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    SubjectRe: [PATCH v2 06/15] NTB: ntb_perf: Add full multi-port NTB API support
    On Sun, Dec 3, 2017 at 2:17 PM, Serge Semin <fancer.lancer@gmail.com> wrote:
    > NTB API has been updated to support multi-port devices like IDT
    > 89HPESx series or Microsemi Switchtec. Message registers
    > functionality has also been added to new API. In order to keep
    > the new hardware and corresponding capabilities well tested, NTB
    > performance driver is accordingly altered.
    >
    > Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
    > ---
    >
    > Changelog v1:
    > - Alter interface in compliance with multi-port API
    > - Create Scratchpads and Message compliant NTB link init process
    > - Simplify memcpy and DMA-based tests process
    > - Limit DebugFS access methods to prevent the driver failure
    >
    > Changelog v2:
    > - Remove driver Author/Description/License macros
    > - Replace magic numbers with macros
    > - Fix global index calc error for devices with highest port index
    > - Fix invalid scratchpad selection in send_msg algorithm
    > - Fix bytes order translation in message recv method
    > - Use local global index to select an inbound MW
    > - Add commands send/recv/exec debug prints
    > - Call ntb_mw_get_align when link is supposed to be up
    >
    > drivers/ntb/test/ntb_perf.c | 1826 +++++++++++++++++++++++++++++--------------
    > 1 file changed, 1222 insertions(+), 604 deletions(-)
    >
    > diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c
    > index 427112cf101a..5ca5cc6f9687 100644
    > --- a/drivers/ntb/test/ntb_perf.c
    > +++ b/drivers/ntb/test/ntb_perf.c
    > @@ -5,6 +5,7 @@
    > * GPL LICENSE SUMMARY
    > *
    > * Copyright(c) 2015 Intel Corporation. All rights reserved.
    > + * Copyright(c) 2017 T-Platforms. 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
    > @@ -13,6 +14,7 @@
    > * BSD LICENSE
    > *
    > * Copyright(c) 2015 Intel Corporation. All rights reserved.
    > + * Copyright(c) 2017 T-Platforms. All Rights Reserved.
    > *
    > * Redistribution and use in source and binary forms, with or without
    > * modification, are permitted provided that the following conditions
    > @@ -40,860 +42,1476 @@
    > * (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
    > + * PCIe NTB Perf Linux driver
    > + *
    > + * Contact Information:
    > + * Dave Jiang <dave.jiang@intel.com>
    > + * Serge Semin <fancer.lancer@gmail.com>, <Sergey.Semin@t-platforms.ru>
    > + */
    > +
    > +/*
    > + * How to use this tool, by example.
    > + *
    > + * Assuming $DBG_DIR is something like:
    > + * '/sys/kernel/debug/ntb_perf/0000:00:03.0'
    > + * Suppose aside from local device there is at least one remote device
    > + * connected to NTB with index 0.
    > + *-----------------------------------------------------------------------------
    > + * Eg: install driver with specified chunk/total orders and dma-enabled flag
    > + *
    > + * root@self# insmod ntb_perf.ko chunk_order=19 total_order=28 use_dma
    > + *-----------------------------------------------------------------------------
    > + * Eg: check NTB ports (index) and MW mapping information
    > + *
    > + * root@self# cat $DBG_DIR/info
    > + *-----------------------------------------------------------------------------
    > + * Eg: start performance test with peer (index 0) and get the test metrics
    > + *
    > + * root@self# echo 0 > $DBG_DIR/run
    > + * root@self# cat $DBG_DIR/run
    > */
    >
    > #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/sched.h>
    > +#include <linux/wait.h>
    > #include <linux/dma-mapping.h>
    > +#include <linux/dmaengine.h>
    > #include <linux/pci.h>
    > +#include <linux/ktime.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/workqueue.h>
    > +#include <linux/debugfs.h>
    > +#include <linux/random.h>
    > #include <linux/ntb.h>
    > -#include <linux/mutex.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 msecs_to_jiffies(50)
    > -#define DMA_RETRIES 20
    > -#define SZ_4G (1ULL << 32)
    > -#define MAX_SEG_ORDER 20 /* no larger than 1M for kmalloc buffer */
    > -#define PIDX NTB_DEF_PEER_IDX
    > -
    > -MODULE_LICENSE(DRIVER_LICENSE);
    > +#define DRIVER_VERSION "2.0"
    > +
    > +MODULE_LICENSE("Dual BSD/GPL");
    > MODULE_VERSION(DRIVER_VERSION);
    > -MODULE_AUTHOR(DRIVER_AUTHOR);
    > -MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
    > +MODULE_AUTHOR("Dave Jiang <dave.jiang@intel.com>");
    > +MODULE_DESCRIPTION("PCIe NTB Performance Measurement Tool");
    >
    > -static struct dentry *perf_debugfs_dir;
    > +#define MAX_THREADS_CNT 32
    > +#define DEF_THREADS_CNT 1
    > +#define MAX_CHUNK_SIZE SZ_1M
    > +#define MAX_CHUNK_ORDER 20 /* no larger than 1M */
    > +
    > +#define DMA_TRIES 100
    > +#define DMA_MDELAY 10
    > +
    > +#define MSG_TRIES 500
    > +#define MSG_UDELAY_LOW 1000
    > +#define MSG_UDELAY_HIGH 2000
    >
    > static unsigned long max_mw_size;
    > module_param(max_mw_size, ulong, 0644);
    > -MODULE_PARM_DESC(max_mw_size, "Limit size of large memory windows");
    > +MODULE_PARM_DESC(max_mw_size, "Upper limit of memory window size");
    >
    > -static unsigned int seg_order = 19; /* 512K */
    > -module_param(seg_order, uint, 0644);
    > -MODULE_PARM_DESC(seg_order, "size order [2^n] of buffer segment for testing");
    > +static unsigned char chunk_order = 19; /* 512K */
    > +module_param(chunk_order, byte, 0644);
    > +MODULE_PARM_DESC(chunk_order, "Data chunk order [2^n] to transfer");
    >
    > -static unsigned int run_order = 32; /* 4G */
    > -module_param(run_order, uint, 0644);
    > -MODULE_PARM_DESC(run_order, "size order [2^n] of total data to transfer");
    > +static unsigned char total_order = 30; /* 1G */
    > +module_param(total_order, byte, 0644);
    > +MODULE_PARM_DESC(total_order, "Total data order [2^n] 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");
    > -
    > -static bool on_node = true; /* default to 1 */
    > -module_param(on_node, bool, 0644);
    > -MODULE_PARM_DESC(on_node, "Run threads only on NTB device node (default: true)");
    > -
    > -struct perf_mw {
    > - phys_addr_t phys_addr;
    > - resource_size_t phys_size;
    > - void __iomem *vbase;
    > - size_t xlat_size;
    > - size_t buf_size;
    > - void *virt_addr;
    > - dma_addr_t dma_addr;
    > +MODULE_PARM_DESC(use_dma, "Use DMA engine to measure performance");
    > +
    > +/*==============================================================================
    > + * Perf driver data definition
    > + *==============================================================================
    > + */
    > +
    > +enum perf_cmd {
    > + PERF_CMD_INVAL = -1,/* invalid spad command */
    > + PERF_CMD_SSIZE = 0, /* send out buffer size */
    > + PERF_CMD_RSIZE = 1, /* recv in buffer size */
    > + PERF_CMD_SXLAT = 2, /* send in buffer xlat */
    > + PERF_CMD_RXLAT = 3, /* recv out buffer xlat */
    > + PERF_CMD_CLEAR = 4, /* clear allocated memory */
    > + PERF_STS_DONE = 5, /* init is done */
    > + PERF_STS_LNKUP = 6, /* link up state flag */
    > };
    >
    > 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];
    > - wait_queue_head_t *wq;
    > - int status;
    > - u64 copied;
    > - u64 diff_us;
    > +struct perf_peer {
    > + struct perf_ctx *perf;
    > + int pidx;
    > + int gidx;
    > +
    > + /* Outbound MW params */
    > + u64 outbuf_xlat;
    > + resource_size_t outbuf_size;
    > + void __iomem *outbuf;
    > +
    > + /* Inbound MW params */
    > + dma_addr_t inbuf_xlat;
    > + resource_size_t inbuf_size;
    > + void *inbuf;
    > +
    > + /* NTB connection setup service */
    > + struct work_struct service;
    > + unsigned long sts;
    > };
    > +#define to_peer_service(__work) \
    > + container_of(__work, struct perf_peer, service)
    >
    > -struct perf_ctx {
    > - struct ntb_dev *ntb;
    > - spinlock_t db_lock;
    > - struct perf_mw mw;
    > - bool link_is_up;
    > - struct delayed_work link_work;
    > - wait_queue_head_t link_wq;
    > - u8 perf_threads;
    > - /* mutex ensures only one set of threads run at once */
    > - struct mutex run_mutex;
    > - struct pthr_ctx pthr_ctx[MAX_THREADS];
    > - atomic_t tsync;
    > - atomic_t tdone;
    > +struct perf_thread {
    > + struct perf_ctx *perf;
    > + int tidx;
    > +
    > + /* DMA-based test sync parameters */
    > + atomic_t dma_sync;
    > + wait_queue_head_t dma_wait;
    > + struct dma_chan *dma_chan;
    > +
    > + /* Data source and measured statistics */
    > + void *src;
    > + u64 copied;
    > + ktime_t duration;
    > + int status;
    > + struct work_struct work;
    > };
    > +#define to_thread_work(__work) \
    > + container_of(__work, struct perf_thread, work)
    >
    > -enum {
    > - VERSION = 0,
    > - MW_SZ_HIGH,
    > - MW_SZ_LOW,
    > - MAX_SPAD
    > +struct perf_ctx {
    > + struct ntb_dev *ntb;
    > +
    > + /* Global device index and peers descriptors */
    > + int gidx;
    > + int pcnt;
    > + struct perf_peer *peers;
    > +
    > + /* Performance measuring work-threads interface */
    > + unsigned long busy_flag;
    > + wait_queue_head_t twait;
    > + atomic_t tsync;
    > + u8 tcnt;
    > + struct perf_peer *test_peer;
    > + struct perf_thread threads[MAX_THREADS_CNT];
    > +
    > + /* Scratchpad/Message IO operations */
    > + int (*cmd_send)(struct perf_peer *peer, enum perf_cmd cmd, u64 data);
    > + int (*cmd_recv)(struct perf_ctx *perf, int *pidx, enum perf_cmd *cmd,
    > + u64 *data);
    > +
    > + struct dentry *dbgfs_dir;
    > };
    >
    > +/*
    > + * Scratchpads-base commands interface
    > + */
    > +#define PERF_SPAD_CNT(_pcnt) \
    > + (3*((_pcnt) + 1))
    > +#define PERF_SPAD_CMD(_gidx) \
    > + (3*(_gidx))
    > +#define PERF_SPAD_LDATA(_gidx) \
    > + (3*(_gidx) + 1)
    > +#define PERF_SPAD_HDATA(_gidx) \
    > + (3*(_gidx) + 2)
    > +#define PERF_SPAD_NOTIFY(_gidx) \
    > + (BIT_ULL(_gidx))
    > +
    > +/*
    > + * Messages-base commands interface
    > + */
    > +#define PERF_MSG_CNT 3
    > +#define PERF_MSG_CMD 0
    > +#define PERF_MSG_LDATA 1
    > +#define PERF_MSG_HDATA 2
    > +
    > +/*==============================================================================
    > + * Static data declarations
    > + *==============================================================================
    > + */
    > +
    > +static struct dentry *perf_dbgfs_topdir;
    > +
    > +static struct workqueue_struct *perf_wq __read_mostly;
    > +
    > +/*==============================================================================
    > + * NTB cross-link commands execution service
    > + *==============================================================================
    > + */
    > +
    > +static void perf_terminate_test(struct perf_ctx *perf);
    > +
    > +static inline bool perf_link_is_up(struct perf_peer *peer)
    > +{
    > + u64 link;
    > +
    > + link = ntb_link_is_up(peer->perf->ntb, NULL, NULL);
    > + return !!(link & BIT_ULL_MASK(peer->pidx));
    > +}
    > +
    > +static int perf_spad_cmd_send(struct perf_peer *peer, enum perf_cmd cmd,
    > + u64 data)
    > +{
    > + struct perf_ctx *perf = peer->perf;
    > + int try;
    > + u32 sts;
    > +
    > + dev_dbg(&perf->ntb->dev, "CMD send: %d 0x%llx\n", cmd, data);
    > +
    > + /*
    > + * Perform predefined number of attempts before give up.
    > + * We are sending the data to the port specific scratchpad, so
    > + * to prevent a multi-port access race-condition. Additionally
    > + * there is no need in local locking since only thread-safe
    > + * service work is using this method.
    > + */
    > + for (try = 0; try < MSG_TRIES; try++) {
    > + if (!perf_link_is_up(peer))
    > + return -ENOLINK;
    > +
    > + sts = ntb_peer_spad_read(perf->ntb, peer->pidx,
    > + PERF_SPAD_CMD(perf->gidx));
    > + if (le32_to_cpu(sts) != PERF_CMD_INVAL) {
    > + usleep_range(MSG_UDELAY_LOW, MSG_UDELAY_HIGH);
    > + continue;
    > + }
    > +
    > + ntb_peer_spad_write(perf->ntb, peer->pidx,
    > + PERF_SPAD_LDATA(perf->gidx),
    > + cpu_to_le32(lower_32_bits(data)));
    > + ntb_peer_spad_write(perf->ntb, peer->pidx,
    > + PERF_SPAD_HDATA(perf->gidx),
    > + cpu_to_le32(upper_32_bits(data)));
    > + mmiowb();
    > + ntb_peer_spad_write(perf->ntb, peer->pidx,
    > + PERF_SPAD_CMD(perf->gidx),
    > + cpu_to_le32(cmd));
    > + mmiowb();
    > + ntb_peer_db_set(perf->ntb, PERF_SPAD_NOTIFY(peer->gidx));
    > +
    > + dev_dbg(&perf->ntb->dev, "DB ring peer %#llx\n",
    > + PERF_SPAD_NOTIFY(peer->gidx));
    > +
    > + break;
    > + }
    > +
    > + return try < MSG_TRIES ? 0 : -EAGAIN;
    > +}
    > +
    > +static int perf_spad_cmd_recv(struct perf_ctx *perf, int *pidx,
    > + enum perf_cmd *cmd, u64 *data)
    > +{
    > + struct perf_peer *peer;
    > + u32 val;
    > +
    > + ntb_db_clear(perf->ntb, PERF_SPAD_NOTIFY(perf->gidx));
    > +
    > + /*
    > + * We start scanning all over, since cleared DB may have been set
    > + * by any peer. Yes, it makes peer with smaller index being
    > + * serviced with greater priority, but it's convenient for spad
    > + * and message code unification and simplicity.
    > + */
    > + for (*pidx = 0; *pidx < perf->pcnt; (*pidx)++) {
    > + peer = &perf->peers[*pidx];
    > +
    > + if (!perf_link_is_up(peer))
    > + continue;
    > +
    > + val = ntb_spad_read(perf->ntb, PERF_SPAD_CMD(peer->gidx));
    > + val = le32_to_cpu(val);
    > + if (val == PERF_CMD_INVAL)
    > + continue;
    > +
    > + *cmd = val;
    > +
    > + val = ntb_spad_read(perf->ntb, PERF_SPAD_LDATA(peer->gidx));
    > + *data = le32_to_cpu(val);
    > +
    > + val = ntb_spad_read(perf->ntb, PERF_SPAD_HDATA(peer->gidx));
    > + *data |= (u64)le32_to_cpu(val) << 32;
    > +
    > + /* Next command can be retrieved from now */
    > + ntb_spad_write(perf->ntb, PERF_SPAD_CMD(peer->gidx),
    > + cpu_to_le32(PERF_CMD_INVAL));
    > +
    > + dev_dbg(&perf->ntb->dev, "CMD recv: %d 0x%llx\n", *cmd, *data);
    > +
    > + return 0;
    > + }
    > +
    > + return -ENODATA;
    > +}
    > +
    > +static int perf_msg_cmd_send(struct perf_peer *peer, enum perf_cmd cmd,
    > + u64 data)
    > +{
    > + struct perf_ctx *perf = peer->perf;
    > + int try, ret;
    > + u64 outbits;
    > +
    > + dev_dbg(&perf->ntb->dev, "CMD send: %d 0x%llx\n", cmd, data);
    > +
    > + /*
    > + * Perform predefined number of attempts before give up. Message
    > + * registers are free of race-condition problem when accessed
    > + * from different ports, so we don't need splitting registers
    > + * by global device index. We also won't have local locking,
    > + * since the method is used from service work only.
    > + */
    > + outbits = ntb_msg_outbits(perf->ntb);
    > + for (try = 0; try < MSG_TRIES; try++) {
    > + if (!perf_link_is_up(peer))
    > + return -ENOLINK;
    > +
    > + ret = ntb_msg_clear_sts(perf->ntb, outbits);
    > + if (ret)
    > + return ret;
    > +
    > + ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_LDATA,
    > + cpu_to_le32(lower_32_bits(data)));
    > +
    > + if (ntb_msg_read_sts(perf->ntb) & outbits) {
    > + usleep_range(MSG_UDELAY_LOW, MSG_UDELAY_HIGH);
    > + continue;
    > + }
    > +
    > + ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_HDATA,
    > + cpu_to_le32(upper_32_bits(data)));
    > + mmiowb();
    > +
    > + /* This call shall trigger peer message event */
    > + ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_CMD,
    > + cpu_to_le32(cmd));
    > +
    > + break;
    > + }
    > +
    > + return try < MSG_TRIES ? 0 : -EAGAIN;
    > +}
    > +
    > +static int perf_msg_cmd_recv(struct perf_ctx *perf, int *pidx,
    > + enum perf_cmd *cmd, u64 *data)
    > +{
    > + u64 inbits;
    > + u32 val;
    > +
    > + inbits = ntb_msg_inbits(perf->ntb);
    > +
    > + if (hweight64(ntb_msg_read_sts(perf->ntb) & inbits) < 3)
    > + return -ENODATA;
    > +
    > + val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_CMD);
    > + *cmd = le32_to_cpu(val);
    > +
    > + val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_LDATA);
    > + *data = le32_to_cpu(val);
    > +
    > + val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_HDATA);
    > + *data |= (u64)le32_to_cpu(val) << 32;
    > +
    > + /* Next command can be retrieved from now */
    > + ntb_msg_clear_sts(perf->ntb, inbits);
    > +
    > + dev_dbg(&perf->ntb->dev, "CMD recv: %d 0x%llx\n", *cmd, *data);
    > +
    > + return 0;
    > +}
    > +
    > +static int perf_cmd_send(struct perf_peer *peer, enum perf_cmd cmd, u64 data)
    > +{
    > + struct perf_ctx *perf = peer->perf;
    > +
    > + if (cmd == PERF_CMD_SSIZE || cmd == PERF_CMD_SXLAT)
    > + return perf->cmd_send(peer, cmd, data);
    > +
    > + dev_err(&perf->ntb->dev, "Send invalid command\n");
    > + return -EINVAL;
    > +}
    > +
    > +static int perf_cmd_exec(struct perf_peer *peer, enum perf_cmd cmd)
    > +{
    > + switch (cmd) {
    > + case PERF_CMD_SSIZE:
    > + case PERF_CMD_RSIZE:
    > + case PERF_CMD_SXLAT:
    > + case PERF_CMD_RXLAT:
    > + case PERF_CMD_CLEAR:
    > + break;
    > + default:
    > + dev_err(&peer->perf->ntb->dev, "Exec invalid command\n");
    > + return -EINVAL;
    > + }
    > +
    > + /* No need of memory barrier, since bit ops have invernal lock */
    > + set_bit(cmd, &peer->sts);
    > +
    > + dev_dbg(&peer->perf->ntb->dev, "CMD exec: %d\n", cmd);
    > +
    > + (void)queue_work(system_highpri_wq, &peer->service);

    Seems like this should be the return value of this function, isntead
    of using a cast to ignore it. Am I missing something?

    > +
    > + return 0;
    > +}
    > +
    > +static int perf_cmd_recv(struct perf_ctx *perf)
    > +{
    > + struct perf_peer *peer;
    > + int ret, pidx, cmd;
    > + u64 data;
    > +
    > + while (!(ret = perf->cmd_recv(perf, &pidx, &cmd, &data))) {
    > + peer = &perf->peers[pidx];
    > +
    > + switch (cmd) {
    > + case PERF_CMD_SSIZE:
    > + peer->inbuf_size = data;
    > + return perf_cmd_exec(peer, PERF_CMD_RSIZE);
    > + case PERF_CMD_SXLAT:
    > + peer->outbuf_xlat = data;
    > + return perf_cmd_exec(peer, PERF_CMD_RXLAT);
    > + default:
    > + dev_err(&perf->ntb->dev, "Recv invalid command\n");
    > + return -EINVAL;
    > + }
    > + }
    > +
    > + return ret == -ENODATA ? 0 : ret;

    Add a comment here explaining that no data came in, and that's ok :)
    Otherwise you'll have someone staring at it for 5 mins unnecessarily

    > +}
    > +
    > static void perf_link_event(void *ctx)
    > {
    > struct perf_ctx *perf = ctx;
    > + struct perf_peer *peer;
    > + bool lnk_up;
    > + int pidx;
    >
    > - if (ntb_link_is_up(perf->ntb, NULL, NULL) == 1) {
    > - schedule_delayed_work(&perf->link_work, 2*HZ);
    > - } else {
    > - dev_dbg(&perf->ntb->pdev->dev, "link down\n");
    > + for (pidx = 0; pidx < perf->pcnt; pidx++) {
    > + peer = &perf->peers[pidx];
    >
    > - if (!perf->link_is_up)
    > - cancel_delayed_work_sync(&perf->link_work);
    > + lnk_up = perf_link_is_up(peer);
    >
    > - perf->link_is_up = false;
    > + if (lnk_up &&
    > + !test_and_set_bit(PERF_STS_LNKUP, &peer->sts)) {
    > + perf_cmd_exec(peer, PERF_CMD_SSIZE);
    > + } else if (!lnk_up &&
    > + test_and_clear_bit(PERF_STS_LNKUP, &peer->sts)) {
    > + perf_cmd_exec(peer, PERF_CMD_CLEAR);
    > + }
    > }
    > }
    >
    > 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, "DB vec %d mask %#llx bits %#llx\n", vec,
    > + ntb_db_vector_mask(perf->ntb, vec), ntb_db_read(perf->ntb));
    >
    > - dev_dbg(&perf->ntb->dev, "doorbell vec %d mask %#llx bits %#llx\n",
    > - vec, db_mask, db_bits);
    > + /* Just receive all available commands */
    > + (void)perf_cmd_recv(perf);

    Is this throwing an error if not cast? If so, can't we just make this
    a return type of void?
    Same for all casts below too

    > +}
    > +
    > +static void perf_msg_event(void *ctx)
    > +{
    > + struct perf_ctx *perf = ctx;
    > +
    > + dev_dbg(&perf->ntb->dev, "Msg status bits %#llx\n",
    > + ntb_msg_read_sts(perf->ntb));
    > +
    > + /* Messages are only sent one-by-one */
    > + (void)perf_cmd_recv(perf);
    > }
    >
    > static const struct ntb_ctx_ops perf_ops = {
    > .link_event = perf_link_event,
    > .db_event = perf_db_event,
    > + .msg_event = perf_msg_event
    > };
    >
    > -static void perf_copy_callback(void *data)
    > +static void perf_free_outbuf(struct perf_peer *peer)
    > +{
    > + (void)ntb_peer_mw_clear_trans(peer->perf->ntb, peer->pidx, peer->gidx);
    > +}
    > +
    > +static int perf_setup_outbuf(struct perf_peer *peer)
    > {
    > - struct pthr_ctx *pctx = data;
    > + struct perf_ctx *perf = peer->perf;
    > + int ret;
    > +
    > + /* Outbuf size can be unaligned due to custom max_mw_size */
    > + ret = ntb_peer_mw_set_trans(perf->ntb, peer->pidx, peer->gidx,
    > + peer->outbuf_xlat, peer->outbuf_size);
    > + if (ret) {
    > + dev_err(&perf->ntb->dev, "Failed to set outbuf translation\n");
    > + return ret;
    > + }
    > +
    > + /* Initialization is finally done */
    > + set_bit(PERF_STS_DONE, &peer->sts);
    >
    > - atomic_dec(&pctx->dma_sync);
    > + return 0;
    > }
    >
    > -static ssize_t perf_copy(struct pthr_ctx *pctx, char __iomem *dst,
    > - char *src, size_t size)
    > +static void perf_free_inbuf(struct perf_peer *peer)
    > {
    > - 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;
    > - void __iomem *vbase;
    > - void __iomem *dst_vaddr;
    > - dma_addr_t dst_phys;
    > - int retries = 0;
    > + if (!peer->inbuf)
    > + return;
    >
    > - if (!use_dma) {
    > - memcpy_toio(dst, src, size);
    > - return size;
    > + (void)ntb_mw_clear_trans(peer->perf->ntb, peer->pidx, peer->gidx);
    > + dma_free_coherent(&peer->perf->ntb->dev, peer->inbuf_size,
    > + peer->inbuf, peer->inbuf_xlat);
    > + peer->inbuf = NULL;
    > +}
    > +
    > +static int perf_setup_inbuf(struct perf_peer *peer)
    > +{
    > + resource_size_t xlat_align, size_align, size_max;
    > + struct perf_ctx *perf = peer->perf;
    > + int ret;
    > +
    > + /* Get inbound MW parameters */
    > + ret = ntb_mw_get_align(perf->ntb, peer->pidx, perf->gidx,
    > + &xlat_align, &size_align, &size_max);
    > + if (ret) {
    > + dev_err(&perf->ntb->dev, "Couldn't get inbuf restrictions\n");
    > + return ret;
    > }
    >
    > - if (!chan) {
    > - dev_err(&perf->ntb->dev, "DMA engine does not exist\n");
    > + if (peer->inbuf_size > size_max) {
    > + dev_err(&perf->ntb->dev, "Too big inbuf size %pa > %pa\n",
    > + &peer->inbuf_size, &size_max);
    > return -EINVAL;
    > }
    >
    > - device = chan->device;
    > - src_off = (uintptr_t)src & ~PAGE_MASK;
    > - dst_off = (uintptr_t __force)dst & ~PAGE_MASK;
    > + peer->inbuf_size = round_up(peer->inbuf_size, size_align);
    >
    > - if (!is_dma_copy_aligned(device, src_off, dst_off, size))
    > - return -ENODEV;
    > -
    > - vbase = mw->vbase;
    > - dst_vaddr = dst;
    > - dst_phys = mw->phys_addr + (dst_vaddr - vbase);
    > + perf_free_inbuf(peer);
    >
    > - unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT);
    > - if (!unmap)
    > + peer->inbuf = dma_alloc_coherent(&perf->ntb->dev, peer->inbuf_size,
    > + &peer->inbuf_xlat, GFP_KERNEL);
    > + if (!peer->inbuf) {
    > + dev_err(&perf->ntb->dev, "Failed to alloc inbuf of %pa\n",
    > + &peer->inbuf_size);
    > return -ENOMEM;
    > + }
    > + if (!IS_ALIGNED(peer->inbuf_xlat, xlat_align)) {
    > + dev_err(&perf->ntb->dev, "Unaligned inbuf allocated\n");
    > + goto err_free_inbuf;
    > + }
    >
    > - 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;
    > + ret = ntb_mw_set_trans(perf->ntb, peer->pidx, peer->gidx,
    > + peer->inbuf_xlat, peer->inbuf_size);
    > + if (ret) {
    > + dev_err(&perf->ntb->dev, "Failed to set inbuf translation\n");
    > + goto err_free_inbuf;
    > + }
    >
    > - unmap->to_cnt = 1;
    > + /*
    > + * We submit inbuf xlat transmission cmd for execution here to follow
    > + * the code architecture, even though this method is called from service
    > + * work itself so the command will be executed right after it returns.
    > + */
    > + (void)perf_cmd_exec(peer, PERF_CMD_SXLAT);
    >
    > - 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));
    > + return 0;
    >
    > - if (!txd) {
    > - pctx->dma_prep_err++;
    > - goto err_get_unmap;
    > - }
    > +err_free_inbuf:
    > + perf_free_inbuf(peer);
    >
    > - txd->callback = perf_copy_callback;
    > - txd->callback_param = pctx;
    > - dma_set_unmap(txd, unmap);
    > + return ret;
    > +}
    >
    > - cookie = dmaengine_submit(txd);
    > - if (dma_submit_error(cookie))
    > - goto err_set_unmap;
    > +static void perf_service_work(struct work_struct *work)
    > +{
    > + struct perf_peer *peer = to_peer_service(work);
    >
    > - dmaengine_unmap_put(unmap);
    > + if (test_and_clear_bit(PERF_CMD_SSIZE, &peer->sts))
    > + perf_cmd_send(peer, PERF_CMD_SSIZE, peer->outbuf_size);
    >
    > - atomic_inc(&pctx->dma_sync);
    > - dma_async_issue_pending(chan);
    > + if (test_and_clear_bit(PERF_CMD_RSIZE, &peer->sts))
    > + perf_setup_inbuf(peer);
    >
    > - return size;
    > + if (test_and_clear_bit(PERF_CMD_SXLAT, &peer->sts))
    > + perf_cmd_send(peer, PERF_CMD_SXLAT, peer->inbuf_xlat);
    >
    > -err_set_unmap:
    > - dmaengine_unmap_put(unmap);
    > -err_get_unmap:
    > - dmaengine_unmap_put(unmap);
    > - return 0;
    > -}
    > + if (test_and_clear_bit(PERF_CMD_RXLAT, &peer->sts))
    > + perf_setup_outbuf(peer);
    >
    > -static int perf_move_data(struct pthr_ctx *pctx, char __iomem *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 __iomem *tmp = dst;
    > - u64 perf, diff_us;
    > - ktime_t kstart, kstop, kdiff;
    > - unsigned long last_sleep = jiffies;
    > -
    > - 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 5s to prevent soft hang. */
    > - if (unlikely((jiffies - last_sleep) > 5 * HZ)) {
    > - last_sleep = jiffies;
    > - set_current_state(TASK_INTERRUPTIBLE);
    > - schedule_timeout(1);
    > + if (test_and_clear_bit(PERF_CMD_CLEAR, &peer->sts)) {
    > + clear_bit(PERF_STS_DONE, &peer->sts);
    > + if (test_bit(0, &peer->perf->busy_flag) &&
    > + peer == peer->perf->test_peer) {
    > + dev_warn(&peer->perf->ntb->dev,
    > + "Freeing while test on-fly\n");
    > + perf_terminate_test(peer->perf);
    > }
    > + perf_free_outbuf(peer);
    > + perf_free_inbuf(peer);
    > + }
    > +}
    >
    > - if (unlikely(kthread_should_stop()))
    > - break;
    > +static int perf_init_service(struct perf_ctx *perf)
    > +{
    > + u64 mask;
    > +
    > + if (ntb_peer_mw_count(perf->ntb) < perf->pcnt + 1) {
    > + dev_err(&perf->ntb->dev, "Not enough memory windows\n");
    > + return -EINVAL;
    > }
    >
    > - if (use_dma) {
    > - pr_debug("%s: All DMA descriptors submitted\n", current->comm);
    > - while (atomic_read(&pctx->dma_sync) != 0) {
    > - if (kthread_should_stop())
    > - break;
    > - msleep(20);
    > - }
    > + if (ntb_msg_count(perf->ntb) >= PERF_MSG_CNT) {
    > + perf->cmd_send = perf_msg_cmd_send;
    > + perf->cmd_recv = perf_msg_cmd_recv;
    > +
    > + dev_dbg(&perf->ntb->dev, "Message service initialized\n");
    > +
    > + return 0;
    > }
    >
    > - kstop = ktime_get();
    > - kdiff = ktime_sub(kstop, kstart);
    > - diff_us = ktime_to_us(kdiff);
    > + dev_dbg(&perf->ntb->dev, "Message service unsupported\n");
    >
    > - pr_debug("%s: copied %llu bytes\n", current->comm, copied);
    > + mask = GENMASK_ULL(perf->pcnt, 0);
    > + if (ntb_spad_count(perf->ntb) >= PERF_SPAD_CNT(perf->pcnt) &&
    > + (ntb_db_valid_mask(perf->ntb) & mask) == mask) {
    > + perf->cmd_send = perf_spad_cmd_send;
    > + perf->cmd_recv = perf_spad_cmd_recv;
    >
    > - pr_debug("%s: lasted %llu usecs\n", current->comm, diff_us);
    > + dev_dbg(&perf->ntb->dev, "Scratchpad service initialized\n");
    >
    > - perf = div64_u64(copied, diff_us);
    > + return 0;
    > + }
    >
    > - pr_debug("%s: MBytes/s: %llu\n", current->comm, perf);
    > + dev_dbg(&perf->ntb->dev, "Scratchpad service unsupported\n");
    >
    > - pctx->copied = copied;
    > - pctx->diff_us = diff_us;
    > + dev_err(&perf->ntb->dev, "Command services unsupported\n");
    >
    > - return 0;
    > + return -EINVAL;
    > }
    >
    > -static bool perf_dma_filter_fn(struct dma_chan *chan, void *node)
    > +static int perf_enable_service(struct perf_ctx *perf)
    > {
    > - /* Is the channel required to be on the same node as the device? */
    > - if (!on_node)
    > - return true;
    > + u64 mask, incmd_bit;
    > + int ret, sidx, scnt;
    >
    > - return dev_to_node(&chan->dev->device) == (int)(unsigned long)node;
    > -}
    > + mask = ntb_db_valid_mask(perf->ntb);
    > + (void)ntb_db_set_mask(perf->ntb, mask);
    >
    > -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 __iomem *dst;
    > - u64 win_size, buf_size, total;
    > - void *src;
    > - int rc, node, i;
    > - struct dma_chan *dma_chan = NULL;
    > + ret = ntb_set_ctx(perf->ntb, perf, &perf_ops);
    > + if (ret)
    > + return ret;
    >
    > - pr_debug("kthread %s starting...\n", current->comm);
    > + if (perf->cmd_send == perf_msg_cmd_send) {
    > + u64 inbits, outbits;
    >
    > - node = on_node ? dev_to_node(&pdev->dev) : NUMA_NO_NODE;
    > + inbits = ntb_msg_inbits(perf->ntb);
    > + outbits = ntb_msg_outbits(perf->ntb);
    > + (void)ntb_msg_set_mask(perf->ntb, inbits | outbits);
    >
    > - if (use_dma && !pctx->dma_chan) {
    > - dma_cap_mask_t dma_mask;
    > + incmd_bit = BIT_ULL(__ffs64(inbits));
    > + ret = ntb_msg_clear_mask(perf->ntb, incmd_bit);
    >
    > - 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;
    > + dev_dbg(&perf->ntb->dev, "MSG sts unmasked %#llx\n", incmd_bit);
    > + } else {
    > + scnt = ntb_spad_count(perf->ntb);
    > + for (sidx = 0; sidx < scnt; sidx++)
    > + ntb_spad_write(perf->ntb, sidx, PERF_CMD_INVAL);
    > + incmd_bit = PERF_SPAD_NOTIFY(perf->gidx);
    > + ret = ntb_db_clear_mask(perf->ntb, incmd_bit);
    > +
    > + dev_dbg(&perf->ntb->dev, "DB bits unmasked %#llx\n", incmd_bit);
    > + }
    > + if (ret) {
    > + ntb_clear_ctx(perf->ntb);
    > + return ret;
    > }
    >
    > - 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;
    > - }
    > + ntb_link_enable(perf->ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
    > + /* Might be not necessary */
    > + ntb_link_event(perf->ntb);
    > +
    > + return 0;
    > +}
    > +
    > +static void perf_disable_service(struct perf_ctx *perf)
    > +{
    > + int pidx;
    > +
    > + ntb_link_disable(perf->ntb);
    > +
    > + if (perf->cmd_send == perf_msg_cmd_send) {
    > + u64 inbits;
    > +
    > + inbits = ntb_msg_inbits(perf->ntb);
    > + (void)ntb_msg_set_mask(perf->ntb, inbits);
    > + } else {
    > + (void)ntb_db_set_mask(perf->ntb, PERF_SPAD_NOTIFY(perf->gidx));
    > }
    >
    > - win_size = mw->phys_size;
    > - buf_size = 1ULL << seg_order;
    > - total = 1ULL << run_order;
    > + ntb_clear_ctx(perf->ntb);
    >
    > - if (buf_size > MAX_TEST_SIZE)
    > - buf_size = MAX_TEST_SIZE;
    > + for (pidx = 0; pidx < perf->pcnt; pidx++)
    > + perf_cmd_exec(&perf->peers[pidx], PERF_CMD_CLEAR);
    >
    > - dst = (char __iomem *)mw->vbase;
    > + for (pidx = 0; pidx < perf->pcnt; pidx++)
    > + flush_work(&perf->peers[pidx].service);
    > +}
    >
    > - atomic_inc(&perf->tsync);
    > - while (atomic_read(&perf->tsync) != perf->perf_threads)
    > - schedule();
    > +/*==============================================================================
    > + * Performance measuring work-thread
    > + *==============================================================================
    > + */
    >
    > - src = pctx->srcs[pctx->src_idx];
    > - pctx->src_idx = (pctx->src_idx + 1) & (MAX_SRCS - 1);
    > +static void perf_dma_copy_callback(void *data)
    > +{
    > + struct perf_thread *pthr = data;
    >
    > - rc = perf_move_data(pctx, dst, src, buf_size, win_size, total);
    > + atomic_dec(&pthr->dma_sync);
    > + wake_up(&pthr->dma_wait);
    > +}
    >
    > - atomic_dec(&perf->tsync);
    > +static int perf_copy_chunk(struct perf_thread *pthr,
    > + void __iomem *dst, void *src, size_t len)
    > +{
    > + struct dma_async_tx_descriptor *tx;
    > + struct dmaengine_unmap_data *unmap;
    > + struct device *dma_dev;
    > + int try, ret = 0;
    >
    > - if (rc < 0) {
    > - pr_err("%s: failed\n", current->comm);
    > - rc = -ENXIO;
    > - goto err;
    > + if (!use_dma) {
    > + memcpy_toio(dst, src, len);
    > + goto ret_check_tsync;
    > }
    >
    > - for (i = 0; i < MAX_SRCS; i++) {
    > - kfree(pctx->srcs[i]);
    > - pctx->srcs[i] = NULL;
    > + dma_dev = pthr->dma_chan->device->dev;
    > +
    > + if (!is_dma_copy_aligned(pthr->dma_chan->device, offset_in_page(src),
    > + offset_in_page(dst), len))
    > + return -EIO;
    > +
    > + unmap = dmaengine_get_unmap_data(dma_dev, 2, GFP_NOWAIT);
    > + if (!unmap)
    > + return -ENOMEM;
    > +
    > + unmap->len = len;
    > + unmap->addr[0] = dma_map_page(dma_dev, virt_to_page(src),
    > + offset_in_page(src), len, DMA_TO_DEVICE);
    > + if (dma_mapping_error(dma_dev, unmap->addr[0])) {
    > + ret = -EIO;
    > + goto err_free_resource;
    > }
    > + unmap->to_cnt = 1;
    >
    > - atomic_inc(&perf->tdone);
    > - wake_up(pctx->wq);
    > - rc = 0;
    > - goto done;
    > + unmap->addr[1] = dma_map_page(dma_dev, virt_to_page(dst),
    > + offset_in_page(dst), len, DMA_FROM_DEVICE);
    > + if (dma_mapping_error(dma_dev, unmap->addr[1])) {
    > + ret = -EIO;
    > + goto err_free_resource;
    > + }
    > + unmap->from_cnt = 1;
    >
    > -err:
    > - for (i = 0; i < MAX_SRCS; i++) {
    > - kfree(pctx->srcs[i]);
    > - pctx->srcs[i] = NULL;
    > + do {
    > + tx = dmaengine_prep_dma_memcpy(pthr->dma_chan, unmap->addr[1],
    > + unmap->addr[0], len, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
    > + if (!tx)
    > + msleep(DMA_MDELAY);
    > + } while (!tx && (try++ < DMA_TRIES));
    > +
    > + if (!tx) {
    > + ret = -EIO;
    > + goto err_free_resource;
    > }
    >
    > - if (dma_chan) {
    > - dma_release_channel(dma_chan);
    > - pctx->dma_chan = NULL;
    > + tx->callback = perf_dma_copy_callback;
    > + tx->callback_param = pthr;
    > + dma_set_unmap(tx, unmap);
    > +
    > + if (dma_submit_error(dmaengine_submit(tx))) {
    > + dmaengine_unmap_put(unmap);
    > + goto err_free_resource;
    > }
    >
    > -done:
    > - /* Wait until we are told to stop */
    > - for (;;) {
    > - set_current_state(TASK_INTERRUPTIBLE);
    > - if (kthread_should_stop())
    > - break;
    > - schedule();
    > + dmaengine_unmap_put(unmap);
    > +
    > + atomic_inc(&pthr->dma_sync);
    > + dma_async_issue_pending(pthr->dma_chan);
    > +
    > +ret_check_tsync:
    > + return likely(atomic_read(&pthr->perf->tsync) > 0) ? 0 : -EINTR;
    > +
    > +err_free_resource:
    > + dmaengine_unmap_put(unmap);
    > +
    > + return ret;
    > +}
    > +
    > +static bool perf_dma_filter(struct dma_chan *chan, void *data)
    > +{
    > + struct perf_ctx *perf = data;
    > + int node;
    > +
    > + node = dev_to_node(&perf->ntb->dev);
    > +
    > + return node == NUMA_NO_NODE || node == dev_to_node(chan->device->dev);
    > +}
    > +
    > +static int perf_init_test(struct perf_thread *pthr)
    > +{
    > + struct perf_ctx *perf = pthr->perf;
    > + dma_cap_mask_t dma_mask;
    > +
    > + pthr->src = kmalloc_node(perf->test_peer->outbuf_size, GFP_KERNEL,
    > + dev_to_node(&perf->ntb->dev));
    > + if (!pthr->src)
    > + return -ENOMEM;
    > +
    > + get_random_bytes(pthr->src, perf->test_peer->outbuf_size);
    > +
    > + if (!use_dma)
    > + return 0;
    > +
    > + dma_cap_zero(dma_mask);
    > + dma_cap_set(DMA_MEMCPY, dma_mask);
    > + pthr->dma_chan = dma_request_channel(dma_mask, perf_dma_filter, perf);
    > + if (!pthr->dma_chan) {
    > + dev_err(&perf->ntb->dev, "%d: Failed to get DMA channel\n",
    > + pthr->tidx);
    > + atomic_dec(&perf->tsync);
    > + wake_up(&perf->twait);
    > + kfree(pthr->src);
    > + return -ENODEV;
    > }
    > - __set_current_state(TASK_RUNNING);
    >
    > - return rc;
    > + atomic_set(&pthr->dma_sync, 0);
    > +
    > + return 0;
    > }
    >
    > -static void perf_free_mw(struct perf_ctx *perf)
    > +static int perf_run_test(struct perf_thread *pthr)
    > {
    > - struct perf_mw *mw = &perf->mw;
    > - struct pci_dev *pdev = perf->ntb->pdev;
    > + struct perf_peer *peer = pthr->perf->test_peer;
    > + struct perf_ctx *perf = pthr->perf;
    > + void __iomem *flt_dst, *bnd_dst;
    > + u64 total_size, chunk_size;
    > + void *flt_src;
    > + int ret = 0;
    > +
    > + total_size = 1ULL << total_order;
    > + chunk_size = 1ULL << chunk_order;
    > + chunk_size = min_t(u64, peer->outbuf_size, chunk_size);
    > +
    > + flt_src = pthr->src;
    > + bnd_dst = peer->outbuf + peer->outbuf_size;
    > + flt_dst = peer->outbuf;
    > +
    > + pthr->duration = ktime_get();
    > +
    > + /* Copied field is cleared on test launch stage */
    > + while (pthr->copied < total_size) {
    > + ret = perf_copy_chunk(pthr, flt_dst, flt_src, chunk_size);
    > + if (ret) {
    > + dev_err(&perf->ntb->dev, "%d: Got error %d on test\n",
    > + pthr->tidx, ret);
    > + return ret;
    > + }
    >
    > - if (!mw->virt_addr)
    > - return;
    > + pthr->copied += chunk_size;
    >
    > - ntb_mw_clear_trans(perf->ntb, PIDX, 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;
    > + flt_dst += chunk_size;
    > + flt_src += chunk_size;
    > + if (flt_dst >= bnd_dst || flt_dst < peer->outbuf) {
    > + flt_dst = peer->outbuf;
    > + flt_src = pthr->src;
    > + }
    > +
    > + /* Give up CPU to give a chance for other threads to use it */
    > + schedule();
    > + }
    > +
    > + return 0;
    > }
    >
    > -static int perf_set_mw(struct perf_ctx *perf, resource_size_t size)
    > +static int perf_sync_test(struct perf_thread *pthr)
    > {
    > - struct perf_mw *mw = &perf->mw;
    > - size_t xlat_size, buf_size;
    > - resource_size_t xlat_align;
    > - resource_size_t xlat_align_size;
    > - int rc;
    > + struct perf_ctx *perf = pthr->perf;
    >
    > - if (!size)
    > - return -EINVAL;
    > + if (!use_dma)
    > + goto no_dma_ret;
    >
    > - rc = ntb_mw_get_align(perf->ntb, PIDX, 0, &xlat_align,
    > - &xlat_align_size, NULL);
    > - if (rc)
    > - return rc;
    > + wait_event(pthr->dma_wait,
    > + (atomic_read(&pthr->dma_sync) == 0 ||
    > + atomic_read(&perf->tsync) < 0));
    >
    > - xlat_size = round_up(size, xlat_align_size);
    > - buf_size = round_up(size, xlat_align);
    > + if (atomic_read(&perf->tsync) < 0)
    > + return -EINTR;
    >
    > - if (mw->xlat_size == xlat_size)
    > - return 0;
    > +no_dma_ret:
    > + pthr->duration = ktime_sub(ktime_get(), pthr->duration);
    > +
    > + dev_dbg(&perf->ntb->dev, "%d: copied %llu bytes\n",
    > + pthr->tidx, pthr->copied);
    >
    > - if (mw->buf_size)
    > - perf_free_mw(perf);
    > + dev_dbg(&perf->ntb->dev, "%d: lasted %llu usecs\n",
    > + pthr->tidx, ktime_to_us(pthr->duration));
    >
    > - mw->xlat_size = xlat_size;
    > - mw->buf_size = buf_size;
    > + dev_dbg(&perf->ntb->dev, "%d: %llu MBytes/s\n", pthr->tidx,
    > + div64_u64(pthr->copied, ktime_to_us(pthr->duration)));
    >
    > - 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_clear_test(struct perf_thread *pthr)
    > +{
    > + struct perf_ctx *perf = pthr->perf;
    > +
    > + if (!use_dma)
    > + goto no_dma_notify;
    > +
    > + /*
    > + * If test finished without errors, termination isn't needed.
    > + * We call it anyway just to be sure of the transfers completion.
    > + */
    > + (void)dmaengine_terminate_sync(pthr->dma_chan);
    > +
    > + dma_release_channel(pthr->dma_chan);
    > +
    > +no_dma_notify:
    > + atomic_dec(&perf->tsync);
    > + wake_up(&perf->twait);
    > + kfree(pthr->src);
    > +}
    > +
    > +static void perf_thread_work(struct work_struct *work)
    > +{
    > + struct perf_thread *pthr = to_thread_work(work);
    > + int ret;
    > +
    > + /*
    > + * Perform stages in compliance with use_dma flag value.
    > + * Test status is changed only if error happened, otherwise
    > + * status -ENODATA is kept while test is on-fly. Results
    > + * synchronization is performed only if test fininshed
    > + * without an error or interruption.
    > + */
    > + ret = perf_init_test(pthr);
    > + if (ret) {
    > + pthr->status = ret;
    > + return;
    > }
    >
    > - rc = ntb_mw_set_trans(perf->ntb, PIDX, 0, mw->dma_addr, mw->xlat_size);
    > - if (rc) {
    > - dev_err(&perf->ntb->dev, "Unable to set mw0 translation\n");
    > - perf_free_mw(perf);
    > - return -EIO;
    > + ret = perf_run_test(pthr);
    > + if (ret) {
    > + pthr->status = ret;
    > + goto err_clear_test;
    > }
    >
    > - return 0;
    > + pthr->status = perf_sync_test(pthr);
    > +
    > +err_clear_test:
    > + perf_clear_test(pthr);
    > }
    >
    > -static void perf_link_work(struct work_struct *work)
    > +static int perf_set_tcnt(struct perf_ctx *perf, u8 tcnt)
    > {
    > - 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;
    > + if (tcnt == 0 || tcnt > MAX_THREADS_CNT)
    > + return -EINVAL;
    >
    > - dev_dbg(&perf->ntb->pdev->dev, "%s called\n", __func__);
    > + if (test_and_set_bit_lock(0, &perf->busy_flag))
    > + return -EBUSY;
    >
    > - size = perf->mw.phys_size;
    > + perf->tcnt = tcnt;
    >
    > - if (max_mw_size && size > max_mw_size)
    > - size = max_mw_size;
    > + clear_bit_unlock(0, &perf->busy_flag);
    >
    > - ntb_peer_spad_write(ndev, PIDX, MW_SZ_HIGH, upper_32_bits(size));
    > - ntb_peer_spad_write(ndev, PIDX, MW_SZ_LOW, lower_32_bits(size));
    > - ntb_peer_spad_write(ndev, PIDX, VERSION, PERF_VERSION);
    > + return 0;
    > +}
    > +
    > +static void perf_terminate_test(struct perf_ctx *perf)
    > +{
    > + int tidx;
    > +
    > + atomic_set(&perf->tsync, -1);
    > + wake_up(&perf->twait);
    >
    > - /* 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;
    > + for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
    > + wake_up(&perf->threads[tidx].dma_wait);
    > + cancel_work_sync(&perf->threads[tidx].work);
    > }
    > +}
    >
    > - val = ntb_spad_read(ndev, MW_SZ_HIGH);
    > - size = (u64)val << 32;
    > +static int perf_submit_test(struct perf_peer *peer)
    > +{
    > + struct perf_ctx *perf = peer->perf;
    > + struct perf_thread *pthr;
    > + int tidx, ret;
    > +
    > + if (!test_bit(PERF_STS_DONE, &peer->sts))
    > + return -ENOLINK;
    >
    > - val = ntb_spad_read(ndev, MW_SZ_LOW);
    > - size |= val;
    > + if (test_and_set_bit_lock(0, &perf->busy_flag))
    > + return -EBUSY;
    >
    > - dev_dbg(&pdev->dev, "Remote MW size = %#llx\n", size);
    > + perf->test_peer = peer;
    > + atomic_set(&perf->tsync, perf->tcnt);
    >
    > - rc = perf_set_mw(perf, size);
    > - if (rc)
    > - goto out1;
    > + for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
    > + pthr = &perf->threads[tidx];
    >
    > - perf->link_is_up = true;
    > - wake_up(&perf->link_wq);
    > + pthr->status = -ENODATA;
    > + pthr->copied = 0;
    > + pthr->duration = ktime_set(0, 0);
    > + if (tidx < perf->tcnt)
    > + (void)queue_work(perf_wq, &pthr->work);
    > + }
    >
    > - return;
    > + ret = wait_event_interruptible(perf->twait,
    > + atomic_read(&perf->tsync) <= 0);
    > + if (ret == -ERESTARTSYS) {
    > + perf_terminate_test(perf);
    > + ret = -EINTR;
    > + }
    >
    > -out1:
    > - perf_free_mw(perf);
    > + clear_bit_unlock(0, &perf->busy_flag);
    >
    > -out:
    > - if (ntb_link_is_up(ndev, NULL, NULL) == 1)
    > - schedule_delayed_work(&perf->link_work,
    > - msecs_to_jiffies(PERF_LINK_DOWN_TIMEOUT));
    > + return ret;
    > }
    >
    > -static int perf_setup_mw(struct ntb_dev *ntb, struct perf_ctx *perf)
    > +static int perf_read_stats(struct perf_ctx *perf, char *buf,
    > + size_t size, ssize_t *pos)
    > {
    > - struct perf_mw *mw;
    > - int rc;
    > + struct perf_thread *pthr;
    > + int tidx;
    >
    > - mw = &perf->mw;
    > + if (test_and_set_bit_lock(0, &perf->busy_flag))
    > + return -EBUSY;
    >
    > - rc = ntb_peer_mw_get_addr(ntb, 0, &mw->phys_addr, &mw->phys_size);
    > - if (rc)
    > - return rc;
    > + (*pos) += scnprintf(buf + *pos, size - *pos,
    > + " Peer %d test statistics:\n", perf->test_peer->pidx);
    >
    > - perf->mw.vbase = ioremap_wc(mw->phys_addr, mw->phys_size);
    > - if (!mw->vbase)
    > - return -ENOMEM;
    > + for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
    > + pthr = &perf->threads[tidx];
    > +
    > + if (pthr->status == -ENODATA)
    > + continue;
    > +
    > + if (pthr->status) {
    > + (*pos) += scnprintf(buf + *pos, size - *pos,
    > + "%d: error status %d\n", tidx, pthr->status);
    > + continue;
    > + }
    > +
    > + (*pos) += scnprintf(buf + *pos, size - *pos,
    > + "%d: copied %llu bytes in %llu usecs, %llu MBytes/s\n",
    > + tidx, pthr->copied, ktime_to_us(pthr->duration),
    > + div64_u64(pthr->copied, ktime_to_us(pthr->duration)));
    > + }
    > +
    > + clear_bit_unlock(0, &perf->busy_flag);
    >
    > return 0;
    > }
    >
    > -static ssize_t debugfs_run_read(struct file *filp, char __user *ubuf,
    > - size_t count, loff_t *offp)
    > +static void perf_init_threads(struct perf_ctx *perf)
    > +{
    > + struct perf_thread *pthr;
    > + int tidx;
    > +
    > + perf->tcnt = DEF_THREADS_CNT;
    > + perf->test_peer = &perf->peers[0];
    > + init_waitqueue_head(&perf->twait);
    > +
    > + for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
    > + pthr = &perf->threads[tidx];
    > +
    > + pthr->perf = perf;
    > + pthr->tidx = tidx;
    > + pthr->status = -ENODATA;
    > + init_waitqueue_head(&pthr->dma_wait);
    > + INIT_WORK(&pthr->work, perf_thread_work);
    > + }
    > +}
    > +
    > +static void perf_clear_threads(struct perf_ctx *perf)
    > {
    > - struct perf_ctx *perf = filp->private_data;
    > + perf_terminate_test(perf);
    > +}
    > +
    > +/*==============================================================================
    > + * DebugFS nodes
    > + *==============================================================================
    > + */
    > +
    > +static ssize_t perf_dbgfs_read_info(struct file *filep, char __user *ubuf,
    > + size_t size, loff_t *offp)
    > +{
    > + struct perf_ctx *perf = filep->private_data;
    > + struct perf_peer *peer;
    > + size_t buf_size;
    > + ssize_t pos = 0;
    > + int ret, pidx;
    > char *buf;
    > - ssize_t ret, out_off = 0;
    > - struct pthr_ctx *pctx;
    > - int i;
    > - u64 rate;
    >
    > - if (!perf)
    > - return 0;
    > + buf_size = min_t(size_t, size, 0x1000U);
    >
    > - buf = kmalloc(1024, GFP_KERNEL);
    > + buf = kmalloc(buf_size, GFP_KERNEL);
    > if (!buf)
    > return -ENOMEM;
    >
    > - if (mutex_is_locked(&perf->run_mutex)) {
    > - out_off = scnprintf(buf, 64, "running\n");
    > - goto read_from_buf;
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + " Performance measuring tool info:\n\n");
    > +
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "Local port %d, Global index %d\n", ntb_port_number(perf->ntb),
    > + perf->gidx);
    > + pos += scnprintf(buf + pos, buf_size - pos, "Test status: ");
    > + if (test_bit(0, &perf->busy_flag)) {
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "on-fly with port %d (%d)\n",
    > + ntb_peer_port_number(perf->ntb, perf->test_peer->pidx),
    > + perf->test_peer->pidx);
    > + } else {
    > + pos += scnprintf(buf + pos, buf_size - pos, "idle\n");
    > }
    >
    > - for (i = 0; i < MAX_THREADS; i++) {
    > - pctx = &perf->pthr_ctx[i];
    > + for (pidx = 0; pidx < perf->pcnt; pidx++) {
    > + peer = &perf->peers[pidx];
    > +
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "Port %d (%d), Global index %d:\n",
    > + ntb_peer_port_number(perf->ntb, peer->pidx), peer->pidx,
    > + peer->gidx);
    > +
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "\tLink status: %s\n",
    > + test_bit(PERF_STS_LNKUP, &peer->sts) ? "up" : "down");
    > +
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "\tOut buffer addr 0x%pK\n", peer->outbuf);
    >
    > - if (pctx->status == -ENODATA)
    > - break;
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "\tOut buffer size %pa\n", &peer->outbuf_size);
    >
    > - if (pctx->status) {
    > - out_off += scnprintf(buf + out_off, 1024 - out_off,
    > - "%d: error %d\n", i,
    > - pctx->status);
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "\tOut buffer xlat 0x%016llx[p]\n", peer->outbuf_xlat);
    > +
    > + if (!peer->inbuf) {
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "\tIn buffer addr: unallocated\n");
    > continue;
    > }
    >
    > - rate = div64_u64(pctx->copied, pctx->diff_us);
    > - out_off += scnprintf(buf + out_off, 1024 - out_off,
    > - "%d: copied %llu bytes in %llu usecs, %llu MBytes/s\n",
    > - i, pctx->copied, pctx->diff_us, rate);
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "\tIn buffer addr 0x%pK\n", peer->inbuf);
    > +
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "\tIn buffer size %pa\n", &peer->inbuf_size);
    > +
    > + pos += scnprintf(buf + pos, buf_size - pos,
    > + "\tIn buffer xlat %pad[p]\n", &peer->inbuf_xlat);
    > }
    >
    > -read_from_buf:
    > - ret = simple_read_from_buffer(ubuf, count, offp, buf, out_off);
    > + ret = simple_read_from_buffer(ubuf, size, offp, buf, pos);
    > kfree(buf);
    >
    > return ret;
    > }
    >
    > -static void threads_cleanup(struct perf_ctx *perf)
    > +static const struct file_operations perf_dbgfs_info = {
    > + .open = simple_open,
    > + .read = perf_dbgfs_read_info
    > +};
    > +
    > +static ssize_t perf_dbgfs_read_run(struct file *filep, char __user *ubuf,
    > + size_t size, loff_t *offp)
    > {
    > - struct pthr_ctx *pctx;
    > - int i;
    > + struct perf_ctx *perf = filep->private_data;
    > + ssize_t ret, pos = 0;
    > + char *buf;
    >
    > - for (i = 0; i < MAX_THREADS; i++) {
    > - pctx = &perf->pthr_ctx[i];
    > - if (pctx->thread) {
    > - pctx->status = kthread_stop(pctx->thread);
    > - pctx->thread = NULL;
    > - }
    > - }
    > -}
    > + buf = kmalloc(1024, GFP_KERNEL);

    This size seems arbitrary. Either make it a #define or reference the
    actual size of what you are wanting.

    > + if (!buf)
    > + return -ENOMEM;
    >
    > -static void perf_clear_thread_status(struct perf_ctx *perf)
    > -{
    > - int i;
    > + ret = perf_read_stats(perf, buf, 1024, &pos);
    > + if (ret)
    > + goto err_free;
    > +
    > + ret = simple_read_from_buffer(ubuf, size, offp, buf, pos);
    > +err_free:
    > + kfree(buf);
    >
    > - for (i = 0; i < MAX_THREADS; i++)
    > - perf->pthr_ctx[i].status = -ENODATA;
    > + return ret;
    > }
    >
    > -static ssize_t debugfs_run_write(struct file *filp, const char __user *ubuf,
    > - size_t count, loff_t *offp)
    > +static ssize_t perf_dbgfs_write_run(struct file *filep, const char __user *ubuf,
    > + size_t size, loff_t *offp)
    > {
    > - struct perf_ctx *perf = filp->private_data;
    > - int node, i;
    > - DECLARE_WAIT_QUEUE_HEAD(wq);
    > + struct perf_ctx *perf = filep->private_data;
    > + struct perf_peer *peer;
    > + int pidx, ret;
    >
    > - if (wait_event_interruptible(perf->link_wq, perf->link_is_up))
    > - return -ENOLINK;
    > + ret = kstrtoint_from_user(ubuf, size, 0, &pidx);
    > + if (ret)
    > + return ret;
    >
    > - if (perf->perf_threads == 0)
    > + if (pidx < 0 || pidx >= perf->pcnt)
    > return -EINVAL;
    >
    > - if (!mutex_trylock(&perf->run_mutex))
    > - return -EBUSY;
    > + peer = &perf->peers[pidx];
    >
    > - perf_clear_thread_status(perf);
    > + ret = perf_submit_test(peer);
    > + if (ret)
    > + return ret;
    >
    > - if (perf->perf_threads > MAX_THREADS) {
    > - perf->perf_threads = MAX_THREADS;
    > - pr_info("Reset total threads to: %u\n", MAX_THREADS);
    > - }
    > + return size;
    > +}
    >
    > - /* 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);
    > - }
    > +static const struct file_operations perf_dbgfs_run = {
    > + .open = simple_open,
    > + .read = perf_dbgfs_read_run,
    > + .write = perf_dbgfs_write_run
    > +};
    >
    > - if (run_order < seg_order) {
    > - run_order = seg_order;
    > - pr_info("Fix run_order to %u\n", run_order);
    > - }
    > +static ssize_t perf_dbgfs_read_tcnt(struct file *filep, char __user *ubuf,
    > + size_t size, loff_t *offp)
    > +{
    > + struct perf_ctx *perf = filep->private_data;
    > + char buf[8];
    > + ssize_t pos;
    >
    > - node = on_node ? dev_to_node(&perf->ntb->pdev->dev)
    > - : NUMA_NO_NODE;
    > - atomic_set(&perf->tdone, 0);
    > + pos = scnprintf(buf, sizeof(buf), "%hhu\n", perf->tcnt);
    >
    > - /* launch kernel thread */
    > - for (i = 0; i < perf->perf_threads; i++) {
    > - struct pthr_ctx *pctx;
    > + return simple_read_from_buffer(ubuf, size, offp, buf, pos);
    > +}
    >
    > - pctx = &perf->pthr_ctx[i];
    > - atomic_set(&pctx->dma_sync, 0);
    > - pctx->perf = perf;
    > - pctx->wq = &wq;
    > - pctx->thread =
    > - kthread_create_on_node(ntb_perf_thread,
    > - (void *)pctx,
    > - node, "ntb_perf %d", i);
    > - if (IS_ERR(pctx->thread)) {
    > - pctx->thread = NULL;
    > - goto err;
    > - } else {
    > - wake_up_process(pctx->thread);
    > - }
    > - }
    > +static ssize_t perf_dbgfs_write_tcnt(struct file *filep,
    > + const char __user *ubuf,
    > + size_t size, loff_t *offp)
    > +{
    > + struct perf_ctx *perf = filep->private_data;
    > + int ret;
    > + u8 val;
    >
    > - wait_event_interruptible(wq,
    > - atomic_read(&perf->tdone) == perf->perf_threads);
    > + ret = kstrtou8_from_user(ubuf, size, 0, &val);
    > + if (ret)
    > + return ret;
    >
    > - threads_cleanup(perf);
    > - mutex_unlock(&perf->run_mutex);
    > - return count;
    > + ret = perf_set_tcnt(perf, val);
    > + if (ret)
    > + return ret;
    >
    > -err:
    > - threads_cleanup(perf);
    > - mutex_unlock(&perf->run_mutex);
    > - return -ENXIO;
    > + return size;
    > }
    >
    > -static const struct file_operations ntb_perf_debugfs_run = {
    > - .owner = THIS_MODULE,
    > +static const struct file_operations perf_dbgfs_tcnt = {
    > .open = simple_open,
    > - .read = debugfs_run_read,
    > - .write = debugfs_run_write,
    > + .read = perf_dbgfs_read_tcnt,
    > + .write = perf_dbgfs_write_tcnt
    > };
    >
    > -static int perf_debugfs_setup(struct perf_ctx *perf)
    > +static void perf_setup_dbgfs(struct perf_ctx *perf)
    > {
    > struct pci_dev *pdev = perf->ntb->pdev;
    > - struct dentry *debugfs_node_dir;
    > - struct dentry *debugfs_run;
    > - struct dentry *debugfs_threads;
    > - struct dentry *debugfs_seg_order;
    > - struct dentry *debugfs_run_order;
    > - struct dentry *debugfs_use_dma;
    > - struct dentry *debugfs_on_node;
    > -
    > - if (!debugfs_initialized())
    > - return -ENODEV;
    >
    > - /* Assumpion: only one NTB device in the system */
    > - if (!perf_debugfs_dir) {
    > - perf_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
    > - if (!perf_debugfs_dir)
    > - return -ENODEV;
    > - }
    > -
    > - debugfs_node_dir = debugfs_create_dir(pci_name(pdev),
    > - perf_debugfs_dir);
    > - if (!debugfs_node_dir)
    > - goto err;
    > -
    > - debugfs_run = debugfs_create_file("run", S_IRUSR | S_IWUSR,
    > - debugfs_node_dir, perf,
    > - &ntb_perf_debugfs_run);
    > - if (!debugfs_run)
    > - goto err;
    > -
    > - debugfs_threads = debugfs_create_u8("threads", S_IRUSR | S_IWUSR,
    > - debugfs_node_dir,
    > - &perf->perf_threads);
    > - if (!debugfs_threads)
    > - goto err;
    > -
    > - debugfs_seg_order = debugfs_create_u32("seg_order", 0600,
    > - debugfs_node_dir,
    > - &seg_order);
    > - if (!debugfs_seg_order)
    > - goto err;
    > -
    > - debugfs_run_order = debugfs_create_u32("run_order", 0600,
    > - debugfs_node_dir,
    > - &run_order);
    > - if (!debugfs_run_order)
    > - goto err;
    > -
    > - debugfs_use_dma = debugfs_create_bool("use_dma", 0600,
    > - debugfs_node_dir,
    > - &use_dma);
    > - if (!debugfs_use_dma)
    > - goto err;
    > -
    > - debugfs_on_node = debugfs_create_bool("on_node", 0600,
    > - debugfs_node_dir,
    > - &on_node);
    > - if (!debugfs_on_node)
    > - goto err;
    > + perf->dbgfs_dir = debugfs_create_dir(pci_name(pdev), perf_dbgfs_topdir);
    > + if (!perf->dbgfs_dir) {
    > + dev_warn(&perf->ntb->dev, "DebugFS unsupported\n");
    > + return;
    > + }
    > +
    > + debugfs_create_file("info", 0600, perf->dbgfs_dir, perf,
    > + &perf_dbgfs_info);
    >
    > - return 0;
    > + debugfs_create_file("run", 0600, perf->dbgfs_dir, perf,
    > + &perf_dbgfs_run);
    >
    > -err:
    > - debugfs_remove_recursive(perf_debugfs_dir);
    > - perf_debugfs_dir = NULL;
    > - return -ENODEV;
    > + debugfs_create_file("threads_count", 0600, perf->dbgfs_dir, perf,
    > + &perf_dbgfs_tcnt);
    > +
    > + /* They are made read-only for test exec safety and integrity */
    > + debugfs_create_u8("chunk_order", 0500, perf->dbgfs_dir, &chunk_order);
    > +
    > + debugfs_create_u8("total_order", 0500, perf->dbgfs_dir, &total_order);
    > +
    > + debugfs_create_bool("use_dma", 0500, perf->dbgfs_dir, &use_dma);
    > }
    >
    > -static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb)
    > +static void perf_clear_dbgfs(struct perf_ctx *perf)
    > +{
    > + debugfs_remove_recursive(perf->dbgfs_dir);
    > +}
    > +
    > +/*==============================================================================
    > + * Basic driver initialization
    > + *==============================================================================
    > + */
    > +
    > +static struct perf_ctx *perf_create_data(struct ntb_dev *ntb)
    > {
    > - struct pci_dev *pdev = ntb->pdev;
    > struct perf_ctx *perf;
    > - int node;
    > - int rc = 0;
    >
    > - if (ntb_spad_count(ntb) < MAX_SPAD) {
    > - dev_err(&ntb->dev, "Not enough scratch pad registers for %s",
    > - DRIVER_NAME);
    > - return -EIO;
    > - }
    > + perf = devm_kzalloc(&ntb->dev, sizeof(*perf), GFP_KERNEL);
    > + if (!perf)
    > + return ERR_PTR(-ENOMEM);
    >
    > - if (!ntb->ops->mw_set_trans) {
    > - dev_err(&ntb->dev, "Need inbound MW based NTB API\n");
    > - return -EINVAL;
    > + perf->pcnt = ntb_peer_port_count(ntb);
    > + perf->peers = devm_kcalloc(&ntb->dev, perf->pcnt, sizeof(*perf->peers),
    > + GFP_KERNEL);
    > + if (!perf->peers)
    > + return ERR_PTR(-ENOMEM);
    > +
    > + perf->ntb = ntb;
    > +
    > + return perf;
    > +}
    > +
    > +static int perf_setup_peer_mw(struct perf_peer *peer)
    > +{
    > + struct perf_ctx *perf = peer->perf;
    > + phys_addr_t phys_addr;
    > + int ret;
    > +
    > + /* Get outbound MW parameters and map it */
    > + ret = ntb_peer_mw_get_addr(perf->ntb, peer->gidx, &phys_addr,
    > + &peer->outbuf_size);
    > + if (ret)
    > + return ret;
    > +
    > + peer->outbuf = devm_ioremap_wc(&perf->ntb->dev, phys_addr,
    > + peer->outbuf_size);
    > + if (!peer->outbuf)
    > + return -ENOMEM;
    > +
    > + if (max_mw_size && peer->outbuf_size > max_mw_size) {
    > + peer->outbuf_size = max_mw_size;
    > + dev_warn(&peer->perf->ntb->dev,
    > + "Peer %d outbuf reduced to %#llx\n", peer->pidx,
    > + peer->outbuf_size);
    > }
    >
    > - if (ntb_peer_port_count(ntb) != NTB_DEF_PEER_CNT)
    > - dev_warn(&ntb->dev, "Multi-port NTB devices unsupported\n");
    > + return 0;
    > +}
    >
    > - node = on_node ? dev_to_node(&pdev->dev) : NUMA_NO_NODE;
    > - perf = kzalloc_node(sizeof(*perf), GFP_KERNEL, node);
    > - if (!perf) {
    > - rc = -ENOMEM;
    > - goto err_perf;
    > +static int perf_init_peers(struct perf_ctx *perf)
    > +{
    > + struct perf_peer *peer;
    > + int pidx, lport, ret;
    > +
    > + lport = ntb_port_number(perf->ntb);
    > + perf->gidx = -1;
    > + for (pidx = 0; pidx < perf->pcnt; pidx++) {
    > + peer = &perf->peers[pidx];
    > +
    > + peer->perf = perf;
    > + peer->pidx = pidx;
    > + if (lport < ntb_peer_port_number(perf->ntb, pidx)) {
    > + if (perf->gidx == -1)
    > + perf->gidx = pidx;
    > + peer->gidx = pidx + 1;
    > + } else {
    > + peer->gidx = pidx;
    > + }
    > + INIT_WORK(&peer->service, perf_service_work);
    > }
    > + if (perf->gidx == -1)
    > + perf->gidx = pidx;
    >
    > - perf->ntb = ntb;
    > - perf->perf_threads = 1;
    > - atomic_set(&perf->tsync, 0);
    > - mutex_init(&perf->run_mutex);
    > - spin_lock_init(&perf->db_lock);
    > - perf_setup_mw(ntb, perf);
    > - init_waitqueue_head(&perf->link_wq);
    > - INIT_DELAYED_WORK(&perf->link_work, perf_link_work);
    > + for (pidx = 0; pidx < perf->pcnt; pidx++) {
    > + ret = perf_setup_peer_mw(&perf->peers[pidx]);
    > + if (ret)
    > + return ret;
    > + }
    > +
    > + dev_dbg(&perf->ntb->dev, "Global port index %d\n", perf->gidx);
    > +
    > + return 0;
    > +}
    >
    > - rc = ntb_set_ctx(ntb, perf, &perf_ops);
    > - if (rc)
    > - goto err_ctx;
    > +static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb)
    > +{
    > + struct perf_ctx *perf;
    > + int ret;
    >
    > - perf->link_is_up = false;
    > - ntb_link_enable(ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
    > - ntb_link_event(ntb);
    > + perf = perf_create_data(ntb);
    > + if (IS_ERR(perf))
    > + return PTR_ERR(perf);
    >
    > - rc = perf_debugfs_setup(perf);
    > - if (rc)
    > - goto err_ctx;
    > + ret = perf_init_peers(perf);
    > + if (ret)
    > + return ret;
    >
    > - perf_clear_thread_status(perf);
    > + perf_init_threads(perf);
    >
    > - return 0;
    > + ret = perf_init_service(perf);
    > + if (ret)
    > + return ret;
    >
    > -err_ctx:
    > - cancel_delayed_work_sync(&perf->link_work);
    > - kfree(perf);
    > -err_perf:
    > - return rc;
    > + ret = perf_enable_service(perf);
    > + if (ret)
    > + return ret;
    > +
    > + perf_setup_dbgfs(perf);
    > +
    > + return 0;
    > }
    >
    > 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__);
    > + perf_clear_dbgfs(perf);
    >
    > - mutex_lock(&perf->run_mutex);
    > + perf_disable_service(perf);
    >
    > - cancel_delayed_work_sync(&perf->link_work);
    > + perf_clear_threads(perf);
    > +}
    >
    > - ntb_clear_ctx(ntb);
    > - ntb_link_disable(ntb);
    > +static struct ntb_client perf_client = {
    > + .ops = {
    > + .probe = perf_probe,
    > + .remove = perf_remove
    > + }
    > +};
    >
    > - debugfs_remove_recursive(perf_debugfs_dir);
    > - perf_debugfs_dir = NULL;
    > +static int __init perf_init(void)
    > +{
    > + int ret;
    >
    > - if (use_dma) {
    > - for (i = 0; i < MAX_THREADS; i++) {
    > - struct pthr_ctx *pctx = &perf->pthr_ctx[i];
    > + if (chunk_order > MAX_CHUNK_ORDER) {
    > + chunk_order = MAX_CHUNK_ORDER;
    > + pr_info("Chunk order reduced to %hhu\n", chunk_order);
    > + }
    >
    > - if (pctx->dma_chan)
    > - dma_release_channel(pctx->dma_chan);
    > - }
    > + if (total_order < chunk_order) {
    > + total_order = chunk_order;
    > + pr_info("Total data order reduced to %hhu\n", total_order);
    > }
    >
    > - kfree(perf);
    > + perf_wq = alloc_workqueue("perf_wq", WQ_UNBOUND | WQ_SYSFS, 0);
    > + if (!perf_wq)
    > + return -ENOMEM;
    > +
    > + if (debugfs_initialized())
    > + perf_dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
    > +
    > + ret = ntb_register_client(&perf_client);
    > + if (ret) {
    > + debugfs_remove_recursive(perf_dbgfs_topdir);
    > + destroy_workqueue(perf_wq);
    > + }
    > +
    > + return ret;
    > }
    > +module_init(perf_init);
    > +
    > +static void __exit perf_exit(void)
    > +{
    > + ntb_unregister_client(&perf_client);
    > + debugfs_remove_recursive(perf_dbgfs_topdir);
    > + destroy_workqueue(perf_wq);
    > +}
    > +module_exit(perf_exit);
    >
    > -static struct ntb_client perf_client = {
    > - .ops = {
    > - .probe = perf_probe,
    > - .remove = perf_remove,
    > - },
    > -};
    > -module_ntb_client(perf_client);
    > --
    > 2.12.0
    >

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      Last update: 2017-12-05 19:22    [W:6.370 / U:0.128 seconds]
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