diff options
author | Mikulas Patocka <mpatocka@redhat.com> | 2019-10-04 10:17:37 -0400 |
---|---|---|
committer | Mike Snitzer <snitzer@redhat.com> | 2019-11-05 14:35:42 -0500 |
commit | 6ca43ed8376a51afec790dd484a51804ade4352a (patch) | |
tree | 24740639a9d64462e0ab8ec29e6ed73231e818ab | |
parent | c1005322ff02110a4df7f0033368ea015062b583 (diff) | |
download | linux-stable-6ca43ed8376a51afec790dd484a51804ade4352a.tar.gz linux-stable-6ca43ed8376a51afec790dd484a51804ade4352a.tar.bz2 linux-stable-6ca43ed8376a51afec790dd484a51804ade4352a.zip |
dm clone: replace spin_lock_irqsave with spin_lock_irq
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>
-rw-r--r-- | drivers/md/dm-clone-metadata.c | 29 | ||||
-rw-r--r-- | drivers/md/dm-clone-metadata.h | 4 | ||||
-rw-r--r-- | 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 6bc8c1d1c351..08c552e5e41b 100644 --- a/drivers/md/dm-clone-metadata.c +++ b/drivers/md/dm-clone-metadata.c @@ -712,7 +712,7 @@ 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 { @@ -736,9 +736,9 @@ 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; } @@ -746,7 +746,6 @@ static int __flush_dmap(struct dm_clone_metadata *cmd, struct dirty_map *dmap) int dm_clone_metadata_commit(struct dm_clone_metadata *cmd) { int r = -EPERM; - unsigned long flags; struct dirty_map *dmap, *next_dmap; down_write(&cmd->lock); @@ -770,9 +769,9 @@ int dm_clone_metadata_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); /* * No one is accessing the old dirty bitmap anymore, so we can flush @@ -817,9 +816,9 @@ 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; @@ -836,7 +835,7 @@ 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; } @@ -903,13 +902,11 @@ out: 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); @@ -919,13 +916,11 @@ 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 434bff08508b..3fe50a781c11 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 4ca8f1977222..f7d1070a4d40 100644 --- a/drivers/md/dm-clone-target.c +++ b/drivers/md/dm-clone-target.c @@ -332,8 +332,6 @@ 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; @@ -352,9 +350,9 @@ 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); } @@ -469,7 +467,7 @@ 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); @@ -501,9 +499,9 @@ 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); } @@ -1140,13 +1138,13 @@ 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; @@ -1176,13 +1174,12 @@ out: 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; @@ -1193,7 +1190,6 @@ static void process_deferred_bios(struct clone *clone) static void process_deferred_flush_bios(struct clone *clone) { struct bio *bio; - unsigned long flags; struct bio_list bios = BIO_EMPTY_LIST; struct bio_list bio_completions = BIO_EMPTY_LIST; @@ -1201,13 +1197,13 @@ 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))) |