From: zhangkui Date: Thu, 2 Sep 2021 22:01:11 +0000 (-0700) Subject: mm/madvise: add MADV_WILLNEED to process_madvise() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=d5fffc5aff269717a035baa087630adca612a6c4;p=linux.git mm/madvise: add MADV_WILLNEED to process_madvise() There is a usecase in Android that an app process's memory is swapped out by process_madvise() with MADV_PAGEOUT, such as the memory is swapped to zram or a backing device. When the process is scheduled to running, like switch to foreground, multiple page faults may cause the app dropped frames. To reduce the problem, System Management Software can read-ahead memory of the process immediately when the app switches to forground. Calling process_madvise() with MADV_WILLNEED can meet this need. Link: https://lkml.kernel.org/r/20210804082010.12482-1-zhangkui@oppo.com Signed-off-by: zhangkui Cc: David Hildenbrand Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/madvise.c b/mm/madvise.c index 5c065bc8b5f6c..4a15a83031f6a 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -1048,6 +1048,7 @@ process_madvise_behavior_valid(int behavior) switch (behavior) { case MADV_COLD: case MADV_PAGEOUT: + case MADV_WILLNEED: return true; default: return false;