diff options
| author | Lars Ellenberg <lars.ellenberg@linbit.com> | 2011-02-23 12:39:46 +0100 |
|---|---|---|
| committer | Philipp Reisner <philipp.reisner@linbit.com> | 2012-05-09 15:17:02 +0200 |
| commit | 4281808fb3580c381a23cceb0a29ced92d570a5f (patch) | |
| tree | b561a60dc382305bba499ae0e12c6e0573a3df06 /drivers/block/drbd | |
| parent | 0e8488ade26b4b16a9745aa15ecb88c3fb1cb953 (diff) | |
drbd: add page pool to be used for meta data IO
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Diffstat (limited to 'drivers/block/drbd')
| -rw-r--r-- | drivers/block/drbd/drbd_int.h | 23 | ||||
| -rw-r--r-- | drivers/block/drbd/drbd_main.c | 9 |
2 files changed, 31 insertions, 1 deletions
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index 6586053429b4..685ed4cca173 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -1496,11 +1496,32 @@ extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ extern mempool_t *drbd_request_mempool; extern mempool_t *drbd_ee_mempool; -extern struct page *drbd_pp_pool; /* drbd's page pool */ +/* drbd's page pool, used to buffer data received from the peer, + * or data requested by the peer. + * + * This does not have an emergency reserve. + * + * When allocating from this pool, it first takes pages from the pool. + * Only if the pool is depleted will try to allocate from the system. + * + * The assumption is that pages taken from this pool will be processed, + * and given back, "quickly", and then can be recycled, so we can avoid + * frequent calls to alloc_page(), and still will be able to make progress even + * under memory pressure. + */ +extern struct page *drbd_pp_pool; extern spinlock_t drbd_pp_lock; extern int drbd_pp_vacant; extern wait_queue_head_t drbd_pp_wait; +/* We also need a standard (emergency-reserve backed) page pool + * for meta data IO (activity log, bitmap). + * We can keep it global, as long as it is used as "N pages at a time". + * 128 should be plenty, currently we probably can get away with as few as 1. + */ +#define DRBD_MIN_POOL_PAGES 128 +extern mempool_t *drbd_md_io_page_pool; + extern rwlock_t global_state_lock; extern struct drbd_conf *drbd_new_device(unsigned int minor); diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index d830116781f9..ed264c92c3af 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -139,6 +139,7 @@ struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ mempool_t *drbd_request_mempool; mempool_t *drbd_ee_mempool; +mempool_t *drbd_md_io_page_pool; /* I do not use a standard mempool, because: 1) I want to hand out the pre-allocated objects first. @@ -3264,6 +3265,8 @@ static void drbd_destroy_mempools(void) /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */ + if (drbd_md_io_page_pool) + mempool_destroy(drbd_md_io_page_pool); if (drbd_ee_mempool) mempool_destroy(drbd_ee_mempool); if (drbd_request_mempool) @@ -3277,6 +3280,7 @@ static void drbd_destroy_mempools(void) if (drbd_al_ext_cache) kmem_cache_destroy(drbd_al_ext_cache); + drbd_md_io_page_pool = NULL; drbd_ee_mempool = NULL; drbd_request_mempool = NULL; drbd_ee_cache = NULL; @@ -3300,6 +3304,7 @@ static int drbd_create_mempools(void) drbd_bm_ext_cache = NULL; drbd_al_ext_cache = NULL; drbd_pp_pool = NULL; + drbd_md_io_page_pool = NULL; /* caches */ drbd_request_cache = kmem_cache_create( @@ -3323,6 +3328,10 @@ static int drbd_create_mempools(void) goto Enomem; /* mempools */ + drbd_md_io_page_pool = mempool_create_page_pool(DRBD_MIN_POOL_PAGES, 0); + if (drbd_md_io_page_pool == NULL) + goto Enomem; + drbd_request_mempool = mempool_create(number, mempool_alloc_slab, mempool_free_slab, drbd_request_cache); if (drbd_request_mempool == NULL) |