From: Mikulas Patocka mpatocka@redhat.com
[ Upstream commit 6ca43ed8376a51afec790dd484a51804ade4352a ]
If we are in a place where it is known that interrupts are enabled, functions spin_lock_irq/spin_unlock_irq should be used instead of spin_lock_irqsave/spin_unlock_irqrestore.
spin_lock_irq and spin_unlock_irq are faster because they don't need to push and pop the flags register.
Signed-off-by: Mikulas Patocka mpatocka@redhat.com Signed-off-by: Nikos Tsironis ntsironis@arrikto.com Signed-off-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/dm-clone-metadata.c | 29 ++++++++++++----------------- drivers/md/dm-clone-metadata.h | 4 +++- drivers/md/dm-clone-target.c | 28 ++++++++++++---------------- 3 files changed, 27 insertions(+), 34 deletions(-)
diff --git a/drivers/md/dm-clone-metadata.c b/drivers/md/dm-clone-metadata.c index 2460cc6e0ef1d..581d11250333a 100644 --- a/drivers/md/dm-clone-metadata.c +++ b/drivers/md/dm-clone-metadata.c @@ -748,7 +748,7 @@ static int __metadata_commit(struct dm_clone_metadata *cmd) static int __flush_dmap(struct dm_clone_metadata *cmd, struct dirty_map *dmap) { int r; - unsigned long word, flags; + unsigned long word;
word = 0; do { @@ -772,9 +772,9 @@ static int __flush_dmap(struct dm_clone_metadata *cmd, struct dirty_map *dmap) return r;
/* Update the changed flag */ - spin_lock_irqsave(&cmd->bitmap_lock, flags); + spin_lock_irq(&cmd->bitmap_lock); dmap->changed = 0; - spin_unlock_irqrestore(&cmd->bitmap_lock, flags); + spin_unlock_irq(&cmd->bitmap_lock);
return 0; } @@ -782,7 +782,6 @@ static int __flush_dmap(struct dm_clone_metadata *cmd, struct dirty_map *dmap) int dm_clone_metadata_pre_commit(struct dm_clone_metadata *cmd) { int r = 0; - unsigned long flags; struct dirty_map *dmap, *next_dmap;
down_write(&cmd->lock); @@ -808,9 +807,9 @@ int dm_clone_metadata_pre_commit(struct dm_clone_metadata *cmd) }
/* Swap dirty bitmaps */ - spin_lock_irqsave(&cmd->bitmap_lock, flags); + spin_lock_irq(&cmd->bitmap_lock); cmd->current_dmap = next_dmap; - spin_unlock_irqrestore(&cmd->bitmap_lock, flags); + spin_unlock_irq(&cmd->bitmap_lock);
/* Set old dirty bitmap as currently committing */ cmd->committing_dmap = dmap; @@ -878,9 +877,9 @@ int dm_clone_cond_set_range(struct dm_clone_metadata *cmd, unsigned long start, { int r = 0; struct dirty_map *dmap; - unsigned long word, region_nr, flags; + unsigned long word, region_nr;
- spin_lock_irqsave(&cmd->bitmap_lock, flags); + spin_lock_irq(&cmd->bitmap_lock);
if (cmd->read_only) { r = -EPERM; @@ -898,7 +897,7 @@ int dm_clone_cond_set_range(struct dm_clone_metadata *cmd, unsigned long start, } } out: - spin_unlock_irqrestore(&cmd->bitmap_lock, flags); + spin_unlock_irq(&cmd->bitmap_lock);
return r; } @@ -965,13 +964,11 @@ int dm_clone_metadata_abort(struct dm_clone_metadata *cmd)
void dm_clone_metadata_set_read_only(struct dm_clone_metadata *cmd) { - unsigned long flags; - down_write(&cmd->lock);
- spin_lock_irqsave(&cmd->bitmap_lock, flags); + spin_lock_irq(&cmd->bitmap_lock); cmd->read_only = 1; - spin_unlock_irqrestore(&cmd->bitmap_lock, flags); + spin_unlock_irq(&cmd->bitmap_lock);
if (!cmd->fail_io) dm_bm_set_read_only(cmd->bm); @@ -981,13 +978,11 @@ void dm_clone_metadata_set_read_only(struct dm_clone_metadata *cmd)
void dm_clone_metadata_set_read_write(struct dm_clone_metadata *cmd) { - unsigned long flags; - down_write(&cmd->lock);
- spin_lock_irqsave(&cmd->bitmap_lock, flags); + spin_lock_irq(&cmd->bitmap_lock); cmd->read_only = 0; - spin_unlock_irqrestore(&cmd->bitmap_lock, flags); + spin_unlock_irq(&cmd->bitmap_lock);
if (!cmd->fail_io) dm_bm_set_read_write(cmd->bm); diff --git a/drivers/md/dm-clone-metadata.h b/drivers/md/dm-clone-metadata.h index 6a217f5ea98c0..d848b8799c07d 100644 --- a/drivers/md/dm-clone-metadata.h +++ b/drivers/md/dm-clone-metadata.h @@ -44,7 +44,9 @@ int dm_clone_set_region_hydrated(struct dm_clone_metadata *cmd, unsigned long re * @start: Starting region number * @nr_regions: Number of regions in the range * - * This function doesn't block, so it's safe to call it from interrupt context. + * This function doesn't block, but since it uses spin_lock_irq()/spin_unlock_irq() + * it's NOT safe to call it from any context where interrupts are disabled, e.g., + * from interrupt context. */ int dm_clone_cond_set_range(struct dm_clone_metadata *cmd, unsigned long start, unsigned long nr_regions); diff --git a/drivers/md/dm-clone-target.c b/drivers/md/dm-clone-target.c index 2addf611ef3d8..ad5dca5d20707 100644 --- a/drivers/md/dm-clone-target.c +++ b/drivers/md/dm-clone-target.c @@ -338,8 +338,6 @@ static void submit_bios(struct bio_list *bios) */ static void issue_bio(struct clone *clone, struct bio *bio) { - unsigned long flags; - if (!bio_triggers_commit(clone, bio)) { generic_make_request(bio); return; @@ -358,9 +356,9 @@ static void issue_bio(struct clone *clone, struct bio *bio) * Batch together any bios that trigger commits and then issue a single * commit for them in process_deferred_flush_bios(). */ - spin_lock_irqsave(&clone->lock, flags); + spin_lock_irq(&clone->lock); bio_list_add(&clone->deferred_flush_bios, bio); - spin_unlock_irqrestore(&clone->lock, flags); + spin_unlock_irq(&clone->lock);
wake_worker(clone); } @@ -475,7 +473,7 @@ static void complete_discard_bio(struct clone *clone, struct bio *bio, bool succ
static void process_discard_bio(struct clone *clone, struct bio *bio) { - unsigned long rs, re, flags; + unsigned long rs, re;
bio_region_range(clone, bio, &rs, &re); BUG_ON(re > clone->nr_regions); @@ -507,9 +505,9 @@ static void process_discard_bio(struct clone *clone, struct bio *bio) /* * Defer discard processing. */ - spin_lock_irqsave(&clone->lock, flags); + spin_lock_irq(&clone->lock); bio_list_add(&clone->deferred_discard_bios, bio); - spin_unlock_irqrestore(&clone->lock, flags); + spin_unlock_irq(&clone->lock);
wake_worker(clone); } @@ -1167,13 +1165,13 @@ static void process_deferred_discards(struct clone *clone) int r = -EPERM; struct bio *bio; struct blk_plug plug; - unsigned long rs, re, flags; + unsigned long rs, re; struct bio_list discards = BIO_EMPTY_LIST;
- spin_lock_irqsave(&clone->lock, flags); + spin_lock_irq(&clone->lock); bio_list_merge(&discards, &clone->deferred_discard_bios); bio_list_init(&clone->deferred_discard_bios); - spin_unlock_irqrestore(&clone->lock, flags); + spin_unlock_irq(&clone->lock);
if (bio_list_empty(&discards)) return; @@ -1203,13 +1201,12 @@ static void process_deferred_discards(struct clone *clone)
static void process_deferred_bios(struct clone *clone) { - unsigned long flags; struct bio_list bios = BIO_EMPTY_LIST;
- spin_lock_irqsave(&clone->lock, flags); + spin_lock_irq(&clone->lock); bio_list_merge(&bios, &clone->deferred_bios); bio_list_init(&clone->deferred_bios); - spin_unlock_irqrestore(&clone->lock, flags); + spin_unlock_irq(&clone->lock);
if (bio_list_empty(&bios)) return; @@ -1220,7 +1217,6 @@ static void process_deferred_bios(struct clone *clone) static void process_deferred_flush_bios(struct clone *clone) { struct bio *bio; - unsigned long flags; bool dest_dev_flushed; struct bio_list bios = BIO_EMPTY_LIST; struct bio_list bio_completions = BIO_EMPTY_LIST; @@ -1229,13 +1225,13 @@ static void process_deferred_flush_bios(struct clone *clone) * If there are any deferred flush bios, we must commit the metadata * before issuing them or signaling their completion. */ - spin_lock_irqsave(&clone->lock, flags); + spin_lock_irq(&clone->lock); bio_list_merge(&bios, &clone->deferred_flush_bios); bio_list_init(&clone->deferred_flush_bios);
bio_list_merge(&bio_completions, &clone->deferred_flush_completions); bio_list_init(&clone->deferred_flush_completions); - spin_unlock_irqrestore(&clone->lock, flags); + spin_unlock_irq(&clone->lock);
if (bio_list_empty(&bios) && bio_list_empty(&bio_completions) && !(dm_clone_changed_this_transaction(clone->cmd) && need_commit_due_to_time(clone)))