lib/librte_eal/linuxapp/eal/eal_interrupts.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <stdio.h>
  35 #include <stdint.h>
  36 #include <stdlib.h>
  37 #include <pthread.h>
  38 #include <sys/queue.h>
  39 #include <stdarg.h>
  40 #include <unistd.h>
  41 #include <string.h>
  42 #include <errno.h>
  43 #include <inttypes.h>
  44 #include <sys/epoll.h>
  45 #include <sys/signalfd.h>
  46 #include <sys/ioctl.h>
  47 #include <sys/eventfd.h>
  48 #include <assert.h>
  49
  50 #include <rte_common.h>
  51 #include <rte_interrupts.h>
  52 #include <rte_memory.h>
  53 #include <rte_memzone.h>
  54 #include <rte_launch.h>
  55 #include <rte_eal.h>
  56 #include <rte_per_lcore.h>
  57 #include <rte_lcore.h>
  58 #include <rte_atomic.h>
  59 #include <rte_branch_prediction.h>
  60 #include <rte_debug.h>
  61 #include <rte_log.h>
  62 #include <rte_pci.h>
  63 #include <rte_malloc.h>
  64 #include <rte_errno.h>
  65 #include <rte_spinlock.h>
  66
  67 #include "eal_private.h"
  68 #include "eal_vfio.h"
  69 #include "eal_thread.h"
  70
  71 #define EAL_INTR_EPOLL_WAIT_FOREVER (-1)
  72 #define NB_OTHER_INTR               1
  73
  74 static RTE_DEFINE_PER_LCORE(int, _epfd) = -1; /**< epoll fd per thread */
  75
  76 /**
  77  * union for pipe fds.
  78  */
  79 union intr_pipefds{
  80         struct {
  81                 int pipefd[2];
  82         };
  83         struct {
  84                 int readfd;
  85                 int writefd;
  86         };
  87 };
  88
  89 /**
  90  * union buffer for reading on different devices
  91  */
  92 union rte_intr_read_buffer {
  93         int uio_intr_count;              /* for uio device */
  94 #ifdef VFIO_PRESENT
  95         uint64_t vfio_intr_count;        /* for vfio device */
  96 #endif
  97         uint64_t timerfd_num;            /* for timerfd */
  98         char charbuf[16];                /* for others */
  99 };
 100
 101 TAILQ_HEAD(rte_intr_cb_list, rte_intr_callback);
 102 TAILQ_HEAD(rte_intr_source_list, rte_intr_source);
 103
 104 struct rte_intr_callback {
 105         TAILQ_ENTRY(rte_intr_callback) next;
 106         rte_intr_callback_fn cb_fn;  /**< callback address */
 107         void *cb_arg;                /**< parameter for callback */
 108 };
 109
 110 struct rte_intr_source {
 111         TAILQ_ENTRY(rte_intr_source) next;
 112         struct rte_intr_handle intr_handle; /**< interrupt handle */
 113         struct rte_intr_cb_list callbacks;  /**< user callbacks */
 114         uint32_t active;
 115 };
 116
 117 /* global spinlock for interrupt data operation */
 118 static rte_spinlock_t intr_lock = RTE_SPINLOCK_INITIALIZER;
 119
 120 /* union buffer for pipe read/write */
 121 static union intr_pipefds intr_pipe;
 122
 123 /* interrupt sources list */
 124 static struct rte_intr_source_list intr_sources;
 125
 126 /* interrupt handling thread */
 127 static pthread_t intr_thread;
 128
 129 /* VFIO interrupts */
 130 #ifdef VFIO_PRESENT
 131
 132 #define IRQ_SET_BUF_LEN  (sizeof(struct vfio_irq_set) + sizeof(int))
 133 /* irq set buffer length for queue interrupts and LSC interrupt */
 134 #define MSIX_IRQ_SET_BUF_LEN (sizeof(struct vfio_irq_set) + \
 135                               sizeof(int) * (RTE_MAX_RXTX_INTR_VEC_ID + 1))
 136
 137 /* enable legacy (INTx) interrupts */
 138 static int
 139 vfio_enable_intx(struct rte_intr_handle *intr_handle) {
 140         struct vfio_irq_set *irq_set;
 141         char irq_set_buf[IRQ_SET_BUF_LEN];
 142         int len, ret;
 143         int *fd_ptr;
 144
 145         len = sizeof(irq_set_buf);
 146
 147         /* enable INTx */
 148         irq_set = (struct vfio_irq_set *) irq_set_buf;
 149         irq_set->argsz = len;
 150         irq_set->count = 1;
 151         irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER;
 152         irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
 153         irq_set->start = 0;
 154         fd_ptr = (int *) &irq_set->data;
 155         *fd_ptr = intr_handle->fd;
 156
 157         ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
 158
 159         if (ret) {
 160                 RTE_LOG(ERR, EAL, "Error enabling INTx interrupts for fd %d\n",
 161                                                 intr_handle->fd);
 162                 return -1;
 163         }
 164
 165         /* unmask INTx after enabling */
 166         memset(irq_set, 0, len);
 167         len = sizeof(struct vfio_irq_set);
 168         irq_set->argsz = len;
 169         irq_set->count = 1;
 170         irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK;
 171         irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
 172         irq_set->start = 0;
 173
 174         ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
 175
 176         if (ret) {
 177                 RTE_LOG(ERR, EAL, "Error unmasking INTx interrupts for fd %d\n",
 178                                                 intr_handle->fd);
 179                 return -1;
 180         }
 181         return 0;
 182 }
 183
 184 /* disable legacy (INTx) interrupts */
 185 static int
 186 vfio_disable_intx(struct rte_intr_handle *intr_handle) {
 187         struct vfio_irq_set *irq_set;
 188         char irq_set_buf[IRQ_SET_BUF_LEN];
 189         int len, ret;
 190
 191         len = sizeof(struct vfio_irq_set);
 192
 193         /* mask interrupts before disabling */
 194         irq_set = (struct vfio_irq_set *) irq_set_buf;
 195         irq_set->argsz = len;
 196         irq_set->count = 1;
 197         irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK;
 198         irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
 199         irq_set->start = 0;
 200
 201         ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
 202
 203         if (ret) {
 204                 RTE_LOG(ERR, EAL, "Error masking INTx interrupts for fd %d\n",
 205                                                 intr_handle->fd);
 206                 return -1;
 207         }
 208
 209         /* disable INTx*/
 210         memset(irq_set, 0, len);
 211         irq_set->argsz = len;
 212         irq_set->count = 0;
 213         irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER;
 214         irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
 215         irq_set->start = 0;
 216
 217         ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
 218
 219         if (ret) {
 220                 RTE_LOG(ERR, EAL,
 221                         "Error disabling INTx interrupts for fd %d\n", intr_handle->fd);
 222                 return -1;
 223         }
 224         return 0;
 225 }
 226
 227 /* enable MSI interrupts */
 228 static int
 229 vfio_enable_msi(struct rte_intr_handle *intr_handle) {
 230         int len, ret;
 231         char irq_set_buf[IRQ_SET_BUF_LEN];
 232         struct vfio_irq_set *irq_set;
 233         int *fd_ptr;
 234
 235         len = sizeof(irq_set_buf);
 236
 237         irq_set = (struct vfio_irq_set *) irq_set_buf;
 238         irq_set->argsz = len;
 239         irq_set->count = 1;
 240         irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER;
 241         irq_set->index = VFIO_PCI_MSI_IRQ_INDEX;
 242         irq_set->start = 0;
 243         fd_ptr = (int *) &irq_set->data;
 244         *fd_ptr = intr_handle->fd;
 245
 246         ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
 247
 248         if (ret) {
 249                 RTE_LOG(ERR, EAL, "Error enabling MSI interrupts for fd %d\n",
 250                                                 intr_handle->fd);
 251                 return -1;
 252         }
 253         return 0;
 254 }
 255
 256 /* disable MSI interrupts */
 257 static int
 258 vfio_disable_msi(struct rte_intr_handle *intr_handle) {
 259         struct vfio_irq_set *irq_set;
 260         char irq_set_buf[IRQ_SET_BUF_LEN];
 261         int len, ret;
 262
 263         len = sizeof(struct vfio_irq_set);
 264
 265         irq_set = (struct vfio_irq_set *) irq_set_buf;
 266         irq_set->argsz = len;
 267         irq_set->count = 0;
 268         irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER;
 269         irq_set->index = VFIO_PCI_MSI_IRQ_INDEX;
 270         irq_set->start = 0;
 271
 272         ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
 273
 274         if (ret)
 275                 RTE_LOG(ERR, EAL,
 276                         "Error disabling MSI interrupts for fd %d\n", intr_handle->fd);
 277
 278         return ret;
 279 }
 280
 281 /* enable MSI-X interrupts */
 282 static int
 283 vfio_enable_msix(struct rte_intr_handle *intr_handle) {
 284         int len, ret;
 285         char irq_set_buf[MSIX_IRQ_SET_BUF_LEN];
 286         struct vfio_irq_set *irq_set;
 287         int *fd_ptr;
 288
 289         len = sizeof(irq_set_buf);
 290
 291         irq_set = (struct vfio_irq_set *) irq_set_buf;
 292         irq_set->argsz = len;
 293         if (!intr_handle->max_intr)
 294                 intr_handle->max_intr = 1;
 295         else if (intr_handle->max_intr > RTE_MAX_RXTX_INTR_VEC_ID)
 296                 intr_handle->max_intr = RTE_MAX_RXTX_INTR_VEC_ID + 1;
 297
 298         irq_set->count = intr_handle->max_intr;
 299         irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER;
 300         irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX;
 301         irq_set->start = 0;
 302         fd_ptr = (int *) &irq_set->data;
 303         /* INTR vector offset 0 reserve for non-efds mapping */
 304         fd_ptr[RTE_INTR_VEC_ZERO_OFFSET] = intr_handle->fd;
 305         memcpy(&fd_ptr[RTE_INTR_VEC_RXTX_OFFSET], intr_handle->efds,
 306                 sizeof(*intr_handle->efds) * intr_handle->nb_efd);
 307
 308         ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
 309
 310         if (ret) {
 311                 RTE_LOG(ERR, EAL, "Error enabling MSI-X interrupts for fd %d\n",
 312                                                 intr_handle->fd);
 313                 return -1;
 314         }
 315
 316         return 0;
 317 }
 318
 319 /* disable MSI-X interrupts */
 320 static int
 321 vfio_disable_msix(struct rte_intr_handle *intr_handle) {
 322         struct vfio_irq_set *irq_set;
 323         char irq_set_buf[MSIX_IRQ_SET_BUF_LEN];
 324         int len, ret;
 325
 326         len = sizeof(struct vfio_irq_set);
 327
 328         irq_set = (struct vfio_irq_set *) irq_set_buf;
 329         irq_set->argsz = len;
 330         irq_set->count = 0;
 331         irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER;
 332         irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX;
 333         irq_set->start = 0;
 334
 335         ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
 336
 337         if (ret)
 338                 RTE_LOG(ERR, EAL,
 339                         "Error disabling MSI-X interrupts for fd %d\n", intr_handle->fd);
 340
 341         return ret;
 342 }
 343 #endif
 344
 345 static int
 346 uio_intx_intr_disable(struct rte_intr_handle *intr_handle)
 347 {
 348         unsigned char command_high;
 349
 350         /* use UIO config file descriptor for uio_pci_generic */
 351         if (pread(intr_handle->uio_cfg_fd, &command_high, 1, 5) != 1) {
 352                 RTE_LOG(ERR, EAL,
 353                         "Error reading interrupts status for fd %d\n",
 354                         intr_handle->uio_cfg_fd);
 355                 return -1;
 356         }
 357         /* disable interrupts */
 358         command_high |= 0x4;
 359         if (pwrite(intr_handle->uio_cfg_fd, &command_high, 1, 5) != 1) {
 360                 RTE_LOG(ERR, EAL,
 361                         "Error disabling interrupts for fd %d\n",
 362                         intr_handle->uio_cfg_fd);
 363                 return -1;
 364         }
 365
 366         return 0;
 367 }
 368
 369 static int
 370 uio_intx_intr_enable(struct rte_intr_handle *intr_handle)
 371 {
 372         unsigned char command_high;
 373
 374         /* use UIO config file descriptor for uio_pci_generic */
 375         if (pread(intr_handle->uio_cfg_fd, &command_high, 1, 5) != 1) {
 376                 RTE_LOG(ERR, EAL,
 377                         "Error reading interrupts status for fd %d\n",
 378                         intr_handle->uio_cfg_fd);
 379                 return -1;
 380         }
 381         /* enable interrupts */
 382         command_high &= ~0x4;
 383         if (pwrite(intr_handle->uio_cfg_fd, &command_high, 1, 5) != 1) {
 384                 RTE_LOG(ERR, EAL,
 385                         "Error enabling interrupts for fd %d\n",
 386                         intr_handle->uio_cfg_fd);
 387                 return -1;
 388         }
 389
 390         return 0;
 391 }
 392
 393 static int
 394 uio_intr_disable(struct rte_intr_handle *intr_handle)
 395 {
 396         const int value = 0;
 397
 398         if (write(intr_handle->fd, &value, sizeof(value)) < 0) {
 399                 RTE_LOG(ERR, EAL,
 400                         "Error disabling interrupts for fd %d (%s)\n",
 401                         intr_handle->fd, strerror(errno));
 402                 return -1;
 403         }
 404         return 0;
 405 }
 406
 407 static int
 408 uio_intr_enable(struct rte_intr_handle *intr_handle)
 409 {
 410         const int value = 1;
 411
 412         if (write(intr_handle->fd, &value, sizeof(value)) < 0) {
 413                 RTE_LOG(ERR, EAL,
 414                         "Error enabling interrupts for fd %d (%s)\n",
 415                         intr_handle->fd, strerror(errno));
 416                 return -1;
 417         }
 418         return 0;
 419 }
 420
 421 int
 422 rte_intr_callback_register(struct rte_intr_handle *intr_handle,
 423                         rte_intr_callback_fn cb, void *cb_arg)
 424 {
 425         int ret, wake_thread;
 426         struct rte_intr_source *src;
 427         struct rte_intr_callback *callback;
 428
 429         wake_thread = 0;
 430
 431         /* first do parameter checking */
 432         if (intr_handle == NULL || intr_handle->fd < 0 || cb == NULL) {
 433                 RTE_LOG(ERR, EAL,
 434                         "Registering with invalid input parameter\n");
 435                 return -EINVAL;
 436         }
 437
 438         /* allocate a new interrupt callback entity */
 439         callback = rte_zmalloc("interrupt callback list",
 440                                 sizeof(*callback), 0);
 441         if (callback == NULL) {
 442                 RTE_LOG(ERR, EAL, "Can not allocate memory\n");
 443                 return -ENOMEM;
 444         }
 445         callback->cb_fn = cb;
 446         callback->cb_arg = cb_arg;
 447
 448         rte_spinlock_lock(&intr_lock);
 449
 450         /* check if there is at least one callback registered for the fd */
 451         TAILQ_FOREACH(src, &intr_sources, next) {
 452                 if (src->intr_handle.fd == intr_handle->fd) {
 453                         /* we had no interrupts for this */
 454                         if (TAILQ_EMPTY(&src->callbacks))
 455                                 wake_thread = 1;
 456
 457                         TAILQ_INSERT_TAIL(&(src->callbacks), callback, next);
 458                         ret = 0;
 459                         break;
 460                 }
 461         }
 462
 463         /* no existing callbacks for this - add new source */
 464         if (src == NULL) {
 465                 if ((src = rte_zmalloc("interrupt source list",
 466                                 sizeof(*src), 0)) == NULL) {
 467                         RTE_LOG(ERR, EAL, "Can not allocate memory\n");
 468                         rte_free(callback);
 469                         ret = -ENOMEM;
 470                 } else {
 471                         src->intr_handle = *intr_handle;
 472                         TAILQ_INIT(&src->callbacks);
 473                         TAILQ_INSERT_TAIL(&(src->callbacks), callback, next);
 474                         TAILQ_INSERT_TAIL(&intr_sources, src, next);
 475                         wake_thread = 1;
 476                         ret = 0;
 477                 }
 478         }
 479
 480         rte_spinlock_unlock(&intr_lock);
 481
 482         /**
 483          * check if need to notify the pipe fd waited by epoll_wait to
 484          * rebuild the wait list.
 485          */
 486         if (wake_thread)
 487                 if (write(intr_pipe.writefd, "1", 1) < 0)
 488                         return -EPIPE;
 489
 490         return ret;
 491 }
 492
 493 int
 494 rte_intr_callback_unregister(struct rte_intr_handle *intr_handle,
 495                         rte_intr_callback_fn cb_fn, void *cb_arg)
 496 {
 497         int ret;
 498         struct rte_intr_source *src;
 499         struct rte_intr_callback *cb, *next;
 500
 501         /* do parameter checking first */
 502         if (intr_handle == NULL || intr_handle->fd < 0) {
 503                 RTE_LOG(ERR, EAL,
 504                 "Unregistering with invalid input parameter\n");
 505                 return -EINVAL;
 506         }
 507
 508         rte_spinlock_lock(&intr_lock);
 509
 510         /* check if the insterrupt source for the fd is existent */
 511         TAILQ_FOREACH(src, &intr_sources, next)
 512                 if (src->intr_handle.fd == intr_handle->fd)
 513                         break;
 514
 515         /* No interrupt source registered for the fd */
 516         if (src == NULL) {
 517                 ret = -ENOENT;
 518
 519         /* interrupt source has some active callbacks right now. */
 520         } else if (src->active != 0) {
 521                 ret = -EAGAIN;
 522
 523         /* ok to remove. */
 524         } else {
 525                 ret = 0;
 526
 527                 /*walk through the callbacks and remove all that match. */
 528                 for (cb = TAILQ_FIRST(&src->callbacks); cb != NULL; cb = next) {
 529
 530                         next = TAILQ_NEXT(cb, next);
 531
 532                         if (cb->cb_fn == cb_fn && (cb_arg == (void *)-1 ||
 533                                         cb->cb_arg == cb_arg)) {
 534                                 TAILQ_REMOVE(&src->callbacks, cb, next);
 535                                 rte_free(cb);
 536                                 ret++;
 537                         }
 538                 }
 539
 540                 /* all callbacks for that source are removed. */
 541                 if (TAILQ_EMPTY(&src->callbacks)) {
 542                         TAILQ_REMOVE(&intr_sources, src, next);
 543                         rte_free(src);
 544                 }
 545         }
 546
 547         rte_spinlock_unlock(&intr_lock);
 548
 549         /* notify the pipe fd waited by epoll_wait to rebuild the wait list */
 550         if (ret >= 0 && write(intr_pipe.writefd, "1", 1) < 0) {
 551                 ret = -EPIPE;
 552         }
 553
 554         return ret;
 555 }
 556
 557 int
 558 rte_intr_enable(struct rte_intr_handle *intr_handle)
 559 {
 560         if (!intr_handle || intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0)
 561                 return -1;
 562
 563         switch (intr_handle->type){
 564         /* write to the uio fd to enable the interrupt */
 565         case RTE_INTR_HANDLE_UIO:
 566                 if (uio_intr_enable(intr_handle))
 567                         return -1;
 568                 break;
 569         case RTE_INTR_HANDLE_UIO_INTX:
 570                 if (uio_intx_intr_enable(intr_handle))
 571                         return -1;
 572                 break;
 573         /* not used at this moment */
 574         case RTE_INTR_HANDLE_ALARM:
 575                 return -1;
 576 #ifdef VFIO_PRESENT
 577         case RTE_INTR_HANDLE_VFIO_MSIX:
 578                 if (vfio_enable_msix(intr_handle))
 579                         return -1;
 580                 break;
 581         case RTE_INTR_HANDLE_VFIO_MSI:
 582                 if (vfio_enable_msi(intr_handle))
 583                         return -1;
 584                 break;
 585         case RTE_INTR_HANDLE_VFIO_LEGACY:
 586                 if (vfio_enable_intx(intr_handle))
 587                         return -1;
 588                 break;
 589 #endif
 590         /* unknown handle type */
 591         default:
 592                 RTE_LOG(ERR, EAL,
 593                         "Unknown handle type of fd %d\n",
 594                                         intr_handle->fd);
 595                 return -1;
 596         }
 597
 598         return 0;
 599 }
 600
 601 int
 602 rte_intr_disable(struct rte_intr_handle *intr_handle)
 603 {
 604         if (!intr_handle || intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0)
 605                 return -1;
 606
 607         switch (intr_handle->type){
 608         /* write to the uio fd to disable the interrupt */
 609         case RTE_INTR_HANDLE_UIO:
 610                 if (uio_intr_disable(intr_handle))
 611                         return -1;
 612                 break;
 613         case RTE_INTR_HANDLE_UIO_INTX:
 614                 if (uio_intx_intr_disable(intr_handle))
 615                         return -1;
 616                 break;
 617         /* not used at this moment */
 618         case RTE_INTR_HANDLE_ALARM:
 619                 return -1;
 620 #ifdef VFIO_PRESENT
 621         case RTE_INTR_HANDLE_VFIO_MSIX:
 622                 if (vfio_disable_msix(intr_handle))
 623                         return -1;
 624                 break;
 625         case RTE_INTR_HANDLE_VFIO_MSI:
 626                 if (vfio_disable_msi(intr_handle))
 627                         return -1;
 628                 break;
 629         case RTE_INTR_HANDLE_VFIO_LEGACY:
 630                 if (vfio_disable_intx(intr_handle))
 631                         return -1;
 632                 break;
 633 #endif
 634         /* unknown handle type */
 635         default:
 636                 RTE_LOG(ERR, EAL,
 637                         "Unknown handle type of fd %d\n",
 638                                         intr_handle->fd);
 639                 return -1;
 640         }
 641
 642         return 0;
 643 }
 644
 645 static int
 646 eal_intr_process_interrupts(struct epoll_event *events, int nfds)
 647 {
 648         int n, bytes_read;
 649         struct rte_intr_source *src;
 650         struct rte_intr_callback *cb, *next;
 651         union rte_intr_read_buffer buf;
 652         struct rte_intr_callback active_cb;
 653
 654         for (n = 0; n < nfds; n++) {
 655
 656                 /**
 657                  * if the pipe fd is ready to read, return out to
 658                  * rebuild the wait list.
 659                  */
 660                 if (events[n].data.fd == intr_pipe.readfd){
 661                         int r = read(intr_pipe.readfd, buf.charbuf,
 662                                         sizeof(buf.charbuf));
 663                         RTE_SET_USED(r);
 664                         return -1;
 665                 }
 666                 rte_spinlock_lock(&intr_lock);
 667                 TAILQ_FOREACH(src, &intr_sources, next)
 668                         if (src->intr_handle.fd ==
 669                                         events[n].data.fd)
 670                                 break;
 671                 if (src == NULL){
 672                         rte_spinlock_unlock(&intr_lock);
 673                         continue;
 674                 }
 675
 676                 /* mark this interrupt source as active and release the lock. */
 677                 src->active = 1;
 678                 rte_spinlock_unlock(&intr_lock);
 679
 680                 /* set the length to be read dor different handle type */
 681                 switch (src->intr_handle.type) {
 682                 case RTE_INTR_HANDLE_UIO:
 683                 case RTE_INTR_HANDLE_UIO_INTX:
 684                         bytes_read = sizeof(buf.uio_intr_count);
 685                         break;
 686                 case RTE_INTR_HANDLE_ALARM:
 687                         bytes_read = sizeof(buf.timerfd_num);
 688                         break;
 689 #ifdef VFIO_PRESENT
 690                 case RTE_INTR_HANDLE_VFIO_MSIX:
 691                 case RTE_INTR_HANDLE_VFIO_MSI:
 692                 case RTE_INTR_HANDLE_VFIO_LEGACY:
 693                         bytes_read = sizeof(buf.vfio_intr_count);
 694                         break;
 695 #endif
 696                 case RTE_INTR_HANDLE_EXT:
 697                 default:
 698                         bytes_read = 1;
 699                         break;
 700                 }
 701
 702                 if (src->intr_handle.type != RTE_INTR_HANDLE_EXT) {
 703                         /**
 704                          * read out to clear the ready-to-be-read flag
 705                          * for epoll_wait.
 706                          */
 707                         bytes_read = read(events[n].data.fd, &buf, bytes_read);
 708                         if (bytes_read < 0) {
 709                                 if (errno == EINTR || errno == EWOULDBLOCK)
 710                                         continue;
 711
 712                                 RTE_LOG(ERR, EAL, "Error reading from file "
 713                                         "descriptor %d: %s\n",
 714                                         events[n].data.fd,
 715                                         strerror(errno));
 716                                 /*
 717                                  * The device is unplugged or buggy, remove
 718                                  * it as an interrupt source and return to
 719                                  * force the wait list to be rebuilt.
 720                                  */
 721                                 rte_spinlock_lock(&intr_lock);
 722                                 TAILQ_REMOVE(&intr_sources, src, next);
 723                                 rte_spinlock_unlock(&intr_lock);
 724
 725                                 for (cb = TAILQ_FIRST(&src->callbacks); cb;
 726                                                         cb = next) {
 727                                         next = TAILQ_NEXT(cb, next);
 728                                         TAILQ_REMOVE(&src->callbacks, cb, next);
 729                                         free(cb);
 730                                 }
 731                                 free(src);
 732                                 return -1;
 733                         } else if (bytes_read == 0)
 734                                 RTE_LOG(ERR, EAL, "Read nothing from file "
 735                                         "descriptor %d\n", events[n].data.fd);
 736                 }
 737
 738                 /* grab a lock, again to call callbacks and update status. */
 739                 rte_spinlock_lock(&intr_lock);
 740
 741                 if (bytes_read > 0) {
 742
 743                         /* Finally, call all callbacks. */
 744                         TAILQ_FOREACH(cb, &src->callbacks, next) {
 745
 746                                 /* make a copy and unlock. */
 747                                 active_cb = *cb;
 748                                 rte_spinlock_unlock(&intr_lock);
 749
 750                                 /* call the actual callback */
 751                                 active_cb.cb_fn(&src->intr_handle,
 752                                         active_cb.cb_arg);
 753
 754                                 /*get the lock back. */
 755                                 rte_spinlock_lock(&intr_lock);
 756                         }
 757                 }
 758
 759                 /* we done with that interrupt source, release it. */
 760                 src->active = 0;
 761                 rte_spinlock_unlock(&intr_lock);
 762         }
 763
 764         return 0;
 765 }
 766
 767 /**
 768  * It handles all the interrupts.
 769  *
 770  * @param pfd
 771  *  epoll file descriptor.
 772  * @param totalfds
 773  *  The number of file descriptors added in epoll.
 774  *
 775  * @return
 776  *  void
 777  */
 778 static void
 779 eal_intr_handle_interrupts(int pfd, unsigned totalfds)
 780 {
 781         struct epoll_event events[totalfds];
 782         int nfds = 0;
 783
 784         for(;;) {
 785                 nfds = epoll_wait(pfd, events, totalfds,
 786                         EAL_INTR_EPOLL_WAIT_FOREVER);
 787                 /* epoll_wait fail */
 788                 if (nfds < 0) {
 789                         if (errno == EINTR)
 790                                 continue;
 791                         RTE_LOG(ERR, EAL,
 792                                 "epoll_wait returns with fail\n");
 793                         return;
 794                 }
 795                 /* epoll_wait timeout, will never happens here */
 796                 else if (nfds == 0)
 797                         continue;
 798                 /* epoll_wait has at least one fd ready to read */
 799                 if (eal_intr_process_interrupts(events, nfds) < 0)
 800                         return;
 801         }
 802 }
 803
 804 /**
 805  * It builds/rebuilds up the epoll file descriptor with all the
 806  * file descriptors being waited on. Then handles the interrupts.
 807  *
 808  * @param arg
 809  *  pointer. (unused)
 810  *
 811  * @return
 812  *  never return;
 813  */
 814 static __attribute__((noreturn)) void *
 815 eal_intr_thread_main(__rte_unused void *arg)
 816 {
 817         struct epoll_event ev;
 818
 819         /* host thread, never break out */
 820         for (;;) {
 821                 /* build up the epoll fd with all descriptors we are to
 822                  * wait on then pass it to the handle_interrupts function
 823                  */
 824                 static struct epoll_event pipe_event = {
 825                         .events = EPOLLIN | EPOLLPRI,
 826                 };
 827                 struct rte_intr_source *src;
 828                 unsigned numfds = 0;
 829
 830                 /* create epoll fd */
 831                 int pfd = epoll_create(1);
 832                 if (pfd < 0)
 833                         rte_panic("Cannot create epoll instance\n");
 834
 835                 pipe_event.data.fd = intr_pipe.readfd;
 836                 /**
 837                  * add pipe fd into wait list, this pipe is used to
 838                  * rebuild the wait list.
 839                  */
 840                 if (epoll_ctl(pfd, EPOLL_CTL_ADD, intr_pipe.readfd,
 841                                                 &pipe_event) < 0) {
 842                         rte_panic("Error adding fd to %d epoll_ctl, %s\n",
 843                                         intr_pipe.readfd, strerror(errno));
 844                 }
 845                 numfds++;
 846
 847                 rte_spinlock_lock(&intr_lock);
 848
 849                 TAILQ_FOREACH(src, &intr_sources, next) {
 850                         if (src->callbacks.tqh_first == NULL)
 851                                 continue; /* skip those with no callbacks */
 852                         ev.events = EPOLLIN | EPOLLPRI;
 853                         ev.data.fd = src->intr_handle.fd;
 854
 855                         /**
 856                          * add all the uio device file descriptor
 857                          * into wait list.
 858                          */
 859                         if (epoll_ctl(pfd, EPOLL_CTL_ADD,
 860                                         src->intr_handle.fd, &ev) < 0){
 861                                 rte_panic("Error adding fd %d epoll_ctl, %s\n",
 862                                         src->intr_handle.fd, strerror(errno));
 863                         }
 864                         else
 865                                 numfds++;
 866                 }
 867                 rte_spinlock_unlock(&intr_lock);
 868                 /* serve the interrupt */
 869                 eal_intr_handle_interrupts(pfd, numfds);
 870
 871                 /**
 872                  * when we return, we need to rebuild the
 873                  * list of fds to monitor.
 874                  */
 875                 close(pfd);
 876         }
 877 }
 878
 879 int
 880 rte_eal_intr_init(void)
 881 {
 882         int ret = 0, ret_1 = 0;
 883         char thread_name[RTE_MAX_THREAD_NAME_LEN];
 884
 885         /* init the global interrupt source head */
 886         TAILQ_INIT(&intr_sources);
 887
 888         /**
 889          * create a pipe which will be waited by epoll and notified to
 890          * rebuild the wait list of epoll.
 891          */
 892         if (pipe(intr_pipe.pipefd) < 0)
 893                 return -1;
 894
 895         /* create the host thread to wait/handle the interrupt */
 896         ret = pthread_create(&intr_thread, NULL,
 897                         eal_intr_thread_main, NULL);
 898         if (ret != 0) {
 899                 RTE_LOG(ERR, EAL,
 900                         "Failed to create thread for interrupt handling\n");
 901         } else {
 902                 /* Set thread_name for aid in debugging. */
 903                 snprintf(thread_name, RTE_MAX_THREAD_NAME_LEN,
 904                         "eal-intr-thread");
 905                 ret_1 = rte_thread_setname(intr_thread, thread_name);
 906                 if (ret_1 != 0)
 907                         RTE_LOG(DEBUG, EAL,
 908                         "Failed to set thread name for interrupt handling\n");
 909         }
 910
 911         return -ret;
 912 }
 913
 914 static void
 915 eal_intr_proc_rxtx_intr(int fd, const struct rte_intr_handle *intr_handle)
 916 {
 917         union rte_intr_read_buffer buf;
 918         int bytes_read = 1;
 919         int nbytes;
 920
 921         switch (intr_handle->type) {
 922         case RTE_INTR_HANDLE_UIO:
 923         case RTE_INTR_HANDLE_UIO_INTX:
 924                 bytes_read = sizeof(buf.uio_intr_count);
 925                 break;
 926 #ifdef VFIO_PRESENT
 927         case RTE_INTR_HANDLE_VFIO_MSIX:
 928         case RTE_INTR_HANDLE_VFIO_MSI:
 929         case RTE_INTR_HANDLE_VFIO_LEGACY:
 930                 bytes_read = sizeof(buf.vfio_intr_count);
 931                 break;
 932 #endif
 933         default:
 934                 bytes_read = 1;
 935                 RTE_LOG(INFO, EAL, "unexpected intr type\n");
 936                 break;
 937         }
 938
 939         /**
 940          * read out to clear the ready-to-be-read flag
 941          * for epoll_wait.
 942          */
 943         do {
 944                 nbytes = read(fd, &buf, bytes_read);
 945                 if (nbytes < 0) {
 946                         if (errno == EINTR || errno == EWOULDBLOCK ||
 947                             errno == EAGAIN)
 948                                 continue;
 949                         RTE_LOG(ERR, EAL,
 950                                 "Error reading from fd %d: %s\n",
 951                                 fd, strerror(errno));
 952                 } else if (nbytes == 0)
 953                         RTE_LOG(ERR, EAL, "Read nothing from fd %d\n", fd);
 954                 return;
 955         } while (1);
 956 }
 957
 958 static int
 959 eal_epoll_process_event(struct epoll_event *evs, unsigned int n,
 960                         struct rte_epoll_event *events)
 961 {
 962         unsigned int i, count = 0;
 963         struct rte_epoll_event *rev;
 964
 965         for (i = 0; i < n; i++) {
 966                 rev = evs[i].data.ptr;
 967                 if (!rev || !rte_atomic32_cmpset(&rev->status, RTE_EPOLL_VALID,
 968                                                  RTE_EPOLL_EXEC))
 969                         continue;
 970
 971                 events[count].status        = RTE_EPOLL_VALID;
 972                 events[count].fd            = rev->fd;
 973                 events[count].epfd          = rev->epfd;
 974                 events[count].epdata.event  = rev->epdata.event;
 975                 events[count].epdata.data   = rev->epdata.data;
 976                 if (rev->epdata.cb_fun)
 977                         rev->epdata.cb_fun(rev->fd,
 978                                            rev->epdata.cb_arg);
 979
 980                 rte_compiler_barrier();
 981                 rev->status = RTE_EPOLL_VALID;
 982                 count++;
 983         }
 984         return count;
 985 }
 986
 987 static inline int
 988 eal_init_tls_epfd(void)
 989 {
 990         int pfd = epoll_create(255);
 991
 992         if (pfd < 0) {
 993                 RTE_LOG(ERR, EAL,
 994                         "Cannot create epoll instance\n");
 995                 return -1;
 996         }
 997         return pfd;
 998 }
 999
1000 int
1001 rte_intr_tls_epfd(void)
1002 {
1003         if (RTE_PER_LCORE(_epfd) == -1)
1004                 RTE_PER_LCORE(_epfd) = eal_init_tls_epfd();
1005
1006         return RTE_PER_LCORE(_epfd);
1007 }
1008
1009 int
1010 rte_epoll_wait(int epfd, struct rte_epoll_event *events,
1011                int maxevents, int timeout)
1012 {
1013         struct epoll_event evs[maxevents];
1014         int rc;
1015
1016         if (!events) {
1017                 RTE_LOG(ERR, EAL, "rte_epoll_event can't be NULL\n");
1018                 return -1;
1019         }
1020
1021         /* using per thread epoll fd */
1022         if (epfd == RTE_EPOLL_PER_THREAD)
1023                 epfd = rte_intr_tls_epfd();
1024
1025         while (1) {
1026                 rc = epoll_wait(epfd, evs, maxevents, timeout);
1027                 if (likely(rc > 0)) {
1028                         /* epoll_wait has at least one fd ready to read */
1029                         rc = eal_epoll_process_event(evs, rc, events);
1030                         break;
1031                 } else if (rc < 0) {
1032                         if (errno == EINTR)
1033                                 continue;
1034                         /* epoll_wait fail */
1035                         RTE_LOG(ERR, EAL, "epoll_wait returns with fail %s\n",
1036                                 strerror(errno));
1037                         rc = -1;
1038                         break;
1039                 } else {
1040                         /* rc == 0, epoll_wait timed out */
1041                         break;
1042                 }
1043         }
1044
1045         return rc;
1046 }
1047
1048 static inline void
1049 eal_epoll_data_safe_free(struct rte_epoll_event *ev)
1050 {
1051         while (!rte_atomic32_cmpset(&ev->status, RTE_EPOLL_VALID,
1052                                     RTE_EPOLL_INVALID))
1053                 while (ev->status != RTE_EPOLL_VALID)
1054                         rte_pause();
1055         memset(&ev->epdata, 0, sizeof(ev->epdata));
1056         ev->fd = -1;
1057         ev->epfd = -1;
1058 }
1059
1060 int
1061 rte_epoll_ctl(int epfd, int op, int fd,
1062               struct rte_epoll_event *event)
1063 {
1064         struct epoll_event ev;
1065
1066         if (!event) {
1067                 RTE_LOG(ERR, EAL, "rte_epoll_event can't be NULL\n");
1068                 return -1;
1069         }
1070
1071         /* using per thread epoll fd */
1072         if (epfd == RTE_EPOLL_PER_THREAD)
1073                 epfd = rte_intr_tls_epfd();
1074
1075         if (op == EPOLL_CTL_ADD) {
1076                 event->status = RTE_EPOLL_VALID;
1077                 event->fd = fd;  /* ignore fd in event */
1078                 event->epfd = epfd;
1079                 ev.data.ptr = (void *)event;
1080         }
1081
1082         ev.events = event->epdata.event;
1083         if (epoll_ctl(epfd, op, fd, &ev) < 0) {
1084                 RTE_LOG(ERR, EAL, "Error op %d fd %d epoll_ctl, %s\n",
1085                         op, fd, strerror(errno));
1086                 if (op == EPOLL_CTL_ADD)
1087                         /* rollback status when CTL_ADD fail */
1088                         event->status = RTE_EPOLL_INVALID;
1089                 return -1;
1090         }
1091
1092         if (op == EPOLL_CTL_DEL && event->status != RTE_EPOLL_INVALID)
1093                 eal_epoll_data_safe_free(event);
1094
1095         return 0;
1096 }
1097
1098 int
1099 rte_intr_rx_ctl(struct rte_intr_handle *intr_handle, int epfd,
1100                 int op, unsigned int vec, void *data)
1101 {
1102         struct rte_epoll_event *rev;
1103         struct rte_epoll_data *epdata;
1104         int epfd_op;
1105         unsigned int efd_idx;
1106         int rc = 0;
1107
1108         efd_idx = (vec >= RTE_INTR_VEC_RXTX_OFFSET) ?
1109                 (vec - RTE_INTR_VEC_RXTX_OFFSET) : vec;
1110
1111         if (!intr_handle || intr_handle->nb_efd == 0 ||
1112             efd_idx >= intr_handle->nb_efd) {
1113                 RTE_LOG(ERR, EAL, "Wrong intr vector number.\n");
1114                 return -EPERM;
1115         }
1116
1117         switch (op) {
1118         case RTE_INTR_EVENT_ADD:
1119                 epfd_op = EPOLL_CTL_ADD;
1120                 rev = &intr_handle->elist[efd_idx];
1121                 if (rev->status != RTE_EPOLL_INVALID) {
1122                         RTE_LOG(INFO, EAL, "Event already been added.\n");
1123                         return -EEXIST;
1124                 }
1125
1126                 /* attach to intr vector fd */
1127                 epdata = &rev->epdata;
1128                 epdata->event  = EPOLLIN | EPOLLPRI | EPOLLET;
1129                 epdata->data   = data;
1130                 epdata->cb_fun = (rte_intr_event_cb_t)eal_intr_proc_rxtx_intr;
1131                 epdata->cb_arg = (void *)intr_handle;
1132                 rc = rte_epoll_ctl(epfd, epfd_op,
1133                                    intr_handle->efds[efd_idx], rev);
1134                 if (!rc)
1135                         RTE_LOG(DEBUG, EAL,
1136                                 "efd %d associated with vec %d added on epfd %d"
1137                                 "\n", rev->fd, vec, epfd);
1138                 else
1139                         rc = -EPERM;
1140                 break;
1141         case RTE_INTR_EVENT_DEL:
1142                 epfd_op = EPOLL_CTL_DEL;
1143                 rev = &intr_handle->elist[efd_idx];
1144                 if (rev->status == RTE_EPOLL_INVALID) {
1145                         RTE_LOG(INFO, EAL, "Event does not exist.\n");
1146                         return -EPERM;
1147                 }
1148
1149                 rc = rte_epoll_ctl(rev->epfd, epfd_op, rev->fd, rev);
1150                 if (rc)
1151                         rc = -EPERM;
1152                 break;
1153         default:
1154                 RTE_LOG(ERR, EAL, "event op type mismatch\n");
1155                 rc = -EPERM;
1156         }
1157
1158         return rc;
1159 }
1160
1161 int
1162 rte_intr_efd_enable(struct rte_intr_handle *intr_handle, uint32_t nb_efd)
1163 {
1164         uint32_t i;
1165         int fd;
1166         uint32_t n = RTE_MIN(nb_efd, (uint32_t)RTE_MAX_RXTX_INTR_VEC_ID);
1167
1168         assert(nb_efd != 0);
1169
1170         if (intr_handle->type == RTE_INTR_HANDLE_VFIO_MSIX) {
1171                 for (i = 0; i < n; i++) {
1172                         fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
1173                         if (fd < 0) {
1174                                 RTE_LOG(ERR, EAL,
1175                                         "can't setup eventfd, error %i (%s)\n",
1176                                         errno, strerror(errno));
1177                                 return -1;
1178                         }
1179                         intr_handle->efds[i] = fd;
1180                 }
1181                 intr_handle->nb_efd   = n;
1182                 intr_handle->max_intr = NB_OTHER_INTR + n;
1183         } else {
1184                 intr_handle->efds[0]  = intr_handle->fd;
1185                 intr_handle->nb_efd   = RTE_MIN(nb_efd, 1U);
1186                 intr_handle->max_intr = NB_OTHER_INTR;
1187         }
1188
1189         return 0;
1190 }
1191
1192 void
1193 rte_intr_efd_disable(struct rte_intr_handle *intr_handle)
1194 {
1195         uint32_t i;
1196         struct rte_epoll_event *rev;
1197
1198         for (i = 0; i < intr_handle->nb_efd; i++) {
1199                 rev = &intr_handle->elist[i];
1200                 if (rev->status == RTE_EPOLL_INVALID)
1201                         continue;
1202                 if (rte_epoll_ctl(rev->epfd, EPOLL_CTL_DEL, rev->fd, rev)) {
1203                         /* force free if the entry valid */
1204                         eal_epoll_data_safe_free(rev);
1205                         rev->status = RTE_EPOLL_INVALID;
1206                 }
1207         }
1208
1209         if (intr_handle->max_intr > intr_handle->nb_efd) {
1210                 for (i = 0; i < intr_handle->nb_efd; i++)
1211                         close(intr_handle->efds[i]);
1212         }
1213         intr_handle->nb_efd = 0;
1214         intr_handle->max_intr = 0;
1215 }
1216
1217 int
1218 rte_intr_dp_is_en(struct rte_intr_handle *intr_handle)
1219 {
1220         return !(!intr_handle->nb_efd);
1221 }
1222
1223 int
1224 rte_intr_allow_others(struct rte_intr_handle *intr_handle)
1225 {
1226         if (!rte_intr_dp_is_en(intr_handle))
1227                 return 1;
1228         else
1229                 return !!(intr_handle->max_intr - intr_handle->nb_efd);
1230 }
1231
1232 int
1233 rte_intr_cap_multiple(struct rte_intr_handle *intr_handle)
1234 {
1235         if (intr_handle->type == RTE_INTR_HANDLE_VFIO_MSIX)
1236                 return 1;
1237
1238         return 0;
1239 }