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| author | Chris Wilson <chris@chris-wilson.co.uk> | 2016-07-23 19:27:50 +0100 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2016-09-14 12:57:43 -0700 |
| commit | 12adfd882c5f37548acaba4f043a158b3c54468b (patch) | |
| tree | 83c46e074a1044db2364cd712111550c994c3bc8 /kernel/rcu | |
| parent | 3563a438f124cb0b8cfd350c86de2f26c63d8837 (diff) | |
| download | linux-12adfd882c5f37548acaba4f043a158b3c54468b.tar.gz linux-12adfd882c5f37548acaba4f043a158b3c54468b.tar.bz2 linux-12adfd882c5f37548acaba4f043a158b3c54468b.zip | |
list: Expand list_first_entry_or_null()
Due to the use of READ_ONCE() in list_empty() the compiler cannot
optimise !list_empty() ? list_first_entry() : NULL very well. By
manually expanding list_first_entry_or_null() we can take advantage of
the READ_ONCE() to avoid the list element changing under the test while
the compiler can generate smaller code.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Josef Bacik <jbacik@fb.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcu')
0 files changed, 0 insertions, 0 deletions