mm: add new mmgrab() helper

Apart from adding the helper function itself, the rest of the kernel is
converted mechanically using:

  git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)->mm_count);/mmgrab\(\1\);/'
  git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)\.mm_count);/mmgrab\(\&\1\);/'

This is needed for a later patch that hooks into the helper, but might
be a worthwhile cleanup on its own.

(Michal Hocko provided most of the kerneldoc comment.)

Link: http://lkml.kernel.org/r/20161218123229.22952-1-vegard.nossum@oracle.com
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Vegard Nossum 2017-02-27 14:30:07 -08:00 committed by Linus Torvalds
parent 522b837c67
commit f1f1007644
40 changed files with 65 additions and 43 deletions

View file

@ -994,7 +994,7 @@ cpu_init (void)
*/
ia64_setreg(_IA64_REG_CR_DCR, ( IA64_DCR_DP | IA64_DCR_DK | IA64_DCR_DX | IA64_DCR_DR
| IA64_DCR_DA | IA64_DCR_DD | IA64_DCR_LC));
atomic_inc(&init_mm.mm_count);
mmgrab(&init_mm);
current->active_mm = &init_mm;
BUG_ON(current->mm);