From fcd403aff643a120dbb3f1851337df5353ac8970 Mon Sep 17 00:00:00 2001 From: Artur Paszkiewicz Date: Tue, 11 Apr 2017 20:50:51 +0200 Subject: [PATCH] raid5-ppl: use a single mempool for ppl_io_unit and header_page Allocate both struct ppl_io_unit and its header_page from a shared mempool to avoid a possible deadlock. Implement allocate and free functions for the mempool, remove the second pool for allocating header_page. The header_pages are now freed with their io_units, not when the ppl bio completes. Also, use GFP_NOWAIT instead of GFP_ATOMIC for allocating ppl_io_unit because we can handle failed allocations and there is no reason to utilize emergency reserves. Suggested-by: NeilBrown Signed-off-by: Artur Paszkiewicz Signed-off-by: Shaohua Li --- drivers/md/raid5-ppl.c | 53 +++++++++++++++++++++++++++++------------- 1 file changed, 37 insertions(+), 16 deletions(-) diff --git a/drivers/md/raid5-ppl.c b/drivers/md/raid5-ppl.c index 4eb0ebcf9c29..5d25bebf3328 100644 --- a/drivers/md/raid5-ppl.c +++ b/drivers/md/raid5-ppl.c @@ -102,7 +102,6 @@ struct ppl_conf { struct kmem_cache *io_kc; mempool_t *io_pool; struct bio_set *bs; - mempool_t *meta_pool; /* used only for recovery */ int recovered_entries; @@ -197,25 +196,55 @@ ops_run_partial_parity(struct stripe_head *sh, struct raid5_percpu *percpu, return tx; } +static void *ppl_io_pool_alloc(gfp_t gfp_mask, void *pool_data) +{ + struct kmem_cache *kc = pool_data; + struct ppl_io_unit *io; + + io = kmem_cache_alloc(kc, gfp_mask); + if (!io) + return NULL; + + io->header_page = alloc_page(gfp_mask); + if (!io->header_page) { + kmem_cache_free(kc, io); + return NULL; + } + + return io; +} + +static void ppl_io_pool_free(void *element, void *pool_data) +{ + struct kmem_cache *kc = pool_data; + struct ppl_io_unit *io = element; + + __free_page(io->header_page); + kmem_cache_free(kc, io); +} + static struct ppl_io_unit *ppl_new_iounit(struct ppl_log *log, struct stripe_head *sh) { struct ppl_conf *ppl_conf = log->ppl_conf; struct ppl_io_unit *io; struct ppl_header *pplhdr; + struct page *header_page; - io = mempool_alloc(ppl_conf->io_pool, GFP_ATOMIC); + io = mempool_alloc(ppl_conf->io_pool, GFP_NOWAIT); if (!io) return NULL; + header_page = io->header_page; memset(io, 0, sizeof(*io)); + io->header_page = header_page; + io->log = log; INIT_LIST_HEAD(&io->log_sibling); INIT_LIST_HEAD(&io->stripe_list); atomic_set(&io->pending_stripes, 0); bio_init(&io->bio, io->biovec, PPL_IO_INLINE_BVECS); - io->header_page = mempool_alloc(ppl_conf->meta_pool, GFP_NOIO); pplhdr = page_address(io->header_page); clear_page(pplhdr); memset(pplhdr->reserved, 0xff, PPL_HDR_RESERVED); @@ -371,8 +400,6 @@ static void ppl_log_endio(struct bio *bio) if (bio->bi_error) md_error(ppl_conf->mddev, log->rdev); - mempool_free(io->header_page, ppl_conf->meta_pool); - list_for_each_entry_safe(sh, next, &io->stripe_list, log_list) { list_del_init(&sh->log_list); @@ -1007,7 +1034,6 @@ static void __ppl_exit_log(struct ppl_conf *ppl_conf) kfree(ppl_conf->child_logs); - mempool_destroy(ppl_conf->meta_pool); if (ppl_conf->bs) bioset_free(ppl_conf->bs); mempool_destroy(ppl_conf->io_pool); @@ -1113,25 +1139,20 @@ int ppl_init_log(struct r5conf *conf) ppl_conf->io_kc = KMEM_CACHE(ppl_io_unit, 0); if (!ppl_conf->io_kc) { - ret = -EINVAL; + ret = -ENOMEM; goto err; } - ppl_conf->io_pool = mempool_create_slab_pool(conf->raid_disks, ppl_conf->io_kc); + ppl_conf->io_pool = mempool_create(conf->raid_disks, ppl_io_pool_alloc, + ppl_io_pool_free, ppl_conf->io_kc); if (!ppl_conf->io_pool) { - ret = -EINVAL; + ret = -ENOMEM; goto err; } ppl_conf->bs = bioset_create(conf->raid_disks, 0); if (!ppl_conf->bs) { - ret = -EINVAL; - goto err; - } - - ppl_conf->meta_pool = mempool_create_page_pool(conf->raid_disks, 0); - if (!ppl_conf->meta_pool) { - ret = -EINVAL; + ret = -ENOMEM; goto err; } -- 2.20.1