dm clone: replace spin_lock_irqsave with spin_lock_irq

[ 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>

diff --git a/drivers/md/dm-clone-metadata.c b/drivers/md/dm-clone-metadata.c
index 2460cc6e0ef1df700d3e5b0e12abe51e8c41e351..581d11250333a1e2f1bfae84d71531dea28eb9a2 100644 (file)
--- 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;
 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 {
 
        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 */
                return r;
 
        /* Update the changed flag */

-       spin_lock_irqsave(&cmd->bitmap_lock, flags);
+       spin_lock_irq(&cmd->bitmap_lock);

        dmap->changed = 0;
        dmap->changed = 0;

-       spin_unlock_irqrestore(&cmd->bitmap_lock, flags);
+       spin_unlock_irq(&cmd->bitmap_lock);

 
        return 0;
 }
 
        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;
 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);
        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 */
        }
 
        /* Swap dirty bitmaps */

-       spin_lock_irqsave(&cmd->bitmap_lock, flags);
+       spin_lock_irq(&cmd->bitmap_lock);

        cmd->current_dmap = next_dmap;
        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;
 
        /* 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;
 {
        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;
 
        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:
                }
        }
 out:

-       spin_unlock_irqrestore(&cmd->bitmap_lock, flags);
+       spin_unlock_irq(&cmd->bitmap_lock);

 
        return r;
 }
 
        return r;
 }


@@ -965,13 +964,11 @@ out:
 
 void dm_clone_metadata_set_read_only(struct dm_clone_metadata *cmd)
 {
 
 void dm_clone_metadata_set_read_only(struct dm_clone_metadata *cmd)
 {

-       unsigned long flags;
-

        down_write(&cmd->lock);
 
        down_write(&cmd->lock);
 

-       spin_lock_irqsave(&cmd->bitmap_lock, flags);
+       spin_lock_irq(&cmd->bitmap_lock);

        cmd->read_only = 1;
        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);
 
        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)
 {
 
 void dm_clone_metadata_set_read_write(struct dm_clone_metadata *cmd)
 {

-       unsigned long flags;
-

        down_write(&cmd->lock);
 
        down_write(&cmd->lock);
 

-       spin_lock_irqsave(&cmd->bitmap_lock, flags);
+       spin_lock_irq(&cmd->bitmap_lock);

        cmd->read_only = 0;
        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);
 
        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 6a217f5ea98c0bdefe386c90a54c889a9d761fcf..d848b8799c07dabc272014163aa3e6c571e37d5e 100644 (file)
--- 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
  *
  * @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);
  */
 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 2addf611ef3d8c492623fa362edbb0caaa71bd49..ad5dca5d20707b3a10843ac098dca88d20c4c8bd 100644 (file)
--- 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)
 {
  */
 static void issue_bio(struct clone *clone, struct bio *bio)
 {

-       unsigned long flags;
-

        if (!bio_triggers_commit(clone, bio)) {
                generic_make_request(bio);
                return;
        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().
         */
         * 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);
        bio_list_add(&clone->deferred_flush_bios, bio);

-       spin_unlock_irqrestore(&clone->lock, flags);
+       spin_unlock_irq(&clone->lock);

 
        wake_worker(clone);
 }
 
        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)
 {
 
 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);
 
        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.
         */
        /*
         * Defer discard processing.
         */

-       spin_lock_irqsave(&clone->lock, flags);
+       spin_lock_irq(&clone->lock);

        bio_list_add(&clone->deferred_discard_bios, bio);
        bio_list_add(&clone->deferred_discard_bios, bio);

-       spin_unlock_irqrestore(&clone->lock, flags);
+       spin_unlock_irq(&clone->lock);

 
        wake_worker(clone);
 }
 
        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;
        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;
 
        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);
        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;
 
        if (bio_list_empty(&discards))
                return;


@@ -1203,13 +1201,12 @@ out:
 
 static void process_deferred_bios(struct clone *clone)
 {
 
 static void process_deferred_bios(struct clone *clone)
 {

-       unsigned long flags;

        struct bio_list bios = BIO_EMPTY_LIST;
 
        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);
        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;
 
        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;
 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;
        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.
         */
         * 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);
        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)))
 
        if (bio_list_empty(&bios) && bio_list_empty(&bio_completions) &&
            !(dm_clone_changed_this_transaction(clone->cmd) && need_commit_due_to_time(clone)))