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 the don't need to push and pop the flags register. Signed-off-by: Mikulas Patocka <[email protected]> --- drivers/md/dm-clone-metadata.c | 29 ++++++++++++----------------- drivers/md/dm-clone-target.c | 28 ++++++++++++---------------- 2 files changed, 24 insertions(+), 33 deletions(-) Index: linux-2.6/drivers/md/dm-clone-metadata.c =================================================================== --- linux-2.6.orig/drivers/md/dm-clone-metadata.c 2019-10-04 14:49:46.000000000 +0200 +++ linux-2.6/drivers/md/dm-clone-metadata.c 2019-10-04 16:07:49.000000000 +0200 @@ -712,7 +712,7 @@ static int __metadata_commit(struct dm_c 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_ 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_ 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_c } /* 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_cl { 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_cl } } 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(str 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); Index: linux-2.6/drivers/md/dm-clone-target.c =================================================================== --- linux-2.6.orig/drivers/md/dm-clone-target.c 2019-10-04 14:49:46.000000000 +0200 +++ linux-2.6/drivers/md/dm-clone-target.c 2019-10-04 16:03:39.000000000 +0200 @@ -332,8 +332,6 @@ static void submit_bios(struct bio_list */ 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 *clon * 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 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 c /* * 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(st 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 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( * 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))) -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
