Omar Sandoval 93781325da lockdep: fix fs_reclaim annotation ... While revisiting my Btrfs swapfile series [1], I introduced a situation in which reclaim would lock i_rwsem, and even though the swapon() path clearly made GFP_KERNEL allocations while holding i_rwsem, I got no complaints from lockdep. It turns out that the rework of the fs_reclaim annotation was broken: if the current task has PF_MEMALLOC set, we don't acquire the dummy fs_reclaim lock, but when reclaiming we always check this _after_ we've just set the PF_MEMALLOC flag. In most cases, we can fix this by moving the fs_reclaim_{acquire,release}() outside of the memalloc_noreclaim_{save,restore}(), althought kswapd is slightly different. After applying this, I got the expected lockdep splats. 1: https://lwn.net/Articles/625412/ Link: http://lkml.kernel.org/r/9f8aa70652a98e98d7c4de0fc96a4addcee13efe.1523778026.git.osandov@fb.com Fixes: d92a8cfcb3 ("locking/lockdep: Rework FS_RECLAIM annotation") Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2018-06-07 17:34:35 -07:00
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autogroup.h
clock.h
coredump.h
cpufreq.h	sched/cpufreq: Provide migration hint	2018-03-09 07:59:20 +01:00
cputime.h
deadline.h	sched/headers: Simplify and clean up header usage in the scheduler	2018-03-04 12:39:29 +01:00
debug.h
hotplug.h
idle.h
init.h
isolation.h	sched/isolation: Isolate workqueues when "nohz_full=" is set	2018-02-21 09:49:08 +01:00
jobctl.h
loadavg.h
mm.h	lockdep: fix fs_reclaim annotation	2018-06-07 17:34:35 -07:00
nohz.h	sched/nohz: Clean up nohz enter/exit	2018-03-09 07:59:19 +01:00
numa_balancing.h
prio.h
rt.h
signal.h	sched/core: Introduce set_special_state()	2018-05-04 07:54:54 +02:00
stat.h
sysctl.h
task_stack.h
task.h
topology.h
user.h	efivarfs: Limit the rate for non-root to read files	2018-02-22 10:21:02 -08:00
wake_q.h
xacct.h