mm, compaction: simplify contended compaction handling

[cascardo/linux.git] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 26c6fe7..ea759b9 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3099,14 +3099,13 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
                enum compact_priority prio, enum compact_result *compact_result)
 {
        struct page *page;
-       int contended_compaction;
 
        if (!order)
                return NULL;
 
        current->flags |= PF_MEMALLOC;
        *compact_result = try_to_compact_pages(gfp_mask, order, alloc_flags, ac,
-                                               prio, &contended_compaction);
+                                                                       prio);
        current->flags &= ~PF_MEMALLOC;
 
        if (*compact_result <= COMPACT_INACTIVE)
@@ -3135,24 +3134,6 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
         */
        count_vm_event(COMPACTFAIL);
 
-       /*
-        * In all zones where compaction was attempted (and not
-        * deferred or skipped), lock contention has been detected.
-        * For THP allocation we do not want to disrupt the others
-        * so we fallback to base pages instead.
-        */
-       if (contended_compaction == COMPACT_CONTENDED_LOCK)
-               *compact_result = COMPACT_CONTENDED;
-
-       /*
-        * If compaction was aborted due to need_resched(), we do not
-        * want to further increase allocation latency, unless it is
-        * khugepaged trying to collapse.
-        */
-       if (contended_compaction == COMPACT_CONTENDED_SCHED
-               && !(current->flags & PF_KTHREAD))
-               *compact_result = COMPACT_CONTENDED;
-
        cond_resched();
 
        return NULL;
@@ -3547,13 +3528,6 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
                        if (compact_result == COMPACT_DEFERRED)
                                goto nopage;
 
-                       /*
-                        * Compaction is contended so rather back off than cause
-                        * excessive stalls.
-                        */
-                       if (compact_result == COMPACT_CONTENDED)
-                               goto nopage;
-
                        /*
                         * Looks like reclaim/compaction is worth trying, but
                         * sync compaction could be very expensive, so keep