[PATCH] vfs: fix: don't increase bio_slab_max if krealloc() fails

[PATCH] vfs: fix: don't increase bio_slab_max if krealloc() fails

[Anna Leuschner]

bio.c: fix: don't increase bio_slab_max if krealloc() of bio_slabs fails

Signed-off-by: Anna Leuschner <anna.m.leuschner@gmail.com>
---
 fs/bio.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/bio.c b/fs/bio.c
index 9298c65..b96fc6c 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -75,6 +75,7 @@ static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size)
 	unsigned int sz = sizeof(struct bio) + extra_size;
 	struct kmem_cache *slab = NULL;
 	struct bio_slab *bslab, *new_bio_slabs;
+	unsigned int new_bio_slab_max;
 	unsigned int i, entry = -1;
 
 	mutex_lock(&bio_slab_lock);
@@ -97,12 +98,13 @@ static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size)
 		goto out_unlock;
 
 	if (bio_slab_nr == bio_slab_max && entry == -1) {
-		bio_slab_max <<= 1;
+		new_bio_slab_max = bio_slab_max << 1;
 		new_bio_slabs = krealloc(bio_slabs,
-					 bio_slab_max * sizeof(struct bio_slab),
+					 new_bio_slab_max * sizeof(struct bio_slab),
 					 GFP_KERNEL);
 		if (!new_bio_slabs)
 			goto out_unlock;
+		bio_slab_max = new_bio_slab_max;
 		bio_slabs = new_bio_slabs;
 	}
 	if (entry == -1)
-- 
1.7.10.4

Re: [PATCH] vfs: fix: don't increase bio_slab_max if krealloc() fails

[Jens Axboe]

On 2012-10-21 22:33, Anna Leuschner wrote:
> bio.c: fix: don't increase bio_slab_max if krealloc() of bio_slabs fails

You failed the "how to write a commit message" part of the patch :-)
The commit message should talk about WHY a change is necessary, not
HOW it is done. The latter should be obvious from looking at the code
change.

So, in other words, please describe why the change is useful or needed.
Then resend.

-- 
Jens Axboe