From 0a79cdad5eb213b3a629e624565b1b3bf9192b7c Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Fri, 28 Dec 2018 00:35:48 -0800 Subject: mm: use alloc_flags to record if kswapd can wake This is a preparation patch that copies the GFP flag __GFP_KSWAPD_RECLAIM into alloc_flags. This is a preparation patch only that avoids having to pass gfp_mask through a long callchain in a future patch. Note that the setting in the fast path happens in alloc_flags_nofragment() and it may be claimed that this has nothing to do with ALLOC_NO_FRAGMENT. That's true in this patch but is not true later so it's done now for easier review to show where the flag needs to be recorded. No functional change. [mgorman@techsingularity.net: ALLOC_KSWAPD flag needs to be applied in the !CONFIG_ZONE_DMA32 case] Link: http://lkml.kernel.org/r/20181126143503.GO23260@techsingularity.net Link: http://lkml.kernel.org/r/20181123114528.28802-4-mgorman@techsingularity.net Signed-off-by: Mel Gorman Reviewed-by: Andrew Morton Cc: Andrea Arcangeli Cc: David Rientjes Cc: Michal Hocko Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 2046e333ea8f..32b3e121a388 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3268,7 +3268,6 @@ static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone) } #endif /* CONFIG_NUMA */ -#ifdef CONFIG_ZONE_DMA32 /* * The restriction on ZONE_DMA32 as being a suitable zone to use to avoid * fragmentation is subtle. If the preferred zone was HIGHMEM then @@ -3278,10 +3277,16 @@ static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone) * fragmentation between the Normal and DMA32 zones. */ static inline unsigned int -alloc_flags_nofragment(struct zone *zone) +alloc_flags_nofragment(struct zone *zone, gfp_t gfp_mask) { + unsigned int alloc_flags = 0; + + if (gfp_mask & __GFP_KSWAPD_RECLAIM) + alloc_flags |= ALLOC_KSWAPD; + +#ifdef CONFIG_ZONE_DMA32 if (zone_idx(zone) != ZONE_NORMAL) - return 0; + goto out; /* * If ZONE_DMA32 exists, assume it is the one after ZONE_NORMAL and @@ -3290,17 +3295,12 @@ alloc_flags_nofragment(struct zone *zone) */ BUILD_BUG_ON(ZONE_NORMAL - ZONE_DMA32 != 1); if (nr_online_nodes > 1 && !populated_zone(--zone)) - return 0; + goto out; - return ALLOC_NOFRAGMENT; -} -#else -static inline unsigned int -alloc_flags_nofragment(struct zone *zone) -{ - return 0; +out: +#endif /* CONFIG_ZONE_DMA32 */ + return alloc_flags; } -#endif /* * get_page_from_freelist goes through the zonelist trying to allocate @@ -3939,6 +3939,9 @@ gfp_to_alloc_flags(gfp_t gfp_mask) } else if (unlikely(rt_task(current)) && !in_interrupt()) alloc_flags |= ALLOC_HARDER; + if (gfp_mask & __GFP_KSWAPD_RECLAIM) + alloc_flags |= ALLOC_KSWAPD; + #ifdef CONFIG_CMA if (gfpflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE) alloc_flags |= ALLOC_CMA; @@ -4170,7 +4173,7 @@ retry_cpuset: if (!ac->preferred_zoneref->zone) goto nopage; - if (gfp_mask & __GFP_KSWAPD_RECLAIM) + if (alloc_flags & ALLOC_KSWAPD) wake_all_kswapds(order, gfp_mask, ac); /* @@ -4228,7 +4231,7 @@ retry_cpuset: retry: /* Ensure kswapd doesn't accidentally go to sleep as long as we loop */ - if (gfp_mask & __GFP_KSWAPD_RECLAIM) + if (alloc_flags & ALLOC_KSWAPD) wake_all_kswapds(order, gfp_mask, ac); reserve_flags = __gfp_pfmemalloc_flags(gfp_mask); @@ -4451,7 +4454,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, * Forbid the first pass from falling back to types that fragment * memory until all local zones are considered. */ - alloc_flags |= alloc_flags_nofragment(ac.preferred_zoneref->zone); + alloc_flags |= alloc_flags_nofragment(ac.preferred_zoneref->zone, gfp_mask); /* First allocation attempt */ page = get_page_from_freelist(alloc_mask, order, alloc_flags, &ac); -- cgit v1.2.3