From b377fd3982ad957c796758a90e2988401a884241 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Wed, 22 Aug 2007 14:02:05 -0700 Subject: Apply memory policies to top two highest zones when highest zone is ZONE_MOVABLE The NUMA layer only supports NUMA policies for the highest zone. When ZONE_MOVABLE is configured with kernelcore=, the the highest zone becomes ZONE_MOVABLE. The result is that policies are only applied to allocations like anonymous pages and page cache allocated from ZONE_MOVABLE when the zone is used. This patch applies policies to the two highest zones when the highest zone is ZONE_MOVABLE. As ZONE_MOVABLE consists of pages from the highest "real" zone, it's always functionally equivalent. The patch has been tested on a variety of machines both NUMA and non-NUMA covering x86, x86_64 and ppc64. No abnormal results were seen in kernbench, tbench, dbench or hackbench. It passes regression tests from the numactl package with and without kernelcore= once numactl tests are patched to wait for vmstat counters to update. akpm: this is the nasty hack to fix NUMA mempolicies in the presence of ZONE_MOVABLE and kernelcore= in 2.6.23. Christoph says "For .24 either merge the mobility or get the other solution that Mel is working on. That solution would only use a single zonelist per node and filter on the fly. That may help performance and also help to make memory policies work better." Signed-off-by: Mel Gorman Acked-by: Lee Schermerhorn Tested-by: Lee Schermerhorn Acked-by: Christoph Lameter Cc: Andi Kleen Cc: Paul Mundt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mempolicy.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/mempolicy.c') diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 71b84b45154a..172abffeb2e3 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -149,7 +149,7 @@ static struct zonelist *bind_zonelist(nodemask_t *nodes) lower zones etc. Avoid empty zones because the memory allocator doesn't like them. If you implement node hot removal you have to fix that. */ - k = policy_zone; + k = MAX_NR_ZONES - 1; while (1) { for_each_node_mask(nd, *nodes) { struct zone *z = &NODE_DATA(nd)->node_zones[k]; -- cgit v1.2.3-70-g09d2