diff options
Diffstat (limited to 'drivers/md/dm-service-time.c')
| -rw-r--r-- | drivers/md/dm-service-time.c | 35 |
1 files changed, 27 insertions, 8 deletions
diff --git a/drivers/md/dm-service-time.c b/drivers/md/dm-service-time.c index 9df8f6bd6418..7b8642045c55 100644 --- a/drivers/md/dm-service-time.c +++ b/drivers/md/dm-service-time.c @@ -19,11 +19,12 @@ #define ST_MAX_RELATIVE_THROUGHPUT 100 #define ST_MAX_RELATIVE_THROUGHPUT_SHIFT 7 #define ST_MAX_INFLIGHT_SIZE ((size_t)-1 >> ST_MAX_RELATIVE_THROUGHPUT_SHIFT) -#define ST_VERSION "0.2.0" +#define ST_VERSION "0.3.0" struct selector { struct list_head valid_paths; struct list_head failed_paths; + spinlock_t lock; }; struct path_info { @@ -41,6 +42,7 @@ static struct selector *alloc_selector(void) if (s) { INIT_LIST_HEAD(&s->valid_paths); INIT_LIST_HEAD(&s->failed_paths); + spin_lock_init(&s->lock); } return s; @@ -111,6 +113,7 @@ static int st_add_path(struct path_selector *ps, struct dm_path *path, unsigned repeat_count = ST_MIN_IO; unsigned relative_throughput = 1; char dummy; + unsigned long flags; /* * Arguments: [<repeat_count> [<relative_throughput>]] @@ -134,6 +137,11 @@ static int st_add_path(struct path_selector *ps, struct dm_path *path, return -EINVAL; } + if (repeat_count > 1) { + DMWARN_LIMIT("repeat_count > 1 is deprecated, using 1 instead"); + repeat_count = 1; + } + if ((argc == 2) && (sscanf(argv[1], "%u%c", &relative_throughput, &dummy) != 1 || relative_throughput > ST_MAX_RELATIVE_THROUGHPUT)) { @@ -155,7 +163,9 @@ static int st_add_path(struct path_selector *ps, struct dm_path *path, path->pscontext = pi; + spin_lock_irqsave(&s->lock, flags); list_add_tail(&pi->list, &s->valid_paths); + spin_unlock_irqrestore(&s->lock, flags); return 0; } @@ -164,16 +174,22 @@ static void st_fail_path(struct path_selector *ps, struct dm_path *path) { struct selector *s = ps->context; struct path_info *pi = path->pscontext; + unsigned long flags; + spin_lock_irqsave(&s->lock, flags); list_move(&pi->list, &s->failed_paths); + spin_unlock_irqrestore(&s->lock, flags); } static int st_reinstate_path(struct path_selector *ps, struct dm_path *path) { struct selector *s = ps->context; struct path_info *pi = path->pscontext; + unsigned long flags; + spin_lock_irqsave(&s->lock, flags); list_move_tail(&pi->list, &s->valid_paths); + spin_unlock_irqrestore(&s->lock, flags); return 0; } @@ -255,14 +271,16 @@ static int st_compare_load(struct path_info *pi1, struct path_info *pi2, return pi2->relative_throughput - pi1->relative_throughput; } -static struct dm_path *st_select_path(struct path_selector *ps, - unsigned *repeat_count, size_t nr_bytes) +static struct dm_path *st_select_path(struct path_selector *ps, size_t nr_bytes) { struct selector *s = ps->context; struct path_info *pi = NULL, *best = NULL; + struct dm_path *ret = NULL; + unsigned long flags; + spin_lock_irqsave(&s->lock, flags); if (list_empty(&s->valid_paths)) - return NULL; + goto out; /* Change preferred (first in list) path to evenly balance. */ list_move_tail(s->valid_paths.next, &s->valid_paths); @@ -272,11 +290,12 @@ static struct dm_path *st_select_path(struct path_selector *ps, best = pi; if (!best) - return NULL; - - *repeat_count = best->repeat_count; + goto out; - return best->path; + ret = best->path; +out: + spin_unlock_irqrestore(&s->lock, flags); + return ret; } static int st_start_io(struct path_selector *ps, struct dm_path *path, |