__GFP_HIGH aliases to ALLOC_HIGH but the name does not really hint what it means. As ALLOC_HIGH is internal to the allocator, rename it to ALLOC_MIN_RESERVE to document that the min reserves can be depleted. Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> --- mm/internal.h | 4 +++- mm/page_alloc.c | 8 ++++---- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index bcf75a8b032d..403e4386626d 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -736,7 +736,9 @@ unsigned int reclaim_clean_pages_from_list(struct zone *zone, #endif #define ALLOC_HARDER 0x10 /* try to alloc harder */ -#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */ +#define ALLOC_MIN_RESERVE 0x20 /* __GFP_HIGH set. Allow access to 50% + * of the min watermark. + */ #define ALLOC_CPUSET 0x40 /* check for correct cpuset */ #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */ #ifdef CONFIG_ZONE_DMA32 diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0745aedebb37..244c1e675dc8 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3976,7 +3976,7 @@ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, /* free_pages may go negative - that's OK */ free_pages -= __zone_watermark_unusable_free(z, order, alloc_flags); - if (alloc_flags & ALLOC_HIGH) + if (alloc_flags & ALLOC_MIN_RESERVE) min -= min / 2; if (unlikely(alloc_harder)) { @@ -4818,18 +4818,18 @@ gfp_to_alloc_flags(gfp_t gfp_mask) unsigned int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET; /* - * __GFP_HIGH is assumed to be the same as ALLOC_HIGH + * __GFP_HIGH is assumed to be the same as ALLOC_MIN_RESERVE * and __GFP_KSWAPD_RECLAIM is assumed to be the same as ALLOC_KSWAPD * to save two branches. */ - BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH); + BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_MIN_RESERVE); BUILD_BUG_ON(__GFP_KSWAPD_RECLAIM != (__force gfp_t) ALLOC_KSWAPD); /* * The caller may dip into page reserves a bit more if the caller * cannot run direct reclaim, or if the caller has realtime scheduling * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will - * set both ALLOC_HARDER (__GFP_ATOMIC) and ALLOC_HIGH (__GFP_HIGH). + * set both ALLOC_HARDER (__GFP_ATOMIC) and ALLOC_MIN_RESERVE(__GFP_HIGH). */ alloc_flags |= (__force int) (gfp_mask & (__GFP_HIGH | __GFP_KSWAPD_RECLAIM)); -- 2.35.3