drivers/ntb/test/ntb_perf.c

   1 /*
   2  * This file is provided under a dual BSD/GPLv2 license.  When using or
   3  *   redistributing this file, you may do so under either license.
   4  *
   5  *   GPL LICENSE SUMMARY
   6  *
   7  *   Copyright(c) 2015 Intel Corporation. All rights reserved.
   8  *
   9  *   This program is free software; you can redistribute it and/or modify
  10  *   it under the terms of version 2 of the GNU General Public License as
  11  *   published by the Free Software Foundation.
  12  *
  13  *   BSD LICENSE
  14  *
  15  *   Copyright(c) 2015 Intel Corporation. All rights reserved.
  16  *
  17  *   Redistribution and use in source and binary forms, with or without
  18  *   modification, are permitted provided that the following conditions
  19  *   are met:
  20  *
  21  *     * Redistributions of source code must retain the above copyright
  22  *       notice, this list of conditions and the following disclaimer.
  23  *     * Redistributions in binary form must reproduce the above copy
  24  *       notice, this list of conditions and the following disclaimer in
  25  *       the documentation and/or other materials provided with the
  26  *       distribution.
  27  *     * Neither the name of Intel Corporation nor the names of its
  28  *       contributors may be used to endorse or promote products derived
  29  *       from this software without specific prior written permission.
  30  *
  31  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  34  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  36  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  37  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  38  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  39  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  40  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  41  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  42  *
  43  *   PCIe NTB Perf Linux driver
  44  */
  45
  46 #include <linux/init.h>
  47 #include <linux/kernel.h>
  48 #include <linux/module.h>
  49 #include <linux/kthread.h>
  50 #include <linux/time.h>
  51 #include <linux/timer.h>
  52 #include <linux/dma-mapping.h>
  53 #include <linux/pci.h>
  54 #include <linux/slab.h>
  55 #include <linux/spinlock.h>
  56 #include <linux/debugfs.h>
  57 #include <linux/dmaengine.h>
  58 #include <linux/delay.h>
  59 #include <linux/sizes.h>
  60 #include <linux/ntb.h>
  61
  62 #define DRIVER_NAME             "ntb_perf"
  63 #define DRIVER_DESCRIPTION      "PCIe NTB Performance Measurement Tool"
  64
  65 #define DRIVER_LICENSE          "Dual BSD/GPL"
  66 #define DRIVER_VERSION          "1.0"
  67 #define DRIVER_AUTHOR           "Dave Jiang <dave.jiang@intel.com>"
  68
  69 #define PERF_LINK_DOWN_TIMEOUT  10
  70 #define PERF_VERSION            0xffff0001
  71 #define MAX_THREADS             32
  72 #define MAX_TEST_SIZE           SZ_1M
  73 #define MAX_SRCS                32
  74 #define DMA_OUT_RESOURCE_TO     50
  75 #define DMA_RETRIES             20
  76 #define SZ_4G                   (1ULL << 32)
  77 #define MAX_SEG_ORDER           20 /* no larger than 1M for kmalloc buffer */
  78
  79 MODULE_LICENSE(DRIVER_LICENSE);
  80 MODULE_VERSION(DRIVER_VERSION);
  81 MODULE_AUTHOR(DRIVER_AUTHOR);
  82 MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
  83
  84 static struct dentry *perf_debugfs_dir;
  85
  86 static unsigned int seg_order = 19; /* 512K */
  87 module_param(seg_order, uint, 0644);
  88 MODULE_PARM_DESC(seg_order, "size order [n^2] of buffer segment for testing");
  89
  90 static unsigned int run_order = 32; /* 4G */
  91 module_param(run_order, uint, 0644);
  92 MODULE_PARM_DESC(run_order, "size order [n^2] of total data to transfer");
  93
  94 static bool use_dma; /* default to 0 */
  95 module_param(use_dma, bool, 0644);
  96 MODULE_PARM_DESC(use_dma, "Using DMA engine to measure performance");
  97
  98 struct perf_mw {
  99         phys_addr_t     phys_addr;
 100         resource_size_t phys_size;
 101         resource_size_t xlat_align;
 102         resource_size_t xlat_align_size;
 103         void __iomem    *vbase;
 104         size_t          xlat_size;
 105         size_t          buf_size;
 106         void            *virt_addr;
 107         dma_addr_t      dma_addr;
 108 };
 109
 110 struct perf_ctx;
 111
 112 struct pthr_ctx {
 113         struct task_struct      *thread;
 114         struct perf_ctx         *perf;
 115         atomic_t                dma_sync;
 116         struct dma_chan         *dma_chan;
 117         int                     dma_prep_err;
 118         int                     src_idx;
 119         void                    *srcs[MAX_SRCS];
 120 };
 121
 122 struct perf_ctx {
 123         struct ntb_dev          *ntb;
 124         spinlock_t              db_lock;
 125         struct perf_mw          mw;
 126         bool                    link_is_up;
 127         struct work_struct      link_cleanup;
 128         struct delayed_work     link_work;
 129         struct dentry           *debugfs_node_dir;
 130         struct dentry           *debugfs_run;
 131         struct dentry           *debugfs_threads;
 132         u8                      perf_threads;
 133         bool                    run;
 134         struct pthr_ctx         pthr_ctx[MAX_THREADS];
 135         atomic_t                tsync;
 136 };
 137
 138 enum {
 139         VERSION = 0,
 140         MW_SZ_HIGH,
 141         MW_SZ_LOW,
 142         SPAD_MSG,
 143         SPAD_ACK,
 144         MAX_SPAD
 145 };
 146
 147 static void perf_link_event(void *ctx)
 148 {
 149         struct perf_ctx *perf = ctx;
 150
 151         if (ntb_link_is_up(perf->ntb, NULL, NULL) == 1)
 152                 schedule_delayed_work(&perf->link_work, 2*HZ);
 153         else
 154                 schedule_work(&perf->link_cleanup);
 155 }
 156
 157 static void perf_db_event(void *ctx, int vec)
 158 {
 159         struct perf_ctx *perf = ctx;
 160         u64 db_bits, db_mask;
 161
 162         db_mask = ntb_db_vector_mask(perf->ntb, vec);
 163         db_bits = ntb_db_read(perf->ntb);
 164
 165         dev_dbg(&perf->ntb->dev, "doorbell vec %d mask %#llx bits %#llx\n",
 166                 vec, db_mask, db_bits);
 167 }
 168
 169 static const struct ntb_ctx_ops perf_ops = {
 170         .link_event = perf_link_event,
 171         .db_event = perf_db_event,
 172 };
 173
 174 static void perf_copy_callback(void *data)
 175 {
 176         struct pthr_ctx *pctx = data;
 177
 178         atomic_dec(&pctx->dma_sync);
 179 }
 180
 181 static ssize_t perf_copy(struct pthr_ctx *pctx, char __iomem *dst,
 182                          char *src, size_t size)
 183 {
 184         struct perf_ctx *perf = pctx->perf;
 185         struct dma_async_tx_descriptor *txd;
 186         struct dma_chan *chan = pctx->dma_chan;
 187         struct dma_device *device;
 188         struct dmaengine_unmap_data *unmap;
 189         dma_cookie_t cookie;
 190         size_t src_off, dst_off;
 191         struct perf_mw *mw = &perf->mw;
 192         void __iomem *vbase;
 193         void __iomem *dst_vaddr;
 194         dma_addr_t dst_phys;
 195         int retries = 0;
 196
 197         if (!use_dma) {
 198                 memcpy_toio(dst, src, size);
 199                 return size;
 200         }
 201
 202         if (!chan) {
 203                 dev_err(&perf->ntb->dev, "DMA engine does not exist\n");
 204                 return -EINVAL;
 205         }
 206
 207         device = chan->device;
 208         src_off = (uintptr_t)src & ~PAGE_MASK;
 209         dst_off = (uintptr_t __force)dst & ~PAGE_MASK;
 210
 211         if (!is_dma_copy_aligned(device, src_off, dst_off, size))
 212                 return -ENODEV;
 213
 214         vbase = mw->vbase;
 215         dst_vaddr = dst;
 216         dst_phys = mw->phys_addr + (dst_vaddr - vbase);
 217
 218         unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT);
 219         if (!unmap)
 220                 return -ENOMEM;
 221
 222         unmap->len = size;
 223         unmap->addr[0] = dma_map_page(device->dev, virt_to_page(src),
 224                                       src_off, size, DMA_TO_DEVICE);
 225         if (dma_mapping_error(device->dev, unmap->addr[0]))
 226                 goto err_get_unmap;
 227
 228         unmap->to_cnt = 1;
 229
 230         do {
 231                 txd = device->device_prep_dma_memcpy(chan, dst_phys,
 232                                                      unmap->addr[0],
 233                                                      size, DMA_PREP_INTERRUPT);
 234                 if (!txd) {
 235                         set_current_state(TASK_INTERRUPTIBLE);
 236                         schedule_timeout(DMA_OUT_RESOURCE_TO);
 237                 }
 238         } while (!txd && (++retries < DMA_RETRIES));
 239
 240         if (!txd) {
 241                 pctx->dma_prep_err++;
 242                 goto err_get_unmap;
 243         }
 244
 245         txd->callback = perf_copy_callback;
 246         txd->callback_param = pctx;
 247         dma_set_unmap(txd, unmap);
 248
 249         cookie = dmaengine_submit(txd);
 250         if (dma_submit_error(cookie))
 251                 goto err_set_unmap;
 252
 253         atomic_inc(&pctx->dma_sync);
 254         dma_async_issue_pending(chan);
 255
 256         return size;
 257
 258 err_set_unmap:
 259         dmaengine_unmap_put(unmap);
 260 err_get_unmap:
 261         dmaengine_unmap_put(unmap);
 262         return 0;
 263 }
 264
 265 static int perf_move_data(struct pthr_ctx *pctx, char __iomem *dst, char *src,
 266                           u64 buf_size, u64 win_size, u64 total)
 267 {
 268         int chunks, total_chunks, i;
 269         int copied_chunks = 0;
 270         u64 copied = 0, result;
 271         char __iomem *tmp = dst;
 272         u64 perf, diff_us;
 273         ktime_t kstart, kstop, kdiff;
 274
 275         chunks = div64_u64(win_size, buf_size);
 276         total_chunks = div64_u64(total, buf_size);
 277         kstart = ktime_get();
 278
 279         for (i = 0; i < total_chunks; i++) {
 280                 result = perf_copy(pctx, tmp, src, buf_size);
 281                 copied += result;
 282                 copied_chunks++;
 283                 if (copied_chunks == chunks) {
 284                         tmp = dst;
 285                         copied_chunks = 0;
 286                 } else
 287                         tmp += buf_size;
 288
 289                 /* Probably should schedule every 4GB to prevent soft hang. */
 290                 if (((copied % SZ_4G) == 0) && !use_dma) {
 291                         set_current_state(TASK_INTERRUPTIBLE);
 292                         schedule_timeout(1);
 293                 }
 294         }
 295
 296         if (use_dma) {
 297                 pr_info("%s: All DMA descriptors submitted\n", current->comm);
 298                 while (atomic_read(&pctx->dma_sync) != 0)
 299                         msleep(20);
 300         }
 301
 302         kstop = ktime_get();
 303         kdiff = ktime_sub(kstop, kstart);
 304         diff_us = ktime_to_us(kdiff);
 305
 306         pr_info("%s: copied %llu bytes\n", current->comm, copied);
 307
 308         pr_info("%s: lasted %llu usecs\n", current->comm, diff_us);
 309
 310         perf = div64_u64(copied, diff_us);
 311
 312         pr_info("%s: MBytes/s: %llu\n", current->comm, perf);
 313
 314         return 0;
 315 }
 316
 317 static bool perf_dma_filter_fn(struct dma_chan *chan, void *node)
 318 {
 319         return dev_to_node(&chan->dev->device) == (int)(unsigned long)node;
 320 }
 321
 322 static int ntb_perf_thread(void *data)
 323 {
 324         struct pthr_ctx *pctx = data;
 325         struct perf_ctx *perf = pctx->perf;
 326         struct pci_dev *pdev = perf->ntb->pdev;
 327         struct perf_mw *mw = &perf->mw;
 328         char __iomem *dst;
 329         u64 win_size, buf_size, total;
 330         void *src;
 331         int rc, node, i;
 332         struct dma_chan *dma_chan = NULL;
 333
 334         pr_info("kthread %s starting...\n", current->comm);
 335
 336         node = dev_to_node(&pdev->dev);
 337
 338         if (use_dma && !pctx->dma_chan) {
 339                 dma_cap_mask_t dma_mask;
 340
 341                 dma_cap_zero(dma_mask);
 342                 dma_cap_set(DMA_MEMCPY, dma_mask);
 343                 dma_chan = dma_request_channel(dma_mask, perf_dma_filter_fn,
 344                                                (void *)(unsigned long)node);
 345                 if (!dma_chan) {
 346                         pr_warn("%s: cannot acquire DMA channel, quitting\n",
 347                                 current->comm);
 348                         return -ENODEV;
 349                 }
 350                 pctx->dma_chan = dma_chan;
 351         }
 352
 353         for (i = 0; i < MAX_SRCS; i++) {
 354                 pctx->srcs[i] = kmalloc_node(MAX_TEST_SIZE, GFP_KERNEL, node);
 355                 if (!pctx->srcs[i]) {
 356                         rc = -ENOMEM;
 357                         goto err;
 358                 }
 359         }
 360
 361         win_size = mw->phys_size;
 362         buf_size = 1ULL << seg_order;
 363         total = 1ULL << run_order;
 364
 365         if (buf_size > MAX_TEST_SIZE)
 366                 buf_size = MAX_TEST_SIZE;
 367
 368         dst = (char __iomem *)mw->vbase;
 369
 370         atomic_inc(&perf->tsync);
 371         while (atomic_read(&perf->tsync) != perf->perf_threads)
 372                 schedule();
 373
 374         src = pctx->srcs[pctx->src_idx];
 375         pctx->src_idx = (pctx->src_idx + 1) & (MAX_SRCS - 1);
 376
 377         rc = perf_move_data(pctx, dst, src, buf_size, win_size, total);
 378
 379         atomic_dec(&perf->tsync);
 380
 381         if (rc < 0) {
 382                 pr_err("%s: failed\n", current->comm);
 383                 rc = -ENXIO;
 384                 goto err;
 385         }
 386
 387         for (i = 0; i < MAX_SRCS; i++) {
 388                 kfree(pctx->srcs[i]);
 389                 pctx->srcs[i] = NULL;
 390         }
 391
 392         return 0;
 393
 394 err:
 395         for (i = 0; i < MAX_SRCS; i++) {
 396                 kfree(pctx->srcs[i]);
 397                 pctx->srcs[i] = NULL;
 398         }
 399
 400         if (dma_chan) {
 401                 dma_release_channel(dma_chan);
 402                 pctx->dma_chan = NULL;
 403         }
 404
 405         return rc;
 406 }
 407
 408 static void perf_free_mw(struct perf_ctx *perf)
 409 {
 410         struct perf_mw *mw = &perf->mw;
 411         struct pci_dev *pdev = perf->ntb->pdev;
 412
 413         if (!mw->virt_addr)
 414                 return;
 415
 416         ntb_mw_clear_trans(perf->ntb, 0);
 417         dma_free_coherent(&pdev->dev, mw->buf_size,
 418                           mw->virt_addr, mw->dma_addr);
 419         mw->xlat_size = 0;
 420         mw->buf_size = 0;
 421         mw->virt_addr = NULL;
 422 }
 423
 424 static int perf_set_mw(struct perf_ctx *perf, resource_size_t size)
 425 {
 426         struct perf_mw *mw = &perf->mw;
 427         size_t xlat_size, buf_size;
 428         int rc;
 429
 430         if (!size)
 431                 return -EINVAL;
 432
 433         xlat_size = round_up(size, mw->xlat_align_size);
 434         buf_size = round_up(size, mw->xlat_align);
 435
 436         if (mw->xlat_size == xlat_size)
 437                 return 0;
 438
 439         if (mw->buf_size)
 440                 perf_free_mw(perf);
 441
 442         mw->xlat_size = xlat_size;
 443         mw->buf_size = buf_size;
 444
 445         mw->virt_addr = dma_alloc_coherent(&perf->ntb->pdev->dev, buf_size,
 446                                            &mw->dma_addr, GFP_KERNEL);
 447         if (!mw->virt_addr) {
 448                 mw->xlat_size = 0;
 449                 mw->buf_size = 0;
 450         }
 451
 452         rc = ntb_mw_set_trans(perf->ntb, 0, mw->dma_addr, mw->xlat_size);
 453         if (rc) {
 454                 dev_err(&perf->ntb->dev, "Unable to set mw0 translation\n");
 455                 perf_free_mw(perf);
 456                 return -EIO;
 457         }
 458
 459         return 0;
 460 }
 461
 462 static void perf_link_work(struct work_struct *work)
 463 {
 464         struct perf_ctx *perf =
 465                 container_of(work, struct perf_ctx, link_work.work);
 466         struct ntb_dev *ndev = perf->ntb;
 467         struct pci_dev *pdev = ndev->pdev;
 468         u32 val;
 469         u64 size;
 470         int rc;
 471
 472         dev_dbg(&perf->ntb->pdev->dev, "%s called\n", __func__);
 473
 474         size = perf->mw.phys_size;
 475         ntb_peer_spad_write(ndev, MW_SZ_HIGH, upper_32_bits(size));
 476         ntb_peer_spad_write(ndev, MW_SZ_LOW, lower_32_bits(size));
 477         ntb_peer_spad_write(ndev, VERSION, PERF_VERSION);
 478
 479         /* now read what peer wrote */
 480         val = ntb_spad_read(ndev, VERSION);
 481         if (val != PERF_VERSION) {
 482                 dev_dbg(&pdev->dev, "Remote version = %#x\n", val);
 483                 goto out;
 484         }
 485
 486         val = ntb_spad_read(ndev, MW_SZ_HIGH);
 487         size = (u64)val << 32;
 488
 489         val = ntb_spad_read(ndev, MW_SZ_LOW);
 490         size |= val;
 491
 492         dev_dbg(&pdev->dev, "Remote MW size = %#llx\n", size);
 493
 494         rc = perf_set_mw(perf, size);
 495         if (rc)
 496                 goto out1;
 497
 498         perf->link_is_up = true;
 499
 500         return;
 501
 502 out1:
 503         perf_free_mw(perf);
 504
 505 out:
 506         if (ntb_link_is_up(ndev, NULL, NULL) == 1)
 507                 schedule_delayed_work(&perf->link_work,
 508                                       msecs_to_jiffies(PERF_LINK_DOWN_TIMEOUT));
 509 }
 510
 511 static void perf_link_cleanup(struct work_struct *work)
 512 {
 513         struct perf_ctx *perf = container_of(work,
 514                                              struct perf_ctx,
 515                                              link_cleanup);
 516
 517         dev_dbg(&perf->ntb->pdev->dev, "%s called\n", __func__);
 518
 519         if (!perf->link_is_up)
 520                 cancel_delayed_work_sync(&perf->link_work);
 521 }
 522
 523 static int perf_setup_mw(struct ntb_dev *ntb, struct perf_ctx *perf)
 524 {
 525         struct perf_mw *mw;
 526         int rc;
 527
 528         mw = &perf->mw;
 529
 530         rc = ntb_mw_get_range(ntb, 0, &mw->phys_addr, &mw->phys_size,
 531                               &mw->xlat_align, &mw->xlat_align_size);
 532         if (rc)
 533                 return rc;
 534
 535         perf->mw.vbase = ioremap_wc(mw->phys_addr, mw->phys_size);
 536         if (!mw->vbase)
 537                 return -ENOMEM;
 538
 539         return 0;
 540 }
 541
 542 static ssize_t debugfs_run_read(struct file *filp, char __user *ubuf,
 543                                 size_t count, loff_t *offp)
 544 {
 545         struct perf_ctx *perf = filp->private_data;
 546         char *buf;
 547         ssize_t ret, out_offset;
 548
 549         if (!perf)
 550                 return 0;
 551
 552         buf = kmalloc(64, GFP_KERNEL);
 553         if (!buf)
 554                 return -ENOMEM;
 555         out_offset = snprintf(buf, 64, "%d\n", perf->run);
 556         ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
 557         kfree(buf);
 558
 559         return ret;
 560 }
 561
 562 static void threads_cleanup(struct perf_ctx *perf)
 563 {
 564         struct pthr_ctx *pctx;
 565         int i;
 566
 567         perf->run = false;
 568         for (i = 0; i < MAX_THREADS; i++) {
 569                 pctx = &perf->pthr_ctx[i];
 570                 if (pctx->thread) {
 571                         kthread_stop(pctx->thread);
 572                         pctx->thread = NULL;
 573                 }
 574         }
 575 }
 576
 577 static ssize_t debugfs_run_write(struct file *filp, const char __user *ubuf,
 578                                  size_t count, loff_t *offp)
 579 {
 580         struct perf_ctx *perf = filp->private_data;
 581         int node, i;
 582
 583         if (!perf->link_is_up)
 584                 return 0;
 585
 586         if (perf->perf_threads == 0)
 587                 return 0;
 588
 589         if (atomic_read(&perf->tsync) == 0)
 590                 perf->run = false;
 591
 592         if (perf->run)
 593                 threads_cleanup(perf);
 594         else {
 595                 perf->run = true;
 596
 597                 if (perf->perf_threads > MAX_THREADS) {
 598                         perf->perf_threads = MAX_THREADS;
 599                         pr_info("Reset total threads to: %u\n", MAX_THREADS);
 600                 }
 601
 602                 /* no greater than 1M */
 603                 if (seg_order > MAX_SEG_ORDER) {
 604                         seg_order = MAX_SEG_ORDER;
 605                         pr_info("Fix seg_order to %u\n", seg_order);
 606                 }
 607
 608                 if (run_order < seg_order) {
 609                         run_order = seg_order;
 610                         pr_info("Fix run_order to %u\n", run_order);
 611                 }
 612
 613                 node = dev_to_node(&perf->ntb->pdev->dev);
 614                 /* launch kernel thread */
 615                 for (i = 0; i < perf->perf_threads; i++) {
 616                         struct pthr_ctx *pctx;
 617
 618                         pctx = &perf->pthr_ctx[i];
 619                         atomic_set(&pctx->dma_sync, 0);
 620                         pctx->perf = perf;
 621                         pctx->thread =
 622                                 kthread_create_on_node(ntb_perf_thread,
 623                                                        (void *)pctx,
 624                                                        node, "ntb_perf %d", i);
 625                         if (IS_ERR(pctx->thread)) {
 626                                 pctx->thread = NULL;
 627                                 goto err;
 628                         } else
 629                                 wake_up_process(pctx->thread);
 630
 631                         if (perf->run == false)
 632                                 return -ENXIO;
 633                 }
 634
 635         }
 636
 637         return count;
 638
 639 err:
 640         threads_cleanup(perf);
 641         return -ENXIO;
 642 }
 643
 644 static const struct file_operations ntb_perf_debugfs_run = {
 645         .owner = THIS_MODULE,
 646         .open = simple_open,
 647         .read = debugfs_run_read,
 648         .write = debugfs_run_write,
 649 };
 650
 651 static int perf_debugfs_setup(struct perf_ctx *perf)
 652 {
 653         struct pci_dev *pdev = perf->ntb->pdev;
 654
 655         if (!debugfs_initialized())
 656                 return -ENODEV;
 657
 658         if (!perf_debugfs_dir) {
 659                 perf_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
 660                 if (!perf_debugfs_dir)
 661                         return -ENODEV;
 662         }
 663
 664         perf->debugfs_node_dir = debugfs_create_dir(pci_name(pdev),
 665                                                     perf_debugfs_dir);
 666         if (!perf->debugfs_node_dir)
 667                 return -ENODEV;
 668
 669         perf->debugfs_run = debugfs_create_file("run", S_IRUSR | S_IWUSR,
 670                                                 perf->debugfs_node_dir, perf,
 671                                                 &ntb_perf_debugfs_run);
 672         if (!perf->debugfs_run)
 673                 return -ENODEV;
 674
 675         perf->debugfs_threads = debugfs_create_u8("threads", S_IRUSR | S_IWUSR,
 676                                                   perf->debugfs_node_dir,
 677                                                   &perf->perf_threads);
 678         if (!perf->debugfs_threads)
 679                 return -ENODEV;
 680
 681         return 0;
 682 }
 683
 684 static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb)
 685 {
 686         struct pci_dev *pdev = ntb->pdev;
 687         struct perf_ctx *perf;
 688         int node;
 689         int rc = 0;
 690
 691         node = dev_to_node(&pdev->dev);
 692
 693         perf = kzalloc_node(sizeof(*perf), GFP_KERNEL, node);
 694         if (!perf) {
 695                 rc = -ENOMEM;
 696                 goto err_perf;
 697         }
 698
 699         perf->ntb = ntb;
 700         perf->perf_threads = 1;
 701         atomic_set(&perf->tsync, 0);
 702         perf->run = false;
 703         spin_lock_init(&perf->db_lock);
 704         perf_setup_mw(ntb, perf);
 705         INIT_DELAYED_WORK(&perf->link_work, perf_link_work);
 706         INIT_WORK(&perf->link_cleanup, perf_link_cleanup);
 707
 708         rc = ntb_set_ctx(ntb, perf, &perf_ops);
 709         if (rc)
 710                 goto err_ctx;
 711
 712         perf->link_is_up = false;
 713         ntb_link_enable(ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
 714         ntb_link_event(ntb);
 715
 716         rc = perf_debugfs_setup(perf);
 717         if (rc)
 718                 goto err_ctx;
 719
 720         return 0;
 721
 722 err_ctx:
 723         cancel_delayed_work_sync(&perf->link_work);
 724         cancel_work_sync(&perf->link_cleanup);
 725         kfree(perf);
 726 err_perf:
 727         return rc;
 728 }
 729
 730 static void perf_remove(struct ntb_client *client, struct ntb_dev *ntb)
 731 {
 732         struct perf_ctx *perf = ntb->ctx;
 733         int i;
 734
 735         dev_dbg(&perf->ntb->dev, "%s called\n", __func__);
 736
 737         cancel_delayed_work_sync(&perf->link_work);
 738         cancel_work_sync(&perf->link_cleanup);
 739
 740         ntb_clear_ctx(ntb);
 741         ntb_link_disable(ntb);
 742
 743         debugfs_remove_recursive(perf_debugfs_dir);
 744         perf_debugfs_dir = NULL;
 745
 746         if (use_dma) {
 747                 for (i = 0; i < MAX_THREADS; i++) {
 748                         struct pthr_ctx *pctx = &perf->pthr_ctx[i];
 749
 750                         if (pctx->dma_chan)
 751                                 dma_release_channel(pctx->dma_chan);
 752                 }
 753         }
 754
 755         kfree(perf);
 756 }
 757
 758 static struct ntb_client perf_client = {
 759         .ops = {
 760                 .probe = perf_probe,
 761                 .remove = perf_remove,
 762         },
 763 };
 764 module_ntb_client(perf_client);