From fba10109a45d864bab98ae90dd63bcc2789352b3 Mon Sep 17 00:00:00 2001 From: Joe Thornber Date: Fri, 29 May 2015 10:20:56 +0100 Subject: dm cache: age and write back cache entries even without active IO The policy tick() method is normally called from interrupt context. Both the mq and smq policies do some bottom half work for the tick method in their map functions. However if no IO is going through the cache, then that bottom half work doesn't occur. With these policies this means recently hit entries do not age and do not get written back as early as we'd like. Fix this by introducing a new 'can_block' parameter to the tick() method. When this is set the bottom half work occurs immediately. 'can_block' is set when the tick method is called every second by the core target (not in interrupt context). Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer --- drivers/md/dm-cache-policy-internal.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/md/dm-cache-policy-internal.h') diff --git a/drivers/md/dm-cache-policy-internal.h b/drivers/md/dm-cache-policy-internal.h index ccbe852d5362..2816018faa7f 100644 --- a/drivers/md/dm-cache-policy-internal.h +++ b/drivers/md/dm-cache-policy-internal.h @@ -83,10 +83,10 @@ static inline dm_cblock_t policy_residency(struct dm_cache_policy *p) return p->residency(p); } -static inline void policy_tick(struct dm_cache_policy *p) +static inline void policy_tick(struct dm_cache_policy *p, bool can_block) { if (p->tick) - return p->tick(p); + return p->tick(p, can_block); } static inline int policy_emit_config_values(struct dm_cache_policy *p, char *result, -- cgit v1.2.3