diff options
| -rw-r--r-- | mm/page_alloc.c | 94 |
1 files changed, 50 insertions, 44 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d3be076ea9c5..ef870fb92f74 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1574,15 +1574,6 @@ __alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order, return page; } -static inline int -is_allocation_high_priority(struct task_struct *p, gfp_t gfp_mask) -{ - if (((p->flags & PF_MEMALLOC) || unlikely(test_thread_flag(TIF_MEMDIE))) - && !in_interrupt()) - return 1; - return 0; -} - /* * This is called in the allocator slow-path if the allocation request is of * sufficient urgency to ignore watermarks and take other desperate measures @@ -1618,6 +1609,42 @@ void wake_all_kswapd(unsigned int order, struct zonelist *zonelist, wakeup_kswapd(zone, order); } +static inline int +gfp_to_alloc_flags(gfp_t gfp_mask) +{ + struct task_struct *p = current; + int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET; + const gfp_t wait = gfp_mask & __GFP_WAIT; + + /* + * 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 (!wait) and ALLOC_HIGH (__GFP_HIGH). + */ + if (gfp_mask & __GFP_HIGH) + alloc_flags |= ALLOC_HIGH; + + if (!wait) { + alloc_flags |= ALLOC_HARDER; + /* + * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc. + * See also cpuset_zone_allowed() comment in kernel/cpuset.c. + */ + alloc_flags &= ~ALLOC_CPUSET; + } else if (unlikely(rt_task(p))) + alloc_flags |= ALLOC_HARDER; + + if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) { + if (!in_interrupt() && + ((p->flags & PF_MEMALLOC) || + unlikely(test_thread_flag(TIF_MEMDIE)))) + alloc_flags |= ALLOC_NO_WATERMARKS; + } + + return alloc_flags; +} + static inline struct page * __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist, enum zone_type high_zoneidx, @@ -1648,56 +1675,35 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, * OK, we're below the kswapd watermark and have kicked background * reclaim. Now things get more complex, so set up alloc_flags according * to how we want to proceed. - * - * 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 (!wait) and ALLOC_HIGH (__GFP_HIGH). */ - alloc_flags = ALLOC_WMARK_MIN; - if ((unlikely(rt_task(p)) && !in_interrupt()) || !wait) - alloc_flags |= ALLOC_HARDER; - if (gfp_mask & __GFP_HIGH) - alloc_flags |= ALLOC_HIGH; - if (wait) - alloc_flags |= ALLOC_CPUSET; + alloc_flags = gfp_to_alloc_flags(gfp_mask); restart: - /* - * Go through the zonelist again. Let __GFP_HIGH and allocations - * coming from realtime tasks go deeper into reserves. - * - * This is the last chance, in general, before the goto nopage. - * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc. - * See also cpuset_zone_allowed() comment in kernel/cpuset.c. - */ + /* This is the last chance, in general, before the goto nopage. */ page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, - high_zoneidx, alloc_flags, - preferred_zone, - migratetype); + high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS, + preferred_zone, migratetype); if (page) goto got_pg; rebalance: /* Allocate without watermarks if the context allows */ - if (is_allocation_high_priority(p, gfp_mask)) { - /* Do not dip into emergency reserves if specified */ - if (!(gfp_mask & __GFP_NOMEMALLOC)) { - page = __alloc_pages_high_priority(gfp_mask, order, - zonelist, high_zoneidx, nodemask, preferred_zone, - migratetype); - if (page) - goto got_pg; - } - - /* Ensure no recursion into the allocator */ - goto nopage; + if (alloc_flags & ALLOC_NO_WATERMARKS) { + page = __alloc_pages_high_priority(gfp_mask, order, + zonelist, high_zoneidx, nodemask, + preferred_zone, migratetype); + if (page) + goto got_pg; } /* Atomic allocations - we can't balance anything */ if (!wait) goto nopage; + /* Avoid recursion of direct reclaim */ + if (p->flags & PF_MEMALLOC) + goto nopage; + /* Try direct reclaim and then allocating */ page = __alloc_pages_direct_reclaim(gfp_mask, order, zonelist, high_zoneidx, |