diff options
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 93baebcc06f3..2cb9eb71e282 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -97,6 +97,14 @@ EXPORT_SYMBOL(node_states); unsigned long totalram_pages __read_mostly; unsigned long totalreserve_pages __read_mostly; +/* + * When calculating the number of globally allowed dirty pages, there + * is a certain number of per-zone reserves that should not be + * considered dirtyable memory. This is the sum of those reserves + * over all existing zones that contribute dirtyable memory. + */ +unsigned long dirty_balance_reserve __read_mostly; + int percpu_pagelist_fraction; gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK; @@ -4822,8 +4830,19 @@ static void calculate_totalreserve_pages(void) if (max > zone->present_pages) max = zone->present_pages; reserve_pages += max; + /* + * Lowmem reserves are not available to + * GFP_HIGHUSER page cache allocations and + * kswapd tries to balance zones to their high + * watermark. As a result, neither should be + * regarded as dirtyable memory, to prevent a + * situation where reclaim has to clean pages + * in order to balance the zones. + */ + zone->dirty_balance_reserve = max; } } + dirty_balance_reserve = reserve_pages; totalreserve_pages = reserve_pages; } |