diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 486587fcd27f4..de313f1c15f99 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -674,12 +674,22 @@ enum zone_watermarks { #define high_wmark_pages(z) (z->_watermark[WMARK_HIGH] + z->watermark_boost) #define wmark_pages(z, i) (z->_watermark[i] + z->watermark_boost) +/* + * Flags used in pcp->flags field. + * + * PCPF_PREV_FREE_HIGH_ORDER: a high-order page is freed in the + * previous page freeing. To avoid to drain PCP for an accident + * high-order page freeing. + */ +#define PCPF_PREV_FREE_HIGH_ORDER BIT(0) + struct per_cpu_pages { spinlock_t lock; /* Protects lists field */ int count; /* number of pages in the list */ int high; /* high watermark, emptying needed */ int batch; /* chunk size for buddy add/remove */ - short free_factor; /* batch scaling factor during free */ + u8 flags; /* protected by pcp->lock */ + u8 free_factor; /* batch scaling factor during free */ #ifdef CONFIG_NUMA short expire; /* When 0, remote pagesets are drained */ #endif diff --git a/mm/page_alloc.c b/mm/page_alloc.c index f46e519618a07..de547ef9a9adc 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2370,7 +2370,7 @@ static void free_unref_page_commit(struct zone *zone, struct per_cpu_pages *pcp, { int high; int pindex; - bool free_high; + bool free_high = false; __count_vm_events(PGFREE, 1 << order); pindex = order_to_pindex(migratetype, order); @@ -2383,8 +2383,13 @@ static void free_unref_page_commit(struct zone *zone, struct per_cpu_pages *pcp, * freeing without allocation. The remainder after bulk freeing * stops will be drained from vmstat refresh context. */ - free_high = (pcp->free_factor && order && order <= PAGE_ALLOC_COSTLY_ORDER); - + if (order && order <= PAGE_ALLOC_COSTLY_ORDER) { + free_high = (pcp->free_factor && + (pcp->flags & PCPF_PREV_FREE_HIGH_ORDER)); + pcp->flags |= PCPF_PREV_FREE_HIGH_ORDER; + } else if (pcp->flags & PCPF_PREV_FREE_HIGH_ORDER) { + pcp->flags &= ~PCPF_PREV_FREE_HIGH_ORDER; + } high = nr_pcp_high(pcp, zone, free_high); if (pcp->count >= high) { free_pcppages_bulk(zone, nr_pcp_free(pcp, high, free_high), pcp, pindex);