[PATCH] x86_64: Make node boundaries consistent (ffd10a2b) · Commits · 戴 / test

The current x86_64 NUMA memory code is inconsequent when it comes to node memory ranges. The exact behaviour varies depending on which config option that is used. setup_node_bootmem() has start and end as arguments and these are used to calculate the size of the node like this: (end - start). This is all fine if end is pointing to the first non-available byte. The problem is that the current x86_64 code sometimes treats it as the last present byte and sometimes as the first non-available byte. The result is that some configurations might lose a page at the end of the range. This patch tries to fix CONFIG_ACPI_NUMA, CONFIG_K8_NUMA and CONFIG_NUMA_EMU so they all treat the end variable as the first non-available byte. This is the same way as the single node code. The patch is boot tested on dual x86_64 hardware with the above configurations, but maybe the removed code is needed as some workaround? Signed-off-by:

Magnus Damm <magnus@valinux.co.jp> Signed-off-by:

Andi Kleen <ak@suse.de> Signed-off-by:

Linus Torvalds <torvalds@osdl.org>

arch/x86_64/mm/k8topology.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -108,6 +108,7 @@ int __init k8_scan_nodes(unsigned long start, unsigned long end)
		limit >>= 16;
		limit <<= 24;
		limit \|= (1<<24)-1;
		limit++;

		if (limit > end_pfn << PAGE_SHIFT)
		limit = end_pfn << PAGE_SHIFT;

arch/x86_64/mm/numa.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -209,8 +209,6 @@ static int numa_emulation(unsigned long start_pfn, unsigned long end_pfn)
		if (i == numa_fake-1)
		sz = (end_pfn<<PAGE_SHIFT) - nodes[i].start;
		nodes[i].end = nodes[i].start + sz;
		if (i != numa_fake-1)
		nodes[i].end--;
		printk(KERN_INFO "Faking node %d at %016Lx-%016Lx (%LuMB)\n",
		i,
		nodes[i].start, nodes[i].end,

arch/x86_64/mm/srat.c

+0 −4

Original line number	Diff line number	Diff line
		@@ -71,8 +71,6 @@ static __init void cutoff_node(int i, unsigned long start, unsigned long end)
		nd->start = nd->end;
		}
		if (nd->end > end) {
		if (!(end & 0xfff))
		end--;
		nd->end = end;
		if (nd->start > nd->end)
		nd->start = nd->end;
		@@ -166,8 +164,6 @@ acpi_numa_memory_affinity_init(struct acpi_table_memory_affinity *ma)
		if (nd->end < end)
		nd->end = end;
		}
		if (!(nd->end & 0xfff))
		nd->end--;
		printk(KERN_INFO "SRAT: Node %u PXM %u %Lx-%Lx\n", node, pxm,
		nd->start, nd->end);
		}

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