root/drivers/soc/fsl/qbman/qman_test_stash.c

DEFINITIONS

1. bstrap_fn
2. on_all_cpus
3. do_lfsr
4. allocate_frame_data
5. deallocate_frame_data
6. process_frame_data
7. normal_dqrr
8. special_dqrr
9. create_per_cpu_handlers
10. destroy_per_cpu_handlers
11. num_cachelines
12. init_handler
13. init_handler_cb
14. init_phase2
15. init_phase3
16. send_first_frame
17. send_first_frame_cb
18. qman_test_stash

   1 /* Copyright 2009 - 2016 Freescale Semiconductor, Inc.
   2  *
   3  * Redistribution and use in source and binary forms, with or without
   4  * modification, are permitted provided that the following conditions are met:
   5  *     * Redistributions of source code must retain the above copyright
   6  *       notice, this list of conditions and the following disclaimer.
   7  *     * Redistributions in binary form must reproduce the above copyright
   8  *       notice, this list of conditions and the following disclaimer in the
   9  *       documentation and/or other materials provided with the distribution.
  10  *     * Neither the name of Freescale Semiconductor nor the
  11  *       names of its contributors may be used to endorse or promote products
  12  *       derived from this software without specific prior written permission.
  13  *
  14  * ALTERNATIVELY, this software may be distributed under the terms of the
  15  * GNU General Public License ("GPL") as published by the Free Software
  16  * Foundation, either version 2 of that License or (at your option) any
  17  * later version.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY Freescale Semiconductor ``AS IS'' AND ANY
  20  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  21  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  22  * DISCLAIMED. IN NO EVENT SHALL Freescale Semiconductor BE LIABLE FOR ANY
  23  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  25  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  26  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  28  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30 
  31 #include "qman_test.h"
  32 
  33 #include <linux/dma-mapping.h>
  34 #include <linux/delay.h>
  35 
  36 /*
  37  * Algorithm:
  38  *
  39  * Each cpu will have HP_PER_CPU "handlers" set up, each of which incorporates
  40  * an rx/tx pair of FQ objects (both of which are stashed on dequeue). The
  41  * organisation of FQIDs is such that the HP_PER_CPU*NUM_CPUS handlers will
  42  * shuttle a "hot potato" frame around them such that every forwarding action
  43  * moves it from one cpu to another. (The use of more than one handler per cpu
  44  * is to allow enough handlers/FQs to truly test the significance of caching -
  45  * ie. when cache-expiries are occurring.)
  46  *
  47  * The "hot potato" frame content will be HP_NUM_WORDS*4 bytes in size, and the
  48  * first and last words of the frame data will undergo a transformation step on
  49  * each forwarding action. To achieve this, each handler will be assigned a
  50  * 32-bit "mixer", that is produced using a 32-bit LFSR. When a frame is
  51  * received by a handler, the mixer of the expected sender is XOR'd into all
  52  * words of the entire frame, which is then validated against the original
  53  * values. Then, before forwarding, the entire frame is XOR'd with the mixer of
  54  * the current handler. Apart from validating that the frame is taking the
  55  * expected path, this also provides some quasi-realistic overheads to each
  56  * forwarding action - dereferencing *all* the frame data, computation, and
  57  * conditional branching. There is a "special" handler designated to act as the
  58  * instigator of the test by creating an enqueuing the "hot potato" frame, and
  59  * to determine when the test has completed by counting HP_LOOPS iterations.
  60  *
  61  * Init phases:
  62  *
  63  * 1. prepare each cpu's 'hp_cpu' struct using on_each_cpu(,,1) and link them
  64  *    into 'hp_cpu_list'. Specifically, set processor_id, allocate HP_PER_CPU
  65  *    handlers and link-list them (but do no other handler setup).
  66  *
  67  * 2. scan over 'hp_cpu_list' HP_PER_CPU times, the first time sets each
  68  *    hp_cpu's 'iterator' to point to its first handler. With each loop,
  69  *    allocate rx/tx FQIDs and mixer values to the hp_cpu's iterator handler
  70  *    and advance the iterator for the next loop. This includes a final fixup,
  71  *    which connects the last handler to the first (and which is why phase 2
  72  *    and 3 are separate).
  73  *
  74  * 3. scan over 'hp_cpu_list' HP_PER_CPU times, the first time sets each
  75  *    hp_cpu's 'iterator' to point to its first handler. With each loop,
  76  *    initialise FQ objects and advance the iterator for the next loop.
  77  *    Moreover, do this initialisation on the cpu it applies to so that Rx FQ
  78  *    initialisation targets the correct cpu.
  79  */
  80 
  81 /*
  82  * helper to run something on all cpus (can't use on_each_cpu(), as that invokes
  83  * the fn from irq context, which is too restrictive).
  84  */
  85 struct bstrap {
  86         int (*fn)(void);
  87         atomic_t started;
  88 };
  89 static int bstrap_fn(void *bs)
  90 {
  91         struct bstrap *bstrap = bs;
  92         int err;
  93 
  94         atomic_inc(&bstrap->started);
  95         err = bstrap->fn();
  96         if (err)
  97                 return err;
  98         while (!kthread_should_stop())
  99                 msleep(20);
 100         return 0;
 101 }
 102 static int on_all_cpus(int (*fn)(void))
 103 {
 104         int cpu;
 105 
 106         for_each_cpu(cpu, cpu_online_mask) {
 107                 struct bstrap bstrap = {
 108                         .fn = fn,
 109                         .started = ATOMIC_INIT(0)
 110                 };
 111                 struct task_struct *k = kthread_create(bstrap_fn, &bstrap,
 112                         "hotpotato%d", cpu);
 113                 int ret;
 114 
 115                 if (IS_ERR(k))
 116                         return -ENOMEM;
 117                 kthread_bind(k, cpu);
 118                 wake_up_process(k);
 119                 /*
 120                  * If we call kthread_stop() before the "wake up" has had an
 121                  * effect, then the thread may exit with -EINTR without ever
 122                  * running the function. So poll until it's started before
 123                  * requesting it to stop.
 124                  */
 125                 while (!atomic_read(&bstrap.started))
 126                         msleep(20);
 127                 ret = kthread_stop(k);
 128                 if (ret)
 129                         return ret;
 130         }
 131         return 0;
 132 }
 133 
 134 struct hp_handler {
 135 
 136         /* The following data is stashed when 'rx' is dequeued; */
 137         /* -------------- */
 138         /* The Rx FQ, dequeues of which will stash the entire hp_handler */
 139         struct qman_fq rx;
 140         /* The Tx FQ we should forward to */
 141         struct qman_fq tx;
 142         /* The value we XOR post-dequeue, prior to validating */
 143         u32 rx_mixer;
 144         /* The value we XOR pre-enqueue, after validating */
 145         u32 tx_mixer;
 146         /* what the hotpotato address should be on dequeue */
 147         dma_addr_t addr;
 148         u32 *frame_ptr;
 149 
 150         /* The following data isn't (necessarily) stashed on dequeue; */
 151         /* -------------- */
 152         u32 fqid_rx, fqid_tx;
 153         /* list node for linking us into 'hp_cpu' */
 154         struct list_head node;
 155         /* Just to check ... */
 156         unsigned int processor_id;
 157 } ____cacheline_aligned;
 158 
 159 struct hp_cpu {
 160         /* identify the cpu we run on; */
 161         unsigned int processor_id;
 162         /* root node for the per-cpu list of handlers */
 163         struct list_head handlers;
 164         /* list node for linking us into 'hp_cpu_list' */
 165         struct list_head node;
 166         /*
 167          * when repeatedly scanning 'hp_list', each time linking the n'th
 168          * handlers together, this is used as per-cpu iterator state
 169          */
 170         struct hp_handler *iterator;
 171 };
 172 
 173 /* Each cpu has one of these */
 174 static DEFINE_PER_CPU(struct hp_cpu, hp_cpus);
 175 
 176 /* links together the hp_cpu structs, in first-come first-serve order. */
 177 static LIST_HEAD(hp_cpu_list);
 178 static DEFINE_SPINLOCK(hp_lock);
 179 
 180 static unsigned int hp_cpu_list_length;
 181 
 182 /* the "special" handler, that starts and terminates the test. */
 183 static struct hp_handler *special_handler;
 184 static int loop_counter;
 185 
 186 /* handlers are allocated out of this, so they're properly aligned. */
 187 static struct kmem_cache *hp_handler_slab;
 188 
 189 /* this is the frame data */
 190 static void *__frame_ptr;
 191 static u32 *frame_ptr;
 192 static dma_addr_t frame_dma;
 193 
 194 /* needed for dma_map*() */
 195 static const struct qm_portal_config *pcfg;
 196 
 197 /* the main function waits on this */
 198 static DECLARE_WAIT_QUEUE_HEAD(queue);
 199 
 200 #define HP_PER_CPU      2
 201 #define HP_LOOPS        8
 202 /* 80 bytes, like a small ethernet frame, and bleeds into a second cacheline */
 203 #define HP_NUM_WORDS    80
 204 /* First word of the LFSR-based frame data */
 205 #define HP_FIRST_WORD   0xabbaf00d
 206 
 207 static inline u32 do_lfsr(u32 prev)
 208 {
 209         return (prev >> 1) ^ (-(prev & 1u) & 0xd0000001u);
 210 }
 211 
 212 static int allocate_frame_data(void)
 213 {
 214         u32 lfsr = HP_FIRST_WORD;
 215         int loop;
 216 
 217         if (!qman_dma_portal) {
 218                 pr_crit("portal not available\n");
 219                 return -EIO;
 220         }
 221 
 222         pcfg = qman_get_qm_portal_config(qman_dma_portal);
 223 
 224         __frame_ptr = kmalloc(4 * HP_NUM_WORDS, GFP_KERNEL);
 225         if (!__frame_ptr)
 226                 return -ENOMEM;
 227 
 228         frame_ptr = PTR_ALIGN(__frame_ptr, 64);
 229         for (loop = 0; loop < HP_NUM_WORDS; loop++) {
 230                 frame_ptr[loop] = lfsr;
 231                 lfsr = do_lfsr(lfsr);
 232         }
 233 
 234         frame_dma = dma_map_single(pcfg->dev, frame_ptr, 4 * HP_NUM_WORDS,
 235                                    DMA_BIDIRECTIONAL);
 236         if (dma_mapping_error(pcfg->dev, frame_dma)) {
 237                 pr_crit("dma mapping failure\n");
 238                 kfree(__frame_ptr);
 239                 return -EIO;
 240         }
 241 
 242         return 0;
 243 }
 244 
 245 static void deallocate_frame_data(void)
 246 {
 247         dma_unmap_single(pcfg->dev, frame_dma, 4 * HP_NUM_WORDS,
 248                          DMA_BIDIRECTIONAL);
 249         kfree(__frame_ptr);
 250 }
 251 
 252 static inline int process_frame_data(struct hp_handler *handler,
 253                                      const struct qm_fd *fd)
 254 {
 255         u32 *p = handler->frame_ptr;
 256         u32 lfsr = HP_FIRST_WORD;
 257         int loop;
 258 
 259         if (qm_fd_addr_get64(fd) != handler->addr) {
 260                 pr_crit("bad frame address, [%llX != %llX]\n",
 261                         qm_fd_addr_get64(fd), handler->addr);
 262                 return -EIO;
 263         }
 264         for (loop = 0; loop < HP_NUM_WORDS; loop++, p++) {
 265                 *p ^= handler->rx_mixer;
 266                 if (*p != lfsr) {
 267                         pr_crit("corrupt frame data");
 268                         return -EIO;
 269                 }
 270                 *p ^= handler->tx_mixer;
 271                 lfsr = do_lfsr(lfsr);
 272         }
 273         return 0;
 274 }
 275 
 276 static enum qman_cb_dqrr_result normal_dqrr(struct qman_portal *portal,
 277                                             struct qman_fq *fq,
 278                                             const struct qm_dqrr_entry *dqrr)
 279 {
 280         struct hp_handler *handler = (struct hp_handler *)fq;
 281 
 282         if (process_frame_data(handler, &dqrr->fd)) {
 283                 WARN_ON(1);
 284                 goto skip;
 285         }
 286         if (qman_enqueue(&handler->tx, &dqrr->fd)) {
 287                 pr_crit("qman_enqueue() failed");
 288                 WARN_ON(1);
 289         }
 290 skip:
 291         return qman_cb_dqrr_consume;
 292 }
 293 
 294 static enum qman_cb_dqrr_result special_dqrr(struct qman_portal *portal,
 295                                              struct qman_fq *fq,
 296                                              const struct qm_dqrr_entry *dqrr)
 297 {
 298         struct hp_handler *handler = (struct hp_handler *)fq;
 299 
 300         process_frame_data(handler, &dqrr->fd);
 301         if (++loop_counter < HP_LOOPS) {
 302                 if (qman_enqueue(&handler->tx, &dqrr->fd)) {
 303                         pr_crit("qman_enqueue() failed");
 304                         WARN_ON(1);
 305                         goto skip;
 306                 }
 307         } else {
 308                 pr_info("Received final (%dth) frame\n", loop_counter);
 309                 wake_up(&queue);
 310         }
 311 skip:
 312         return qman_cb_dqrr_consume;
 313 }
 314 
 315 static int create_per_cpu_handlers(void)
 316 {
 317         struct hp_handler *handler;
 318         int loop;
 319         struct hp_cpu *hp_cpu = this_cpu_ptr(&hp_cpus);
 320 
 321         hp_cpu->processor_id = smp_processor_id();
 322         spin_lock(&hp_lock);
 323         list_add_tail(&hp_cpu->node, &hp_cpu_list);
 324         hp_cpu_list_length++;
 325         spin_unlock(&hp_lock);
 326         INIT_LIST_HEAD(&hp_cpu->handlers);
 327         for (loop = 0; loop < HP_PER_CPU; loop++) {
 328                 handler = kmem_cache_alloc(hp_handler_slab, GFP_KERNEL);
 329                 if (!handler) {
 330                         pr_crit("kmem_cache_alloc() failed");
 331                         WARN_ON(1);
 332                         return -EIO;
 333                 }
 334                 handler->processor_id = hp_cpu->processor_id;
 335                 handler->addr = frame_dma;
 336                 handler->frame_ptr = frame_ptr;
 337                 list_add_tail(&handler->node, &hp_cpu->handlers);
 338         }
 339         return 0;
 340 }
 341 
 342 static int destroy_per_cpu_handlers(void)
 343 {
 344         struct list_head *loop, *tmp;
 345         struct hp_cpu *hp_cpu = this_cpu_ptr(&hp_cpus);
 346 
 347         spin_lock(&hp_lock);
 348         list_del(&hp_cpu->node);
 349         spin_unlock(&hp_lock);
 350         list_for_each_safe(loop, tmp, &hp_cpu->handlers) {
 351                 u32 flags = 0;
 352                 struct hp_handler *handler = list_entry(loop, struct hp_handler,
 353                                                         node);
 354                 if (qman_retire_fq(&handler->rx, &flags) ||
 355                     (flags & QMAN_FQ_STATE_BLOCKOOS)) {
 356                         pr_crit("qman_retire_fq(rx) failed, flags: %x", flags);
 357                         WARN_ON(1);
 358                         return -EIO;
 359                 }
 360                 if (qman_oos_fq(&handler->rx)) {
 361                         pr_crit("qman_oos_fq(rx) failed");
 362                         WARN_ON(1);
 363                         return -EIO;
 364                 }
 365                 qman_destroy_fq(&handler->rx);
 366                 qman_destroy_fq(&handler->tx);
 367                 qman_release_fqid(handler->fqid_rx);
 368                 list_del(&handler->node);
 369                 kmem_cache_free(hp_handler_slab, handler);
 370         }
 371         return 0;
 372 }
 373 
 374 static inline u8 num_cachelines(u32 offset)
 375 {
 376         u8 res = (offset + (L1_CACHE_BYTES - 1))
 377                          / (L1_CACHE_BYTES);
 378         if (res > 3)
 379                 return 3;
 380         return res;
 381 }
 382 #define STASH_DATA_CL \
 383         num_cachelines(HP_NUM_WORDS * 4)
 384 #define STASH_CTX_CL \
 385         num_cachelines(offsetof(struct hp_handler, fqid_rx))
 386 
 387 static int init_handler(void *h)
 388 {
 389         struct qm_mcc_initfq opts;
 390         struct hp_handler *handler = h;
 391         int err;
 392 
 393         if (handler->processor_id != smp_processor_id()) {
 394                 err = -EIO;
 395                 goto failed;
 396         }
 397         /* Set up rx */
 398         memset(&handler->rx, 0, sizeof(handler->rx));
 399         if (handler == special_handler)
 400                 handler->rx.cb.dqrr = special_dqrr;
 401         else
 402                 handler->rx.cb.dqrr = normal_dqrr;
 403         err = qman_create_fq(handler->fqid_rx, 0, &handler->rx);
 404         if (err) {
 405                 pr_crit("qman_create_fq(rx) failed");
 406                 goto failed;
 407         }
 408         memset(&opts, 0, sizeof(opts));
 409         opts.we_mask = cpu_to_be16(QM_INITFQ_WE_FQCTRL |
 410                                    QM_INITFQ_WE_CONTEXTA);
 411         opts.fqd.fq_ctrl = cpu_to_be16(QM_FQCTRL_CTXASTASHING);
 412         qm_fqd_set_stashing(&opts.fqd, 0, STASH_DATA_CL, STASH_CTX_CL);
 413         err = qman_init_fq(&handler->rx, QMAN_INITFQ_FLAG_SCHED |
 414                            QMAN_INITFQ_FLAG_LOCAL, &opts);
 415         if (err) {
 416                 pr_crit("qman_init_fq(rx) failed");
 417                 goto failed;
 418         }
 419         /* Set up tx */
 420         memset(&handler->tx, 0, sizeof(handler->tx));
 421         err = qman_create_fq(handler->fqid_tx, QMAN_FQ_FLAG_NO_MODIFY,
 422                              &handler->tx);
 423         if (err) {
 424                 pr_crit("qman_create_fq(tx) failed");
 425                 goto failed;
 426         }
 427 
 428         return 0;
 429 failed:
 430         return err;
 431 }
 432 
 433 static void init_handler_cb(void *h)
 434 {
 435         if (init_handler(h))
 436                 WARN_ON(1);
 437 }
 438 
 439 static int init_phase2(void)
 440 {
 441         int loop;
 442         u32 fqid = 0;
 443         u32 lfsr = 0xdeadbeef;
 444         struct hp_cpu *hp_cpu;
 445         struct hp_handler *handler;
 446 
 447         for (loop = 0; loop < HP_PER_CPU; loop++) {
 448                 list_for_each_entry(hp_cpu, &hp_cpu_list, node) {
 449                         int err;
 450 
 451                         if (!loop)
 452                                 hp_cpu->iterator = list_first_entry(
 453                                                 &hp_cpu->handlers,
 454                                                 struct hp_handler, node);
 455                         else
 456                                 hp_cpu->iterator = list_entry(
 457                                                 hp_cpu->iterator->node.next,
 458                                                 struct hp_handler, node);
 459                         /* Rx FQID is the previous handler's Tx FQID */
 460                         hp_cpu->iterator->fqid_rx = fqid;
 461                         /* Allocate new FQID for Tx */
 462                         err = qman_alloc_fqid(&fqid);
 463                         if (err) {
 464                                 pr_crit("qman_alloc_fqid() failed");
 465                                 return err;
 466                         }
 467                         hp_cpu->iterator->fqid_tx = fqid;
 468                         /* Rx mixer is the previous handler's Tx mixer */
 469                         hp_cpu->iterator->rx_mixer = lfsr;
 470                         /* Get new mixer for Tx */
 471                         lfsr = do_lfsr(lfsr);
 472                         hp_cpu->iterator->tx_mixer = lfsr;
 473                 }
 474         }
 475         /* Fix up the first handler (fqid_rx==0, rx_mixer=0xdeadbeef) */
 476         hp_cpu = list_first_entry(&hp_cpu_list, struct hp_cpu, node);
 477         handler = list_first_entry(&hp_cpu->handlers, struct hp_handler, node);
 478         if (handler->fqid_rx != 0 || handler->rx_mixer != 0xdeadbeef)
 479                 return 1;
 480         handler->fqid_rx = fqid;
 481         handler->rx_mixer = lfsr;
 482         /* and tag it as our "special" handler */
 483         special_handler = handler;
 484         return 0;
 485 }
 486 
 487 static int init_phase3(void)
 488 {
 489         int loop, err;
 490         struct hp_cpu *hp_cpu;
 491 
 492         for (loop = 0; loop < HP_PER_CPU; loop++) {
 493                 list_for_each_entry(hp_cpu, &hp_cpu_list, node) {
 494                         if (!loop)
 495                                 hp_cpu->iterator = list_first_entry(
 496                                                 &hp_cpu->handlers,
 497                                                 struct hp_handler, node);
 498                         else
 499                                 hp_cpu->iterator = list_entry(
 500                                                 hp_cpu->iterator->node.next,
 501                                                 struct hp_handler, node);
 502                         preempt_disable();
 503                         if (hp_cpu->processor_id == smp_processor_id()) {
 504                                 err = init_handler(hp_cpu->iterator);
 505                                 if (err)
 506                                         return err;
 507                         } else {
 508                                 smp_call_function_single(hp_cpu->processor_id,
 509                                         init_handler_cb, hp_cpu->iterator, 1);
 510                         }
 511                         preempt_enable();
 512                 }
 513         }
 514         return 0;
 515 }
 516 
 517 static int send_first_frame(void *ignore)
 518 {
 519         u32 *p = special_handler->frame_ptr;
 520         u32 lfsr = HP_FIRST_WORD;
 521         int loop, err;
 522         struct qm_fd fd;
 523 
 524         if (special_handler->processor_id != smp_processor_id()) {
 525                 err = -EIO;
 526                 goto failed;
 527         }
 528         memset(&fd, 0, sizeof(fd));
 529         qm_fd_addr_set64(&fd, special_handler->addr);
 530         qm_fd_set_contig_big(&fd, HP_NUM_WORDS * 4);
 531         for (loop = 0; loop < HP_NUM_WORDS; loop++, p++) {
 532                 if (*p != lfsr) {
 533                         err = -EIO;
 534                         pr_crit("corrupt frame data");
 535                         goto failed;
 536                 }
 537                 *p ^= special_handler->tx_mixer;
 538                 lfsr = do_lfsr(lfsr);
 539         }
 540         pr_info("Sending first frame\n");
 541         err = qman_enqueue(&special_handler->tx, &fd);
 542         if (err) {
 543                 pr_crit("qman_enqueue() failed");
 544                 goto failed;
 545         }
 546 
 547         return 0;
 548 failed:
 549         return err;
 550 }
 551 
 552 static void send_first_frame_cb(void *ignore)
 553 {
 554         if (send_first_frame(NULL))
 555                 WARN_ON(1);
 556 }
 557 
 558 int qman_test_stash(void)
 559 {
 560         int err;
 561 
 562         if (cpumask_weight(cpu_online_mask) < 2) {
 563                 pr_info("%s(): skip - only 1 CPU\n", __func__);
 564                 return 0;
 565         }
 566 
 567         pr_info("%s(): Starting\n", __func__);
 568 
 569         hp_cpu_list_length = 0;
 570         loop_counter = 0;
 571         hp_handler_slab = kmem_cache_create("hp_handler_slab",
 572                         sizeof(struct hp_handler), L1_CACHE_BYTES,
 573                         SLAB_HWCACHE_ALIGN, NULL);
 574         if (!hp_handler_slab) {
 575                 err = -EIO;
 576                 pr_crit("kmem_cache_create() failed");
 577                 goto failed;
 578         }
 579 
 580         err = allocate_frame_data();
 581         if (err)
 582                 goto failed;
 583 
 584         /* Init phase 1 */
 585         pr_info("Creating %d handlers per cpu...\n", HP_PER_CPU);
 586         if (on_all_cpus(create_per_cpu_handlers)) {
 587                 err = -EIO;
 588                 pr_crit("on_each_cpu() failed");
 589                 goto failed;
 590         }
 591         pr_info("Number of cpus: %d, total of %d handlers\n",
 592                 hp_cpu_list_length, hp_cpu_list_length * HP_PER_CPU);
 593 
 594         err = init_phase2();
 595         if (err)
 596                 goto failed;
 597 
 598         err = init_phase3();
 599         if (err)
 600                 goto failed;
 601 
 602         preempt_disable();
 603         if (special_handler->processor_id == smp_processor_id()) {
 604                 err = send_first_frame(NULL);
 605                 if (err)
 606                         goto failed;
 607         } else {
 608                 smp_call_function_single(special_handler->processor_id,
 609                                          send_first_frame_cb, NULL, 1);
 610         }
 611         preempt_enable();
 612 
 613         wait_event(queue, loop_counter == HP_LOOPS);
 614         deallocate_frame_data();
 615         if (on_all_cpus(destroy_per_cpu_handlers)) {
 616                 err = -EIO;
 617                 pr_crit("on_each_cpu() failed");
 618                 goto failed;
 619         }
 620         kmem_cache_destroy(hp_handler_slab);
 621         pr_info("%s(): Finished\n", __func__);
 622 
 623         return 0;
 624 failed:
 625         WARN_ON(1);
 626         return err;
 627 }