search for: find_lock_delalloc_range

So both Liu and I made huge messes of find_lock_delalloc_range trying to fix stuff, me first by fixing extent size, then him by fixing something I broke and then me again telling him to fix it a different way. So this is obviously a candidate for some testing. This patch adds a pseudo fs so we can allocate fake inodes for tests that need an inode or pages....

...[page] So find_delalloc_range will return with delalloc_start as 0 and end as 128mb, and then we will notice that delalloc_start < *start and adjust it up, but not adjust delalloc_end up, so things go sideways. To fix this we need to not limit the max bytes in find_delalloc_range, but in find_lock_delalloc_range and that way we don''t end up with this confusion. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> --- fs/btrfs/extent_io.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index b48942f..2bf6f46 1...

...x0/0x31 Jul 8 11:49:40 xback2 kernel: [74920.681032] [<ffffffffa0430cf9>] lock_page+0x3a/0x3e [btrfs] Jul 8 11:49:40 xback2 kernel: [74920.681032] [<ffffffffa04310a6>] lock_delalloc_pages+0xad/0x1af [btrfs] Jul 8 11:49:40 xback2 kernel: [74920.681032] [<ffffffffa0432f7c>] find_lock_delalloc_range.constprop.9+0xc8/0x1ba [btrfs] Jul 8 11:49:40 xback2 kernel: [74920.681032] [<ffffffffa0433866>] __extent_writepage+0x15c/0x582 [btrfs] Jul 8 11:49:40 xback2 kernel: [74920.681032] [<ffffffff8122d488>] ? radix_tree_gang_lookup_tag_slot+0x81/0xa2 Jul 8 11:49:40 xback2 kernel: [749...

...[btrfs] [ 68.127553] [<ffffffffa048862f>] ? free_extent_buffer+0x4f/0xa0 [btrfs] [ 68.127598] [<ffffffffa04716d6>] run_delalloc_nocow+0x436/0xaf0 [btrfs] [ 68.127641] [<ffffffffa0472180>] run_delalloc_range+0x320/0x390 [btrfs] [ 68.127685] [<ffffffffa04854c1>] ? find_lock_delalloc_range.constprop.44+0x1d1/0x1f0 [btrfs] [ 68.127735] [<ffffffffa0487044>] __extent_writepage+0x354/0x7b0 [btrfs] [ 68.127772] [<ffffffff81122645>] ? find_get_pages_tag+0x105/0x180 [ 68.127813] [<ffffffffa0487722>] extent_write_cache_pages.isra.32.constprop.48+0x282/0x3e0 [btrfs]...

Hi Linus, My for-linus branch has a one line fix: git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs.git for-linus Sage hit a deadlock with ceph on btrfs, and Josef tracked it down to a regression in our initial rc1 pull. When doing nocow writes we were sometimes starting a transaction with locks held. Josef Bacik (1) commits (+1/-0): Btrfs: release path before starting

We need an smb_mb() before waitqueue_active to avoid missing wakeups. Before Mitch was hitting a deadlock between the ordered flushers and the transaction commit because the ordered flushers were waiting for more refs and were never woken up, so those smp_mb()''s are the most important. Everything else I added for correctness sake and to avoid getting bitten by this again somewhere else.