1 /*- 2 * Copyright (c) 2001-2002 Luigi Rizzo 3 * 4 * Supported by: the Xorp Project (www.xorp.org) 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD: src/sys/kern/kern_poll.c,v 1.2.2.4 2002/06/27 23:26:33 luigi Exp $ 28 */ 29 30 #include "opt_ifpoll.h" 31 32 #include <sys/param.h> 33 #include <sys/kernel.h> 34 #include <sys/ktr.h> 35 #include <sys/malloc.h> 36 #include <sys/serialize.h> 37 #include <sys/socket.h> 38 #include <sys/sysctl.h> 39 40 #include <sys/thread2.h> 41 #include <sys/msgport2.h> 42 43 #include <machine/atomic.h> 44 #include <machine/clock.h> 45 #include <machine/smp.h> 46 47 #include <net/if.h> 48 #include <net/if_poll.h> 49 #include <net/netmsg2.h> 50 51 /* 52 * Polling support for network device drivers. 53 * 54 * Drivers which support this feature try to register one status polling 55 * handler and several TX/RX polling handlers with the polling code. 56 * If interface's if_qpoll is called with non-NULL second argument, then 57 * a register operation is requested, else a deregister operation is 58 * requested. If the requested operation is "register", driver should 59 * setup the ifpoll_info passed in accoding its own needs: 60 * ifpoll_info.ifpi_status.status_func == NULL 61 * No status polling handler will be installed on CPU(0) 62 * ifpoll_info.ifpi_rx[n].poll_func == NULL 63 * No RX polling handler will be installed on CPU(n) 64 * ifpoll_info.ifpi_tx[n].poll_func == NULL 65 * No TX polling handler will be installed on CPU(n) 66 * 67 * RX is polled at the specified polling frequency (net.ifpoll.X.pollhz). 68 * TX and status polling could be done at lower frequency than RX frequency 69 * (net.ifpoll.0.status_frac and net.ifpoll.X.tx_frac). To avoid systimer 70 * staggering at high frequency, RX systimer gives TX and status polling a 71 * piggyback (XXX). 72 * 73 * All of the registered polling handlers are called only if the interface 74 * is marked as 'IFF_RUNNING and IFF_NPOLLING'. However, the interface's 75 * register and deregister function (ifnet.if_qpoll) will be called even 76 * if interface is not marked with 'IFF_RUNNING'. 77 * 78 * If registration is successful, the driver must disable interrupts, 79 * and further I/O is performed through the TX/RX polling handler, which 80 * are invoked (at least once per clock tick) with 3 arguments: the "arg" 81 * passed at register time, a struct ifnet pointer, and a "count" limit. 82 * The registered serializer will be held before calling the related 83 * polling handler. 84 * 85 * The count limit specifies how much work the handler can do during the 86 * call -- typically this is the number of packets to be received, or 87 * transmitted, etc. (drivers are free to interpret this number, as long 88 * as the max time spent in the function grows roughly linearly with the 89 * count). 90 * 91 * A second variable controls the sharing of CPU between polling/kernel 92 * network processing, and other activities (typically userlevel tasks): 93 * net.ifpoll.X.{rx,tx}.user_frac (between 0 and 100, default 50) sets the 94 * share of CPU allocated to user tasks. CPU is allocated proportionally 95 * to the shares, by dynamically adjusting the "count" (poll_burst). 96 * 97 * Other parameters can should be left to their default values. 98 * The following constraints hold 99 * 100 * 1 <= poll_burst <= poll_burst_max 101 * 1 <= poll_each_burst <= poll_burst_max 102 * MIN_POLL_BURST_MAX <= poll_burst_max <= MAX_POLL_BURST_MAX 103 */ 104 105 #define IFPOLL_LIST_LEN 128 106 #define IFPOLL_FREQ_MAX 30000 107 108 #define MIN_IOPOLL_BURST_MAX 10 109 #define MAX_IOPOLL_BURST_MAX 1000 110 #define IOPOLL_BURST_MAX 150 /* good for 100Mbit net and HZ=1000 */ 111 112 #define IOPOLL_EACH_BURST 5 113 114 #define IFPOLL_FREQ_DEFAULT 2000 115 116 #define IFPOLL_TXFRAC_DEFAULT 1 /* 1/2 of the pollhz */ 117 #define IFPOLL_STFRAC_DEFAULT 19 /* 1/20 of the pollhz */ 118 119 #define IFPOLL_RX 0x1 120 #define IFPOLL_TX 0x2 121 122 union ifpoll_time { 123 struct timeval tv; 124 uint64_t tsc; 125 }; 126 127 struct iopoll_rec { 128 struct lwkt_serialize *serializer; 129 struct ifnet *ifp; 130 void *arg; 131 ifpoll_iofn_t poll_func; 132 }; 133 134 struct iopoll_ctx { 135 union ifpoll_time prev_t; 136 uint32_t short_ticks; /* statistics */ 137 uint32_t lost_polls; /* statistics */ 138 uint32_t suspect; /* statistics */ 139 uint32_t stalled; /* statistics */ 140 uint32_t pending_polls; /* state */ 141 142 struct netmsg poll_netmsg; 143 144 int poll_cpuid; 145 int pollhz; 146 uint32_t phase; /* state */ 147 int residual_burst; /* state */ 148 uint32_t poll_each_burst; /* tunable */ 149 union ifpoll_time poll_start_t; /* state */ 150 151 uint32_t poll_handlers; /* next free entry in pr[]. */ 152 struct iopoll_rec pr[IFPOLL_LIST_LEN]; 153 154 struct netmsg poll_more_netmsg; 155 156 uint32_t poll_burst; /* state */ 157 uint32_t poll_burst_max; /* tunable */ 158 uint32_t user_frac; /* tunable */ 159 uint32_t kern_frac; /* state */ 160 161 struct sysctl_ctx_list poll_sysctl_ctx; 162 struct sysctl_oid *poll_sysctl_tree; 163 } __cachealign; 164 165 struct poll_comm { 166 struct systimer pollclock; 167 int poll_cpuid; 168 169 int stfrac_count; /* state */ 170 int poll_stfrac; /* tunable */ 171 172 int txfrac_count; /* state */ 173 int poll_txfrac; /* tunable */ 174 175 int pollhz; /* tunable */ 176 177 struct sysctl_ctx_list sysctl_ctx; 178 struct sysctl_oid *sysctl_tree; 179 } __cachealign; 180 181 struct stpoll_rec { 182 struct lwkt_serialize *serializer; 183 struct ifnet *ifp; 184 ifpoll_stfn_t status_func; 185 }; 186 187 struct stpoll_ctx { 188 struct netmsg poll_netmsg; 189 190 int pollhz; 191 192 uint32_t poll_handlers; /* next free entry in pr[]. */ 193 struct stpoll_rec pr[IFPOLL_LIST_LEN]; 194 195 struct sysctl_ctx_list poll_sysctl_ctx; 196 struct sysctl_oid *poll_sysctl_tree; 197 }; 198 199 struct iopoll_sysctl_netmsg { 200 struct netmsg nmsg; 201 struct iopoll_ctx *ctx; 202 }; 203 204 void ifpoll_init_pcpu(int); 205 static void ifpoll_register_handler(struct netmsg *); 206 static void ifpoll_deregister_handler(struct netmsg *); 207 208 /* 209 * Status polling 210 */ 211 static void stpoll_init(void); 212 static void stpoll_handler(struct netmsg *); 213 static void stpoll_clock(struct stpoll_ctx *); 214 static int stpoll_register(struct ifnet *, const struct ifpoll_status *); 215 static int stpoll_deregister(struct ifnet *); 216 217 /* 218 * RX/TX polling 219 */ 220 static struct iopoll_ctx *iopoll_ctx_create(int, int); 221 static void iopoll_init(int); 222 static void iopoll_handler(struct netmsg *); 223 static void iopollmore_handler(struct netmsg *); 224 static void iopoll_clock(struct iopoll_ctx *); 225 static int iopoll_register(struct ifnet *, struct iopoll_ctx *, 226 const struct ifpoll_io *); 227 static int iopoll_deregister(struct ifnet *, struct iopoll_ctx *); 228 229 static void iopoll_add_sysctl(struct sysctl_ctx_list *, 230 struct sysctl_oid_list *, struct iopoll_ctx *); 231 static void sysctl_burstmax_handler(struct netmsg *); 232 static int sysctl_burstmax(SYSCTL_HANDLER_ARGS); 233 static void sysctl_eachburst_handler(struct netmsg *); 234 static int sysctl_eachburst(SYSCTL_HANDLER_ARGS); 235 236 /* 237 * Common functions 238 */ 239 static void poll_comm_init(int); 240 static void poll_comm_start(int); 241 static void poll_comm_adjust_pollhz(struct poll_comm *); 242 static void poll_comm_systimer0(systimer_t, struct intrframe *); 243 static void poll_comm_systimer(systimer_t, struct intrframe *); 244 static void sysctl_pollhz_handler(struct netmsg *); 245 static void sysctl_stfrac_handler(struct netmsg *); 246 static void sysctl_txfrac_handler(struct netmsg *); 247 static int sysctl_pollhz(SYSCTL_HANDLER_ARGS); 248 static int sysctl_stfrac(SYSCTL_HANDLER_ARGS); 249 static int sysctl_txfrac(SYSCTL_HANDLER_ARGS); 250 251 static struct stpoll_ctx stpoll_context; 252 static struct poll_comm *poll_common[IFPOLL_CTX_MAX]; 253 static struct iopoll_ctx *rxpoll_context[IFPOLL_CTX_MAX]; 254 static struct iopoll_ctx *txpoll_context[IFPOLL_CTX_MAX]; 255 256 SYSCTL_NODE(_net, OID_AUTO, ifpoll, CTLFLAG_RW, 0, 257 "Network device polling parameters"); 258 259 static int ifpoll_ncpus = IFPOLL_CTX_MAX; 260 261 static int iopoll_burst_max = IOPOLL_BURST_MAX; 262 static int iopoll_each_burst = IOPOLL_EACH_BURST; 263 264 static int ifpoll_pollhz = IFPOLL_FREQ_DEFAULT; 265 static int ifpoll_stfrac = IFPOLL_STFRAC_DEFAULT; 266 static int ifpoll_txfrac = IFPOLL_TXFRAC_DEFAULT; 267 268 TUNABLE_INT("net.ifpoll.burst_max", &iopoll_burst_max); 269 TUNABLE_INT("net.ifpoll.each_burst", &iopoll_each_burst); 270 TUNABLE_INT("net.ifpoll.pollhz", &ifpoll_pollhz); 271 TUNABLE_INT("net.ifpoll.status_frac", &ifpoll_stfrac); 272 TUNABLE_INT("net.ifpoll.tx_frac", &ifpoll_txfrac); 273 274 static __inline void 275 ifpoll_sendmsg_oncpu(struct netmsg *msg) 276 { 277 if (msg->nm_lmsg.ms_flags & MSGF_DONE) 278 ifnet_sendmsg(&msg->nm_lmsg, mycpuid); 279 } 280 281 static __inline void 282 sched_stpoll(struct stpoll_ctx *st_ctx) 283 { 284 ifpoll_sendmsg_oncpu(&st_ctx->poll_netmsg); 285 } 286 287 static __inline void 288 sched_iopoll(struct iopoll_ctx *io_ctx) 289 { 290 ifpoll_sendmsg_oncpu(&io_ctx->poll_netmsg); 291 } 292 293 static __inline void 294 sched_iopollmore(struct iopoll_ctx *io_ctx) 295 { 296 ifpoll_sendmsg_oncpu(&io_ctx->poll_more_netmsg); 297 } 298 299 static __inline void 300 ifpoll_time_get(union ifpoll_time *t) 301 { 302 if (tsc_present) 303 t->tsc = rdtsc(); 304 else 305 microuptime(&t->tv); 306 } 307 308 /* Return time diff in us */ 309 static __inline int 310 ifpoll_time_diff(const union ifpoll_time *s, const union ifpoll_time *e) 311 { 312 if (tsc_present) { 313 return (((e->tsc - s->tsc) * 1000000) / tsc_frequency); 314 } else { 315 return ((e->tv.tv_usec - s->tv.tv_usec) + 316 (e->tv.tv_sec - s->tv.tv_sec) * 1000000); 317 } 318 } 319 320 /* 321 * Initialize per-cpu qpolling(4) context. Called from kern_clock.c: 322 */ 323 void 324 ifpoll_init_pcpu(int cpuid) 325 { 326 if (cpuid >= IFPOLL_CTX_MAX) 327 return; 328 329 if (cpuid == 0) { 330 if (ifpoll_ncpus > ncpus) 331 ifpoll_ncpus = ncpus; 332 if (bootverbose) 333 kprintf("ifpoll_ncpus %d\n", ifpoll_ncpus); 334 } 335 336 poll_comm_init(cpuid); 337 338 if (cpuid == 0) 339 stpoll_init(); 340 iopoll_init(cpuid); 341 342 poll_comm_start(cpuid); 343 } 344 345 int 346 ifpoll_register(struct ifnet *ifp) 347 { 348 struct ifpoll_info info; 349 struct netmsg nmsg; 350 int error; 351 352 if (ifp->if_qpoll == NULL) { 353 /* Device does not support polling */ 354 return EOPNOTSUPP; 355 } 356 357 /* 358 * Attempt to register. Interlock with IFF_NPOLLING. 359 */ 360 361 ifnet_serialize_all(ifp); 362 363 if (ifp->if_flags & IFF_NPOLLING) { 364 /* Already polling */ 365 ifnet_deserialize_all(ifp); 366 return EBUSY; 367 } 368 369 bzero(&info, sizeof(info)); 370 info.ifpi_ifp = ifp; 371 372 ifp->if_flags |= IFF_NPOLLING; 373 ifp->if_qpoll(ifp, &info); 374 375 ifnet_deserialize_all(ifp); 376 377 netmsg_init(&nmsg, NULL, &curthread->td_msgport, 378 0, ifpoll_register_handler); 379 nmsg.nm_lmsg.u.ms_resultp = &info; 380 381 error = ifnet_domsg(&nmsg.nm_lmsg, 0); 382 if (error) { 383 if (!ifpoll_deregister(ifp)) { 384 if_printf(ifp, "ifpoll_register: " 385 "ifpoll_deregister failed!\n"); 386 } 387 } 388 return error; 389 } 390 391 int 392 ifpoll_deregister(struct ifnet *ifp) 393 { 394 struct netmsg nmsg; 395 int error; 396 397 if (ifp->if_qpoll == NULL) 398 return EOPNOTSUPP; 399 400 ifnet_serialize_all(ifp); 401 402 if ((ifp->if_flags & IFF_NPOLLING) == 0) { 403 ifnet_deserialize_all(ifp); 404 return EINVAL; 405 } 406 ifp->if_flags &= ~IFF_NPOLLING; 407 408 ifnet_deserialize_all(ifp); 409 410 netmsg_init(&nmsg, NULL, &curthread->td_msgport, 411 0, ifpoll_deregister_handler); 412 nmsg.nm_lmsg.u.ms_resultp = ifp; 413 414 error = ifnet_domsg(&nmsg.nm_lmsg, 0); 415 if (!error) { 416 ifnet_serialize_all(ifp); 417 ifp->if_qpoll(ifp, NULL); 418 ifnet_deserialize_all(ifp); 419 } 420 return error; 421 } 422 423 static void 424 ifpoll_register_handler(struct netmsg *nmsg) 425 { 426 const struct ifpoll_info *info = nmsg->nm_lmsg.u.ms_resultp; 427 int cpuid = mycpuid, nextcpu; 428 int error; 429 430 KKASSERT(cpuid < ifpoll_ncpus); 431 KKASSERT(&curthread->td_msgport == ifnet_portfn(cpuid)); 432 433 if (cpuid == 0) { 434 error = stpoll_register(info->ifpi_ifp, &info->ifpi_status); 435 if (error) 436 goto failed; 437 } 438 439 error = iopoll_register(info->ifpi_ifp, rxpoll_context[cpuid], 440 &info->ifpi_rx[cpuid]); 441 if (error) 442 goto failed; 443 444 error = iopoll_register(info->ifpi_ifp, txpoll_context[cpuid], 445 &info->ifpi_tx[cpuid]); 446 if (error) 447 goto failed; 448 449 /* Adjust polling frequency, after all registration is done */ 450 poll_comm_adjust_pollhz(poll_common[cpuid]); 451 452 nextcpu = cpuid + 1; 453 if (nextcpu < ifpoll_ncpus) 454 ifnet_forwardmsg(&nmsg->nm_lmsg, nextcpu); 455 else 456 lwkt_replymsg(&nmsg->nm_lmsg, 0); 457 return; 458 failed: 459 lwkt_replymsg(&nmsg->nm_lmsg, error); 460 } 461 462 static void 463 ifpoll_deregister_handler(struct netmsg *nmsg) 464 { 465 struct ifnet *ifp = nmsg->nm_lmsg.u.ms_resultp; 466 int cpuid = mycpuid, nextcpu; 467 468 KKASSERT(cpuid < ifpoll_ncpus); 469 KKASSERT(&curthread->td_msgport == ifnet_portfn(cpuid)); 470 471 /* Ignore errors */ 472 if (cpuid == 0) 473 stpoll_deregister(ifp); 474 iopoll_deregister(ifp, rxpoll_context[cpuid]); 475 iopoll_deregister(ifp, txpoll_context[cpuid]); 476 477 /* Adjust polling frequency, after all deregistration is done */ 478 poll_comm_adjust_pollhz(poll_common[cpuid]); 479 480 nextcpu = cpuid + 1; 481 if (nextcpu < ifpoll_ncpus) 482 ifnet_forwardmsg(&nmsg->nm_lmsg, nextcpu); 483 else 484 lwkt_replymsg(&nmsg->nm_lmsg, 0); 485 } 486 487 static void 488 stpoll_init(void) 489 { 490 struct stpoll_ctx *st_ctx = &stpoll_context; 491 const struct poll_comm *comm = poll_common[0]; 492 493 st_ctx->pollhz = comm->pollhz / (comm->poll_stfrac + 1); 494 495 sysctl_ctx_init(&st_ctx->poll_sysctl_ctx); 496 st_ctx->poll_sysctl_tree = SYSCTL_ADD_NODE(&st_ctx->poll_sysctl_ctx, 497 SYSCTL_CHILDREN(comm->sysctl_tree), 498 OID_AUTO, "status", CTLFLAG_RD, 0, ""); 499 500 SYSCTL_ADD_UINT(&st_ctx->poll_sysctl_ctx, 501 SYSCTL_CHILDREN(st_ctx->poll_sysctl_tree), 502 OID_AUTO, "handlers", CTLFLAG_RD, 503 &st_ctx->poll_handlers, 0, 504 "Number of registered status poll handlers"); 505 506 netmsg_init(&st_ctx->poll_netmsg, NULL, &netisr_adone_rport, 507 0, stpoll_handler); 508 } 509 510 /* 511 * stpoll_handler is scheduled by sched_stpoll when appropriate, typically 512 * once per polling systimer tick. 513 */ 514 static void 515 stpoll_handler(struct netmsg *msg) 516 { 517 struct stpoll_ctx *st_ctx = &stpoll_context; 518 struct thread *td = curthread; 519 int i; 520 521 KKASSERT(&td->td_msgport == ifnet_portfn(0)); 522 523 crit_enter_quick(td); 524 525 /* Reply ASAP */ 526 lwkt_replymsg(&msg->nm_lmsg, 0); 527 528 if (st_ctx->poll_handlers == 0) { 529 crit_exit_quick(td); 530 return; 531 } 532 533 for (i = 0; i < st_ctx->poll_handlers; ++i) { 534 const struct stpoll_rec *rec = &st_ctx->pr[i]; 535 struct ifnet *ifp = rec->ifp; 536 537 if (!lwkt_serialize_try(rec->serializer)) 538 continue; 539 540 if ((ifp->if_flags & (IFF_RUNNING | IFF_NPOLLING)) == 541 (IFF_RUNNING | IFF_NPOLLING)) 542 rec->status_func(ifp, st_ctx->pollhz); 543 544 lwkt_serialize_exit(rec->serializer); 545 } 546 547 crit_exit_quick(td); 548 } 549 550 /* 551 * Hook from status poll systimer. Tries to schedule an status poll. 552 * NOTE: Caller should hold critical section. 553 */ 554 static void 555 stpoll_clock(struct stpoll_ctx *st_ctx) 556 { 557 KKASSERT(mycpuid == 0); 558 559 if (st_ctx->poll_handlers == 0) 560 return; 561 sched_stpoll(st_ctx); 562 } 563 564 static int 565 stpoll_register(struct ifnet *ifp, const struct ifpoll_status *st_rec) 566 { 567 struct stpoll_ctx *st_ctx = &stpoll_context; 568 int error; 569 570 KKASSERT(&curthread->td_msgport == ifnet_portfn(0)); 571 572 if (st_rec->status_func == NULL) 573 return 0; 574 575 /* 576 * Check if there is room. 577 */ 578 if (st_ctx->poll_handlers >= IFPOLL_LIST_LEN) { 579 /* 580 * List full, cannot register more entries. 581 * This should never happen; if it does, it is probably a 582 * broken driver trying to register multiple times. Checking 583 * this at runtime is expensive, and won't solve the problem 584 * anyways, so just report a few times and then give up. 585 */ 586 static int verbose = 10; /* XXX */ 587 588 if (verbose > 0) { 589 kprintf("status poll handlers list full, " 590 "maybe a broken driver ?\n"); 591 verbose--; 592 } 593 error = ENOENT; 594 } else { 595 struct stpoll_rec *rec = &st_ctx->pr[st_ctx->poll_handlers]; 596 597 rec->ifp = ifp; 598 rec->serializer = st_rec->serializer; 599 rec->status_func = st_rec->status_func; 600 601 st_ctx->poll_handlers++; 602 error = 0; 603 } 604 return error; 605 } 606 607 static int 608 stpoll_deregister(struct ifnet *ifp) 609 { 610 struct stpoll_ctx *st_ctx = &stpoll_context; 611 int i, error; 612 613 KKASSERT(&curthread->td_msgport == ifnet_portfn(0)); 614 615 for (i = 0; i < st_ctx->poll_handlers; ++i) { 616 if (st_ctx->pr[i].ifp == ifp) /* Found it */ 617 break; 618 } 619 if (i == st_ctx->poll_handlers) { 620 kprintf("stpoll_deregister: ifp not found!!!\n"); 621 error = ENOENT; 622 } else { 623 st_ctx->poll_handlers--; 624 if (i < st_ctx->poll_handlers) { 625 /* Last entry replaces this one. */ 626 st_ctx->pr[i] = st_ctx->pr[st_ctx->poll_handlers]; 627 } 628 error = 0; 629 } 630 return error; 631 } 632 633 static __inline void 634 iopoll_reset_state(struct iopoll_ctx *io_ctx) 635 { 636 crit_enter(); 637 io_ctx->poll_burst = 5; 638 io_ctx->pending_polls = 0; 639 io_ctx->residual_burst = 0; 640 io_ctx->phase = 0; 641 io_ctx->kern_frac = 0; 642 bzero(&io_ctx->poll_start_t, sizeof(io_ctx->poll_start_t)); 643 bzero(&io_ctx->prev_t, sizeof(io_ctx->prev_t)); 644 crit_exit(); 645 } 646 647 static void 648 iopoll_init(int cpuid) 649 { 650 KKASSERT(cpuid < IFPOLL_CTX_MAX); 651 652 rxpoll_context[cpuid] = iopoll_ctx_create(cpuid, IFPOLL_RX); 653 txpoll_context[cpuid] = iopoll_ctx_create(cpuid, IFPOLL_TX); 654 } 655 656 static struct iopoll_ctx * 657 iopoll_ctx_create(int cpuid, int poll_type) 658 { 659 struct poll_comm *comm; 660 struct iopoll_ctx *io_ctx; 661 const char *poll_type_str; 662 663 KKASSERT(poll_type == IFPOLL_RX || poll_type == IFPOLL_TX); 664 665 /* 666 * Make sure that tunables are in sane state 667 */ 668 if (iopoll_burst_max < MIN_IOPOLL_BURST_MAX) 669 iopoll_burst_max = MIN_IOPOLL_BURST_MAX; 670 else if (iopoll_burst_max > MAX_IOPOLL_BURST_MAX) 671 iopoll_burst_max = MAX_IOPOLL_BURST_MAX; 672 673 if (iopoll_each_burst > iopoll_burst_max) 674 iopoll_each_burst = iopoll_burst_max; 675 676 comm = poll_common[cpuid]; 677 678 /* 679 * Create the per-cpu polling context 680 */ 681 io_ctx = kmalloc(sizeof(*io_ctx), M_DEVBUF, M_WAITOK | M_ZERO); 682 683 io_ctx->poll_each_burst = iopoll_each_burst; 684 io_ctx->poll_burst_max = iopoll_burst_max; 685 io_ctx->user_frac = 50; 686 if (poll_type == IFPOLL_RX) 687 io_ctx->pollhz = comm->pollhz; 688 else 689 io_ctx->pollhz = comm->pollhz / (comm->poll_txfrac + 1); 690 io_ctx->poll_cpuid = cpuid; 691 iopoll_reset_state(io_ctx); 692 693 netmsg_init(&io_ctx->poll_netmsg, NULL, &netisr_adone_rport, 694 0, iopoll_handler); 695 io_ctx->poll_netmsg.nm_lmsg.u.ms_resultp = io_ctx; 696 697 netmsg_init(&io_ctx->poll_more_netmsg, NULL, &netisr_adone_rport, 698 0, iopollmore_handler); 699 io_ctx->poll_more_netmsg.nm_lmsg.u.ms_resultp = io_ctx; 700 701 /* 702 * Initialize per-cpu sysctl nodes 703 */ 704 if (poll_type == IFPOLL_RX) 705 poll_type_str = "rx"; 706 else 707 poll_type_str = "tx"; 708 709 sysctl_ctx_init(&io_ctx->poll_sysctl_ctx); 710 io_ctx->poll_sysctl_tree = SYSCTL_ADD_NODE(&io_ctx->poll_sysctl_ctx, 711 SYSCTL_CHILDREN(comm->sysctl_tree), 712 OID_AUTO, poll_type_str, CTLFLAG_RD, 0, ""); 713 iopoll_add_sysctl(&io_ctx->poll_sysctl_ctx, 714 SYSCTL_CHILDREN(io_ctx->poll_sysctl_tree), io_ctx); 715 716 return io_ctx; 717 } 718 719 /* 720 * Hook from iopoll systimer. Tries to schedule an iopoll, but keeps 721 * track of lost ticks due to the previous handler taking too long. 722 * Normally, this should not happen, because polling handler should 723 * run for a short time. However, in some cases (e.g. when there are 724 * changes in link status etc.) the drivers take a very long time 725 * (even in the order of milliseconds) to reset and reconfigure the 726 * device, causing apparent lost polls. 727 * 728 * The first part of the code is just for debugging purposes, and tries 729 * to count how often hardclock ticks are shorter than they should, 730 * meaning either stray interrupts or delayed events. 731 * 732 * WARNING! called from fastint or IPI, the MP lock might not be held. 733 * NOTE: Caller should hold critical section. 734 */ 735 static void 736 iopoll_clock(struct iopoll_ctx *io_ctx) 737 { 738 union ifpoll_time t; 739 int delta; 740 741 KKASSERT(mycpuid == io_ctx->poll_cpuid); 742 743 if (io_ctx->poll_handlers == 0) 744 return; 745 746 ifpoll_time_get(&t); 747 delta = ifpoll_time_diff(&io_ctx->prev_t, &t); 748 if (delta * io_ctx->pollhz < 500000) 749 io_ctx->short_ticks++; 750 else 751 io_ctx->prev_t = t; 752 753 if (io_ctx->pending_polls > 100) { 754 /* 755 * Too much, assume it has stalled (not always true 756 * see comment above). 757 */ 758 io_ctx->stalled++; 759 io_ctx->pending_polls = 0; 760 io_ctx->phase = 0; 761 } 762 763 if (io_ctx->phase <= 2) { 764 if (io_ctx->phase != 0) 765 io_ctx->suspect++; 766 io_ctx->phase = 1; 767 sched_iopoll(io_ctx); 768 io_ctx->phase = 2; 769 } 770 if (io_ctx->pending_polls++ > 0) 771 io_ctx->lost_polls++; 772 } 773 774 /* 775 * iopoll_handler is scheduled by sched_iopoll when appropriate, typically 776 * once per polling systimer tick. 777 * 778 * Note that the message is replied immediately in order to allow a new 779 * ISR to be scheduled in the handler. 780 */ 781 static void 782 iopoll_handler(struct netmsg *msg) 783 { 784 struct iopoll_ctx *io_ctx; 785 struct thread *td = curthread; 786 int i, cycles; 787 788 io_ctx = msg->nm_lmsg.u.ms_resultp; 789 KKASSERT(&td->td_msgport == ifnet_portfn(io_ctx->poll_cpuid)); 790 791 crit_enter_quick(td); 792 793 /* Reply ASAP */ 794 lwkt_replymsg(&msg->nm_lmsg, 0); 795 796 if (io_ctx->poll_handlers == 0) { 797 crit_exit_quick(td); 798 return; 799 } 800 801 io_ctx->phase = 3; 802 if (io_ctx->residual_burst == 0) { 803 /* First call in this tick */ 804 ifpoll_time_get(&io_ctx->poll_start_t); 805 io_ctx->residual_burst = io_ctx->poll_burst; 806 } 807 cycles = (io_ctx->residual_burst < io_ctx->poll_each_burst) ? 808 io_ctx->residual_burst : io_ctx->poll_each_burst; 809 io_ctx->residual_burst -= cycles; 810 811 for (i = 0; i < io_ctx->poll_handlers; i++) { 812 const struct iopoll_rec *rec = &io_ctx->pr[i]; 813 struct ifnet *ifp = rec->ifp; 814 815 if (!lwkt_serialize_try(rec->serializer)) 816 continue; 817 818 if ((ifp->if_flags & (IFF_RUNNING | IFF_NPOLLING)) == 819 (IFF_RUNNING | IFF_NPOLLING)) 820 rec->poll_func(ifp, rec->arg, cycles); 821 822 lwkt_serialize_exit(rec->serializer); 823 } 824 825 /* 826 * Do a quick exit/enter to catch any higher-priority 827 * interrupt sources. 828 */ 829 crit_exit_quick(td); 830 crit_enter_quick(td); 831 832 sched_iopollmore(io_ctx); 833 io_ctx->phase = 4; 834 835 crit_exit_quick(td); 836 } 837 838 /* 839 * iopollmore_handler is called after other netisr's, possibly scheduling 840 * another iopoll_handler call, or adapting the burst size for the next cycle. 841 * 842 * It is very bad to fetch large bursts of packets from a single card at once, 843 * because the burst could take a long time to be completely processed leading 844 * to unfairness. To reduce the problem, and also to account better for time 845 * spent in network-related processing, we split the burst in smaller chunks 846 * of fixed size, giving control to the other netisr's between chunks. This 847 * helps in improving the fairness, reducing livelock and accounting for the 848 * work performed in low level handling. 849 */ 850 static void 851 iopollmore_handler(struct netmsg *msg) 852 { 853 struct thread *td = curthread; 854 struct iopoll_ctx *io_ctx; 855 union ifpoll_time t; 856 int kern_load; 857 uint32_t pending_polls; 858 859 io_ctx = msg->nm_lmsg.u.ms_resultp; 860 KKASSERT(&td->td_msgport == ifnet_portfn(io_ctx->poll_cpuid)); 861 862 crit_enter_quick(td); 863 864 /* Replay ASAP */ 865 lwkt_replymsg(&msg->nm_lmsg, 0); 866 867 if (io_ctx->poll_handlers == 0) { 868 crit_exit_quick(td); 869 return; 870 } 871 872 io_ctx->phase = 5; 873 if (io_ctx->residual_burst > 0) { 874 sched_iopoll(io_ctx); 875 crit_exit_quick(td); 876 /* Will run immediately on return, followed by netisrs */ 877 return; 878 } 879 880 /* Here we can account time spent in iopoll's in this tick */ 881 ifpoll_time_get(&t); 882 kern_load = ifpoll_time_diff(&io_ctx->poll_start_t, &t); 883 kern_load = (kern_load * io_ctx->pollhz) / 10000; /* 0..100 */ 884 io_ctx->kern_frac = kern_load; 885 886 if (kern_load > (100 - io_ctx->user_frac)) { 887 /* Try decrease ticks */ 888 if (io_ctx->poll_burst > 1) 889 io_ctx->poll_burst--; 890 } else { 891 if (io_ctx->poll_burst < io_ctx->poll_burst_max) 892 io_ctx->poll_burst++; 893 } 894 895 io_ctx->pending_polls--; 896 pending_polls = io_ctx->pending_polls; 897 898 if (pending_polls == 0) { 899 /* We are done */ 900 io_ctx->phase = 0; 901 } else { 902 /* 903 * Last cycle was long and caused us to miss one or more 904 * hardclock ticks. Restart processing again, but slightly 905 * reduce the burst size to prevent that this happens again. 906 */ 907 io_ctx->poll_burst -= (io_ctx->poll_burst / 8); 908 if (io_ctx->poll_burst < 1) 909 io_ctx->poll_burst = 1; 910 sched_iopoll(io_ctx); 911 io_ctx->phase = 6; 912 } 913 914 crit_exit_quick(td); 915 } 916 917 static void 918 iopoll_add_sysctl(struct sysctl_ctx_list *ctx, struct sysctl_oid_list *parent, 919 struct iopoll_ctx *io_ctx) 920 { 921 SYSCTL_ADD_PROC(ctx, parent, OID_AUTO, "burst_max", 922 CTLTYPE_UINT | CTLFLAG_RW, io_ctx, 0, sysctl_burstmax, 923 "IU", "Max Polling burst size"); 924 925 SYSCTL_ADD_PROC(ctx, parent, OID_AUTO, "each_burst", 926 CTLTYPE_UINT | CTLFLAG_RW, io_ctx, 0, sysctl_eachburst, 927 "IU", "Max size of each burst"); 928 929 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "phase", CTLFLAG_RD, 930 &io_ctx->phase, 0, "Polling phase"); 931 932 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "suspect", CTLFLAG_RW, 933 &io_ctx->suspect, 0, "suspect event"); 934 935 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "stalled", CTLFLAG_RW, 936 &io_ctx->stalled, 0, "potential stalls"); 937 938 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "burst", CTLFLAG_RD, 939 &io_ctx->poll_burst, 0, "Current polling burst size"); 940 941 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "user_frac", CTLFLAG_RW, 942 &io_ctx->user_frac, 0, 943 "Desired user fraction of cpu time"); 944 945 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "kern_frac", CTLFLAG_RD, 946 &io_ctx->kern_frac, 0, 947 "Kernel fraction of cpu time"); 948 949 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "short_ticks", CTLFLAG_RW, 950 &io_ctx->short_ticks, 0, 951 "Hardclock ticks shorter than they should be"); 952 953 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "lost_polls", CTLFLAG_RW, 954 &io_ctx->lost_polls, 0, 955 "How many times we would have lost a poll tick"); 956 957 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "pending_polls", CTLFLAG_RD, 958 &io_ctx->pending_polls, 0, "Do we need to poll again"); 959 960 SYSCTL_ADD_INT(ctx, parent, OID_AUTO, "residual_burst", CTLFLAG_RD, 961 &io_ctx->residual_burst, 0, 962 "# of residual cycles in burst"); 963 964 SYSCTL_ADD_UINT(ctx, parent, OID_AUTO, "handlers", CTLFLAG_RD, 965 &io_ctx->poll_handlers, 0, 966 "Number of registered poll handlers"); 967 } 968 969 static void 970 sysctl_burstmax_handler(struct netmsg *nmsg) 971 { 972 struct iopoll_sysctl_netmsg *msg = (struct iopoll_sysctl_netmsg *)nmsg; 973 struct iopoll_ctx *io_ctx; 974 975 io_ctx = msg->ctx; 976 KKASSERT(&curthread->td_msgport == ifnet_portfn(io_ctx->poll_cpuid)); 977 978 io_ctx->poll_burst_max = nmsg->nm_lmsg.u.ms_result; 979 if (io_ctx->poll_each_burst > io_ctx->poll_burst_max) 980 io_ctx->poll_each_burst = io_ctx->poll_burst_max; 981 if (io_ctx->poll_burst > io_ctx->poll_burst_max) 982 io_ctx->poll_burst = io_ctx->poll_burst_max; 983 if (io_ctx->residual_burst > io_ctx->poll_burst_max) 984 io_ctx->residual_burst = io_ctx->poll_burst_max; 985 986 lwkt_replymsg(&nmsg->nm_lmsg, 0); 987 } 988 989 static int 990 sysctl_burstmax(SYSCTL_HANDLER_ARGS) 991 { 992 struct iopoll_ctx *io_ctx = arg1; 993 struct iopoll_sysctl_netmsg msg; 994 struct netmsg *nmsg; 995 uint32_t burst_max; 996 int error; 997 998 burst_max = io_ctx->poll_burst_max; 999 error = sysctl_handle_int(oidp, &burst_max, 0, req); 1000 if (error || req->newptr == NULL) 1001 return error; 1002 if (burst_max < MIN_IOPOLL_BURST_MAX) 1003 burst_max = MIN_IOPOLL_BURST_MAX; 1004 else if (burst_max > MAX_IOPOLL_BURST_MAX) 1005 burst_max = MAX_IOPOLL_BURST_MAX; 1006 1007 nmsg = &msg.nmsg; 1008 netmsg_init(nmsg, NULL, &curthread->td_msgport, 1009 0, sysctl_burstmax_handler); 1010 nmsg->nm_lmsg.u.ms_result = burst_max; 1011 msg.ctx = io_ctx; 1012 1013 return ifnet_domsg(&nmsg->nm_lmsg, io_ctx->poll_cpuid); 1014 } 1015 1016 static void 1017 sysctl_eachburst_handler(struct netmsg *nmsg) 1018 { 1019 struct iopoll_sysctl_netmsg *msg = (struct iopoll_sysctl_netmsg *)nmsg; 1020 struct iopoll_ctx *io_ctx; 1021 uint32_t each_burst; 1022 1023 io_ctx = msg->ctx; 1024 KKASSERT(&curthread->td_msgport == ifnet_portfn(io_ctx->poll_cpuid)); 1025 1026 each_burst = nmsg->nm_lmsg.u.ms_result; 1027 if (each_burst > io_ctx->poll_burst_max) 1028 each_burst = io_ctx->poll_burst_max; 1029 else if (each_burst < 1) 1030 each_burst = 1; 1031 io_ctx->poll_each_burst = each_burst; 1032 1033 lwkt_replymsg(&nmsg->nm_lmsg, 0); 1034 } 1035 1036 static int 1037 sysctl_eachburst(SYSCTL_HANDLER_ARGS) 1038 { 1039 struct iopoll_ctx *io_ctx = arg1; 1040 struct iopoll_sysctl_netmsg msg; 1041 struct netmsg *nmsg; 1042 uint32_t each_burst; 1043 int error; 1044 1045 each_burst = io_ctx->poll_each_burst; 1046 error = sysctl_handle_int(oidp, &each_burst, 0, req); 1047 if (error || req->newptr == NULL) 1048 return error; 1049 1050 nmsg = &msg.nmsg; 1051 netmsg_init(nmsg, NULL, &curthread->td_msgport, 1052 0, sysctl_eachburst_handler); 1053 nmsg->nm_lmsg.u.ms_result = each_burst; 1054 msg.ctx = io_ctx; 1055 1056 return ifnet_domsg(&nmsg->nm_lmsg, io_ctx->poll_cpuid); 1057 } 1058 1059 static int 1060 iopoll_register(struct ifnet *ifp, struct iopoll_ctx *io_ctx, 1061 const struct ifpoll_io *io_rec) 1062 { 1063 int error; 1064 1065 KKASSERT(&curthread->td_msgport == ifnet_portfn(io_ctx->poll_cpuid)); 1066 1067 if (io_rec->poll_func == NULL) 1068 return 0; 1069 1070 /* 1071 * Check if there is room. 1072 */ 1073 if (io_ctx->poll_handlers >= IFPOLL_LIST_LEN) { 1074 /* 1075 * List full, cannot register more entries. 1076 * This should never happen; if it does, it is probably a 1077 * broken driver trying to register multiple times. Checking 1078 * this at runtime is expensive, and won't solve the problem 1079 * anyways, so just report a few times and then give up. 1080 */ 1081 static int verbose = 10; /* XXX */ 1082 if (verbose > 0) { 1083 kprintf("io poll handlers list full, " 1084 "maybe a broken driver ?\n"); 1085 verbose--; 1086 } 1087 error = ENOENT; 1088 } else { 1089 struct iopoll_rec *rec = &io_ctx->pr[io_ctx->poll_handlers]; 1090 1091 rec->ifp = ifp; 1092 rec->serializer = io_rec->serializer; 1093 rec->arg = io_rec->arg; 1094 rec->poll_func = io_rec->poll_func; 1095 1096 io_ctx->poll_handlers++; 1097 error = 0; 1098 } 1099 return error; 1100 } 1101 1102 static int 1103 iopoll_deregister(struct ifnet *ifp, struct iopoll_ctx *io_ctx) 1104 { 1105 int i, error; 1106 1107 KKASSERT(&curthread->td_msgport == ifnet_portfn(io_ctx->poll_cpuid)); 1108 1109 for (i = 0; i < io_ctx->poll_handlers; ++i) { 1110 if (io_ctx->pr[i].ifp == ifp) /* Found it */ 1111 break; 1112 } 1113 if (i == io_ctx->poll_handlers) { 1114 error = ENOENT; 1115 } else { 1116 io_ctx->poll_handlers--; 1117 if (i < io_ctx->poll_handlers) { 1118 /* Last entry replaces this one. */ 1119 io_ctx->pr[i] = io_ctx->pr[io_ctx->poll_handlers]; 1120 } 1121 1122 if (io_ctx->poll_handlers == 0) 1123 iopoll_reset_state(io_ctx); 1124 error = 0; 1125 } 1126 return error; 1127 } 1128 1129 static void 1130 poll_comm_init(int cpuid) 1131 { 1132 struct poll_comm *comm; 1133 char cpuid_str[16]; 1134 1135 comm = kmalloc(sizeof(*comm), M_DEVBUF, M_WAITOK | M_ZERO); 1136 1137 if (ifpoll_stfrac < 0) 1138 ifpoll_stfrac = IFPOLL_STFRAC_DEFAULT; 1139 if (ifpoll_txfrac < 0) 1140 ifpoll_txfrac = IFPOLL_TXFRAC_DEFAULT; 1141 1142 comm->pollhz = ifpoll_pollhz; 1143 comm->poll_cpuid = cpuid; 1144 comm->poll_stfrac = ifpoll_stfrac; 1145 comm->poll_txfrac = ifpoll_txfrac; 1146 1147 ksnprintf(cpuid_str, sizeof(cpuid_str), "%d", cpuid); 1148 1149 sysctl_ctx_init(&comm->sysctl_ctx); 1150 comm->sysctl_tree = SYSCTL_ADD_NODE(&comm->sysctl_ctx, 1151 SYSCTL_STATIC_CHILDREN(_net_ifpoll), 1152 OID_AUTO, cpuid_str, CTLFLAG_RD, 0, ""); 1153 1154 SYSCTL_ADD_PROC(&comm->sysctl_ctx, SYSCTL_CHILDREN(comm->sysctl_tree), 1155 OID_AUTO, "pollhz", CTLTYPE_INT | CTLFLAG_RW, 1156 comm, 0, sysctl_pollhz, 1157 "I", "Device polling frequency"); 1158 1159 if (cpuid == 0) { 1160 SYSCTL_ADD_PROC(&comm->sysctl_ctx, 1161 SYSCTL_CHILDREN(comm->sysctl_tree), 1162 OID_AUTO, "status_frac", 1163 CTLTYPE_INT | CTLFLAG_RW, 1164 comm, 0, sysctl_stfrac, 1165 "I", "# of cycles before status is polled"); 1166 } 1167 SYSCTL_ADD_PROC(&comm->sysctl_ctx, SYSCTL_CHILDREN(comm->sysctl_tree), 1168 OID_AUTO, "tx_frac", CTLTYPE_INT | CTLFLAG_RW, 1169 comm, 0, sysctl_txfrac, 1170 "I", "# of cycles before TX is polled"); 1171 1172 poll_common[cpuid] = comm; 1173 } 1174 1175 static void 1176 poll_comm_start(int cpuid) 1177 { 1178 struct poll_comm *comm = poll_common[cpuid]; 1179 void (*func)(systimer_t, struct intrframe *); 1180 1181 /* 1182 * Initialize systimer 1183 */ 1184 if (cpuid == 0) 1185 func = poll_comm_systimer0; 1186 else 1187 func = poll_comm_systimer; 1188 systimer_init_periodic_nq(&comm->pollclock, func, comm, 1); 1189 } 1190 1191 static void 1192 _poll_comm_systimer(struct poll_comm *comm) 1193 { 1194 if (comm->txfrac_count-- == 0) { 1195 comm->txfrac_count = comm->poll_txfrac; 1196 iopoll_clock(txpoll_context[comm->poll_cpuid]); 1197 } 1198 iopoll_clock(rxpoll_context[comm->poll_cpuid]); 1199 } 1200 1201 static void 1202 poll_comm_systimer0(systimer_t info, struct intrframe *frame __unused) 1203 { 1204 struct poll_comm *comm = info->data; 1205 globaldata_t gd = mycpu; 1206 1207 KKASSERT(comm->poll_cpuid == gd->gd_cpuid && gd->gd_cpuid == 0); 1208 1209 crit_enter_gd(gd); 1210 1211 if (comm->stfrac_count-- == 0) { 1212 comm->stfrac_count = comm->poll_stfrac; 1213 stpoll_clock(&stpoll_context); 1214 } 1215 _poll_comm_systimer(comm); 1216 1217 crit_exit_gd(gd); 1218 } 1219 1220 static void 1221 poll_comm_systimer(systimer_t info, struct intrframe *frame __unused) 1222 { 1223 struct poll_comm *comm = info->data; 1224 globaldata_t gd = mycpu; 1225 1226 KKASSERT(comm->poll_cpuid == gd->gd_cpuid && gd->gd_cpuid != 0); 1227 1228 crit_enter_gd(gd); 1229 _poll_comm_systimer(comm); 1230 crit_exit_gd(gd); 1231 } 1232 1233 static void 1234 poll_comm_adjust_pollhz(struct poll_comm *comm) 1235 { 1236 uint32_t handlers; 1237 int pollhz = 1; 1238 1239 KKASSERT(&curthread->td_msgport == ifnet_portfn(comm->poll_cpuid)); 1240 1241 /* 1242 * If there is no polling handler registered, set systimer 1243 * frequency to the lowest value. Polling systimer frequency 1244 * will be adjusted to the requested value, once there are 1245 * registered handlers. 1246 */ 1247 handlers = rxpoll_context[mycpuid]->poll_handlers + 1248 txpoll_context[mycpuid]->poll_handlers; 1249 if (comm->poll_cpuid == 0) 1250 handlers += stpoll_context.poll_handlers; 1251 if (handlers) 1252 pollhz = comm->pollhz; 1253 systimer_adjust_periodic(&comm->pollclock, pollhz); 1254 } 1255 1256 static int 1257 sysctl_pollhz(SYSCTL_HANDLER_ARGS) 1258 { 1259 struct poll_comm *comm = arg1; 1260 struct netmsg nmsg; 1261 int error, phz; 1262 1263 phz = comm->pollhz; 1264 error = sysctl_handle_int(oidp, &phz, 0, req); 1265 if (error || req->newptr == NULL) 1266 return error; 1267 if (phz <= 0) 1268 return EINVAL; 1269 else if (phz > IFPOLL_FREQ_MAX) 1270 phz = IFPOLL_FREQ_MAX; 1271 1272 netmsg_init(&nmsg, NULL, &curthread->td_msgport, 1273 0, sysctl_pollhz_handler); 1274 nmsg.nm_lmsg.u.ms_result = phz; 1275 1276 return ifnet_domsg(&nmsg.nm_lmsg, comm->poll_cpuid); 1277 } 1278 1279 static void 1280 sysctl_pollhz_handler(struct netmsg *nmsg) 1281 { 1282 struct poll_comm *comm = poll_common[mycpuid]; 1283 1284 KKASSERT(&curthread->td_msgport == ifnet_portfn(comm->poll_cpuid)); 1285 1286 /* Save polling frequency */ 1287 comm->pollhz = nmsg->nm_lmsg.u.ms_result; 1288 1289 /* 1290 * Adjust cached pollhz 1291 */ 1292 rxpoll_context[mycpuid]->pollhz = comm->pollhz; 1293 txpoll_context[mycpuid]->pollhz = 1294 comm->pollhz / (comm->poll_txfrac + 1); 1295 if (mycpuid == 0) 1296 stpoll_context.pollhz = comm->pollhz / (comm->poll_stfrac + 1); 1297 1298 /* 1299 * Adjust polling frequency 1300 */ 1301 poll_comm_adjust_pollhz(comm); 1302 1303 lwkt_replymsg(&nmsg->nm_lmsg, 0); 1304 } 1305 1306 static int 1307 sysctl_stfrac(SYSCTL_HANDLER_ARGS) 1308 { 1309 struct poll_comm *comm = arg1; 1310 struct netmsg nmsg; 1311 int error, stfrac; 1312 1313 KKASSERT(comm->poll_cpuid == 0); 1314 1315 stfrac = comm->poll_stfrac; 1316 error = sysctl_handle_int(oidp, &stfrac, 0, req); 1317 if (error || req->newptr == NULL) 1318 return error; 1319 if (stfrac < 0) 1320 return EINVAL; 1321 1322 netmsg_init(&nmsg, NULL, &curthread->td_msgport, 1323 0, sysctl_stfrac_handler); 1324 nmsg.nm_lmsg.u.ms_result = stfrac; 1325 1326 return ifnet_domsg(&nmsg.nm_lmsg, comm->poll_cpuid); 1327 } 1328 1329 static void 1330 sysctl_stfrac_handler(struct netmsg *nmsg) 1331 { 1332 struct poll_comm *comm = poll_common[mycpuid]; 1333 int stfrac = nmsg->nm_lmsg.u.ms_result; 1334 1335 KKASSERT(&curthread->td_msgport == ifnet_portfn(comm->poll_cpuid)); 1336 1337 crit_enter(); 1338 comm->poll_stfrac = stfrac; 1339 if (comm->stfrac_count > comm->poll_stfrac) 1340 comm->stfrac_count = comm->poll_stfrac; 1341 crit_exit(); 1342 1343 lwkt_replymsg(&nmsg->nm_lmsg, 0); 1344 } 1345 1346 static int 1347 sysctl_txfrac(SYSCTL_HANDLER_ARGS) 1348 { 1349 struct poll_comm *comm = arg1; 1350 struct netmsg nmsg; 1351 int error, txfrac; 1352 1353 txfrac = comm->poll_txfrac; 1354 error = sysctl_handle_int(oidp, &txfrac, 0, req); 1355 if (error || req->newptr == NULL) 1356 return error; 1357 if (txfrac < 0) 1358 return EINVAL; 1359 1360 netmsg_init(&nmsg, NULL, &curthread->td_msgport, 1361 0, sysctl_txfrac_handler); 1362 nmsg.nm_lmsg.u.ms_result = txfrac; 1363 1364 return ifnet_domsg(&nmsg.nm_lmsg, comm->poll_cpuid); 1365 } 1366 1367 static void 1368 sysctl_txfrac_handler(struct netmsg *nmsg) 1369 { 1370 struct poll_comm *comm = poll_common[mycpuid]; 1371 int txfrac = nmsg->nm_lmsg.u.ms_result; 1372 1373 KKASSERT(&curthread->td_msgport == ifnet_portfn(comm->poll_cpuid)); 1374 1375 crit_enter(); 1376 comm->poll_txfrac = txfrac; 1377 if (comm->txfrac_count > comm->poll_txfrac) 1378 comm->txfrac_count = comm->poll_txfrac; 1379 crit_exit(); 1380 1381 lwkt_replymsg(&nmsg->nm_lmsg, 0); 1382 } 1383