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/notification.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'fs/notify/notification.c') diff --git a/fs/notify/notification.c b/fs/notify/notification.c index 2b20feaf263a..521368574e97 100644 --- a/fs/notify/notification.c +++ b/fs/notify/notification.c @@ -153,7 +153,7 @@ static bool event_compare(struct fsnotify_event *old, struct fsnotify_event *new return true; break; case (FSNOTIFY_EVENT_NONE): - return true; + return false; }; } return false; @@ -345,18 +345,19 @@ static void initialize_event(struct fsnotify_event *event) * @name the filename, if available */ struct fsnotify_event *fsnotify_create_event(struct inode *to_tell, __u32 mask, void *data, - int data_type, const char *name, u32 cookie) + int data_type, const char *name, u32 cookie, + gfp_t gfp) { struct fsnotify_event *event; - event = kmem_cache_alloc(fsnotify_event_cachep, GFP_KERNEL); + event = kmem_cache_alloc(fsnotify_event_cachep, gfp); if (!event) return NULL; initialize_event(event); if (name) { - event->file_name = kstrdup(name, GFP_KERNEL); + event->file_name = kstrdup(name, gfp); if (!event->file_name) { kmem_cache_free(fsnotify_event_cachep, event); return NULL; -- cgit v1.2.3