mm/page_alloc: prevent concurrent updaters of pcp ->batch and ->high

Because we are going to rely upon a careful transision between old and new
->high and ->batch values using memory barriers and will remove
stop_machine(), we need to prevent multiple updaters from interweaving
their memory writes.

Add a simple mutex to protect both update loops.

Signed-off-by: Cody P Schafer <[email protected]>
Cc: Gilad Ben-Yossef <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Pekka Enberg <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions