summaryrefslogtreecommitdiffstats
path: root/drivers/ntb/test/ntb_perf.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/ntb/test/ntb_perf.c')
-rw-r--r--drivers/ntb/test/ntb_perf.c748
1 files changed, 748 insertions, 0 deletions
diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c
new file mode 100644
index 000000000000..c8a37ba4b4f9
--- /dev/null
+++ b/drivers/ntb/test/ntb_perf.c
@@ -0,0 +1,748 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2015 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2015 Intel Corporation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copy
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * PCIe NTB Perf Linux driver
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/time.h>
+#include <linux/timer.h>
+#include <linux/dma-mapping.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/debugfs.h>
+#include <linux/dmaengine.h>
+#include <linux/delay.h>
+#include <linux/sizes.h>
+#include <linux/ntb.h>
+
+#define DRIVER_NAME "ntb_perf"
+#define DRIVER_DESCRIPTION "PCIe NTB Performance Measurement Tool"
+
+#define DRIVER_LICENSE "Dual BSD/GPL"
+#define DRIVER_VERSION "1.0"
+#define DRIVER_AUTHOR "Dave Jiang <dave.jiang@intel.com>"
+
+#define PERF_LINK_DOWN_TIMEOUT 10
+#define PERF_VERSION 0xffff0001
+#define MAX_THREADS 32
+#define MAX_TEST_SIZE SZ_1M
+#define MAX_SRCS 32
+#define DMA_OUT_RESOURCE_TO 50
+#define DMA_RETRIES 20
+#define SZ_4G (1ULL << 32)
+#define MAX_SEG_ORDER 20 /* no larger than 1M for kmalloc buffer */
+
+MODULE_LICENSE(DRIVER_LICENSE);
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
+
+static struct dentry *perf_debugfs_dir;
+
+static unsigned int seg_order = 19; /* 512K */
+module_param(seg_order, uint, 0644);
+MODULE_PARM_DESC(seg_order, "size order [n^2] of buffer segment for testing");
+
+static unsigned int run_order = 32; /* 4G */
+module_param(run_order, uint, 0644);
+MODULE_PARM_DESC(run_order, "size order [n^2] of total data to transfer");
+
+static bool use_dma; /* default to 0 */
+module_param(use_dma, bool, 0644);
+MODULE_PARM_DESC(use_dma, "Using DMA engine to measure performance");
+
+struct perf_mw {
+ phys_addr_t phys_addr;
+ resource_size_t phys_size;
+ resource_size_t xlat_align;
+ resource_size_t xlat_align_size;
+ void __iomem *vbase;
+ size_t xlat_size;
+ size_t buf_size;
+ void *virt_addr;
+ dma_addr_t dma_addr;
+};
+
+struct perf_ctx;
+
+struct pthr_ctx {
+ struct task_struct *thread;
+ struct perf_ctx *perf;
+ atomic_t dma_sync;
+ struct dma_chan *dma_chan;
+ int dma_prep_err;
+ int src_idx;
+ void *srcs[MAX_SRCS];
+};
+
+struct perf_ctx {
+ struct ntb_dev *ntb;
+ spinlock_t db_lock;
+ struct perf_mw mw;
+ bool link_is_up;
+ struct work_struct link_cleanup;
+ struct delayed_work link_work;
+ struct dentry *debugfs_node_dir;
+ struct dentry *debugfs_run;
+ struct dentry *debugfs_threads;
+ u8 perf_threads;
+ bool run;
+ struct pthr_ctx pthr_ctx[MAX_THREADS];
+ atomic_t tsync;
+};
+
+enum {
+ VERSION = 0,
+ MW_SZ_HIGH,
+ MW_SZ_LOW,
+ SPAD_MSG,
+ SPAD_ACK,
+ MAX_SPAD
+};
+
+static void perf_link_event(void *ctx)
+{
+ struct perf_ctx *perf = ctx;
+
+ if (ntb_link_is_up(perf->ntb, NULL, NULL) == 1)
+ schedule_delayed_work(&perf->link_work, 2*HZ);
+ else
+ schedule_work(&perf->link_cleanup);
+}
+
+static void perf_db_event(void *ctx, int vec)
+{
+ struct perf_ctx *perf = ctx;
+ u64 db_bits, db_mask;
+
+ db_mask = ntb_db_vector_mask(perf->ntb, vec);
+ db_bits = ntb_db_read(perf->ntb);
+
+ dev_dbg(&perf->ntb->dev, "doorbell vec %d mask %#llx bits %#llx\n",
+ vec, db_mask, db_bits);
+}
+
+static const struct ntb_ctx_ops perf_ops = {
+ .link_event = perf_link_event,
+ .db_event = perf_db_event,
+};
+
+static void perf_copy_callback(void *data)
+{
+ struct pthr_ctx *pctx = data;
+
+ atomic_dec(&pctx->dma_sync);
+}
+
+static ssize_t perf_copy(struct pthr_ctx *pctx, char *dst,
+ char *src, size_t size)
+{
+ struct perf_ctx *perf = pctx->perf;
+ struct dma_async_tx_descriptor *txd;
+ struct dma_chan *chan = pctx->dma_chan;
+ struct dma_device *device;
+ struct dmaengine_unmap_data *unmap;
+ dma_cookie_t cookie;
+ size_t src_off, dst_off;
+ struct perf_mw *mw = &perf->mw;
+ u64 vbase, dst_vaddr;
+ dma_addr_t dst_phys;
+ int retries = 0;
+
+ if (!use_dma) {
+ memcpy_toio(dst, src, size);
+ return size;
+ }
+
+ if (!chan) {
+ dev_err(&perf->ntb->dev, "DMA engine does not exist\n");
+ return -EINVAL;
+ }
+
+ device = chan->device;
+ src_off = (size_t)src & ~PAGE_MASK;
+ dst_off = (size_t)dst & ~PAGE_MASK;
+
+ if (!is_dma_copy_aligned(device, src_off, dst_off, size))
+ return -ENODEV;
+
+ vbase = (u64)(u64 *)mw->vbase;
+ dst_vaddr = (u64)(u64 *)dst;
+ dst_phys = mw->phys_addr + (dst_vaddr - vbase);
+
+ unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT);
+ if (!unmap)
+ return -ENOMEM;
+
+ unmap->len = size;
+ unmap->addr[0] = dma_map_page(device->dev, virt_to_page(src),
+ src_off, size, DMA_TO_DEVICE);
+ if (dma_mapping_error(device->dev, unmap->addr[0]))
+ goto err_get_unmap;
+
+ unmap->to_cnt = 1;
+
+ do {
+ txd = device->device_prep_dma_memcpy(chan, dst_phys,
+ unmap->addr[0],
+ size, DMA_PREP_INTERRUPT);
+ if (!txd) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(DMA_OUT_RESOURCE_TO);
+ }
+ } while (!txd && (++retries < DMA_RETRIES));
+
+ if (!txd) {
+ pctx->dma_prep_err++;
+ goto err_get_unmap;
+ }
+
+ txd->callback = perf_copy_callback;
+ txd->callback_param = pctx;
+ dma_set_unmap(txd, unmap);
+
+ cookie = dmaengine_submit(txd);
+ if (dma_submit_error(cookie))
+ goto err_set_unmap;
+
+ atomic_inc(&pctx->dma_sync);
+ dma_async_issue_pending(chan);
+
+ return size;
+
+err_set_unmap:
+ dmaengine_unmap_put(unmap);
+err_get_unmap:
+ dmaengine_unmap_put(unmap);
+ return 0;
+}
+
+static int perf_move_data(struct pthr_ctx *pctx, char *dst, char *src,
+ u64 buf_size, u64 win_size, u64 total)
+{
+ int chunks, total_chunks, i;
+ int copied_chunks = 0;
+ u64 copied = 0, result;
+ char *tmp = dst;
+ u64 perf, diff_us;
+ ktime_t kstart, kstop, kdiff;
+
+ chunks = div64_u64(win_size, buf_size);
+ total_chunks = div64_u64(total, buf_size);
+ kstart = ktime_get();
+
+ for (i = 0; i < total_chunks; i++) {
+ result = perf_copy(pctx, tmp, src, buf_size);
+ copied += result;
+ copied_chunks++;
+ if (copied_chunks == chunks) {
+ tmp = dst;
+ copied_chunks = 0;
+ } else
+ tmp += buf_size;
+
+ /* Probably should schedule every 4GB to prevent soft hang. */
+ if (((copied % SZ_4G) == 0) && !use_dma) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(1);
+ }
+ }
+
+ if (use_dma) {
+ pr_info("%s: All DMA descriptors submitted\n", current->comm);
+ while (atomic_read(&pctx->dma_sync) != 0)
+ msleep(20);
+ }
+
+ kstop = ktime_get();
+ kdiff = ktime_sub(kstop, kstart);
+ diff_us = ktime_to_us(kdiff);
+
+ pr_info("%s: copied %llu bytes\n", current->comm, copied);
+
+ pr_info("%s: lasted %llu usecs\n", current->comm, diff_us);
+
+ perf = div64_u64(copied, diff_us);
+
+ pr_info("%s: MBytes/s: %llu\n", current->comm, perf);
+
+ return 0;
+}
+
+static bool perf_dma_filter_fn(struct dma_chan *chan, void *node)
+{
+ return dev_to_node(&chan->dev->device) == (int)(unsigned long)node;
+}
+
+static int ntb_perf_thread(void *data)
+{
+ struct pthr_ctx *pctx = data;
+ struct perf_ctx *perf = pctx->perf;
+ struct pci_dev *pdev = perf->ntb->pdev;
+ struct perf_mw *mw = &perf->mw;
+ char *dst;
+ u64 win_size, buf_size, total;
+ void *src;
+ int rc, node, i;
+ struct dma_chan *dma_chan = NULL;
+
+ pr_info("kthread %s starting...\n", current->comm);
+
+ node = dev_to_node(&pdev->dev);
+
+ if (use_dma && !pctx->dma_chan) {
+ dma_cap_mask_t dma_mask;
+
+ dma_cap_zero(dma_mask);
+ dma_cap_set(DMA_MEMCPY, dma_mask);
+ dma_chan = dma_request_channel(dma_mask, perf_dma_filter_fn,
+ (void *)(unsigned long)node);
+ if (!dma_chan) {
+ pr_warn("%s: cannot acquire DMA channel, quitting\n",
+ current->comm);
+ return -ENODEV;
+ }
+ pctx->dma_chan = dma_chan;
+ }
+
+ for (i = 0; i < MAX_SRCS; i++) {
+ pctx->srcs[i] = kmalloc_node(MAX_TEST_SIZE, GFP_KERNEL, node);
+ if (!pctx->srcs[i]) {
+ rc = -ENOMEM;
+ goto err;
+ }
+ }
+
+ win_size = mw->phys_size;
+ buf_size = 1ULL << seg_order;
+ total = 1ULL << run_order;
+
+ if (buf_size > MAX_TEST_SIZE)
+ buf_size = MAX_TEST_SIZE;
+
+ dst = (char *)mw->vbase;
+
+ atomic_inc(&perf->tsync);
+ while (atomic_read(&perf->tsync) != perf->perf_threads)
+ schedule();
+
+ src = pctx->srcs[pctx->src_idx];
+ pctx->src_idx = (pctx->src_idx + 1) & (MAX_SRCS - 1);
+
+ rc = perf_move_data(pctx, dst, src, buf_size, win_size, total);
+
+ atomic_dec(&perf->tsync);
+
+ if (rc < 0) {
+ pr_err("%s: failed\n", current->comm);
+ rc = -ENXIO;
+ goto err;
+ }
+
+ for (i = 0; i < MAX_SRCS; i++) {
+ kfree(pctx->srcs[i]);
+ pctx->srcs[i] = NULL;
+ }
+
+ return 0;
+
+err:
+ for (i = 0; i < MAX_SRCS; i++) {
+ kfree(pctx->srcs[i]);
+ pctx->srcs[i] = NULL;
+ }
+
+ if (dma_chan) {
+ dma_release_channel(dma_chan);
+ pctx->dma_chan = NULL;
+ }
+
+ return rc;
+}
+
+static void perf_free_mw(struct perf_ctx *perf)
+{
+ struct perf_mw *mw = &perf->mw;
+ struct pci_dev *pdev = perf->ntb->pdev;
+
+ if (!mw->virt_addr)
+ return;
+
+ ntb_mw_clear_trans(perf->ntb, 0);
+ dma_free_coherent(&pdev->dev, mw->buf_size,
+ mw->virt_addr, mw->dma_addr);
+ mw->xlat_size = 0;
+ mw->buf_size = 0;
+ mw->virt_addr = NULL;
+}
+
+static int perf_set_mw(struct perf_ctx *perf, resource_size_t size)
+{
+ struct perf_mw *mw = &perf->mw;
+ size_t xlat_size, buf_size;
+
+ if (!size)
+ return -EINVAL;
+
+ xlat_size = round_up(size, mw->xlat_align_size);
+ buf_size = round_up(size, mw->xlat_align);
+
+ if (mw->xlat_size == xlat_size)
+ return 0;
+
+ if (mw->buf_size)
+ perf_free_mw(perf);
+
+ mw->xlat_size = xlat_size;
+ mw->buf_size = buf_size;
+
+ mw->virt_addr = dma_alloc_coherent(&perf->ntb->pdev->dev, buf_size,
+ &mw->dma_addr, GFP_KERNEL);
+ if (!mw->virt_addr) {
+ mw->xlat_size = 0;
+ mw->buf_size = 0;
+ }
+
+ return 0;
+}
+
+static void perf_link_work(struct work_struct *work)
+{
+ struct perf_ctx *perf =
+ container_of(work, struct perf_ctx, link_work.work);
+ struct ntb_dev *ndev = perf->ntb;
+ struct pci_dev *pdev = ndev->pdev;
+ u32 val;
+ u64 size;
+ int rc;
+
+ dev_dbg(&perf->ntb->pdev->dev, "%s called\n", __func__);
+
+ size = perf->mw.phys_size;
+ ntb_peer_spad_write(ndev, MW_SZ_HIGH, upper_32_bits(size));
+ ntb_peer_spad_write(ndev, MW_SZ_LOW, lower_32_bits(size));
+ ntb_peer_spad_write(ndev, VERSION, PERF_VERSION);
+
+ /* now read what peer wrote */
+ val = ntb_spad_read(ndev, VERSION);
+ if (val != PERF_VERSION) {
+ dev_dbg(&pdev->dev, "Remote version = %#x\n", val);
+ goto out;
+ }
+
+ val = ntb_spad_read(ndev, MW_SZ_HIGH);
+ size = (u64)val << 32;
+
+ val = ntb_spad_read(ndev, MW_SZ_LOW);
+ size |= val;
+
+ dev_dbg(&pdev->dev, "Remote MW size = %#llx\n", size);
+
+ rc = perf_set_mw(perf, size);
+ if (rc)
+ goto out1;
+
+ perf->link_is_up = true;
+
+ return;
+
+out1:
+ perf_free_mw(perf);
+
+out:
+ if (ntb_link_is_up(ndev, NULL, NULL) == 1)
+ schedule_delayed_work(&perf->link_work,
+ msecs_to_jiffies(PERF_LINK_DOWN_TIMEOUT));
+}
+
+static void perf_link_cleanup(struct work_struct *work)
+{
+ struct perf_ctx *perf = container_of(work,
+ struct perf_ctx,
+ link_cleanup);
+
+ dev_dbg(&perf->ntb->pdev->dev, "%s called\n", __func__);
+
+ if (!perf->link_is_up)
+ cancel_delayed_work_sync(&perf->link_work);
+}
+
+static int perf_setup_mw(struct ntb_dev *ntb, struct perf_ctx *perf)
+{
+ struct perf_mw *mw;
+ int rc;
+
+ mw = &perf->mw;
+
+ rc = ntb_mw_get_range(ntb, 0, &mw->phys_addr, &mw->phys_size,
+ &mw->xlat_align, &mw->xlat_align_size);
+ if (rc)
+ return rc;
+
+ perf->mw.vbase = ioremap_wc(mw->phys_addr, mw->phys_size);
+ if (!mw->vbase)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static ssize_t debugfs_run_read(struct file *filp, char __user *ubuf,
+ size_t count, loff_t *offp)
+{
+ struct perf_ctx *perf = filp->private_data;
+ char *buf;
+ ssize_t ret, out_offset;
+
+ if (!perf)
+ return 0;
+
+ buf = kmalloc(64, GFP_KERNEL);
+ out_offset = snprintf(buf, 64, "%d\n", perf->run);
+ ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
+ kfree(buf);
+
+ return ret;
+}
+
+static ssize_t debugfs_run_write(struct file *filp, const char __user *ubuf,
+ size_t count, loff_t *offp)
+{
+ struct perf_ctx *perf = filp->private_data;
+ int node, i;
+
+ if (!perf->link_is_up)
+ return 0;
+
+ if (perf->perf_threads == 0)
+ return 0;
+
+ if (atomic_read(&perf->tsync) == 0)
+ perf->run = false;
+
+ if (perf->run) {
+ /* lets stop the threads */
+ perf->run = false;
+ for (i = 0; i < MAX_THREADS; i++) {
+ if (perf->pthr_ctx[i].thread) {
+ kthread_stop(perf->pthr_ctx[i].thread);
+ perf->pthr_ctx[i].thread = NULL;
+ } else
+ break;
+ }
+ } else {
+ perf->run = true;
+
+ if (perf->perf_threads > MAX_THREADS) {
+ perf->perf_threads = MAX_THREADS;
+ pr_info("Reset total threads to: %u\n", MAX_THREADS);
+ }
+
+ /* no greater than 1M */
+ if (seg_order > MAX_SEG_ORDER) {
+ seg_order = MAX_SEG_ORDER;
+ pr_info("Fix seg_order to %u\n", seg_order);
+ }
+
+ if (run_order < seg_order) {
+ run_order = seg_order;
+ pr_info("Fix run_order to %u\n", run_order);
+ }
+
+ node = dev_to_node(&perf->ntb->pdev->dev);
+ /* launch kernel thread */
+ for (i = 0; i < perf->perf_threads; i++) {
+ struct pthr_ctx *pctx;
+
+ pctx = &perf->pthr_ctx[i];
+ atomic_set(&pctx->dma_sync, 0);
+ pctx->perf = perf;
+ pctx->thread =
+ kthread_create_on_node(ntb_perf_thread,
+ (void *)pctx,
+ node, "ntb_perf %d", i);
+ if (pctx->thread)
+ wake_up_process(pctx->thread);
+ else {
+ perf->run = false;
+ for (i = 0; i < MAX_THREADS; i++) {
+ if (pctx->thread) {
+ kthread_stop(pctx->thread);
+ pctx->thread = NULL;
+ }
+ }
+ }
+
+ if (perf->run == false)
+ return -ENXIO;
+ }
+
+ }
+
+ return count;
+}
+
+static const struct file_operations ntb_perf_debugfs_run = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = debugfs_run_read,
+ .write = debugfs_run_write,
+};
+
+static int perf_debugfs_setup(struct perf_ctx *perf)
+{
+ struct pci_dev *pdev = perf->ntb->pdev;
+
+ if (!debugfs_initialized())
+ return -ENODEV;
+
+ if (!perf_debugfs_dir) {
+ perf_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
+ if (!perf_debugfs_dir)
+ return -ENODEV;
+ }
+
+ perf->debugfs_node_dir = debugfs_create_dir(pci_name(pdev),
+ perf_debugfs_dir);
+ if (!perf->debugfs_node_dir)
+ return -ENODEV;
+
+ perf->debugfs_run = debugfs_create_file("run", S_IRUSR | S_IWUSR,
+ perf->debugfs_node_dir, perf,
+ &ntb_perf_debugfs_run);
+ if (!perf->debugfs_run)
+ return -ENODEV;
+
+ perf->debugfs_threads = debugfs_create_u8("threads", S_IRUSR | S_IWUSR,
+ perf->debugfs_node_dir,
+ &perf->perf_threads);
+ if (!perf->debugfs_threads)
+ return -ENODEV;
+
+ return 0;
+}
+
+static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb)
+{
+ struct pci_dev *pdev = ntb->pdev;
+ struct perf_ctx *perf;
+ int node;
+ int rc = 0;
+
+ node = dev_to_node(&pdev->dev);
+
+ perf = kzalloc_node(sizeof(*perf), GFP_KERNEL, node);
+ if (!perf) {
+ rc = -ENOMEM;
+ goto err_perf;
+ }
+
+ perf->ntb = ntb;
+ perf->perf_threads = 1;
+ atomic_set(&perf->tsync, 0);
+ perf->run = false;
+ spin_lock_init(&perf->db_lock);
+ perf_setup_mw(ntb, perf);
+ INIT_DELAYED_WORK(&perf->link_work, perf_link_work);
+ INIT_WORK(&perf->link_cleanup, perf_link_cleanup);
+
+ rc = ntb_set_ctx(ntb, perf, &perf_ops);
+ if (rc)
+ goto err_ctx;
+
+ perf->link_is_up = false;
+ ntb_link_enable(ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
+ ntb_link_event(ntb);
+
+ rc = perf_debugfs_setup(perf);
+ if (rc)
+ goto err_ctx;
+
+ return 0;
+
+err_ctx:
+ cancel_delayed_work_sync(&perf->link_work);
+ cancel_work_sync(&perf->link_cleanup);
+ kfree(perf);
+err_perf:
+ return rc;
+}
+
+static void perf_remove(struct ntb_client *client, struct ntb_dev *ntb)
+{
+ struct perf_ctx *perf = ntb->ctx;
+ int i;
+
+ dev_dbg(&perf->ntb->dev, "%s called\n", __func__);
+
+ cancel_delayed_work_sync(&perf->link_work);
+ cancel_work_sync(&perf->link_cleanup);
+
+ ntb_clear_ctx(ntb);
+ ntb_link_disable(ntb);
+
+ debugfs_remove_recursive(perf_debugfs_dir);
+ perf_debugfs_dir = NULL;
+
+ if (use_dma) {
+ for (i = 0; i < MAX_THREADS; i++) {
+ struct pthr_ctx *pctx = &perf->pthr_ctx[i];
+
+ if (pctx->dma_chan)
+ dma_release_channel(pctx->dma_chan);
+ }
+ }
+
+ kfree(perf);
+}
+
+static struct ntb_client perf_client = {
+ .ops = {
+ .probe = perf_probe,
+ .remove = perf_remove,
+ },
+};
+module_ntb_client(perf_client);