• David Rientjes's avatar
    mm, thp: abort compaction if migration page cannot be charged to memcg · 4bf2bba3
    David Rientjes authored
    If page migration cannot charge the temporary page to the memcg,
    migrate_pages() will return -ENOMEM.  This isn't considered in memory
    compaction however, and the loop continues to iterate over all
    pageblocks trying to isolate and migrate pages.  If a small number of
    very large memcgs happen to be oom, however, these attempts will mostly
    be futile leading to an enormous amout of cpu consumption due to the
    page migration failures.
    
    This patch will short circuit and fail memory compaction if
    migrate_pages() returns -ENOMEM.  COMPACT_PARTIAL is returned in case
    some migrations were successful so that the page allocator will retry.
    Signed-off-by: default avatarDavid Rientjes <rientjes@google.com>
    Acked-by: default avatarMel Gorman <mgorman@suse.de>
    Cc: Minchan Kim <minchan@kernel.org>
    Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
    Cc: Rik van Riel <riel@redhat.com>
    Cc: Andrea Arcangeli <aarcange@redhat.com>
    Cc: <stable@vger.kernel.org>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    4bf2bba3
compaction.c 23.7 KB