loopback is set to force a context switch on the loopback 3285 * path between MAC clients. 3286 */ 3287 /* ARGSUSED */ 3288 void 3289 mac_rx_srs_process(void *arg, mac_resource_handle_t srs, mblk_t *mp_chain, 3290 boolean_t loopback) 3291 { 3292 mac_soft_ring_set_t *mac_srs = (mac_soft_ring_set_t *)srs; 3293 mblk_t *mp, *tail, *head; 3294 int count = 0; 3295 int count1; 3296 size_t sz = 0; 3297 size_t chain_sz, sz1; 3298 mac_bw_ctl_t *mac_bw; 3299 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx; 3300 3301 /* 3302 * Set the tail, count and sz. We set the sz irrespective 3303 * of whether we are doing B/W control or not for the 3304 * purpose of updating the stats. 3305 */ 3306 mp = tail = mp_chain; 3307 while (mp != NULL) { 3308 tail = mp; 3309 count++; 3310 sz += msgdsize(mp); 3311 mp = mp->b_next; 3312 } 3313 3314 mutex_enter(&mac_srs->srs_lock); 3315 3316 if (loopback) { 3317 SRS_RX_STAT_UPDATE(mac_srs, lclbytes, sz); 3318 SRS_RX_STAT_UPDATE(mac_srs, lclcnt, count); 3319 3320 } else { 3321 SRS_RX_STAT_UPDATE(mac_srs, intrbytes, sz); 3322 SRS_RX_STAT_UPDATE(mac_srs, intrcnt, count); 3323 } 3324 3325 /* 3326 * If the SRS in already being processed; has been blanked; 3327 * can be processed by worker thread only; or the B/W limit 3328 * has been reached, then queue the chain and check if 3329 * worker thread needs to be awakend. 3330 */ 3331 if (mac_srs->srs_type & SRST_BW_CONTROL) { 3332 mac_bw = mac_srs->srs_bw; 3333 ASSERT(mac_bw != NULL); 3334 mutex_enter(&mac_bw->mac_bw_lock); 3335 mac_bw->mac_bw_intr += sz; 3336 if (mac_bw->mac_bw_limit == 0) { 3337 /* zero bandwidth: drop all */ 3338 srs_rx->sr_stat.mrs_sdrops += count; 3339 mac_bw->mac_bw_drop_bytes += sz; 3340 mutex_exit(&mac_bw->mac_bw_lock); 3341 mutex_exit(&mac_srs->srs_lock); 3342 mac_drop_chain(mp_chain, "Rx no bandwidth"); 3343 return; 3344 } else { 3345 if ((mac_bw->mac_bw_sz + sz) <= 3346 mac_bw->mac_bw_drop_threshold) { 3347 mutex_exit(&mac_bw->mac_bw_lock); 3348 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, mp_chain, 3349 tail, count, sz); 3350 } else { 3351 mp = mp_chain; 3352 chain_sz = 0; 3353 count1 = 0; 3354 tail = NULL; 3355 head = NULL; 3356 while (mp != NULL) { 3357 sz1 = msgdsize(mp); 3358 if (mac_bw->mac_bw_sz + chain_sz + sz1 > 3359 mac_bw->mac_bw_drop_threshold) 3360 break; 3361 chain_sz += sz1; 3362 count1++; 3363 tail = mp; 3364 mp = mp->b_next; 3365 } 3366 mutex_exit(&mac_bw->mac_bw_lock); 3367 if (tail != NULL) { 3368 head = tail->b_next; 3369 tail->b_next = NULL; 3370 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, 3371 mp_chain, tail, count1, chain_sz); 3372 sz -= chain_sz; 3373 count -= count1; 3374 } else { 3375 /* Can't pick up any */ 3376 head = mp_chain; 3377 } 3378 if (head != NULL) { 3379 /* Drop any packet over the threshold */ 3380 srs_rx->sr_stat.mrs_sdrops += count; 3381 mutex_enter(&mac_bw->mac_bw_lock); 3382 mac_bw->mac_bw_drop_bytes += sz; 3383 mutex_exit(&mac_bw->mac_bw_lock); 3384 freemsgchain(head); 3385 } 3386 } 3387 MAC_SRS_WORKER_WAKEUP(mac_srs); 3388 mutex_exit(&mac_srs->srs_lock); 3389 return; 3390 } 3391 } 3392 3393 /* 3394 * If the total number of packets queued in the SRS and 3395 * its associated soft rings exceeds the max allowed, 3396 * then drop the chain. If we are polling capable, this 3397 * shouldn't be happening. 3398 */ 3399 if (!(mac_srs->srs_type & SRST_BW_CONTROL) && 3400 (srs_rx->sr_poll_pkt_cnt > srs_rx->sr_hiwat)) { 3401 mac_bw = mac_srs->srs_bw; 3402 srs_rx->sr_stat.mrs_sdrops += count; 3403 mutex_enter(&mac_bw->mac_bw_lock); 3404 mac_bw->mac_bw_drop_bytes += sz; 3405 mutex_exit(&mac_bw->mac_bw_lock); 3406 freemsgchain(mp_chain); 3407 mutex_exit(&mac_srs->srs_lock); 3408 return; 3409 } 3410 3411 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, mp_chain, tail, count, sz); 3412 3413 if (!(mac_srs->srs_state & SRS_PROC)) { 3414 /* 3415 * If we are coming via loopback, if we are not optimizing for 3416 * latency, or if our stack is running deep, we should signal 3417 * the worker thread. 3418 */ 3419 if (loopback || !(mac_srs->srs_state & SRS_LATENCY_OPT) || 3420 MAC_RX_SRS_TOODEEP()) { 3421 /* 3422 * For loopback, We need to let the worker take 3423 * over as we don't want to continue in the same 3424 * thread even if we can. This could lead to stack 3425 * overflows and may also end up using 3426 * resources (cpu) incorrectly. 3427 */ 3428 cv_signal(&mac_srs->srs_async); 3429 } else { 3430 /* 3431 * Seems like no one is processing the SRS and 3432 * there is no backlog. We also inline process 3433 * our packet if its a single packet in non 3434 * latency optimized case (in latency optimized 3435 * case, we inline process chains of any size). 3436 */ 3437 mac_srs->srs_drain_func(mac_srs, SRS_PROC_FAST); 3438 } 3439 } 3440 mutex_exit(&mac_srs->srs_lock); 3441 } 3442 3443 /* TX SIDE ROUTINES (RUNTIME) */ 3444 3445 /* 3446 * mac_tx_srs_no_desc 3447 * 3448 * This routine is called by Tx single ring default mode 3449 * when Tx ring runs out of descs. 3450 */ 3451 mac_tx_cookie_t 3452 mac_tx_srs_no_desc(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3453 uint16_t flag, mblk_t **ret_mp) 3454 { 3455 mac_tx_cookie_t cookie = 0; 3456 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 3457 boolean_t wakeup_worker = B_TRUE; 3458 uint32_t tx_mode = srs_tx->st_mode; 3459 int cnt, sz; 3460 mblk_t *tail; 3461 3462 ASSERT(tx_mode == SRS_TX_DEFAULT || tx_mode == SRS_TX_BW); 3463 if (flag & MAC_DROP_ON_NO_DESC) { 3464 MAC_TX_SRS_DROP_MESSAGE(mac_srs, mp_chain, cookie, 3465 "Tx no desc"); 3466 } else { 3467 if (mac_srs->srs_first != NULL) 3468 wakeup_worker = B_FALSE; 3469 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 3470 if (flag & MAC_TX_NO_ENQUEUE) { 3471 /* 3472 * If TX_QUEUED is not set, queue the 3473 * packet and let mac_tx_srs_drain() 3474 * set the TX_BLOCKED bit for the 3475 * reasons explained above. Otherwise, 3476 * return the mblks. 3477 */ 3478 if (wakeup_worker) { 3479 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, 3480 mp_chain, tail, cnt, sz); 3481 } else { 3482 MAC_TX_SET_NO_ENQUEUE(mac_srs, 3483 mp_chain, ret_mp, cookie); 3484 } 3485 } else { 3486 MAC_TX_SRS_TEST_HIWAT(mac_srs, mp_chain, 3487 tail, cnt, sz, cookie); 3488 } 3489 if (wakeup_worker) 3490 cv_signal(&mac_srs->srs_async); 3491 } 3492 return (cookie); 3493 } 3494 3495 /* 3496 * mac_tx_srs_enqueue 3497 * 3498 * This routine is called when Tx SRS is operating in either serializer 3499 * or bandwidth mode. In serializer mode, a packet will get enqueued 3500 * when a thread cannot enter SRS exclusively. In bandwidth mode, 3501 * packets gets queued if allowed byte-count limit for a tick is 3502 * exceeded. The action that gets taken when MAC_DROP_ON_NO_DESC and 3503 * MAC_TX_NO_ENQUEUE is set is different than when operaing in either 3504 * the default mode or fanout mode. Here packets get dropped or 3505 * returned back to the caller only after hi-watermark worth of data 3506 * is queued. 3507 */ 3508 static mac_tx_cookie_t 3509 mac_tx_srs_enqueue(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3510 uint16_t flag, uintptr_t fanout_hint, mblk_t **ret_mp) 3511 { 3512 mac_tx_cookie_t cookie = 0; 3513 int cnt, sz; 3514 mblk_t *tail; 3515 boolean_t wakeup_worker = B_TRUE; 3516 3517 /* 3518 * Ignore fanout hint if we don't have multiple tx rings. 3519 */ 3520 if (!MAC_TX_SOFT_RINGS(mac_srs)) 3521 fanout_hint = 0; 3522 3523 if (mac_srs->srs_first != NULL) 3524 wakeup_worker = B_FALSE; 3525 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 3526 if (flag & MAC_DROP_ON_NO_DESC) { 3527 if (mac_srs->srs_count > mac_srs->srs_tx.st_hiwat) { 3528 MAC_TX_SRS_DROP_MESSAGE(mac_srs, mp_chain, cookie, 3529 "Tx SRS hiwat"); 3530 } else { 3531 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, 3532 mp_chain, tail, cnt, sz); 3533 } 3534 } else if (flag & MAC_TX_NO_ENQUEUE) { 3535 if ((mac_srs->srs_count > mac_srs->srs_tx.st_hiwat) || 3536 (mac_srs->srs_state & SRS_TX_WAKEUP_CLIENT)) { 3537 MAC_TX_SET_NO_ENQUEUE(mac_srs, mp_chain, 3538 ret_mp, cookie); 3539 } else { 3540 mp_chain->b_prev = (mblk_t *)fanout_hint; 3541 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, 3542 mp_chain, tail, cnt, sz); 3543 } 3544 } else { 3545 /* 3546 * If you are BW_ENFORCED, just enqueue the 3547 * packet. srs_worker will drain it at the 3548 * prescribed rate. Before enqueueing, save 3549 * the fanout hint. 3550 */ 3551 mp_chain->b_prev = (mblk_t *)fanout_hint; 3552 MAC_TX_SRS_TEST_HIWAT(mac_srs, mp_chain, 3553 tail, cnt, sz, cookie); 3554 } 3555 if (wakeup_worker) 3556 cv_signal(&mac_srs->srs_async); 3557 return (cookie); 3558 } 3559 3560 /* 3561 * There are seven tx modes: 3562 * 3563 * 1) Default mode (SRS_TX_DEFAULT) 3564 * 2) Serialization mode (SRS_TX_SERIALIZE) 3565 * 3) Fanout mode (SRS_TX_FANOUT) 3566 * 4) Bandwdith mode (SRS_TX_BW) 3567 * 5) Fanout and Bandwidth mode (SRS_TX_BW_FANOUT) 3568 * 6) aggr Tx mode (SRS_TX_AGGR) 3569 * 7) aggr Tx bw mode (SRS_TX_BW_AGGR) 3570 * 3571 * The tx mode in which an SRS operates is decided in mac_tx_srs_setup() 3572 * based on the number of Tx rings requested for an SRS and whether 3573 * bandwidth control is requested or not. 3574 * 3575 * The default mode (i.e., no fanout/no bandwidth) is used when the 3576 * underlying NIC does not have Tx rings or just one Tx ring. In this mode, 3577 * the SRS acts as a pass-thru. Packets will go directly to mac_tx_send(). 3578 * When the underlying Tx ring runs out of Tx descs, it starts queueing up 3579 * packets in SRS. When flow-control is relieved, the srs_worker drains 3580 * the queued packets and informs blocked clients to restart sending 3581 * packets. 3582 * 3583 * In the SRS_TX_SERIALIZE mode, all calls to mac_tx() are serialized. This 3584 * mode is used when the link has no Tx rings or only one Tx ring. 3585 * 3586 * In the SRS_TX_FANOUT mode, packets will be fanned out to multiple 3587 * Tx rings. Each Tx ring will have a soft ring associated with it. 3588 * These soft rings will be hung off the Tx SRS. Queueing if it happens 3589 * due to lack of Tx desc will be in individual soft ring (and not srs) 3590 * associated with Tx ring. 3591 * 3592 * In the TX_BW mode, tx srs will allow packets to go down to Tx ring 3593 * only if bw is available. Otherwise the packets will be queued in 3594 * SRS. If fanout to multiple Tx rings is configured, the packets will 3595 * be fanned out among the soft rings associated with the Tx rings. 3596 * 3597 * In SRS_TX_AGGR mode, mac_tx_aggr_mode() routine is called. This routine 3598 * invokes an aggr function, aggr_find_tx_ring(), to find a pseudo Tx ring 3599 * belonging to a port on which the packet has to be sent. Aggr will 3600 * always have a pseudo Tx ring associated with it even when it is an 3601 * aggregation over a single NIC that has no Tx rings. Even in such a 3602 * case, the single pseudo Tx ring will have a soft ring associated with 3603 * it and the soft ring will hang off the SRS. 3604 * 3605 * If a bandwidth is specified for an aggr, SRS_TX_BW_AGGR mode is used. 3606 * In this mode, the bandwidth is first applied on the outgoing packets 3607 * and later mac_tx_addr_mode() function is called to send the packet out 3608 * of one of the pseudo Tx rings. 3609 * 3610 * Four flags are used in srs_state for indicating flow control 3611 * conditions : SRS_TX_BLOCKED, SRS_TX_HIWAT, SRS_TX_WAKEUP_CLIENT. 3612 * SRS_TX_BLOCKED indicates out of Tx descs. SRS expects a wakeup from the 3613 * driver below. 3614 * SRS_TX_HIWAT indicates packet count enqueued in Tx SRS exceeded Tx hiwat 3615 * and flow-control pressure is applied back to clients. The clients expect 3616 * wakeup when flow-control is relieved. 3617 * SRS_TX_WAKEUP_CLIENT get set when (flag == MAC_TX_NO_ENQUEUE) and mblk 3618 * got returned back to client either due to lack of Tx descs or due to bw 3619 * control reasons. The clients expect a wakeup when condition is relieved. 3620 * 3621 * The fourth argument to mac_tx() is the flag. Normally it will be 0 but 3622 * some clients set the following values too: MAC_DROP_ON_NO_DESC, 3623 * MAC_TX_NO_ENQUEUE 3624 * Mac clients that do not want packets to be enqueued in the mac layer set 3625 * MAC_DROP_ON_NO_DESC value. The packets won't be queued in the Tx SRS or 3626 * Tx soft rings but instead get dropped when the NIC runs out of desc. The 3627 * behaviour of this flag is different when the Tx is running in serializer 3628 * or bandwidth mode. Under these (Serializer, bandwidth) modes, the packet 3629 * get dropped when Tx high watermark is reached. 3630 * There are some mac clients like vsw, aggr that want the mblks to be 3631 * returned back to clients instead of being queued in Tx SRS (or Tx soft 3632 * rings) under flow-control (i.e., out of desc or exceeding bw limits) 3633 * conditions. These clients call mac_tx() with MAC_TX_NO_ENQUEUE flag set. 3634 * In the default and Tx fanout mode, the un-transmitted mblks will be 3635 * returned back to the clients when the driver runs out of Tx descs. 3636 * SRS_TX_WAKEUP_CLIENT (or S_RING_WAKEUP_CLIENT) will be set in SRS (or 3637 * soft ring) so that the clients can be woken up when Tx desc become 3638 * available. When running in serializer or bandwidth mode mode, 3639 * SRS_TX_WAKEUP_CLIENT will be set when tx hi-watermark is reached. 3640 */ 3641 3642 mac_tx_func_t 3643 mac_tx_get_func(uint32_t mode) 3644 { 3645 return (mac_tx_mode_list[mode].mac_tx_func); 3646 } 3647 3648 /* ARGSUSED */ 3649 static mac_tx_cookie_t 3650 mac_tx_single_ring_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3651 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 3652 { 3653 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 3654 mac_tx_stats_t stats; 3655 mac_tx_cookie_t cookie = 0; 3656 3657 ASSERT(srs_tx->st_mode == SRS_TX_DEFAULT); 3658 3659 /* Regular case with a single Tx ring */ 3660 /* 3661 * SRS_TX_BLOCKED is set when underlying NIC runs 3662 * out of Tx descs and messages start getting 3663 * queued. It won't get reset until 3664 * tx_srs_drain() completely drains out the 3665 * messages. 3666 */ 3667 if ((mac_srs->srs_state & SRS_ENQUEUED) != 0) { 3668 /* Tx descs/resources not available */ 3669 mutex_enter(&mac_srs->srs_lock); 3670 if ((mac_srs->srs_state & SRS_ENQUEUED) != 0) { 3671 cookie = mac_tx_srs_no_desc(mac_srs, mp_chain, 3672 flag, ret_mp); 3673 mutex_exit(&mac_srs->srs_lock); 3674 return (cookie); 3675 } 3676 /* 3677 * While we were computing mblk count, the 3678 * flow control condition got relieved. 3679 * Continue with the transmission. 3680 */ 3681 mutex_exit(&mac_srs->srs_lock); 3682 } 3683 3684 mp_chain = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 3685 mp_chain, &stats); 3686 3687 /* 3688 * Multiple threads could be here sending packets. 3689 * Under such conditions, it is not possible to 3690 * automically set SRS_TX_BLOCKED bit to indicate 3691 * out of tx desc condition. To atomically set 3692 * this, we queue the returned packet and do 3693 * the setting of SRS_TX_BLOCKED in 3694 * mac_tx_srs_drain(). 3695 */ 3696 if (mp_chain != NULL) { 3697 mutex_enter(&mac_srs->srs_lock); 3698 cookie = mac_tx_srs_no_desc(mac_srs, mp_chain, flag, ret_mp); 3699 mutex_exit(&mac_srs->srs_lock); 3700 return (cookie); 3701 } 3702 SRS_TX_STATS_UPDATE(mac_srs, &stats); 3703 3704 return (0); 3705 } 3706 3707 /* 3708 * mac_tx_serialize_mode 3709 * 3710 * This is an experimental mode implemented as per the request of PAE. 3711 * In this mode, all callers attempting to send a packet to the NIC 3712 * will get serialized. Only one thread at any time will access the 3713 * NIC to send the packet out. 3714 */ 3715 /* ARGSUSED */ 3716 static mac_tx_cookie_t 3717 mac_tx_serializer_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3718 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 3719 { 3720 mac_tx_stats_t stats; 3721 mac_tx_cookie_t cookie = 0; 3722 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 3723 3724 /* Single ring, serialize below */ 3725 ASSERT(srs_tx->st_mode == SRS_TX_SERIALIZE); 3726 mutex_enter(&mac_srs->srs_lock); 3727 if ((mac_srs->srs_first != NULL) || 3728 (mac_srs->srs_state & SRS_PROC)) { 3729 /* 3730 * In serialization mode, queue all packets until 3731 * TX_HIWAT is set. 3732 * If drop bit is set, drop if TX_HIWAT is set. 3733 * If no_enqueue is set, still enqueue until hiwat 3734 * is set and return mblks after TX_HIWAT is set. 3735 */ 3736 cookie = mac_tx_srs_enqueue(mac_srs, mp_chain, 3737 flag, 0, ret_mp); 3738 mutex_exit(&mac_srs->srs_lock); 3739 return (cookie); 3740 } 3741 /* 3742 * No packets queued, nothing on proc and no flow 3743 * control condition. Fast-path, ok. Do inline 3744 * processing. 3745 */ 3746 mac_srs->srs_state |= SRS_PROC; 3747 mutex_exit(&mac_srs->srs_lock); 3748 3749 mp_chain = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 3750 mp_chain, &stats); 3751 3752 mutex_enter(&mac_srs->srs_lock); 3753 mac_srs->srs_state &= ~SRS_PROC; 3754 if (mp_chain != NULL) { 3755 cookie = mac_tx_srs_enqueue(mac_srs, 3756 mp_chain, flag, 0, ret_mp); 3757 } 3758 if (mac_srs->srs_first != NULL) { 3759 /* 3760 * We processed inline our packet and a new 3761 * packet/s got queued while we were 3762 * processing. Wakeup srs worker 3763 */ 3764 cv_signal(&mac_srs->srs_async); 3765 } 3766 mutex_exit(&mac_srs->srs_lock); 3767 3768 if (cookie == 0) 3769 SRS_TX_STATS_UPDATE(mac_srs, &stats); 3770 3771 return (cookie); 3772 } 3773 3774 /* 3775 * mac_tx_fanout_mode 3776 * 3777 * In this mode, the SRS will have access to multiple Tx rings to send 3778 * the packet out. The fanout hint that is passed as an argument is 3779 * used to find an appropriate ring to fanout the traffic. Each Tx 3780 * ring, in turn, will have a soft ring associated with it. If a Tx 3781 * ring runs out of Tx desc's the returned packet will be queued in 3782 * the soft ring associated with that Tx ring. The srs itself will not 3783 * queue any packets. 3784 */ 3785 3786 #define MAC_TX_SOFT_RING_PROCESS(chain) { \ 3787 index = COMPUTE_INDEX(hash, mac_srs->srs_tx_ring_count), \ 3788 softring = mac_srs->srs_tx_soft_rings[index]; \ 3789 cookie = mac_tx_soft_ring_process(softring, chain, flag, ret_mp); \ 3790 DTRACE_PROBE2(tx__fanout, uint64_t, hash, uint_t, index); \ 3791 } 3792 3793 static mac_tx_cookie_t 3794 mac_tx_fanout_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3795 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 3796 { 3797 mac_soft_ring_t *softring; 3798 uint64_t hash; 3799 uint_t index; 3800 mac_tx_cookie_t cookie = 0; 3801 3802 ASSERT(mac_srs->srs_tx.st_mode == SRS_TX_FANOUT || 3803 mac_srs->srs_tx.st_mode == SRS_TX_BW_FANOUT); 3804 if (fanout_hint != 0) { 3805 /* 3806 * The hint is specified by the caller, simply pass the 3807 * whole chain to the soft ring. 3808 */ 3809 hash = HASH_HINT(fanout_hint); 3810 MAC_TX_SOFT_RING_PROCESS(mp_chain); 3811 } else { 3812 mblk_t *last_mp, *cur_mp, *sub_chain; 3813 uint64_t last_hash = 0; 3814 uint_t media = mac_srs->srs_mcip->mci_mip->mi_info.mi_media; 3815 3816 /* 3817 * Compute the hash from the contents (headers) of the 3818 * packets of the mblk chain. Split the chains into 3819 * subchains of the same conversation. 3820 * 3821 * Since there may be more than one ring used for 3822 * sub-chains of the same call, and since the caller 3823 * does not maintain per conversation state since it 3824 * passed a zero hint, unsent subchains will be 3825 * dropped. 3826 */ 3827 3828 flag |= MAC_DROP_ON_NO_DESC; 3829 ret_mp = NULL; 3830 3831 ASSERT(ret_mp == NULL); 3832 3833 sub_chain = NULL; 3834 last_mp = NULL; 3835 3836 for (cur_mp = mp_chain; cur_mp != NULL; 3837 cur_mp = cur_mp->b_next) { 3838 hash = mac_pkt_hash(media, cur_mp, MAC_PKT_HASH_L4, 3839 B_TRUE); 3840 if (last_hash != 0 && hash != last_hash) { 3841 /* 3842 * Starting a different subchain, send current 3843 * chain out. 3844 */ 3845 ASSERT(last_mp != NULL); 3846 last_mp->b_next = NULL; 3847 MAC_TX_SOFT_RING_PROCESS(sub_chain); 3848 sub_chain = NULL; 3849 } 3850 3851 /* add packet to subchain */ 3852 if (sub_chain == NULL) 3853 sub_chain = cur_mp; 3854 last_mp = cur_mp; 3855 last_hash = hash; 3856 } 3857 3858 if (sub_chain != NULL) { 3859 /* send last subchain */ 3860 ASSERT(last_mp != NULL); 3861 last_mp->b_next = NULL; 3862 MAC_TX_SOFT_RING_PROCESS(sub_chain); 3863 } 3864 3865 cookie = 0; 3866 } 3867 3868 return (cookie); 3869 } 3870 3871 /* 3872 * mac_tx_bw_mode 3873 * 3874 * In the bandwidth mode, Tx srs will allow packets to go down to Tx ring 3875 * only if bw is available. Otherwise the packets will be queued in 3876 * SRS. If the SRS has multiple Tx rings, then packets will get fanned 3877 * out to a Tx rings. 3878 */ 3879 static mac_tx_cookie_t 3880 mac_tx_bw_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 3881 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 3882 { 3883 int cnt, sz; 3884 mblk_t *tail; 3885 mac_tx_cookie_t cookie = 0; 3886 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 3887 clock_t now; 3888 3889 ASSERT(TX_BANDWIDTH_MODE(mac_srs)); 3890 ASSERT(mac_srs->srs_type & SRST_BW_CONTROL); 3891 mutex_enter(&mac_srs->srs_lock); 3892 if (mac_srs->srs_bw->mac_bw_limit == 0) { 3893 /* 3894 * zero bandwidth, no traffic is sent: drop the packets, 3895 * or return the whole chain if the caller requests all 3896 * unsent packets back. 3897 */ 3898 if (flag & MAC_TX_NO_ENQUEUE) { 3899 cookie = (mac_tx_cookie_t)mac_srs; 3900 *ret_mp = mp_chain; 3901 } else { 3902 MAC_TX_SRS_DROP_MESSAGE(mac_srs, mp_chain, cookie, 3903 "Tx no bandwidth"); 3904 } 3905 mutex_exit(&mac_srs->srs_lock); 3906 return (cookie); 3907 } else if ((mac_srs->srs_first != NULL) || 3908 (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) { 3909 cookie = mac_tx_srs_enqueue(mac_srs, mp_chain, flag, 3910 fanout_hint, ret_mp); 3911 mutex_exit(&mac_srs->srs_lock); 3912 return (cookie); 3913 } 3914 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 3915 now = ddi_get_lbolt(); 3916 if (mac_srs->srs_bw->mac_bw_curr_time != now) { 3917 mac_srs->srs_bw->mac_bw_curr_time = now; 3918 mac_srs->srs_bw->mac_bw_used = 0; 3919 } else if (mac_srs->srs_bw->mac_bw_used > 3920 mac_srs->srs_bw->mac_bw_limit) { 3921 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED; 3922 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, 3923 mp_chain, tail, cnt, sz); 3924 /* 3925 * Wakeup worker thread. Note that worker 3926 * thread has to be woken up so that it 3927 * can fire up the timer to be woken up 3928 * on the next tick. Also once 3929 * BW_ENFORCED is set, it can only be 3930 * reset by srs_worker thread. Until then 3931 * all packets will get queued up in SRS 3932 * and hence this this code path won't be 3933 * entered until BW_ENFORCED is reset. 3934 */ 3935 cv_signal(&mac_srs->srs_async); 3936 mutex_exit(&mac_srs->srs_lock); 3937 return (cookie); 3938 } 3939 3940 mac_srs->srs_bw->mac_bw_used += sz; 3941 mutex_exit(&mac_srs->srs_lock); 3942 3943 if (srs_tx->st_mode == SRS_TX_BW_FANOUT) { 3944 mac_soft_ring_t *softring; 3945 uint_t indx, hash; 3946 3947 hash = HASH_HINT(fanout_hint); 3948 indx = COMPUTE_INDEX(hash, 3949 mac_srs->srs_tx_ring_count); 3950 softring = mac_srs->srs_tx_soft_rings[indx]; 3951 return (mac_tx_soft_ring_process(softring, mp_chain, flag, 3952 ret_mp)); 3953 } else if (srs_tx->st_mode == SRS_TX_BW_AGGR) { 3954 return (mac_tx_aggr_mode(mac_srs, mp_chain, 3955 fanout_hint, flag, ret_mp)); 3956 } else { 3957 mac_tx_stats_t stats; 3958 3959 mp_chain = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 3960 mp_chain, &stats); 3961 3962 if (mp_chain != NULL) { 3963 mutex_enter(&mac_srs->srs_lock); 3964 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 3965 if (mac_srs->srs_bw->mac_bw_used > sz) 3966 mac_srs->srs_bw->mac_bw_used -= sz; 3967 else 3968 mac_srs->srs_bw->mac_bw_used = 0; 3969 cookie = mac_tx_srs_enqueue(mac_srs, mp_chain, flag, 3970 fanout_hint, ret_mp); 3971 mutex_exit(&mac_srs->srs_lock); 3972 return (cookie); 3973 } 3974 SRS_TX_STATS_UPDATE(mac_srs, &stats); 3975 3976 return (0); 3977 } 3978 } 3979 3980 /* 3981 * mac_tx_aggr_mode 3982 * 3983 * This routine invokes an aggr function, aggr_find_tx_ring(), to find 3984 * a (pseudo) Tx ring belonging to a port on which the packet has to 3985 * be sent. aggr_find_tx_ring() first finds the outgoing port based on 3986 * L2/L3/L4 policy and then uses the fanout_hint passed to it to pick 3987 * a Tx ring from the selected port. 3988 * 3989 * Note that a port can be deleted from the aggregation. In such a case, 3990 * the aggregation layer first separates the port from the rest of the 3991 * ports making sure that port (and thus any Tx rings associated with 3992 * it) won't get selected in the call to aggr_find_tx_ring() function. 3993 * Later calls are made to mac_group_rem_ring() passing pseudo Tx ring 3994 * handles one by one which in turn will quiesce the Tx SRS and remove 3995 * the soft ring associated with the pseudo Tx ring. Unlike Rx side 3996 * where a cookie is used to protect against mac_rx_ring() calls on 3997 * rings that have been removed, no such cookie is needed on the Tx 3998 * side as the pseudo Tx ring won't be available anymore to 3999 * aggr_find_tx_ring() once the port has been removed. 4000 */ 4001 static mac_tx_cookie_t 4002 mac_tx_aggr_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain, 4003 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp) 4004 { 4005 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 4006 mac_tx_ring_fn_t find_tx_ring_fn; 4007 mac_ring_handle_t ring = NULL; 4008 void *arg; 4009 mac_soft_ring_t *sringp; 4010 4011 find_tx_ring_fn = srs_tx->st_capab_aggr.mca_find_tx_ring_fn; 4012 arg = srs_tx->st_capab_aggr.mca_arg; 4013 if (find_tx_ring_fn(arg, mp_chain, fanout_hint, &ring) == NULL) 4014 return (0); 4015 sringp = srs_tx->st_soft_rings[((mac_ring_t *)ring)->mr_index]; 4016 return (mac_tx_soft_ring_process(sringp, mp_chain, flag, ret_mp)); 4017 } 4018 4019 void 4020 mac_tx_invoke_callbacks(mac_client_impl_t *mcip, mac_tx_cookie_t cookie) 4021 { 4022 mac_cb_t *mcb; 4023 mac_tx_notify_cb_t *mtnfp; 4024 4025 /* Wakeup callback registered clients */ 4026 MAC_CALLBACK_WALKER_INC(&mcip->mci_tx_notify_cb_info); 4027 for (mcb = mcip->mci_tx_notify_cb_list; mcb != NULL; 4028 mcb = mcb->mcb_nextp) { 4029 mtnfp = (mac_tx_notify_cb_t *)mcb->mcb_objp; 4030 mtnfp->mtnf_fn(mtnfp->mtnf_arg, cookie); 4031 } 4032 MAC_CALLBACK_WALKER_DCR(&mcip->mci_tx_notify_cb_info, 4033 &mcip->mci_tx_notify_cb_list); 4034 } 4035 4036 /* ARGSUSED */ 4037 void 4038 mac_tx_srs_drain(mac_soft_ring_set_t *mac_srs, uint_t proc_type) 4039 { 4040 mblk_t *head, *tail; 4041 size_t sz; 4042 uint32_t tx_mode; 4043 uint_t saved_pkt_count; 4044 mac_tx_stats_t stats; 4045 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 4046 clock_t now; 4047 4048 saved_pkt_count = 0; 4049 ASSERT(mutex_owned(&mac_srs->srs_lock)); 4050 ASSERT(!(mac_srs->srs_state & SRS_PROC)); 4051 4052 mac_srs->srs_state |= SRS_PROC; 4053 4054 tx_mode = srs_tx->st_mode; 4055 if (tx_mode == SRS_TX_DEFAULT || tx_mode == SRS_TX_SERIALIZE) { 4056 if (mac_srs->srs_first != NULL) { 4057 head = mac_srs->srs_first; 4058 tail = mac_srs->srs_last; 4059 saved_pkt_count = mac_srs->srs_count; 4060 mac_srs->srs_first = NULL; 4061 mac_srs->srs_last = NULL; 4062 mac_srs->srs_count = 0; 4063 mutex_exit(&mac_srs->srs_lock); 4064 4065 head = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 4066 head, &stats); 4067 4068 mutex_enter(&mac_srs->srs_lock); 4069 if (head != NULL) { 4070 /* Device out of tx desc, set block */ 4071 if (head->b_next == NULL) 4072 VERIFY(head == tail); 4073 tail->b_next = mac_srs->srs_first; 4074 mac_srs->srs_first = head; 4075 mac_srs->srs_count += 4076 (saved_pkt_count - stats.mts_opackets); 4077 if (mac_srs->srs_last == NULL) 4078 mac_srs->srs_last = tail; 4079 MAC_TX_SRS_BLOCK(mac_srs, head); 4080 } else { 4081 srs_tx->st_woken_up = B_FALSE; 4082 SRS_TX_STATS_UPDATE(mac_srs, &stats); 4083 } 4084 } 4085 } else if (tx_mode == SRS_TX_BW) { 4086 /* 4087 * We are here because the timer fired and we have some data 4088 * to tranmit. Also mac_tx_srs_worker should have reset 4089 * SRS_BW_ENFORCED flag 4090 */ 4091 ASSERT(!(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)); 4092 head = tail = mac_srs->srs_first; 4093 while (mac_srs->srs_first != NULL) { 4094 tail = mac_srs->srs_first; 4095 tail->b_prev = NULL; 4096 mac_srs->srs_first = tail->b_next; 4097 if (mac_srs->srs_first == NULL) 4098 mac_srs->srs_last = NULL; 4099 mac_srs->srs_count--; 4100 sz = msgdsize(tail); 4101 mac_srs->srs_size -= sz; 4102 saved_pkt_count++; 4103 MAC_TX_UPDATE_BW_INFO(mac_srs, sz); 4104 4105 if (mac_srs->srs_bw->mac_bw_used < 4106 mac_srs->srs_bw->mac_bw_limit) 4107 continue; 4108 4109 now = ddi_get_lbolt(); 4110 if (mac_srs->srs_bw->mac_bw_curr_time != now) { 4111 mac_srs->srs_bw->mac_bw_curr_time = now; 4112 mac_srs->srs_bw->mac_bw_used = sz; 4113 continue; 4114 } 4115 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED; 4116 break; 4117 } 4118 4119 ASSERT((head == NULL && tail == NULL) || 4120 (head != NULL && tail != NULL)); 4121 if (tail != NULL) { 4122 tail->b_next = NULL; 4123 mutex_exit(&mac_srs->srs_lock); 4124 4125 head = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2, 4126 head, &stats); 4127 4128 mutex_enter(&mac_srs->srs_lock); 4129 if (head != NULL) { 4130 uint_t size_sent; 4131 4132 /* Device out of tx desc, set block */ 4133 if (head->b_next == NULL) 4134 VERIFY(head == tail); 4135 tail->b_next = mac_srs->srs_first; 4136 mac_srs->srs_first = head; 4137 mac_srs->srs_count += 4138 (saved_pkt_count - stats.mts_opackets); 4139 if (mac_srs->srs_last == NULL) 4140 mac_srs->srs_last = tail; 4141 size_sent = sz - stats.mts_obytes; 4142 mac_srs->srs_size += size_sent; 4143 mac_srs->srs_bw->mac_bw_sz += size_sent; 4144 if (mac_srs->srs_bw->mac_bw_used > size_sent) { 4145 mac_srs->srs_bw->mac_bw_used -= 4146 size_sent; 4147 } else { 4148 mac_srs->srs_bw->mac_bw_used = 0; 4149 } 4150 MAC_TX_SRS_BLOCK(mac_srs, head); 4151 } else { 4152 srs_tx->st_woken_up = B_FALSE; 4153 SRS_TX_STATS_UPDATE(mac_srs, &stats); 4154 } 4155 } 4156 } else if (tx_mode == SRS_TX_BW_FANOUT || tx_mode == SRS_TX_BW_AGGR) { 4157 mblk_t *prev; 4158 uint64_t hint; 4159 4160 /* 4161 * We are here because the timer fired and we 4162 * have some quota to tranmit. 4163 */ 4164 prev = NULL; 4165 head = tail = mac_srs->srs_first; 4166 while (mac_srs->srs_first != NULL) { 4167 tail = mac_srs->srs_first; 4168 mac_srs->srs_first = tail->b_next; 4169 if (mac_srs->srs_first == NULL) 4170 mac_srs->srs_last = NULL; 4171 mac_srs->srs_count--; 4172 sz = msgdsize(tail); 4173 mac_srs->srs_size -= sz; 4174 mac_srs->srs_bw->mac_bw_used += sz; 4175 if (prev == NULL) 4176 hint = (ulong_t)tail->b_prev; 4177 if (hint != (ulong_t)tail->b_prev) { 4178 prev->b_next = NULL; 4179 mutex_exit(&mac_srs->srs_lock); 4180 TX_SRS_TO_SOFT_RING(mac_srs, head, hint); 4181 head = tail; 4182 hint = (ulong_t)tail->b_prev; 4183 mutex_enter(&mac_srs->srs_lock); 4184 } 4185 4186 prev = tail; 4187 tail->b_prev = NULL; 4188 if (mac_srs->srs_bw->mac_bw_used < 4189 mac_srs->srs_bw->mac_bw_limit) 4190 continue; 4191 4192 now = ddi_get_lbolt(); 4193 if (mac_srs->srs_bw->mac_bw_curr_time != now) { 4194 mac_srs->srs_bw->mac_bw_curr_time = now; 4195 mac_srs->srs_bw->mac_bw_used = 0; 4196 continue; 4197 } 4198 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED; 4199 break; 4200 } 4201 ASSERT((head == NULL && tail == NULL) || 4202 (head != NULL && tail != NULL)); 4203 if (tail != NULL) { 4204 tail->b_next = NULL; 4205 mutex_exit(&mac_srs->srs_lock); 4206 TX_SRS_TO_SOFT_RING(mac_srs, head, hint); 4207 mutex_enter(&mac_srs->srs_lock); 4208 } 4209 } 4210 /* 4211 * SRS_TX_FANOUT case not considered here because packets 4212 * won't be queued in the SRS for this case. Packets will 4213 * be sent directly to soft rings underneath and if there 4214 * is any queueing at all, it would be in Tx side soft 4215 * rings. 4216 */ 4217 4218 /* 4219 * When srs_count becomes 0, reset SRS_TX_HIWAT and 4220 * SRS_TX_WAKEUP_CLIENT and wakeup registered clients. 4221 */ 4222 if (mac_srs->srs_count == 0 && (mac_srs->srs_state & 4223 (SRS_TX_HIWAT | SRS_TX_WAKEUP_CLIENT | SRS_ENQUEUED))) { 4224 mac_client_impl_t *mcip = mac_srs->srs_mcip; 4225 boolean_t wakeup_required = B_FALSE; 4226 4227 if (mac_srs->srs_state & 4228 (SRS_TX_HIWAT|SRS_TX_WAKEUP_CLIENT)) { 4229 wakeup_required = B_TRUE; 4230 } 4231 mac_srs->srs_state &= ~(SRS_TX_HIWAT | 4232 SRS_TX_WAKEUP_CLIENT | SRS_ENQUEUED); 4233 mutex_exit(&mac_srs->srs_lock); 4234 if (wakeup_required) { 4235 mac_tx_invoke_callbacks(mcip, (mac_tx_cookie_t)mac_srs); 4236 /* 4237 * If the client is not the primary MAC client, then we 4238 * need to send the notification to the clients upper 4239 * MAC, i.e. mci_upper_mip. 4240 */ 4241 mac_tx_notify(mcip->mci_upper_mip != NULL ? 4242 mcip->mci_upper_mip : mcip->mci_mip); 4243 } 4244 mutex_enter(&mac_srs->srs_lock); 4245 } 4246 mac_srs->srs_state &= ~SRS_PROC; 4247 } 4248 4249 /* 4250 * Given a packet, get the flow_entry that identifies the flow 4251 * to which that packet belongs. The flow_entry will contain 4252 * the transmit function to be used to send the packet. If the 4253 * function returns NULL, the packet should be sent using the 4254 * underlying NIC. 4255 */ 4256 static flow_entry_t * 4257 mac_tx_classify(mac_impl_t *mip, mblk_t *mp) 4258 { 4259 flow_entry_t *flent = NULL; 4260 mac_client_impl_t *mcip; 4261 int err; 4262 4263 /* 4264 * Do classification on the packet. 4265 */ 4266 err = mac_flow_lookup(mip->mi_flow_tab, mp, FLOW_OUTBOUND, &flent); 4267 if (err != 0) 4268 return (NULL); 4269 4270 /* 4271 * This flent might just be an additional one on the MAC client, 4272 * i.e. for classification purposes (different fdesc), however 4273 * the resources, SRS et. al., are in the mci_flent, so if 4274 * this isn't the mci_flent, we need to get it. 4275 */ 4276 if ((mcip = flent->fe_mcip) != NULL && mcip->mci_flent != flent) { 4277 FLOW_REFRELE(flent); 4278 flent = mcip->mci_flent; 4279 FLOW_TRY_REFHOLD(flent, err); 4280 if (err != 0) 4281 return (NULL); 4282 } 4283 4284 return (flent); 4285 } 4286 4287 /* 4288 * This macro is only meant to be used by mac_tx_send(). 4289 */ 4290 #define CHECK_VID_AND_ADD_TAG(mp) { \ 4291 if (vid_check) { \ 4292 int err = 0; \ 4293 \ 4294 MAC_VID_CHECK(src_mcip, (mp), err); \ 4295 if (err != 0) { \ 4296 freemsg((mp)); \ 4297 (mp) = next; \ 4298 oerrors++; \ 4299 continue; \ 4300 } \ 4301 } \ 4302 if (add_tag) { \ 4303 (mp) = mac_add_vlan_tag((mp), 0, vid); \ 4304 if ((mp) == NULL) { \ 4305 (mp) = next; \ 4306 oerrors++; \ 4307 continue; \ 4308 } \ 4309 } \ 4310 } 4311 4312 mblk_t * 4313 mac_tx_send(mac_client_handle_t mch, mac_ring_handle_t ring, mblk_t *mp_chain, 4314 mac_tx_stats_t *stats) 4315 { 4316 mac_client_impl_t *src_mcip = (mac_client_impl_t *)mch; 4317 mac_impl_t *mip = src_mcip->mci_mip; 4318 uint_t obytes = 0, opackets = 0, oerrors = 0; 4319 mblk_t *mp = NULL, *next; 4320 boolean_t vid_check, add_tag; 4321 uint16_t vid = 0; 4322 4323 if (mip->mi_nclients > 1) { 4324 vid_check = MAC_VID_CHECK_NEEDED(src_mcip); 4325 add_tag = MAC_TAG_NEEDED(src_mcip); 4326 if (add_tag) 4327 vid = mac_client_vid(mch); 4328 } else { 4329 ASSERT(mip->mi_nclients == 1); 4330 vid_check = add_tag = B_FALSE; 4331 } 4332 4333 /* 4334 * Fastpath: if there's only one client, we simply send 4335 * the packet down to the underlying NIC. 4336 */ 4337 if (mip->mi_nactiveclients == 1) { 4338 DTRACE_PROBE2(fastpath, 4339 mac_client_impl_t *, src_mcip, mblk_t *, mp_chain); 4340 4341 mp = mp_chain; 4342 while (mp != NULL) { 4343 next = mp->b_next; 4344 mp->b_next = NULL; 4345 opackets++; 4346 obytes += (mp->b_cont == NULL ? MBLKL(mp) : 4347 msgdsize(mp)); 4348 4349 CHECK_VID_AND_ADD_TAG(mp); 4350 mp = mac_provider_tx(mip, ring, mp, src_mcip); 4351 4352 /* 4353 * If the driver is out of descriptors and does a 4354 * partial send it will return a chain of unsent 4355 * mblks. Adjust the accounting stats. 4356 */ 4357 if (mp != NULL) { 4358 opackets--; 4359 obytes -= msgdsize(mp); 4360 mp->b_next = next; 4361 break; 4362 } 4363 mp = next; 4364 } 4365 goto done; 4366 } 4367 4368 /* 4369 * No fastpath, we either have more than one MAC client 4370 * defined on top of the same MAC, or one or more MAC 4371 * client promiscuous callbacks. 4372 */ 4373 DTRACE_PROBE3(slowpath, mac_client_impl_t *, 4374 src_mcip, int, mip->mi_nclients, mblk_t *, mp_chain); 4375 4376 mp = mp_chain; 4377 while (mp != NULL) { 4378 flow_entry_t *dst_flow_ent; 4379 void *flow_cookie; 4380 size_t pkt_size; 4381 4382 next = mp->b_next; 4383 mp->b_next = NULL; 4384 opackets++; 4385 pkt_size = (mp->b_cont == NULL ? MBLKL(mp) : msgdsize(mp)); 4386 obytes += pkt_size; 4387 CHECK_VID_AND_ADD_TAG(mp); 4388 4389 /* 4390 * Find the destination. 4391 */ 4392 dst_flow_ent = mac_tx_classify(mip, mp); 4393 4394 if (dst_flow_ent != NULL) { 4395 /* 4396 * Got a matching flow. It's either another 4397 * MAC client, or a broadcast/multicast flow. 4398 */ 4399 flow_cookie = mac_flow_get_client_cookie(dst_flow_ent); 4400 4401 if (flow_cookie != NULL) { 4402 /* 4403 * The vnic_bcast_send function expects 4404 * to receive the sender MAC client 4405 * as value for arg2. 4406 */ 4407 mac_bcast_send(flow_cookie, src_mcip, mp, 4408 B_TRUE); 4409 } else { 4410 /* 4411 * loopback the packet to a local MAC 4412 * client. We force a context switch 4413 * if both source and destination MAC 4414 * clients are used by IP, i.e. 4415 * bypass is set. 4416 */ 4417 boolean_t do_switch; 4418 4419 mac_client_impl_t *dst_mcip = 4420 dst_flow_ent->fe_mcip; 4421 4422 /* 4423 * Check if there are promiscuous mode 4424 * callbacks defined. This check is 4425 * done here in the 'else' case and 4426 * not in other cases because this 4427 * path is for local loopback 4428 * communication which does not go 4429 * through MAC_TX(). For paths that go 4430 * through MAC_TX(), the promisc_list 4431 * check is done inside the MAC_TX() 4432 * macro. 4433 */ 4434 if (mip->mi_promisc_list != NULL) { 4435 mac_promisc_dispatch(mip, mp, src_mcip, 4436 B_TRUE); 4437 } 4438 4439 do_switch = ((src_mcip->mci_state_flags & 4440 dst_mcip->mci_state_flags & 4441 MCIS_CLIENT_POLL_CAPABLE) != 0); 4442 4443 mac_hw_emul(&mp, NULL, NULL, MAC_ALL_EMULS); 4444 if (mp != NULL) { 4445 (dst_flow_ent->fe_cb_fn)( 4446 dst_flow_ent->fe_cb_arg1, 4447 dst_flow_ent->fe_cb_arg2, 4448 mp, do_switch); 4449 } 4450 4451 } 4452 FLOW_REFRELE(dst_flow_ent); 4453 } else { 4454 /* 4455 * Unknown destination, send via the underlying 4456 * NIC. 4457 */ 4458 mp = mac_provider_tx(mip, ring, mp, src_mcip); 4459 if (mp != NULL) { 4460 /* 4461 * Adjust for the last packet that 4462 * could not be transmitted 4463 */ 4464 opackets--; 4465 obytes -= pkt_size; 4466 mp->b_next = next; 4467 break; 4468 } 4469 } 4470 mp = next; 4471 } 4472 4473 done: 4474 stats->mts_obytes = obytes; 4475 stats->mts_opackets = opackets; 4476 stats->mts_oerrors = oerrors; 4477 return (mp); 4478 } 4479 4480 /* 4481 * mac_tx_srs_ring_present 4482 * 4483 * Returns whether the specified ring is part of the specified SRS. 4484 */ 4485 boolean_t 4486 mac_tx_srs_ring_present(mac_soft_ring_set_t *srs, mac_ring_t *tx_ring) 4487 { 4488 int i; 4489 mac_soft_ring_t *soft_ring; 4490 4491 if (srs->srs_tx.st_arg2 == tx_ring) 4492 return (B_TRUE); 4493 4494 for (i = 0; i < srs->srs_tx_ring_count; i++) { 4495 soft_ring = srs->srs_tx_soft_rings[i]; 4496 if (soft_ring->s_ring_tx_arg2 == tx_ring) 4497 return (B_TRUE); 4498 } 4499 4500 return (B_FALSE); 4501 } 4502 4503 /* 4504 * mac_tx_srs_get_soft_ring 4505 * 4506 * Returns the TX soft ring associated with the given ring, if present. 4507 */ 4508 mac_soft_ring_t * 4509 mac_tx_srs_get_soft_ring(mac_soft_ring_set_t *srs, mac_ring_t *tx_ring) 4510 { 4511 int i; 4512 mac_soft_ring_t *soft_ring; 4513 4514 if (srs->srs_tx.st_arg2 == tx_ring) 4515 return (NULL); 4516 4517 for (i = 0; i < srs->srs_tx_ring_count; i++) { 4518 soft_ring = srs->srs_tx_soft_rings[i]; 4519 if (soft_ring->s_ring_tx_arg2 == tx_ring) 4520 return (soft_ring); 4521 } 4522 4523 return (NULL); 4524 } 4525 4526 /* 4527 * mac_tx_srs_wakeup 4528 * 4529 * Called when Tx desc become available. Wakeup the appropriate worker 4530 * thread after resetting the SRS_TX_BLOCKED/S_RING_BLOCK bit in the 4531 * state field. 4532 */ 4533 void 4534 mac_tx_srs_wakeup(mac_soft_ring_set_t *mac_srs, mac_ring_handle_t ring) 4535 { 4536 int i; 4537 mac_soft_ring_t *sringp; 4538 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx; 4539 4540 mutex_enter(&mac_srs->srs_lock); 4541 /* 4542 * srs_tx_ring_count == 0 is the single ring mode case. In 4543 * this mode, there will not be Tx soft rings associated 4544 * with the SRS. 4545 */ 4546 if (!MAC_TX_SOFT_RINGS(mac_srs)) { 4547 if (srs_tx->st_arg2 == ring && 4548 mac_srs->srs_state & SRS_TX_BLOCKED) { 4549 mac_srs->srs_state &= ~SRS_TX_BLOCKED; 4550 srs_tx->st_stat.mts_unblockcnt++; 4551 cv_signal(&mac_srs->srs_async); 4552 } 4553 /* 4554 * A wakeup can come before tx_srs_drain() could 4555 * grab srs lock and set SRS_TX_BLOCKED. So 4556 * always set woken_up flag when we come here. 4557 */ 4558 srs_tx->st_woken_up = B_TRUE; 4559 mutex_exit(&mac_srs->srs_lock); 4560 return; 4561 } 4562 4563 /* 4564 * If you are here, it is for FANOUT, BW_FANOUT, 4565 * AGGR_MODE or AGGR_BW_MODE case 4566 */ 4567 for (i = 0; i < mac_srs->srs_tx_ring_count; i++) { 4568 sringp = mac_srs->srs_tx_soft_rings[i]; 4569 mutex_enter(&sringp->s_ring_lock); 4570 if (sringp->s_ring_tx_arg2 == ring) { 4571 if (sringp->s_ring_state & S_RING_BLOCK) { 4572 sringp->s_ring_state &= ~S_RING_BLOCK; 4573 sringp->s_st_stat.mts_unblockcnt++; 4574 cv_signal(&sringp->s_ring_async); 4575 } 4576 sringp->s_ring_tx_woken_up = B_TRUE; 4577 } 4578 mutex_exit(&sringp->s_ring_lock); 4579 } 4580 mutex_exit(&mac_srs->srs_lock); 4581 } 4582 4583 /* 4584 * Once the driver is done draining, send a MAC_NOTE_TX notification to unleash 4585 * the blocked clients again. 4586 */ 4587 void 4588 mac_tx_notify(mac_impl_t *mip) 4589 { 4590 i_mac_notify(mip, MAC_NOTE_TX); 4591 } 4592 4593 /* 4594 * RX SOFTRING RELATED FUNCTIONS 4595 * 4596 * These functions really belong in mac_soft_ring.c and here for 4597 * a short period. 4598 */ 4599 4600 #define SOFT_RING_ENQUEUE_CHAIN(ringp, mp, tail, cnt, sz) { \ 4601 /* \ 4602 * Enqueue our mblk chain. \ 4603 */ \ 4604 ASSERT(MUTEX_HELD(&(ringp)->s_ring_lock)); \ 4605 \ 4606 if ((ringp)->s_ring_last != NULL) \ 4607 (ringp)->s_ring_last->b_next = (mp); \ 4608 else \ 4609 (ringp)->s_ring_first = (mp); \ 4610 (ringp)->s_ring_last = (tail); \ 4611 (ringp)->s_ring_count += (cnt); \ 4612 ASSERT((ringp)->s_ring_count > 0); \ 4613 if ((ringp)->s_ring_type & ST_RING_BW_CTL) { \ 4614 (ringp)->s_ring_size += sz; \ 4615 } \ 4616 } 4617 4618 /* 4619 * Default entry point to deliver a packet chain to a MAC client. 4620 * If the MAC client has flows, do the classification with these 4621 * flows as well. 4622 */ 4623 /* ARGSUSED */ 4624 void 4625 mac_rx_deliver(void *arg1, mac_resource_handle_t mrh, mblk_t *mp_chain, 4626 mac_header_info_t *arg3) 4627 { 4628 mac_client_impl_t *mcip = arg1; 4629 4630 if (mcip->mci_nvids == 1 && 4631 !(mcip->mci_state_flags & MCIS_STRIP_DISABLE)) { 4632 /* 4633 * If the client has exactly one VID associated with it 4634 * and striping of VLAN header is not disabled, 4635 * remove the VLAN tag from the packet before 4636 * passing it on to the client's receive callback. 4637 * Note that this needs to be done after we dispatch 4638 * the packet to the promiscuous listeners of the 4639 * client, since they expect to see the whole 4640 * frame including the VLAN headers. 4641 * 4642 * The MCIS_STRIP_DISABLE is only issued when sun4v 4643 * vsw is in play. 4644 */ 4645 mp_chain = mac_strip_vlan_tag_chain(mp_chain); 4646 } 4647 4648 mcip->mci_rx_fn(mcip->mci_rx_arg, mrh, mp_chain, B_FALSE); 4649 } 4650 4651 /* 4652 * Process a chain for a given soft ring. If the number of packets 4653 * queued in the SRS and its associated soft rings (including this 4654 * one) is very small (tracked by srs_poll_pkt_cnt) then allow the 4655 * entering thread (interrupt or poll thread) to process the chain 4656 * inline. This is meant to reduce latency under low load. 4657 * 4658 * The proc and arg for each mblk is already stored in the mblk in 4659 * appropriate places. 4660 */ 4661 /* ARGSUSED */ 4662 void 4663 mac_rx_soft_ring_process(mac_client_impl_t *mcip, mac_soft_ring_t *ringp, 4664 mblk_t *mp_chain, mblk_t *tail, int cnt, size_t sz) 4665 { 4666 mac_direct_rx_t proc; 4667 void *arg1; 4668 mac_resource_handle_t arg2; 4669 mac_soft_ring_set_t *mac_srs = ringp->s_ring_set; 4670 4671 ASSERT(ringp != NULL); 4672 ASSERT(mp_chain != NULL); 4673 ASSERT(tail != NULL); 4674 ASSERT(MUTEX_NOT_HELD(&ringp->s_ring_lock)); 4675 4676 mutex_enter(&ringp->s_ring_lock); 4677 ringp->s_ring_total_inpkt += cnt; 4678 ringp->s_ring_total_rbytes += sz; 4679 if ((mac_srs->srs_rx.sr_poll_pkt_cnt <= 1) && 4680 !(ringp->s_ring_type & ST_RING_WORKER_ONLY)) { 4681 /* If on processor or blanking on, then enqueue and return */ 4682 if (ringp->s_ring_state & S_RING_BLANK || 4683 ringp->s_ring_state & S_RING_PROC) { 4684 SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz); 4685 mutex_exit(&ringp->s_ring_lock); 4686 return; 4687 } 4688 proc = ringp->s_ring_rx_func; 4689 arg1 = ringp->s_ring_rx_arg1; 4690 arg2 = ringp->s_ring_rx_arg2; 4691 /* 4692 * See if anything is already queued. If we are the 4693 * first packet, do inline processing else queue the 4694 * packet and do the drain. 4695 */ 4696 if (ringp->s_ring_first == NULL) { 4697 /* 4698 * Fast-path, ok to process and nothing queued. 4699 */ 4700 ringp->s_ring_run = curthread; 4701 ringp->s_ring_state |= (S_RING_PROC); 4702 4703 mutex_exit(&ringp->s_ring_lock); 4704 4705 /* 4706 * We are the chain of 1 packet so 4707 * go through this fast path. 4708 */ 4709 ASSERT(mp_chain->b_next == NULL); 4710 4711 (*proc)(arg1, arg2, mp_chain, NULL); 4712 4713 ASSERT(MUTEX_NOT_HELD(&ringp->s_ring_lock)); 4714 /* 4715 * If we have an SRS performing bandwidth 4716 * control then we need to decrement the size 4717 * and count so the SRS has an accurate count 4718 * of the data queued between the SRS and its 4719 * soft rings. We decrement the counters only 4720 * when the packet is processed by both the 4721 * SRS and the soft ring. 4722 */ 4723 mutex_enter(&mac_srs->srs_lock); 4724 MAC_UPDATE_SRS_COUNT_LOCKED(mac_srs, cnt); 4725 MAC_UPDATE_SRS_SIZE_LOCKED(mac_srs, sz); 4726 mutex_exit(&mac_srs->srs_lock); 4727 4728 mutex_enter(&ringp->s_ring_lock); 4729 ringp->s_ring_run = NULL; 4730 ringp->s_ring_state &= ~S_RING_PROC; 4731 if (ringp->s_ring_state & S_RING_CLIENT_WAIT) 4732 cv_signal(&ringp->s_ring_client_cv); 4733 4734 if ((ringp->s_ring_first == NULL) || 4735 (ringp->s_ring_state & S_RING_BLANK)) { 4736 /* 4737 * We processed a single packet inline 4738 * and nothing new has arrived or our 4739 * receiver doesn't want to receive 4740 * any packets. We are done. 4741 */ 4742 mutex_exit(&ringp->s_ring_lock); 4743 return; 4744 } 4745 } else { 4746 SOFT_RING_ENQUEUE_CHAIN(ringp, 4747 mp_chain, tail, cnt, sz); 4748 } 4749 4750 /* 4751 * We are here because either we couldn't do inline 4752 * processing (because something was already 4753 * queued), or we had a chain of more than one 4754 * packet, or something else arrived after we were 4755 * done with inline processing. 4756 */ 4757 ASSERT(MUTEX_HELD(&ringp->s_ring_lock)); 4758 ASSERT(ringp->s_ring_first != NULL); 4759 4760 ringp->s_ring_drain_func(ringp); 4761 mutex_exit(&ringp->s_ring_lock); 4762 return; 4763 } else { 4764 /* ST_RING_WORKER_ONLY case */ 4765 SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz); 4766 mac_soft_ring_worker_wakeup(ringp); 4767 mutex_exit(&ringp->s_ring_lock); 4768 } 4769 } 4770 4771 /* 4772 * TX SOFTRING RELATED FUNCTIONS 4773 * 4774 * These functions really belong in mac_soft_ring.c and here for 4775 * a short period. 4776 */ 4777 4778 #define TX_SOFT_RING_ENQUEUE_CHAIN(ringp, mp, tail, cnt, sz) { \ 4779 ASSERT(MUTEX_HELD(&ringp->s_ring_lock)); \ 4780 ringp->s_ring_state |= S_RING_ENQUEUED; \ 4781 SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz); \ 4782 } 4783 4784 /* 4785 * mac_tx_sring_queued 4786 * 4787 * When we are out of transmit descriptors and we already have a 4788 * queue that exceeds hiwat (or the client called us with 4789 * MAC_TX_NO_ENQUEUE or MAC_DROP_ON_NO_DESC flag), return the 4790 * soft ring pointer as the opaque cookie for the client enable 4791 * flow control. 4792 */ 4793 static mac_tx_cookie_t 4794 mac_tx_sring_enqueue(mac_soft_ring_t *ringp, mblk_t *mp_chain, uint16_t flag, 4795 mblk_t **ret_mp) 4796 { 4797 int cnt; 4798 size_t sz; 4799 mblk_t *tail; 4800 mac_soft_ring_set_t *mac_srs = ringp->s_ring_set; 4801 mac_tx_cookie_t cookie = 0; 4802 boolean_t wakeup_worker = B_TRUE; 4803 4804 ASSERT(MUTEX_HELD(&ringp->s_ring_lock)); 4805 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 4806 if (flag & MAC_DROP_ON_NO_DESC) { 4807 mac_drop_chain(mp_chain, "Tx softring no desc"); 4808 /* increment freed stats */ 4809 ringp->s_ring_drops += cnt; 4810 cookie = (mac_tx_cookie_t)ringp; 4811 } else { 4812 if (ringp->s_ring_first != NULL) 4813 wakeup_worker = B_FALSE; 4814 4815 if (flag & MAC_TX_NO_ENQUEUE) { 4816 /* 4817 * If QUEUED is not set, queue the packet 4818 * and let mac_tx_soft_ring_drain() set 4819 * the TX_BLOCKED bit for the reasons 4820 * explained above. Otherwise, return the 4821 * mblks. 4822 */ 4823 if (wakeup_worker) { 4824 TX_SOFT_RING_ENQUEUE_CHAIN(ringp, 4825 mp_chain, tail, cnt, sz); 4826 } else { 4827 ringp->s_ring_state |= S_RING_WAKEUP_CLIENT; 4828 cookie = (mac_tx_cookie_t)ringp; 4829 *ret_mp = mp_chain; 4830 } 4831 } else { 4832 boolean_t enqueue = B_TRUE; 4833 4834 if (ringp->s_ring_count > ringp->s_ring_tx_hiwat) { 4835 /* 4836 * flow-controlled. Store ringp in cookie 4837 * so that it can be returned as 4838 * mac_tx_cookie_t to client 4839 */ 4840 ringp->s_ring_state |= S_RING_TX_HIWAT; 4841 cookie = (mac_tx_cookie_t)ringp; 4842 ringp->s_ring_hiwat_cnt++; 4843 if (ringp->s_ring_count > 4844 ringp->s_ring_tx_max_q_cnt) { 4845 /* increment freed stats */ 4846 ringp->s_ring_drops += cnt; 4847 /* 4848 * b_prev may be set to the fanout hint 4849 * hence can't use freemsg directly 4850 */ 4851 mac_drop_chain(mp_chain, 4852 "Tx softring max queue"); 4853 DTRACE_PROBE1(tx_queued_hiwat, 4854 mac_soft_ring_t *, ringp); 4855 enqueue = B_FALSE; 4856 } 4857 } 4858 if (enqueue) { 4859 TX_SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, 4860 tail, cnt, sz); 4861 } 4862 } 4863 if (wakeup_worker) 4864 cv_signal(&ringp->s_ring_async); 4865 } 4866 return (cookie); 4867 } 4868 4869 4870 /* 4871 * mac_tx_soft_ring_process 4872 * 4873 * This routine is called when fanning out outgoing traffic among 4874 * multipe Tx rings. 4875 * Note that a soft ring is associated with a h/w Tx ring. 4876 */ 4877 mac_tx_cookie_t 4878 mac_tx_soft_ring_process(mac_soft_ring_t *ringp, mblk_t *mp_chain, 4879 uint16_t flag, mblk_t **ret_mp) 4880 { 4881 mac_soft_ring_set_t *mac_srs = ringp->s_ring_set; 4882 int cnt; 4883 size_t sz; 4884 mblk_t *tail; 4885 mac_tx_cookie_t cookie = 0; 4886 4887 ASSERT(ringp != NULL); 4888 ASSERT(mp_chain != NULL); 4889 ASSERT(MUTEX_NOT_HELD(&ringp->s_ring_lock)); 4890 /* 4891 * The following modes can come here: SRS_TX_BW_FANOUT, 4892 * SRS_TX_FANOUT, SRS_TX_AGGR, SRS_TX_BW_AGGR. 4893 */ 4894 ASSERT(MAC_TX_SOFT_RINGS(mac_srs)); 4895 ASSERT(mac_srs->srs_tx.st_mode == SRS_TX_FANOUT || 4896 mac_srs->srs_tx.st_mode == SRS_TX_BW_FANOUT || 4897 mac_srs->srs_tx.st_mode == SRS_TX_AGGR || 4898 mac_srs->srs_tx.st_mode == SRS_TX_BW_AGGR); 4899 4900 if (ringp->s_ring_type & ST_RING_WORKER_ONLY) { 4901 /* Serialization mode */ 4902 4903 mutex_enter(&ringp->s_ring_lock); 4904 if (ringp->s_ring_count > ringp->s_ring_tx_hiwat) { 4905 cookie = mac_tx_sring_enqueue(ringp, mp_chain, 4906 flag, ret_mp); 4907 mutex_exit(&ringp->s_ring_lock); 4908 return (cookie); 4909 } 4910 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz); 4911 TX_SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz); 4912 if (ringp->s_ring_state & (S_RING_BLOCK | S_RING_PROC)) { 4913 /* 4914 * If ring is blocked due to lack of Tx 4915 * descs, just return. Worker thread 4916 * will get scheduled when Tx desc's 4917 * become available. 4918 */ 4919 mutex_exit(&ringp->s_ring_lock); 4920 return (cookie); 4921 } 4922 mac_soft_ring_worker_wakeup(ringp); 4923 mutex_exit(&ringp->s_ring_lock); 4924 return (cookie); 4925 } else { 4926 /* Default fanout mode */ 4927 /* 4928 * S_RING_BLOCKED is set when underlying NIC runs 4929 * out of Tx descs and messages start getting 4930 * queued. It won't get reset until 4931 * tx_srs_drain() completely drains out the 4932 * messages. 4933 */ 4934 mac_tx_stats_t stats; 4935 4936 if (ringp->s_ring_state & S_RING_ENQUEUED) { 4937 /* Tx descs/resources not available */ 4938 mutex_enter(&ringp->s_ring_lock); 4939 if (ringp->s_ring_state & S_RING_ENQUEUED) { 4940 cookie = mac_tx_sring_enqueue(ringp, mp_chain, 4941 flag, ret_mp); 4942 mutex_exit(&ringp->s_ring_lock); 4943 return (cookie); 4944 } 4945 /* 4946 * While we were computing mblk count, the 4947 * flow control condition got relieved. 4948 * Continue with the transmission. 4949 */ 4950 mutex_exit(&ringp->s_ring_lock); 4951 } 4952 4953 mp_chain = mac_tx_send(ringp->s_ring_tx_arg1, 4954 ringp->s_ring_tx_arg2, mp_chain, &stats); 4955 4956 /* 4957 * Multiple threads could be here sending packets. 4958 * Under such conditions, it is not possible to 4959 * automically set S_RING_BLOCKED bit to indicate 4960 * out of tx desc condition. To atomically set 4961 * this, we queue the returned packet and do 4962 * the setting of S_RING_BLOCKED in 4963 * mac_tx_soft_ring_drain(). 4964 */ 4965 if (mp_chain != NULL) { 4966 mutex_enter(&ringp->s_ring_lock); 4967 cookie = 4968 mac_tx_sring_enqueue(ringp, mp_chain, flag, ret_mp); 4969 mutex_exit(&ringp->s_ring_lock); 4970 return (cookie); 4971 } 4972 SRS_TX_STATS_UPDATE(mac_srs, &stats); 4973 SOFTRING_TX_STATS_UPDATE(ringp, &stats); 4974 4975 return (0); 4976 } 4977 } 4978