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path: root/drivers/ntb/test/ntb_pingpong.c
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Diffstat (limited to 'drivers/ntb/test/ntb_pingpong.c')
-rw-r--r--drivers/ntb/test/ntb_pingpong.c450
1 files changed, 283 insertions, 167 deletions
diff --git a/drivers/ntb/test/ntb_pingpong.c b/drivers/ntb/test/ntb_pingpong.c
index 3f5a92bae6f8..65865e460ab8 100644
--- a/drivers/ntb/test/ntb_pingpong.c
+++ b/drivers/ntb/test/ntb_pingpong.c
@@ -1,10 +1,11 @@
/*
- * This file is provided under a dual BSD/GPLv2 license. When using or
+ * 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 EMC 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
@@ -18,6 +19,7 @@
* BSD LICENSE
*
* Copyright (C) 2015 EMC 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
@@ -46,37 +48,45 @@
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* PCIe NTB Pingpong Linux driver
- *
- * Contact Information:
- * Allen Hubbe <Allen.Hubbe@emc.com>
*/
-/* Note: load this module with option 'dyndbg=+p' */
+/*
+ * 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 delay between doorbell event and response
+ *
+ * root@self# insmod ntb_pingpong.ko delay_ms=1000
+ *-----------------------------------------------------------------------------
+ * Eg: get number of ping-pong cycles performed
+ *
+ * root@self# cat $DBG_DIR/count
+ */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/bitops.h>
-#include <linux/dma-mapping.h>
#include <linux/pci.h>
#include <linux/slab.h>
-#include <linux/spinlock.h>
+#include <linux/hrtimer.h>
#include <linux/debugfs.h>
#include <linux/ntb.h>
-#define DRIVER_NAME "ntb_pingpong"
-#define DRIVER_DESCRIPTION "PCIe NTB Simple Pingpong Client"
-
-#define DRIVER_LICENSE "Dual BSD/GPL"
-#define DRIVER_VERSION "1.0"
-#define DRIVER_RELDATE "24 March 2015"
-#define DRIVER_AUTHOR "Allen Hubbe <Allen.Hubbe@emc.com>"
+#define DRIVER_NAME "ntb_pingpong"
+#define DRIVER_VERSION "2.0"
-MODULE_LICENSE(DRIVER_LICENSE);
+MODULE_LICENSE("Dual BSD/GPL");
MODULE_VERSION(DRIVER_VERSION);
-MODULE_AUTHOR(DRIVER_AUTHOR);
-MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
+MODULE_AUTHOR("Allen Hubbe <Allen.Hubbe@emc.com>");
+MODULE_DESCRIPTION("PCIe NTB Simple Pingpong Client");
static unsigned int unsafe;
module_param(unsafe, uint, 0644);
@@ -86,237 +96,343 @@ static unsigned int delay_ms = 1000;
module_param(delay_ms, uint, 0644);
MODULE_PARM_DESC(delay_ms, "Milliseconds to delay the response to peer");
-static unsigned long db_init = 0x7;
-module_param(db_init, ulong, 0644);
-MODULE_PARM_DESC(db_init, "Initial doorbell bits to ring on the peer");
-
-/* Only two-ports NTB devices are supported */
-#define PIDX NTB_DEF_PEER_IDX
-
struct pp_ctx {
- struct ntb_dev *ntb;
- u64 db_bits;
- /* synchronize access to db_bits by ping and pong */
- spinlock_t db_lock;
- struct timer_list db_timer;
- unsigned long db_delay;
- struct dentry *debugfs_node_dir;
- struct dentry *debugfs_count;
- atomic_t count;
+ struct ntb_dev *ntb;
+ struct hrtimer timer;
+ u64 in_db;
+ u64 out_db;
+ int out_pidx;
+ u64 nmask;
+ u64 pmask;
+ atomic_t count;
+ spinlock_t lock;
+ struct dentry *dbgfs_dir;
};
+#define to_pp_timer(__timer) \
+ container_of(__timer, struct pp_ctx, timer)
-static struct dentry *pp_debugfs_dir;
+static struct dentry *pp_dbgfs_topdir;
-static void pp_ping(struct timer_list *t)
+static int pp_find_next_peer(struct pp_ctx *pp)
{
- struct pp_ctx *pp = from_timer(pp, t, db_timer);
- unsigned long irqflags;
- u64 db_bits, db_mask;
- u32 spad_rd, spad_wr;
+ u64 link, out_db;
+ int pidx;
+
+ link = ntb_link_is_up(pp->ntb, NULL, NULL);
+
+ /* Find next available peer */
+ if (link & pp->nmask) {
+ pidx = __ffs64(link & pp->nmask);
+ out_db = BIT_ULL(pidx + 1);
+ } else if (link & pp->pmask) {
+ pidx = __ffs64(link & pp->pmask);
+ out_db = BIT_ULL(pidx);
+ } else {
+ return -ENODEV;
+ }
- spin_lock_irqsave(&pp->db_lock, irqflags);
- {
- db_mask = ntb_db_valid_mask(pp->ntb);
- db_bits = ntb_db_read(pp->ntb);
+ spin_lock(&pp->lock);
+ pp->out_pidx = pidx;
+ pp->out_db = out_db;
+ spin_unlock(&pp->lock);
- if (db_bits) {
- dev_dbg(&pp->ntb->dev,
- "Masked pongs %#llx\n",
- db_bits);
- ntb_db_clear(pp->ntb, db_bits);
- }
+ return 0;
+}
- db_bits = ((pp->db_bits | db_bits) << 1) & db_mask;
+static void pp_setup(struct pp_ctx *pp)
+{
+ int ret;
- if (!db_bits)
- db_bits = db_init;
+ ntb_db_set_mask(pp->ntb, pp->in_db);
- spad_rd = ntb_spad_read(pp->ntb, 0);
- spad_wr = spad_rd + 1;
+ hrtimer_cancel(&pp->timer);
- dev_dbg(&pp->ntb->dev,
- "Ping bits %#llx read %#x write %#x\n",
- db_bits, spad_rd, spad_wr);
+ ret = pp_find_next_peer(pp);
+ if (ret == -ENODEV) {
+ dev_dbg(&pp->ntb->dev, "Got no peers, so cancel\n");
+ return;
+ }
- ntb_peer_spad_write(pp->ntb, PIDX, 0, spad_wr);
- ntb_peer_db_set(pp->ntb, db_bits);
- ntb_db_clear_mask(pp->ntb, db_mask);
+ dev_dbg(&pp->ntb->dev, "Ping-pong started with port %d, db %#llx\n",
+ ntb_peer_port_number(pp->ntb, pp->out_pidx), pp->out_db);
- pp->db_bits = 0;
- }
- spin_unlock_irqrestore(&pp->db_lock, irqflags);
+ hrtimer_start(&pp->timer, ms_to_ktime(delay_ms), HRTIMER_MODE_REL);
}
-static void pp_link_event(void *ctx)
+static void pp_clear(struct pp_ctx *pp)
{
- struct pp_ctx *pp = ctx;
+ hrtimer_cancel(&pp->timer);
- if (ntb_link_is_up(pp->ntb, NULL, NULL) == 1) {
- dev_dbg(&pp->ntb->dev, "link is up\n");
- pp_ping(&pp->db_timer);
- } else {
- dev_dbg(&pp->ntb->dev, "link is down\n");
- del_timer(&pp->db_timer);
- }
+ ntb_db_set_mask(pp->ntb, pp->in_db);
+
+ dev_dbg(&pp->ntb->dev, "Ping-pong cancelled\n");
}
-static void pp_db_event(void *ctx, int vec)
+static void pp_ping(struct pp_ctx *pp)
{
- struct pp_ctx *pp = ctx;
- u64 db_bits, db_mask;
- unsigned long irqflags;
+ u32 count;
- spin_lock_irqsave(&pp->db_lock, irqflags);
- {
- db_mask = ntb_db_vector_mask(pp->ntb, vec);
- db_bits = db_mask & ntb_db_read(pp->ntb);
- ntb_db_set_mask(pp->ntb, db_mask);
- ntb_db_clear(pp->ntb, db_bits);
+ count = atomic_read(&pp->count);
- pp->db_bits |= db_bits;
+ spin_lock(&pp->lock);
+ ntb_peer_spad_write(pp->ntb, pp->out_pidx, 0, count);
+ ntb_peer_msg_write(pp->ntb, pp->out_pidx, 0, count);
- mod_timer(&pp->db_timer, jiffies + pp->db_delay);
+ dev_dbg(&pp->ntb->dev, "Ping port %d spad %#x, msg %#x\n",
+ ntb_peer_port_number(pp->ntb, pp->out_pidx), count, count);
- dev_dbg(&pp->ntb->dev,
- "Pong vec %d bits %#llx\n",
- vec, db_bits);
- atomic_inc(&pp->count);
- }
- spin_unlock_irqrestore(&pp->db_lock, irqflags);
+ ntb_peer_db_set(pp->ntb, pp->out_db);
+ ntb_db_clear_mask(pp->ntb, pp->in_db);
+ spin_unlock(&pp->lock);
}
-static int pp_debugfs_setup(struct pp_ctx *pp)
+static void pp_pong(struct pp_ctx *pp)
{
- struct pci_dev *pdev = pp->ntb->pdev;
+ u32 msg_data = -1, spad_data = -1;
+ int pidx = 0;
- if (!pp_debugfs_dir)
- return -ENODEV;
+ /* Read pong data */
+ spad_data = ntb_spad_read(pp->ntb, 0);
+ msg_data = ntb_msg_read(pp->ntb, &pidx, 0);
+ ntb_msg_clear_sts(pp->ntb, -1);
- pp->debugfs_node_dir = debugfs_create_dir(pci_name(pdev),
- pp_debugfs_dir);
- if (!pp->debugfs_node_dir)
- return -ENODEV;
+ /*
+ * Scratchpad and message data may differ, since message register can't
+ * be rewritten unless status is cleared. Additionally either of them
+ * might be unsupported
+ */
+ dev_dbg(&pp->ntb->dev, "Pong spad %#x, msg %#x (port %d)\n",
+ spad_data, msg_data, ntb_peer_port_number(pp->ntb, pidx));
- pp->debugfs_count = debugfs_create_atomic_t("count", S_IRUSR | S_IWUSR,
- pp->debugfs_node_dir,
- &pp->count);
- if (!pp->debugfs_count)
- return -ENODEV;
+ atomic_inc(&pp->count);
- return 0;
+ ntb_db_set_mask(pp->ntb, pp->in_db);
+ ntb_db_clear(pp->ntb, pp->in_db);
+
+ hrtimer_start(&pp->timer, ms_to_ktime(delay_ms), HRTIMER_MODE_REL);
+}
+
+static enum hrtimer_restart pp_timer_func(struct hrtimer *t)
+{
+ struct pp_ctx *pp = to_pp_timer(t);
+
+ pp_ping(pp);
+
+ return HRTIMER_NORESTART;
+}
+
+static void pp_link_event(void *ctx)
+{
+ struct pp_ctx *pp = ctx;
+
+ pp_setup(pp);
+}
+
+static void pp_db_event(void *ctx, int vec)
+{
+ struct pp_ctx *pp = ctx;
+
+ pp_pong(pp);
}
static const struct ntb_ctx_ops pp_ops = {
.link_event = pp_link_event,
- .db_event = pp_db_event,
+ .db_event = pp_db_event
};
-static int pp_probe(struct ntb_client *client,
- struct ntb_dev *ntb)
+static int pp_check_ntb(struct ntb_dev *ntb)
{
- struct pp_ctx *pp;
- int rc;
+ u64 pmask;
if (ntb_db_is_unsafe(ntb)) {
- dev_dbg(&ntb->dev, "doorbell is unsafe\n");
- if (!unsafe) {
- rc = -EINVAL;
- goto err_pp;
- }
- }
-
- if (ntb_spad_count(ntb) < 1) {
- dev_dbg(&ntb->dev, "no enough scratchpads\n");
- rc = -EINVAL;
- goto err_pp;
+ dev_dbg(&ntb->dev, "Doorbell is unsafe\n");
+ if (!unsafe)
+ return -EINVAL;
}
if (ntb_spad_is_unsafe(ntb)) {
- dev_dbg(&ntb->dev, "scratchpad is unsafe\n");
- if (!unsafe) {
- rc = -EINVAL;
- goto err_pp;
- }
+ dev_dbg(&ntb->dev, "Scratchpad is unsafe\n");
+ if (!unsafe)
+ return -EINVAL;
}
- if (ntb_peer_port_count(ntb) != NTB_DEF_PEER_CNT)
- dev_warn(&ntb->dev, "multi-port NTB is unsupported\n");
+ pmask = GENMASK_ULL(ntb_peer_port_count(ntb), 0);
+ if ((ntb_db_valid_mask(ntb) & pmask) != pmask) {
+ dev_err(&ntb->dev, "Unsupported DB configuration\n");
+ return -EINVAL;
+ }
- pp = kmalloc(sizeof(*pp), GFP_KERNEL);
- if (!pp) {
- rc = -ENOMEM;
- goto err_pp;
+ if (ntb_spad_count(ntb) < 1 && ntb_msg_count(ntb) < 1) {
+ dev_err(&ntb->dev, "Scratchpads and messages unsupported\n");
+ return -EINVAL;
+ } else if (ntb_spad_count(ntb) < 1) {
+ dev_dbg(&ntb->dev, "Scratchpads unsupported\n");
+ } else if (ntb_msg_count(ntb) < 1) {
+ dev_dbg(&ntb->dev, "Messages unsupported\n");
}
+ return 0;
+}
+
+static struct pp_ctx *pp_create_data(struct ntb_dev *ntb)
+{
+ struct pp_ctx *pp;
+
+ pp = devm_kzalloc(&ntb->dev, sizeof(*pp), GFP_KERNEL);
+ if (!pp)
+ return ERR_PTR(-ENOMEM);
+
pp->ntb = ntb;
- pp->db_bits = 0;
atomic_set(&pp->count, 0);
- spin_lock_init(&pp->db_lock);
- timer_setup(&pp->db_timer, pp_ping, 0);
- pp->db_delay = msecs_to_jiffies(delay_ms);
+ spin_lock_init(&pp->lock);
+ hrtimer_init(&pp->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ pp->timer.function = pp_timer_func;
+
+ return pp;
+}
+
+static void pp_init_flds(struct pp_ctx *pp)
+{
+ int pidx, lport, pcnt;
+
+ /* Find global port index */
+ lport = ntb_port_number(pp->ntb);
+ pcnt = ntb_peer_port_count(pp->ntb);
+ for (pidx = 0; pidx < pcnt; pidx++) {
+ if (lport < ntb_peer_port_number(pp->ntb, pidx))
+ break;
+ }
- rc = ntb_set_ctx(ntb, pp, &pp_ops);
- if (rc)
- goto err_ctx;
+ pp->in_db = BIT_ULL(pidx);
+ pp->pmask = GENMASK_ULL(pidx, 0) >> 1;
+ pp->nmask = GENMASK_ULL(pcnt - 1, pidx);
- rc = pp_debugfs_setup(pp);
- if (rc)
- goto err_ctx;
+ dev_dbg(&pp->ntb->dev, "Inbound db %#llx, prev %#llx, next %#llx\n",
+ pp->in_db, pp->pmask, pp->nmask);
+}
+
+static int pp_mask_events(struct pp_ctx *pp)
+{
+ u64 db_mask, msg_mask;
+ int ret;
+
+ db_mask = ntb_db_valid_mask(pp->ntb);
+ ret = ntb_db_set_mask(pp->ntb, db_mask);
+ if (ret)
+ return ret;
- ntb_link_enable(ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
- ntb_link_event(ntb);
+ /* Skip message events masking if unsupported */
+ if (ntb_msg_count(pp->ntb) < 1)
+ return 0;
+
+ msg_mask = ntb_msg_outbits(pp->ntb) | ntb_msg_inbits(pp->ntb);
+ return ntb_msg_set_mask(pp->ntb, msg_mask);
+}
+
+static int pp_setup_ctx(struct pp_ctx *pp)
+{
+ int ret;
+
+ ret = ntb_set_ctx(pp->ntb, pp, &pp_ops);
+ if (ret)
+ return ret;
+
+ ntb_link_enable(pp->ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
+ /* Might be not necessary */
+ ntb_link_event(pp->ntb);
return 0;
+}
+
+static void pp_clear_ctx(struct pp_ctx *pp)
+{
+ ntb_link_disable(pp->ntb);
-err_ctx:
- kfree(pp);
-err_pp:
- return rc;
+ ntb_clear_ctx(pp->ntb);
}
-static void pp_remove(struct ntb_client *client,
- struct ntb_dev *ntb)
+static void pp_setup_dbgfs(struct pp_ctx *pp)
+{
+ struct pci_dev *pdev = pp->ntb->pdev;
+ void *ret;
+
+ pp->dbgfs_dir = debugfs_create_dir(pci_name(pdev), pp_dbgfs_topdir);
+
+ ret = debugfs_create_atomic_t("count", 0600, pp->dbgfs_dir, &pp->count);
+ if (!ret)
+ dev_warn(&pp->ntb->dev, "DebugFS unsupported\n");
+}
+
+static void pp_clear_dbgfs(struct pp_ctx *pp)
+{
+ debugfs_remove_recursive(pp->dbgfs_dir);
+}
+
+static int pp_probe(struct ntb_client *client, struct ntb_dev *ntb)
+{
+ struct pp_ctx *pp;
+ int ret;
+
+ ret = pp_check_ntb(ntb);
+ if (ret)
+ return ret;
+
+ pp = pp_create_data(ntb);
+ if (IS_ERR(pp))
+ return PTR_ERR(pp);
+
+ pp_init_flds(pp);
+
+ ret = pp_mask_events(pp);
+ if (ret)
+ return ret;
+
+ ret = pp_setup_ctx(pp);
+ if (ret)
+ return ret;
+
+ pp_setup_dbgfs(pp);
+
+ return 0;
+}
+
+static void pp_remove(struct ntb_client *client, struct ntb_dev *ntb)
{
struct pp_ctx *pp = ntb->ctx;
- debugfs_remove_recursive(pp->debugfs_node_dir);
+ pp_clear_dbgfs(pp);
- ntb_clear_ctx(ntb);
- del_timer_sync(&pp->db_timer);
- ntb_link_disable(ntb);
+ pp_clear_ctx(pp);
- kfree(pp);
+ pp_clear(pp);
}
static struct ntb_client pp_client = {
.ops = {
.probe = pp_probe,
- .remove = pp_remove,
- },
+ .remove = pp_remove
+ }
};
static int __init pp_init(void)
{
- int rc;
+ int ret;
if (debugfs_initialized())
- pp_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
+ pp_dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
- rc = ntb_register_client(&pp_client);
- if (rc)
- goto err_client;
+ ret = ntb_register_client(&pp_client);
+ if (ret)
+ debugfs_remove_recursive(pp_dbgfs_topdir);
- return 0;
-
-err_client:
- debugfs_remove_recursive(pp_debugfs_dir);
- return rc;
+ return ret;
}
module_init(pp_init);
static void __exit pp_exit(void)
{
ntb_unregister_client(&pp_client);
- debugfs_remove_recursive(pp_debugfs_dir);
+ debugfs_remove_recursive(pp_dbgfs_topdir);
}
module_exit(pp_exit);
+