I think this would be slightly better than your proposal. Andrew, could you fold it into the original mm-compaction-simplify-__alloc_pages_direct_compact-feedback-interface.patch patch? --- >From 434bc8b6f3787724327499998c4fe651e8ce5d68 Mon Sep 17 00:00:00 2001 From: Michal Hocko <[email protected]> Date: Thu, 12 May 2016 08:10:33 +0200 Subject: [PATCH] mmotm: mm-compaction-simplify-__alloc_pages_direct_compact-feedback-interface-fix
Arnd has reported the following compilation warning: mm/page_alloc.c: In function '__alloc_pages_nodemask': mm/page_alloc.c:3651:6: error: 'compact_result' may be used uninitialized in this function [-Werror=maybe-uninitialized] This should be a false positive TRANSPARENT_HUGEPAGE depends on COMPACTION so is_thp_gfp_mask shouldn't be true. GFP_TRANSHUGE is a bit tricky and somebody might be using this accidently. Make sure that compact_result is defined also for !CONFIG_COMPACT and set it to COMPACT_SKIPPED because the compaction was really withdrawn. Reported-by: Arnd Bergmann <[email protected]> Signed-off-by: Michal Hocko <[email protected]> --- mm/page_alloc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 4950d01ff935..0d9008042efa 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3300,6 +3300,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, unsigned int alloc_flags, const struct alloc_context *ac, enum migrate_mode mode, enum compact_result *compact_result) { + *compact_result = COMPACT_SKIPPED; return NULL; } -- 2.8.1 -- Michal Hocko SUSE Labs
