aabb8fdb41
fs: avoid I_NEW inodes
...
To be on the safe side, it should be less fragile to exclude I_NEW inodes
from inode list scans by default (unless there is an important reason to
have them).
Normally they will get excluded (eg. by zero refcount or writecount etc),
however it is a bit fragile for list walkers to know exactly what parts of
the inode state is set up and valid to test when in I_NEW. So along these
lines, move I_NEW checks upward as well (sometimes taking I_FREEING etc
checks with them too -- this shouldn't be a problem should it?)
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27 14:44:05 -04:00
f04b30de3c
inotify: fix GFP_KERNEL related deadlock
...
Enhanced lockdep coverage of __GFP_NOFS turned up this new lockdep
assert:
[ 1093.677775]
[ 1093.677781] =================================
[ 1093.680031] [ INFO: inconsistent lock state ]
[ 1093.680031] 2.6.29-rc5-tip-01504-gb49eca1-dirty #1
[ 1093.680031] ---------------------------------
[ 1093.680031] inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
[ 1093.680031] kswapd0/308 [HC0[0]:SC0[0]:HE1:SE1] takes:
[ 1093.680031] (&inode->inotify_mutex){+.+.?.}, at: [<c0205942>] inotify_inode_is_dead+0x20/0x80
[ 1093.680031] {RECLAIM_FS-ON-W} state was registered at:
[ 1093.680031] [<c01696b9>] mark_held_locks+0x43/0x5b
[ 1093.680031] [<c016baa4>] lockdep_trace_alloc+0x6c/0x6e
[ 1093.680031] [<c01cf8b0>] kmem_cache_alloc+0x20/0x150
[ 1093.680031] [<c040d0ec>] idr_pre_get+0x27/0x6c
[ 1093.680031] [<c02056e3>] inotify_handle_get_wd+0x25/0xad
[ 1093.680031] [<c0205f43>] inotify_add_watch+0x7a/0x129
[ 1093.680031] [<c020679e>] sys_inotify_add_watch+0x20f/0x250
[ 1093.680031] [<c010389e>] sysenter_do_call+0x12/0x35
[ 1093.680031] [<ffffffff>] 0xffffffff
[ 1093.680031] irq event stamp: 60417
[ 1093.680031] hardirqs last enabled at (60417): [<c018d5f5>] call_rcu+0x53/0x59
[ 1093.680031] hardirqs last disabled at (60416): [<c018d5b9>] call_rcu+0x17/0x59
[ 1093.680031] softirqs last enabled at (59656): [<c0146229>] __do_softirq+0x157/0x16b
[ 1093.680031] softirqs last disabled at (59651): [<c0106293>] do_softirq+0x74/0x15d
[ 1093.680031]
[ 1093.680031] other info that might help us debug this:
[ 1093.680031] 2 locks held by kswapd0/308:
[ 1093.680031] #0 : (shrinker_rwsem){++++..}, at: [<c01b0502>] shrink_slab+0x36/0x189
[ 1093.680031] #1 : (&type->s_umount_key#4){+++++.}, at: [<c01e6d77>] shrink_dcache_memory+0x110/0x1fb
[ 1093.680031]
[ 1093.680031] stack backtrace:
[ 1093.680031] Pid: 308, comm: kswapd0 Not tainted 2.6.29-rc5-tip-01504-gb49eca1-dirty #1
[ 1093.680031] Call Trace:
[ 1093.680031] [<c016947a>] valid_state+0x12a/0x13d
[ 1093.680031] [<c016954e>] mark_lock+0xc1/0x1e9
[ 1093.680031] [<c016a5b4>] ? check_usage_forwards+0x0/0x3f
[ 1093.680031] [<c016ab74>] __lock_acquire+0x2c6/0xac8
[ 1093.680031] [<c01688d9>] ? register_lock_class+0x17/0x228
[ 1093.680031] [<c016b3d3>] lock_acquire+0x5d/0x7a
[ 1093.680031] [<c0205942>] ? inotify_inode_is_dead+0x20/0x80
[ 1093.680031] [<c08824c4>] __mutex_lock_common+0x3a/0x4cb
[ 1093.680031] [<c0205942>] ? inotify_inode_is_dead+0x20/0x80
[ 1093.680031] [<c08829ed>] mutex_lock_nested+0x2e/0x36
[ 1093.680031] [<c0205942>] ? inotify_inode_is_dead+0x20/0x80
[ 1093.680031] [<c0205942>] inotify_inode_is_dead+0x20/0x80
[ 1093.680031] [<c01e6672>] dentry_iput+0x90/0xc2
[ 1093.680031] [<c01e67a3>] d_kill+0x21/0x45
[ 1093.680031] [<c01e6a46>] __shrink_dcache_sb+0x27f/0x355
[ 1093.680031] [<c01e6dc5>] shrink_dcache_memory+0x15e/0x1fb
[ 1093.680031] [<c01b05ed>] shrink_slab+0x121/0x189
[ 1093.680031] [<c01b0d12>] kswapd+0x39f/0x561
[ 1093.680031] [<c01ae499>] ? isolate_pages_global+0x0/0x233
[ 1093.680031] [<c0157eae>] ? autoremove_wake_function+0x0/0x43
[ 1093.680031] [<c01b0973>] ? kswapd+0x0/0x561
[ 1093.680031] [<c0157daf>] kthread+0x41/0x82
[ 1093.680031] [<c0157d6e>] ? kthread+0x0/0x82
[ 1093.680031] [<c01043ab>] kernel_thread_helper+0x7/0x10
inotify_handle_get_wd() does idr_pre_get() which does a
kmem_cache_alloc() without __GFP_FS - and is hence deadlockable under
extreme MM pressure.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: MinChan Kim <minchan.kim@gmail.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-18 15:37:56 -08:00
272eb01485
filesystem notification: create fs/notify to contain all fs notification
...
Creating a generic filesystem notification interface, fsnotify, which will be
used by inotify, dnotify, and eventually fanotify is really starting to
clutter the fs directory. This patch simply moves inotify and dnotify into
fs/notify/inotify and fs/notify/dnotify respectively to make both current fs/
and future notification tidier.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:43 -05:00
Nick Piggin
Ingo Molnar
Eric Paris