From c6273411d1803ed03d4f0628bc629a8c45774351 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Mon, 27 Mar 2023 14:09:45 -0400 Subject: dm bio prison v1: prepare to intelligently size dm_bio_prison's prison_regions Add num_locks member to dm_bio_prison struct and use it rather than the NR_LOCKS magic value (64). Next commit will size the dm_bio_prison's prison_regions according to dm_num_hash_locks(). Signed-off-by: Mike Snitzer --- drivers/md/dm-bio-prison-v1.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) (limited to 'drivers/md/dm-bio-prison-v1.c') diff --git a/drivers/md/dm-bio-prison-v1.c b/drivers/md/dm-bio-prison-v1.c index 78bb559b521c..a7930ad1878b 100644 --- a/drivers/md/dm-bio-prison-v1.c +++ b/drivers/md/dm-bio-prison-v1.c @@ -17,7 +17,6 @@ /*----------------------------------------------------------------*/ #define NR_LOCKS 64 -#define LOCK_MASK (NR_LOCKS - 1) #define MIN_CELLS 1024 struct prison_region { @@ -26,8 +25,9 @@ struct prison_region { } ____cacheline_aligned_in_smp; struct dm_bio_prison { - struct prison_region regions[NR_LOCKS]; mempool_t cell_pool; + unsigned int num_locks; + struct prison_region regions[NR_LOCKS]; }; static struct kmem_cache *_cell_cache; @@ -46,8 +46,9 @@ struct dm_bio_prison *dm_bio_prison_create(void) if (!prison) return NULL; + prison->num_locks = NR_LOCKS; - for (i = 0; i < NR_LOCKS; i++) { + for (i = 0; i < prison->num_locks; i++) { spin_lock_init(&prison->regions[i].lock); prison->regions[i].cell = RB_ROOT; } @@ -115,9 +116,9 @@ static int cmp_keys(struct dm_cell_key *lhs, return 0; } -static unsigned lock_nr(struct dm_cell_key *key) +static unsigned lock_nr(struct dm_cell_key *key, unsigned int num_locks) { - return (key->block_begin >> BIO_PRISON_MAX_RANGE_SHIFT) & LOCK_MASK; + return (key->block_begin >> BIO_PRISON_MAX_RANGE_SHIFT) & (num_locks - 1); } bool dm_cell_key_has_valid_range(struct dm_cell_key *key) @@ -176,7 +177,7 @@ static int bio_detain(struct dm_bio_prison *prison, struct dm_bio_prison_cell **cell_result) { int r; - unsigned l = lock_nr(key); + unsigned l = lock_nr(key, prison->num_locks); spin_lock_irq(&prison->regions[l].lock); r = __bio_detain(&prison->regions[l].cell, key, inmate, cell_prealloc, cell_result); @@ -224,7 +225,7 @@ void dm_cell_release(struct dm_bio_prison *prison, struct dm_bio_prison_cell *cell, struct bio_list *bios) { - unsigned l = lock_nr(&cell->key); + unsigned l = lock_nr(&cell->key, prison->num_locks); spin_lock_irq(&prison->regions[l].lock); __cell_release(&prison->regions[l].cell, cell, bios); @@ -247,7 +248,7 @@ void dm_cell_release_no_holder(struct dm_bio_prison *prison, struct dm_bio_prison_cell *cell, struct bio_list *inmates) { - unsigned l = lock_nr(&cell->key); + unsigned l = lock_nr(&cell->key, prison->num_locks); unsigned long flags; spin_lock_irqsave(&prison->regions[l].lock, flags); @@ -277,7 +278,7 @@ void dm_cell_visit_release(struct dm_bio_prison *prison, void *context, struct dm_bio_prison_cell *cell) { - unsigned l = lock_nr(&cell->key); + unsigned l = lock_nr(&cell->key, prison->num_locks); spin_lock_irq(&prison->regions[l].lock); visit_fn(context, cell); rb_erase(&cell->node, &prison->regions[l].cell); @@ -301,7 +302,7 @@ int dm_cell_promote_or_release(struct dm_bio_prison *prison, struct dm_bio_prison_cell *cell) { int r; - unsigned l = lock_nr(&cell->key); + unsigned l = lock_nr(&cell->key, prison->num_locks); spin_lock_irq(&prison->regions[l].lock); r = __promote_or_release(&prison->regions[l].cell, cell); -- cgit v1.2.3