From f44aebcc566d1d6275f7191867b9633dc11de2ee Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Wed, 15 Jul 2009 15:49:52 -0400 Subject: inotify: use GFP_NOFS under potential memory pressure inotify can have a watchs removed under filesystem reclaim. ================================= [ INFO: inconsistent lock state ] 2.6.31-rc2 #16 --------------------------------- inconsistent {IN-RECLAIM_FS-W} -> {RECLAIM_FS-ON-W} usage. khubd/217 [HC0[0]:SC0[0]:HE1:SE1] takes: (iprune_mutex){+.+.?.}, at: [] invalidate_inodes+0x20/0xe3 {IN-RECLAIM_FS-W} state was registered at: [] __lock_acquire+0x2c9/0xac4 [] lock_acquire+0x9f/0xc2 [] __mutex_lock_common+0x2d/0x323 [] mutex_lock_nested+0x2e/0x36 [] shrink_icache_memory+0x38/0x1b2 [] shrink_slab+0xe2/0x13c [] kswapd+0x3d1/0x55d [] kthread+0x66/0x6b [] kernel_thread_helper+0x7/0x10 [] 0xffffffff Two things are needed to fix this. First we need a method to tell fsnotify_create_event() to use GFP_NOFS and second we need to stop using one global IN_IGNORED event and allocate them one at a time. This solves current issues with multiple IN_IGNORED on a queue having tail drop problems and simplifies the allocations since we don't have to worry about two tasks opperating on the IGNORED event concurrently. Signed-off-by: Eric Paris --- fs/notify/fsnotify.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'fs/notify/fsnotify.c') diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index ec2f7bd7681..037e878e03f 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -159,7 +159,9 @@ void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, const if (!group->ops->should_send_event(group, to_tell, mask)) continue; if (!event) { - event = fsnotify_create_event(to_tell, mask, data, data_is, file_name, cookie); + event = fsnotify_create_event(to_tell, mask, data, + data_is, file_name, cookie, + GFP_KERNEL); /* shit, we OOM'd and now we can't tell, maybe * someday someone else will want to do something * here */ -- cgit v1.2.3