AcoSail/kernel_optimize_test
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kernel_optimize_test/fs/jbd2
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Michal Hocko f2db19719a jbd2: get rid of superfluous __GFP_REPEAT 
jbd2_alloc is explicit about its allocation preferences wrt.  the
allocation size.  Sub page allocations go to the slab allocator and
larger are using either the page allocator or vmalloc.  This is all good
but the logic is unnecessarily complex.

1) as per Ted, the vmalloc fallback is a left-over:

 : jbd2_alloc is only passed in the bh->b_size, which can't be PAGE_SIZE, so
 : the code path that calls vmalloc() should never get called.  When we
 : conveted jbd2_alloc() to suppor sub-page size allocations in commit
 : d2eecb0393, there was an assumption that it could be called with a size
 : greater than PAGE_SIZE, but that's certaily not true today.

Moreover vmalloc allocation might even lead to a deadlock because the
callers expect GFP_NOFS context while vmalloc is GFP_KERNEL.

2) __GFP_REPEAT for requests <= PAGE_ALLOC_COSTLY_ORDER is ignored
   since the flag was introduced.

Let's simplify the code flow and use the slab allocator for sub-page
requests and the page allocator for others.  Even though order > 0 is
not currently used as per above leave that option open.

Link: http://lkml.kernel.org/r/1464599699-30131-18-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-24 17:23:52 -07:00
..
checkpoint.c jbd2: fix checkpoint list cleanup 2015-10-17 22:35:09 -04:00
commit.c jbd2: add support for avoiding data writes during transaction commits 2016-04-24 00:56:07 -04:00
journal.c jbd2: get rid of superfluous __GFP_REPEAT 2016-06-24 17:23:52 -07:00
Kconfig jbd2: remove debug dependency on debug_fs and update Kconfig help text 2013-06-12 23:07:51 -04:00
Makefile
recovery.c Merge branch 'master' into for-next 2016-04-18 11:18:55 +02:00
revoke.c jbd2: unify revoke and tag block checksum handling 2016-02-22 23:19:09 -05:00
transaction.c Fix a number of bugs, most notably a potential stale data exposure 2016-05-24 12:55:26 -07:00