From 98bc3149fad639c8f50c7110b961a2a2fe085eed Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Tue, 22 Mar 2011 11:00:46 -0400 Subject: [PATCH] Btrfs: don't allocate dip->csums when doing writes When doing direct writes we store the checksums in the ordered sum stuff in the ordered extent for writing them when the write completes, so we don't even use the dip->csums array. So if we're writing, don't bother allocating dip->csums since we won't use it anyway. Thanks, Signed-off-by: Josef Bacik --- fs/btrfs/inode.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index e010000..570cd44 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5944,6 +5944,7 @@ static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip, int nr_pages = 0; u32 *csums = dip->csums; int ret = 0; + int write = rw & REQ_WRITE; bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS); if (!bio) @@ -5980,7 +5981,8 @@ static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip, goto out_err; } - if (!skip_sum) + /* Write's use the ordered csums */ + if (!write && !skip_sum) csums = csums + nr_pages; start_sector += submit_len >> 9; file_offset += submit_len; @@ -6048,7 +6050,8 @@ static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode, } dip->csums = NULL; - if (!skip_sum) { + /* Write's use the ordered csum stuff, so we don't need dip->csums */ + if (!write && !skip_sum) { dip->csums = kmalloc(sizeof(u32) * bio->bi_vcnt, GFP_NOFS); if (!dip->csums) { kfree(dip); -- 2.7.4