diff options
Diffstat (limited to 'drivers/md/dm-round-robin.c')
| -rw-r--r-- | drivers/md/dm-round-robin.c | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/drivers/md/dm-round-robin.c b/drivers/md/dm-round-robin.c index 65ffdc3..be9aa7f 100644 --- a/drivers/md/dm-round-robin.c +++ b/drivers/md/dm-round-robin.c @@ -46,6 +46,7 @@ static void free_paths(struct list_head *paths) struct selector { struct list_head valid_paths; struct list_head invalid_paths; + spinlock_t lock; }; static struct selector *alloc_selector(void) @@ -55,6 +56,7 @@ static struct selector *alloc_selector(void) if (s) { INIT_LIST_HEAD(&s->valid_paths); INIT_LIST_HEAD(&s->invalid_paths); + spin_lock_init(&s->lock); } return s; @@ -74,7 +76,7 @@ static int rr_create(struct path_selector *ps, unsigned argc, char **argv) static void rr_destroy(struct path_selector *ps) { - struct selector *s = (struct selector *) ps->context; + struct selector *s = ps->context; free_paths(&s->valid_paths); free_paths(&s->invalid_paths); @@ -111,10 +113,11 @@ static int rr_status(struct path_selector *ps, struct dm_path *path, static int rr_add_path(struct path_selector *ps, struct dm_path *path, int argc, char **argv, char **error) { - struct selector *s = (struct selector *) ps->context; + struct selector *s = ps->context; struct path_info *pi; unsigned repeat_count = RR_MIN_IO; char dummy; + unsigned long flags; if (argc > 1) { *error = "round-robin ps: incorrect number of arguments"; @@ -144,25 +147,33 @@ static int rr_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; } static void rr_fail_path(struct path_selector *ps, struct dm_path *p) { - struct selector *s = (struct selector *) ps->context; + unsigned long flags; + struct selector *s = ps->context; struct path_info *pi = p->pscontext; + spin_lock_irqsave(&s->lock, flags); list_move(&pi->list, &s->invalid_paths); + spin_unlock_irqrestore(&s->lock, flags); } static int rr_reinstate_path(struct path_selector *ps, struct dm_path *p) { - struct selector *s = (struct selector *) ps->context; + unsigned long flags; + struct selector *s = ps->context; struct path_info *pi = p->pscontext; + spin_lock_irqsave(&s->lock, flags); list_move(&pi->list, &s->valid_paths); + spin_unlock_irqrestore(&s->lock, flags); return 0; } @@ -170,14 +181,17 @@ static int rr_reinstate_path(struct path_selector *ps, struct dm_path *p) static struct dm_path *rr_select_path(struct path_selector *ps, unsigned *repeat_count, size_t nr_bytes) { - struct selector *s = (struct selector *) ps->context; + unsigned long flags; + struct selector *s = ps->context; struct path_info *pi = NULL; + spin_lock_irqsave(&s->lock, flags); if (!list_empty(&s->valid_paths)) { pi = list_entry(s->valid_paths.next, struct path_info, list); list_move_tail(&pi->list, &s->valid_paths); *repeat_count = pi->repeat_count; } + spin_unlock_irqrestore(&s->lock, flags); return pi ? pi->path : NULL; } |