diff options
| -rw-r--r-- | drivers/md/dm-round-robin.c | 67 |
1 files changed, 14 insertions, 53 deletions
diff --git a/drivers/md/dm-round-robin.c b/drivers/md/dm-round-robin.c index 6c25213ab38c..bdbb7e6e8212 100644 --- a/drivers/md/dm-round-robin.c +++ b/drivers/md/dm-round-robin.c @@ -17,8 +17,8 @@ #include <linux/module.h> #define DM_MSG_PREFIX "multipath round-robin" -#define RR_MIN_IO 1000 -#define RR_VERSION "1.1.0" +#define RR_MIN_IO 1 +#define RR_VERSION "1.2.0" /*----------------------------------------------------------------- * Path-handling code, paths are held in lists @@ -47,44 +47,19 @@ struct selector { struct list_head valid_paths; struct list_head invalid_paths; spinlock_t lock; - struct dm_path * __percpu *current_path; - struct percpu_counter repeat_count; }; -static void set_percpu_current_path(struct selector *s, struct dm_path *path) -{ - int cpu; - - for_each_possible_cpu(cpu) - *per_cpu_ptr(s->current_path, cpu) = path; -} - static struct selector *alloc_selector(void) { struct selector *s = kmalloc(sizeof(*s), GFP_KERNEL); - if (!s) - return NULL; - - INIT_LIST_HEAD(&s->valid_paths); - INIT_LIST_HEAD(&s->invalid_paths); - spin_lock_init(&s->lock); - - s->current_path = alloc_percpu(struct dm_path *); - if (!s->current_path) - goto out_current_path; - set_percpu_current_path(s, NULL); - - if (percpu_counter_init(&s->repeat_count, 0, GFP_KERNEL)) - goto out_repeat_count; + if (s) { + INIT_LIST_HEAD(&s->valid_paths); + INIT_LIST_HEAD(&s->invalid_paths); + spin_lock_init(&s->lock); + } return s; - -out_repeat_count: - free_percpu(s->current_path); -out_current_path: - kfree(s); - return NULL;; } static int rr_create(struct path_selector *ps, unsigned argc, char **argv) @@ -105,8 +80,6 @@ static void rr_destroy(struct path_selector *ps) free_paths(&s->valid_paths); free_paths(&s->invalid_paths); - free_percpu(s->current_path); - percpu_counter_destroy(&s->repeat_count); kfree(s); ps->context = NULL; } @@ -157,6 +130,11 @@ static int rr_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; + } + /* allocate the path */ pi = kmalloc(sizeof(*pi), GFP_KERNEL); if (!pi) { @@ -183,9 +161,6 @@ static void rr_fail_path(struct path_selector *ps, struct dm_path *p) struct path_info *pi = p->pscontext; spin_lock_irqsave(&s->lock, flags); - if (p == *this_cpu_ptr(s->current_path)) - set_percpu_current_path(s, NULL); - list_move(&pi->list, &s->invalid_paths); spin_unlock_irqrestore(&s->lock, flags); } @@ -208,29 +183,15 @@ static struct dm_path *rr_select_path(struct path_selector *ps, size_t nr_bytes) unsigned long flags; struct selector *s = ps->context; struct path_info *pi = NULL; - struct dm_path *current_path = NULL; - - local_irq_save(flags); - current_path = *this_cpu_ptr(s->current_path); - if (current_path) { - percpu_counter_dec(&s->repeat_count); - if (percpu_counter_read_positive(&s->repeat_count) > 0) { - local_irq_restore(flags); - return current_path; - } - } - spin_lock(&s->lock); + 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); - percpu_counter_set(&s->repeat_count, pi->repeat_count); - set_percpu_current_path(s, pi->path); - current_path = pi->path; } spin_unlock_irqrestore(&s->lock, flags); - return current_path; + return pi ? pi->path : NULL; } static struct path_selector_type rr_ps = { |