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37 lines
1.3 KiB
37 lines
1.3 KiB
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Subject: [PATCH 09/31] mm: system wide ALLOC_NO_WATERMARK
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Patch-mainline: not yet
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The reserve is proportionally distributed over all (!highmem) zones in the
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system. So we need to allow an emergency allocation access to all zones. In
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order to do that we need to break out of any mempolicy boundaries we might
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have.
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In my opinion that does not break mempolicies as those are user oriented
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and not system oriented. That is, system allocations are not guaranteed to be
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within mempolicy boundaries. For instance IRQs don't even have a mempolicy.
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So breaking out of mempolicy boundaries for 'rare' emergency allocations,
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which are always system allocations (as opposed to user) is ok.
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Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
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---
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mm/page_alloc.c | 5 +++++
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1 file changed, 5 insertions(+)
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--- a/mm/page_alloc.c
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+++ b/mm/page_alloc.c
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@@ -1995,6 +1995,11 @@ restart:
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rebalance:
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/* Allocate without watermarks if the context allows */
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if (alloc_flags & ALLOC_NO_WATERMARKS) {
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+ /*
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+ * break out mempolicy boundaries
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+ */
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+ zonelist = node_zonelist(numa_node_id(), gfp_mask);
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+
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page = __alloc_pages_high_priority(gfp_mask, order,
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zonelist, high_zoneidx, nodemask,
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preferred_zone, migratetype);
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