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 <mpatocka@xxxxxxxxxx>
---
drivers/md/dm-thin.c | 113 ++++++++++++++++++++-------------------------------
1 file changed, 46 insertions(+), 67 deletions(-)
Index: linux-2.6/drivers/md/dm-thin.c
===================================================================
--- linux-2.6.orig/drivers/md/dm-thin.c 2019-10-11 18:57:08.000000000 +0200
+++ linux-2.6/drivers/md/dm-thin.c 2019-10-11 21:33:40.000000000 +0200
@@ -609,13 +609,12 @@ static void error_thin_bio_list(struct t
blk_status_t error)
{
struct bio_list bios;
- unsigned long flags;
bio_list_init(&bios);
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
__merge_bio_list(&bios, master);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
error_bio_list(&bios, error);
}
@@ -623,15 +622,14 @@ static void error_thin_bio_list(struct t
static void requeue_deferred_cells(struct thin_c *tc)
{
struct pool *pool = tc->pool;
- unsigned long flags;
struct list_head cells;
struct dm_bio_prison_cell *cell, *tmp;
INIT_LIST_HEAD(&cells);
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
list_splice_init(&tc->deferred_cells, &cells);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
list_for_each_entry_safe(cell, tmp, &cells, user_list)
cell_requeue(pool, cell);
@@ -640,14 +638,13 @@ static void requeue_deferred_cells(struc
static void requeue_io(struct thin_c *tc)
{
struct bio_list bios;
- unsigned long flags;
bio_list_init(&bios);
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
__merge_bio_list(&bios, &tc->deferred_bio_list);
__merge_bio_list(&bios, &tc->retry_on_resume_list);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
error_bio_list(&bios, BLK_STS_DM_REQUEUE);
requeue_deferred_cells(tc);
@@ -756,7 +753,6 @@ static void inc_all_io_entry(struct pool
static void issue(struct thin_c *tc, struct bio *bio)
{
struct pool *pool = tc->pool;
- unsigned long flags;
if (!bio_triggers_commit(tc, bio)) {
generic_make_request(bio);
@@ -777,9 +773,9 @@ static void issue(struct thin_c *tc, str
* Batch together any bios that trigger commits and then issue a
* single commit for them in process_deferred_bios().
*/
- spin_lock_irqsave(&pool->lock, flags);
+ spin_lock_irq(&pool->lock);
bio_list_add(&pool->deferred_flush_bios, bio);
- spin_unlock_irqrestore(&pool->lock, flags);
+ spin_unlock_irq(&pool->lock);
}
static void remap_to_origin_and_issue(struct thin_c *tc, struct bio *bio)
@@ -960,7 +956,6 @@ static void process_prepared_mapping_fai
static void complete_overwrite_bio(struct thin_c *tc, struct bio *bio)
{
struct pool *pool = tc->pool;
- unsigned long flags;
/*
* If the bio has the REQ_FUA flag set we must commit the metadata
@@ -985,9 +980,9 @@ static void complete_overwrite_bio(struc
* Batch together any bios that trigger commits and then issue a
* single commit for them in process_deferred_bios().
*/
- spin_lock_irqsave(&pool->lock, flags);
+ spin_lock_irq(&pool->lock);
bio_list_add(&pool->deferred_flush_completions, bio);
- spin_unlock_irqrestore(&pool->lock, flags);
+ spin_unlock_irq(&pool->lock);
}
static void process_prepared_mapping(struct dm_thin_new_mapping *m)
@@ -1226,14 +1221,13 @@ static void process_prepared_discard_pas
static void process_prepared(struct pool *pool, struct list_head *head,
process_mapping_fn *fn)
{
- unsigned long flags;
struct list_head maps;
struct dm_thin_new_mapping *m, *tmp;
INIT_LIST_HEAD(&maps);
- spin_lock_irqsave(&pool->lock, flags);
+ spin_lock_irq(&pool->lock);
list_splice_init(head, &maps);
- spin_unlock_irqrestore(&pool->lock, flags);
+ spin_unlock_irq(&pool->lock);
list_for_each_entry_safe(m, tmp, &maps, list)
(*fn)(m);
@@ -1510,14 +1504,12 @@ static int commit(struct pool *pool)
static void check_low_water_mark(struct pool *pool, dm_block_t free_blocks)
{
- unsigned long flags;
-
if (free_blocks <= pool->low_water_blocks && !pool->low_water_triggered) {
DMWARN("%s: reached low water mark for data device: sending event.",
dm_device_name(pool->pool_md));
- spin_lock_irqsave(&pool->lock, flags);
+ spin_lock_irq(&pool->lock);
pool->low_water_triggered = true;
- spin_unlock_irqrestore(&pool->lock, flags);
+ spin_unlock_irq(&pool->lock);
dm_table_event(pool->ti->table);
}
}
@@ -1593,11 +1585,10 @@ static void retry_on_resume(struct bio *
{
struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
struct thin_c *tc = h->tc;
- unsigned long flags;
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
bio_list_add(&tc->retry_on_resume_list, bio);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
}
static blk_status_t should_error_unserviceable_bio(struct pool *pool)
@@ -2170,7 +2161,6 @@ static void __sort_thin_deferred_bios(st
static void process_thin_deferred_bios(struct thin_c *tc)
{
struct pool *pool = tc->pool;
- unsigned long flags;
struct bio *bio;
struct bio_list bios;
struct blk_plug plug;
@@ -2184,10 +2174,10 @@ static void process_thin_deferred_bios(s
bio_list_init(&bios);
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
if (bio_list_empty(&tc->deferred_bio_list)) {
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
return;
}
@@ -2196,7 +2186,7 @@ static void process_thin_deferred_bios(s
bio_list_merge(&bios, &tc->deferred_bio_list);
bio_list_init(&tc->deferred_bio_list);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
blk_start_plug(&plug);
while ((bio = bio_list_pop(&bios))) {
@@ -2206,10 +2196,10 @@ static void process_thin_deferred_bios(s
* prepared mappings to process.
*/
if (ensure_next_mapping(pool)) {
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
bio_list_add(&tc->deferred_bio_list, bio);
bio_list_merge(&tc->deferred_bio_list, &bios);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
break;
}
@@ -2264,16 +2254,15 @@ static unsigned sort_cells(struct pool *
static void process_thin_deferred_cells(struct thin_c *tc)
{
struct pool *pool = tc->pool;
- unsigned long flags;
struct list_head cells;
struct dm_bio_prison_cell *cell;
unsigned i, j, count;
INIT_LIST_HEAD(&cells);
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
list_splice_init(&tc->deferred_cells, &cells);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
if (list_empty(&cells))
return;
@@ -2294,9 +2283,9 @@ static void process_thin_deferred_cells(
for (j = i; j < count; j++)
list_add(&pool->cell_sort_array[j]->user_list, &cells);
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
list_splice(&cells, &tc->deferred_cells);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
return;
}
@@ -2349,7 +2338,6 @@ static struct thin_c *get_next_thin(stru
static void process_deferred_bios(struct pool *pool)
{
- unsigned long flags;
struct bio *bio;
struct bio_list bios, bio_completions;
struct thin_c *tc;
@@ -2368,13 +2356,13 @@ static void process_deferred_bios(struct
bio_list_init(&bios);
bio_list_init(&bio_completions);
- spin_lock_irqsave(&pool->lock, flags);
+ spin_lock_irq(&pool->lock);
bio_list_merge(&bios, &pool->deferred_flush_bios);
bio_list_init(&pool->deferred_flush_bios);
bio_list_merge(&bio_completions, &pool->deferred_flush_completions);
bio_list_init(&pool->deferred_flush_completions);
- spin_unlock_irqrestore(&pool->lock, flags);
+ spin_unlock_irq(&pool->lock);
if (bio_list_empty(&bios) && bio_list_empty(&bio_completions) &&
!(dm_pool_changed_this_transaction(pool->pmd) && need_commit_due_to_time(pool)))
@@ -2657,12 +2645,11 @@ static void metadata_operation_failed(st
*/
static void thin_defer_bio(struct thin_c *tc, struct bio *bio)
{
- unsigned long flags;
struct pool *pool = tc->pool;
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
bio_list_add(&tc->deferred_bio_list, bio);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
wake_worker(pool);
}
@@ -2678,13 +2665,12 @@ static void thin_defer_bio_with_throttle
static void thin_defer_cell(struct thin_c *tc, struct dm_bio_prison_cell *cell)
{
- unsigned long flags;
struct pool *pool = tc->pool;
throttle_lock(&pool->throttle);
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
list_add_tail(&cell->user_list, &tc->deferred_cells);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
throttle_unlock(&pool->throttle);
wake_worker(pool);
@@ -2810,15 +2796,14 @@ static int pool_is_congested(struct dm_t
static void requeue_bios(struct pool *pool)
{
- unsigned long flags;
struct thin_c *tc;
rcu_read_lock();
list_for_each_entry_rcu(tc, &pool->active_thins, list) {
- spin_lock_irqsave(&tc->lock, flags);
+ spin_lock_irq(&tc->lock);
bio_list_merge(&tc->deferred_bio_list, &tc->retry_on_resume_list);
bio_list_init(&tc->retry_on_resume_list);
- spin_unlock_irqrestore(&tc->lock, flags);
+ spin_unlock_irq(&tc->lock);
}
rcu_read_unlock();
}
@@ -3412,15 +3397,14 @@ static int pool_map(struct dm_target *ti
int r;
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
- unsigned long flags;
/*
* As this is a singleton target, ti->begin is always zero.
*/
- spin_lock_irqsave(&pool->lock, flags);
+ spin_lock_irq(&pool->lock);
bio_set_dev(bio, pt->data_dev->bdev);
r = DM_MAPIO_REMAPPED;
- spin_unlock_irqrestore(&pool->lock, flags);
+ spin_unlock_irq(&pool->lock);
return r;
}
@@ -3591,7 +3575,6 @@ static void pool_resume(struct dm_target
{
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
- unsigned long flags;
/*
* Must requeue active_thins' bios and then resume
@@ -3600,10 +3583,10 @@ static void pool_resume(struct dm_target
requeue_bios(pool);
pool_resume_active_thins(pool);
- spin_lock_irqsave(&pool->lock, flags);
+ spin_lock_irq(&pool->lock);
pool->low_water_triggered = false;
pool->suspended = false;
- spin_unlock_irqrestore(&pool->lock, flags);
+ spin_unlock_irq(&pool->lock);
do_waker(&pool->waker.work);
}
@@ -3612,11 +3595,10 @@ static void pool_presuspend(struct dm_ta
{
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
- unsigned long flags;
- spin_lock_irqsave(&pool->lock, flags);
+ spin_lock_irq(&pool->lock);
pool->suspended = true;
- spin_unlock_irqrestore(&pool->lock, flags);
+ spin_unlock_irq(&pool->lock);
pool_suspend_active_thins(pool);
}
@@ -3625,13 +3607,12 @@ static void pool_presuspend_undo(struct
{
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
- unsigned long flags;
pool_resume_active_thins(pool);
- spin_lock_irqsave(&pool->lock, flags);
+ spin_lock_irq(&pool->lock);
pool->suspended = false;
- spin_unlock_irqrestore(&pool->lock, flags);
+ spin_unlock_irq(&pool->lock);
}
static void pool_postsuspend(struct dm_target *ti)
@@ -4110,11 +4091,10 @@ static void thin_put(struct thin_c *tc)
static void thin_dtr(struct dm_target *ti)
{
struct thin_c *tc = ti->private;
- unsigned long flags;
- spin_lock_irqsave(&tc->pool->lock, flags);
+ spin_lock_irq(&tc->pool->lock);
list_del_rcu(&tc->list);
- spin_unlock_irqrestore(&tc->pool->lock, flags);
+ spin_unlock_irq(&tc->pool->lock);
synchronize_rcu();
thin_put(tc);
@@ -4150,7 +4130,6 @@ static int thin_ctr(struct dm_target *ti
struct thin_c *tc;
struct dm_dev *pool_dev, *origin_dev;
struct mapped_device *pool_md;
- unsigned long flags;
mutex_lock(&dm_thin_pool_table.mutex);
@@ -4244,9 +4223,9 @@ static int thin_ctr(struct dm_target *ti
mutex_unlock(&dm_thin_pool_table.mutex);
- spin_lock_irqsave(&tc->pool->lock, flags);
+ spin_lock_irq(&tc->pool->lock);
if (tc->pool->suspended) {
- spin_unlock_irqrestore(&tc->pool->lock, flags);
+ spin_unlock_irq(&tc->pool->lock);
mutex_lock(&dm_thin_pool_table.mutex); /* reacquire for __pool_dec */
ti->error = "Unable to activate thin device while pool is suspended";
r = -EINVAL;
@@ -4255,7 +4234,7 @@ static int thin_ctr(struct dm_target *ti
refcount_set(&tc->refcount, 1);
init_completion(&tc->can_destroy);
list_add_tail_rcu(&tc->list, &tc->pool->active_thins);
- spin_unlock_irqrestore(&tc->pool->lock, flags);
+ spin_unlock_irq(&tc->pool->lock);
/*
* This synchronize_rcu() call is needed here otherwise we risk a
* wake_worker() call finding no bios to process (because the newly
--
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