From: Christoph Lameter Migrate flags must be set on slab creation as agreed upon when the antifrag logic was reviewed. Otherwise some slabs of a slabcache will end up in the unmovable and others in the reclaimable section depending on which flag was active when a new slab page was allocated. This likely slid in somehow when antifrag was merged. Remove it. The buffer_heads are always allocated with __GFP_RECLAIMABLE because the SLAB_RECLAIM_ACCOUNT option is set. The set_migrateflags() never had any effect there. Radix tree allocations are not directly reclaimable but they are allocated with __GFP_RECLAIMABLE set on each allocation. We now set SLAB_RECLAIM_ACCOUNT on radix tree slab creation making sure that radix tree slabs are consistently placed in the reclaimable section. Radix tree slabs will also be accounted as such. There is then no user left of set_migratepages. So remove it. Signed-off-by: Christoph Lameter Cc: Mel Gorman Signed-off-by: Andrew Morton --- fs/buffer.c | 3 +-- include/linux/gfp.h | 6 ------ lib/radix-tree.c | 9 ++++----- 3 files changed, 5 insertions(+), 13 deletions(-) diff -puN fs/buffer.c~remove-set_migrateflags fs/buffer.c --- a/fs/buffer.c~remove-set_migrateflags +++ a/fs/buffer.c @@ -3167,8 +3167,7 @@ static void recalc_bh_state(void) struct buffer_head *alloc_buffer_head(gfp_t gfp_flags) { - struct buffer_head *ret = kmem_cache_alloc(bh_cachep, - set_migrateflags(gfp_flags, __GFP_RECLAIMABLE)); + struct buffer_head *ret = kmem_cache_alloc(bh_cachep, gfp_flags); if (ret) { INIT_LIST_HEAD(&ret->b_assoc_buffers); get_cpu_var(bh_accounting).nr++; diff -puN include/linux/gfp.h~remove-set_migrateflags include/linux/gfp.h --- a/include/linux/gfp.h~remove-set_migrateflags +++ a/include/linux/gfp.h @@ -144,12 +144,6 @@ static inline enum zone_type gfp_zone(gf return base + ZONE_NORMAL; } -static inline gfp_t set_migrateflags(gfp_t gfp, gfp_t migrate_flags) -{ - BUG_ON((gfp & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK); - return (gfp & ~(GFP_MOVABLE_MASK)) | migrate_flags; -} - /* * There is only one page-allocator function, and two main namespaces to * it. The alloc_page*() variants return 'struct page *' and as such diff -puN lib/radix-tree.c~remove-set_migrateflags lib/radix-tree.c --- a/lib/radix-tree.c~remove-set_migrateflags +++ a/lib/radix-tree.c @@ -114,8 +114,7 @@ radix_tree_node_alloc(struct radix_tree_ } } if (ret == NULL) - ret = kmem_cache_alloc(radix_tree_node_cachep, - set_migrateflags(gfp_mask, __GFP_RECLAIMABLE)); + ret = kmem_cache_alloc(radix_tree_node_cachep, gfp_mask); BUG_ON(radix_tree_is_indirect_ptr(ret)); return ret; @@ -150,8 +149,7 @@ int radix_tree_preload(gfp_t gfp_mask) rtp = &__get_cpu_var(radix_tree_preloads); while (rtp->nr < ARRAY_SIZE(rtp->nodes)) { preempt_enable(); - node = kmem_cache_alloc(radix_tree_node_cachep, - set_migrateflags(gfp_mask, __GFP_RECLAIMABLE)); + node = kmem_cache_alloc(radix_tree_node_cachep, gfp_mask); if (node == NULL) goto out; preempt_disable(); @@ -1098,7 +1096,8 @@ void __init radix_tree_init(void) { radix_tree_node_cachep = kmem_cache_create("radix_tree_node", sizeof(struct radix_tree_node), 0, - SLAB_PANIC, radix_tree_node_ctor); + SLAB_PANIC | SLAB_RECLAIM_ACCOUNT, + radix_tree_node_ctor); radix_tree_init_maxindex(); hotcpu_notifier(radix_tree_callback, 0); } _