diff options
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 44 |
1 files changed, 24 insertions, 20 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index ffe2151d11ee..18ca33a1945d 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4007,18 +4007,19 @@ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, * __GFP_HIGH allows access to 50% of the min reserve as well * as OOM. */ - if (alloc_flags & ALLOC_MIN_RESERVE) + if (alloc_flags & ALLOC_MIN_RESERVE) { min -= min / 2; - /* - * Non-blocking allocations can access some of the reserve - * with more access if also __GFP_HIGH. The reasoning is that - * a non-blocking caller may incur a more severe penalty - * if it cannot get memory quickly, particularly if it's - * also __GFP_HIGH. - */ - if (alloc_flags & ALLOC_HARDER) - min -= min / 4; + /* + * Non-blocking allocations (e.g. GFP_ATOMIC) can + * access more reserves than just __GFP_HIGH. Other + * non-blocking allocations requests such as GFP_NOWAIT + * or (GFP_KERNEL & ~__GFP_DIRECT_RECLAIM) do not get + * access to the min reserve. + */ + if (alloc_flags & ALLOC_NON_BLOCK) + min -= min / 4; + } /* * OOM victims can try even harder than the normal reserve @@ -4869,28 +4870,30 @@ gfp_to_alloc_flags(gfp_t gfp_mask, unsigned int order) * 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_MIN_RESERVE(__GFP_HIGH). + * set both ALLOC_NON_BLOCK and ALLOC_MIN_RESERVE(__GFP_HIGH). */ alloc_flags |= (__force int) (gfp_mask & (__GFP_HIGH | __GFP_KSWAPD_RECLAIM)); - if (gfp_mask & __GFP_ATOMIC) { + if (!(gfp_mask & __GFP_DIRECT_RECLAIM)) { /* * Not worth trying to allocate harder for __GFP_NOMEMALLOC even * if it can't schedule. */ if (!(gfp_mask & __GFP_NOMEMALLOC)) { - alloc_flags |= ALLOC_HARDER; + alloc_flags |= ALLOC_NON_BLOCK; if (order > 0) alloc_flags |= ALLOC_HIGHATOMIC; } /* - * Ignore cpuset mems for GFP_ATOMIC rather than fail, see the - * comment for __cpuset_node_allowed(). + * Ignore cpuset mems for non-blocking __GFP_HIGH (probably + * GFP_ATOMIC) rather than fail, see the comment for + * __cpuset_node_allowed(). */ - alloc_flags &= ~ALLOC_CPUSET; + if (alloc_flags & ALLOC_MIN_RESERVE) + alloc_flags &= ~ALLOC_CPUSET; } else if (unlikely(rt_task(current)) && in_task()) alloc_flags |= ALLOC_MIN_RESERVE; @@ -5321,12 +5324,13 @@ nopage: WARN_ON_ONCE_GFP(costly_order, gfp_mask); /* - * Help non-failing allocations by giving them access to memory - * reserves but do not use ALLOC_NO_WATERMARKS because this + * Help non-failing allocations by giving some access to memory + * reserves normally used for high priority non-blocking + * allocations but do not use ALLOC_NO_WATERMARKS because this * could deplete whole memory reserves which would just make - * the situation worse + * the situation worse. */ - page = __alloc_pages_cpuset_fallback(gfp_mask, order, ALLOC_HARDER, ac); + page = __alloc_pages_cpuset_fallback(gfp_mask, order, ALLOC_MIN_RESERVE, ac); if (page) goto got_pg; |