6.6-stable review patch. If anyone has any objections, please let me know.
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From: Mikulas Patocka mpatocka@redhat.com
commit 346dbf1b1345476a6524512892cceb931bee3039 upstream.
The commit 4c39529663b9 adds a warning about duplicate cache names if CONFIG_DEBUG_VM is selected. These warnings are triggered by the dm-cache code.
The dm-cache code allocates a slab cache for each device. This commit changes it to allocate just one slab cache in the module init function.
Signed-off-by: Mikulas Patocka mpatocka@redhat.com Fixes: 4c39529663b9 ("slab: Warn on duplicate cache names when DEBUG_VM=y") Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/md/dm-cache-background-tracker.c | 25 ++++++------------------- drivers/md/dm-cache-background-tracker.h | 8 ++++++++ drivers/md/dm-cache-target.c | 25 ++++++++++++++++++++----- 3 files changed, 34 insertions(+), 24 deletions(-)
--- a/drivers/md/dm-cache-background-tracker.c +++ b/drivers/md/dm-cache-background-tracker.c @@ -11,12 +11,6 @@
#define DM_MSG_PREFIX "dm-background-tracker"
-struct bt_work { - struct list_head list; - struct rb_node node; - struct policy_work work; -}; - struct background_tracker { unsigned int max_work; atomic_t pending_promotes; @@ -26,10 +20,10 @@ struct background_tracker { struct list_head issued; struct list_head queued; struct rb_root pending; - - struct kmem_cache *work_cache; };
+struct kmem_cache *btracker_work_cache = NULL; + struct background_tracker *btracker_create(unsigned int max_work) { struct background_tracker *b = kmalloc(sizeof(*b), GFP_KERNEL); @@ -48,12 +42,6 @@ struct background_tracker *btracker_crea INIT_LIST_HEAD(&b->queued);
b->pending = RB_ROOT; - b->work_cache = KMEM_CACHE(bt_work, 0); - if (!b->work_cache) { - DMERR("couldn't create mempool for background work items"); - kfree(b); - b = NULL; - }
return b; } @@ -66,10 +54,9 @@ void btracker_destroy(struct background_ BUG_ON(!list_empty(&b->issued)); list_for_each_entry_safe (w, tmp, &b->queued, list) { list_del(&w->list); - kmem_cache_free(b->work_cache, w); + kmem_cache_free(btracker_work_cache, w); }
- kmem_cache_destroy(b->work_cache); kfree(b); } EXPORT_SYMBOL_GPL(btracker_destroy); @@ -180,7 +167,7 @@ static struct bt_work *alloc_work(struct if (max_work_reached(b)) return NULL;
- return kmem_cache_alloc(b->work_cache, GFP_NOWAIT); + return kmem_cache_alloc(btracker_work_cache, GFP_NOWAIT); }
int btracker_queue(struct background_tracker *b, @@ -203,7 +190,7 @@ int btracker_queue(struct background_tra * There was a race, we'll just ignore this second * bit of work for the same oblock. */ - kmem_cache_free(b->work_cache, w); + kmem_cache_free(btracker_work_cache, w); return -EINVAL; }
@@ -244,7 +231,7 @@ void btracker_complete(struct background update_stats(b, &w->work, -1); rb_erase(&w->node, &b->pending); list_del(&w->list); - kmem_cache_free(b->work_cache, w); + kmem_cache_free(btracker_work_cache, w); } EXPORT_SYMBOL_GPL(btracker_complete);
--- a/drivers/md/dm-cache-background-tracker.h +++ b/drivers/md/dm-cache-background-tracker.h @@ -26,6 +26,14 @@ * protected with a spinlock. */
+struct bt_work { + struct list_head list; + struct rb_node node; + struct policy_work work; +}; + +extern struct kmem_cache *btracker_work_cache; + struct background_work; struct background_tracker;
--- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -10,6 +10,7 @@ #include "dm-bio-record.h" #include "dm-cache-metadata.h" #include "dm-io-tracker.h" +#include "dm-cache-background-tracker.h"
#include <linux/dm-io.h> #include <linux/dm-kcopyd.h> @@ -2267,7 +2268,7 @@ static int parse_cache_args(struct cache
/*----------------------------------------------------------------*/
-static struct kmem_cache *migration_cache; +static struct kmem_cache *migration_cache = NULL;
#define NOT_CORE_OPTION 1
@@ -3455,22 +3456,36 @@ static int __init dm_cache_init(void) int r;
migration_cache = KMEM_CACHE(dm_cache_migration, 0); - if (!migration_cache) - return -ENOMEM; + if (!migration_cache) { + r = -ENOMEM; + goto err; + } + + btracker_work_cache = kmem_cache_create("dm_cache_bt_work", + sizeof(struct bt_work), __alignof__(struct bt_work), 0, NULL); + if (!btracker_work_cache) { + r = -ENOMEM; + goto err; + }
r = dm_register_target(&cache_target); if (r) { - kmem_cache_destroy(migration_cache); - return r; + goto err; }
return 0; + +err: + kmem_cache_destroy(migration_cache); + kmem_cache_destroy(btracker_work_cache); + return r; }
static void __exit dm_cache_exit(void) { dm_unregister_target(&cache_target); kmem_cache_destroy(migration_cache); + kmem_cache_destroy(btracker_work_cache); }
module_init(dm_cache_init);