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path: root/drivers/md/dm-mpath.c
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Diffstat (limited to 'drivers/md/dm-mpath.c')
-rw-r--r--drivers/md/dm-mpath.c67
1 files changed, 42 insertions, 25 deletions
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 487ecda90ad4..b82d28819e2a 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -23,6 +23,8 @@
#define DM_MSG_PREFIX "multipath"
#define MESG_STR(x) x, sizeof(x)
+#define DM_PG_INIT_DELAY_MSECS 2000
+#define DM_PG_INIT_DELAY_DEFAULT ((unsigned) -1)
/* Path properties */
struct pgpath {
@@ -33,8 +35,7 @@ struct pgpath {
unsigned fail_count; /* Cumulative failure count */
struct dm_path path;
- struct work_struct deactivate_path;
- struct work_struct activate_path;
+ struct delayed_work activate_path;
};
#define path_to_pgpath(__pgp) container_of((__pgp), struct pgpath, path)
@@ -65,11 +66,15 @@ struct multipath {
const char *hw_handler_name;
char *hw_handler_params;
+
unsigned nr_priority_groups;
struct list_head priority_groups;
+
+ wait_queue_head_t pg_init_wait; /* Wait for pg_init completion */
+
unsigned pg_init_required; /* pg_init needs calling? */
unsigned pg_init_in_progress; /* Only one pg_init allowed at once */
- wait_queue_head_t pg_init_wait; /* Wait for pg_init completion */
+ unsigned pg_init_delay_retry; /* Delay pg_init retry? */
unsigned nr_valid_paths; /* Total number of usable paths */
struct pgpath *current_pgpath;
@@ -82,6 +87,7 @@ struct multipath {
unsigned saved_queue_if_no_path;/* Saved state during suspension */
unsigned pg_init_retries; /* Number of times to retry pg_init */
unsigned pg_init_count; /* Number of times pg_init called */
+ unsigned pg_init_delay_msecs; /* Number of msecs before pg_init retry */
struct work_struct process_queued_ios;
struct list_head queued_ios;
@@ -116,7 +122,6 @@ static struct workqueue_struct *kmultipathd, *kmpath_handlerd;
static void process_queued_ios(struct work_struct *work);
static void trigger_event(struct work_struct *work);
static void activate_path(struct work_struct *work);
-static void deactivate_path(struct work_struct *work);
/*-----------------------------------------------
@@ -129,8 +134,7 @@ static struct pgpath *alloc_pgpath(void)
if (pgpath) {
pgpath->is_active = 1;
- INIT_WORK(&pgpath->deactivate_path, deactivate_path);
- INIT_WORK(&pgpath->activate_path, activate_path);
+ INIT_DELAYED_WORK(&pgpath->activate_path, activate_path);
}
return pgpath;
@@ -141,14 +145,6 @@ static void free_pgpath(struct pgpath *pgpath)
kfree(pgpath);
}
-static void deactivate_path(struct work_struct *work)
-{
- struct pgpath *pgpath =
- container_of(work, struct pgpath, deactivate_path);
-
- blk_abort_queue(pgpath->path.dev->bdev->bd_disk->queue);
-}
-
static struct priority_group *alloc_priority_group(void)
{
struct priority_group *pg;
@@ -199,6 +195,7 @@ static struct multipath *alloc_multipath(struct dm_target *ti)
INIT_LIST_HEAD(&m->queued_ios);
spin_lock_init(&m->lock);
m->queue_io = 1;
+ m->pg_init_delay_msecs = DM_PG_INIT_DELAY_DEFAULT;
INIT_WORK(&m->process_queued_ios, process_queued_ios);
INIT_WORK(&m->trigger_event, trigger_event);
init_waitqueue_head(&m->pg_init_wait);
@@ -238,14 +235,19 @@ static void free_multipath(struct multipath *m)
static void __pg_init_all_paths(struct multipath *m)
{
struct pgpath *pgpath;
+ unsigned long pg_init_delay = 0;
m->pg_init_count++;
m->pg_init_required = 0;
+ if (m->pg_init_delay_retry)
+ pg_init_delay = msecs_to_jiffies(m->pg_init_delay_msecs != DM_PG_INIT_DELAY_DEFAULT ?
+ m->pg_init_delay_msecs : DM_PG_INIT_DELAY_MSECS);
list_for_each_entry(pgpath, &m->current_pg->pgpaths, list) {
/* Skip failed paths */
if (!pgpath->is_active)
continue;
- if (queue_work(kmpath_handlerd, &pgpath->activate_path))
+ if (queue_delayed_work(kmpath_handlerd, &pgpath->activate_path,
+ pg_init_delay))
m->pg_init_in_progress++;
}
}
@@ -793,8 +795,9 @@ static int parse_features(struct arg_set *as, struct multipath *m)
const char *param_name;
static struct param _params[] = {
- {0, 3, "invalid number of feature args"},
+ {0, 5, "invalid number of feature args"},
{1, 50, "pg_init_retries must be between 1 and 50"},
+ {0, 60000, "pg_init_delay_msecs must be between 0 and 60000"},
};
r = read_param(_params, shift(as), &argc, &ti->error);
@@ -821,6 +824,14 @@ static int parse_features(struct arg_set *as, struct multipath *m)
continue;
}
+ if (!strnicmp(param_name, MESG_STR("pg_init_delay_msecs")) &&
+ (argc >= 1)) {
+ r = read_param(_params + 2, shift(as),
+ &m->pg_init_delay_msecs, &ti->error);
+ argc--;
+ continue;
+ }
+
ti->error = "Unrecognised multipath feature request";
r = -EINVAL;
} while (argc && !r);
@@ -931,7 +942,7 @@ static void flush_multipath_work(struct multipath *m)
flush_workqueue(kmpath_handlerd);
multipath_wait_for_pg_init_completion(m);
flush_workqueue(kmultipathd);
- flush_scheduled_work();
+ flush_work_sync(&m->trigger_event);
}
static void multipath_dtr(struct dm_target *ti)
@@ -995,7 +1006,6 @@ static int fail_path(struct pgpath *pgpath)
pgpath->path.dev->name, m->nr_valid_paths);
schedule_work(&m->trigger_event);
- queue_work(kmultipathd, &pgpath->deactivate_path);
out:
spin_unlock_irqrestore(&m->lock, flags);
@@ -1034,7 +1044,7 @@ static int reinstate_path(struct pgpath *pgpath)
m->current_pgpath = NULL;
queue_work(kmultipathd, &m->process_queued_ios);
} else if (m->hw_handler_name && (m->current_pg == pgpath->pg)) {
- if (queue_work(kmpath_handlerd, &pgpath->activate_path))
+ if (queue_work(kmpath_handlerd, &pgpath->activate_path.work))
m->pg_init_in_progress++;
}
@@ -1169,6 +1179,7 @@ static void pg_init_done(void *data, int errors)
struct priority_group *pg = pgpath->pg;
struct multipath *m = pg->m;
unsigned long flags;
+ unsigned delay_retry = 0;
/* device or driver problems */
switch (errors) {
@@ -1193,8 +1204,9 @@ static void pg_init_done(void *data, int errors)
*/
bypass_pg(m, pg, 1);
break;
- /* TODO: For SCSI_DH_RETRY we should wait a couple seconds */
case SCSI_DH_RETRY:
+ /* Wait before retrying. */
+ delay_retry = 1;
case SCSI_DH_IMM_RETRY:
case SCSI_DH_RES_TEMP_UNAVAIL:
if (pg_init_limit_reached(m, pgpath))
@@ -1227,6 +1239,7 @@ static void pg_init_done(void *data, int errors)
if (!m->pg_init_required)
m->queue_io = 0;
+ m->pg_init_delay_retry = delay_retry;
queue_work(kmultipathd, &m->process_queued_ios);
/*
@@ -1241,7 +1254,7 @@ out:
static void activate_path(struct work_struct *work)
{
struct pgpath *pgpath =
- container_of(work, struct pgpath, activate_path);
+ container_of(work, struct pgpath, activate_path.work);
scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev),
pg_init_done, pgpath);
@@ -1382,11 +1395,14 @@ static int multipath_status(struct dm_target *ti, status_type_t type,
DMEMIT("2 %u %u ", m->queue_size, m->pg_init_count);
else {
DMEMIT("%u ", m->queue_if_no_path +
- (m->pg_init_retries > 0) * 2);
+ (m->pg_init_retries > 0) * 2 +
+ (m->pg_init_delay_msecs != DM_PG_INIT_DELAY_DEFAULT) * 2);
if (m->queue_if_no_path)
DMEMIT("queue_if_no_path ");
if (m->pg_init_retries)
DMEMIT("pg_init_retries %u ", m->pg_init_retries);
+ if (m->pg_init_delay_msecs != DM_PG_INIT_DELAY_DEFAULT)
+ DMEMIT("pg_init_delay_msecs %u ", m->pg_init_delay_msecs);
}
if (!m->hw_handler_name || type == STATUSTYPE_INFO)
@@ -1655,7 +1671,7 @@ out:
*---------------------------------------------------------------*/
static struct target_type multipath_target = {
.name = "multipath",
- .version = {1, 1, 1},
+ .version = {1, 2, 0},
.module = THIS_MODULE,
.ctr = multipath_ctr,
.dtr = multipath_dtr,
@@ -1687,7 +1703,7 @@ static int __init dm_multipath_init(void)
return -EINVAL;
}
- kmultipathd = create_workqueue("kmpathd");
+ kmultipathd = alloc_workqueue("kmpathd", WQ_MEM_RECLAIM, 0);
if (!kmultipathd) {
DMERR("failed to create workqueue kmpathd");
dm_unregister_target(&multipath_target);
@@ -1701,7 +1717,8 @@ static int __init dm_multipath_init(void)
* old workqueue would also create a bottleneck in the
* path of the storage hardware device activation.
*/
- kmpath_handlerd = create_singlethread_workqueue("kmpath_handlerd");
+ kmpath_handlerd = alloc_ordered_workqueue("kmpath_handlerd",
+ WQ_MEM_RECLAIM);
if (!kmpath_handlerd) {
DMERR("failed to create workqueue kmpath_handlerd");
destroy_workqueue(kmultipathd);