From b98938c373117043598002f197200d7ed08acd49 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Mon, 4 Feb 2008 22:28:36 -0800 Subject: [PATCH] bufferhead: revert constructor removal The constructor for buffer_head slabs was removed recently. We need the constructor back in slab defrag in order to insure that slab objects always have a definite state even before we allocated them. I think we mistakenly merged the removal of the constuctor into a cleanup patch. You (ie: akpm) had a test that showed that the removal of the constructor led to a small regression. The prior state makes things easier for slab defrag. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Christoph Lameter Cc: Nick Piggin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/buffer.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index 1de921484eac..826baf4f04bc 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -3153,7 +3153,7 @@ static void recalc_bh_state(void) struct buffer_head *alloc_buffer_head(gfp_t gfp_flags) { - struct buffer_head *ret = kmem_cache_zalloc(bh_cachep, + struct buffer_head *ret = kmem_cache_alloc(bh_cachep, set_migrateflags(gfp_flags, __GFP_RECLAIMABLE)); if (ret) { INIT_LIST_HEAD(&ret->b_assoc_buffers); @@ -3241,12 +3241,24 @@ int bh_submit_read(struct buffer_head *bh) } EXPORT_SYMBOL(bh_submit_read); +static void +init_buffer_head(struct kmem_cache *cachep, void *data) +{ + struct buffer_head *bh = data; + + memset(bh, 0, sizeof(*bh)); + INIT_LIST_HEAD(&bh->b_assoc_buffers); +} + void __init buffer_init(void) { int nrpages; - bh_cachep = KMEM_CACHE(buffer_head, - SLAB_RECLAIM_ACCOUNT|SLAB_PANIC|SLAB_MEM_SPREAD); + bh_cachep = kmem_cache_create("buffer_head", + sizeof(struct buffer_head), 0, + (SLAB_RECLAIM_ACCOUNT|SLAB_PANIC| + SLAB_MEM_SPREAD), + init_buffer_head); /* * Limit the bh occupancy to 10% of ZONE_NORMAL -- GitLab