Re: [PATCH] Fake NUMA emulation for PowerPC (Take 2)
From: Balbir Singh <hidden>
Date: 2008-01-26 07:13:54
Also in:
lkml
* Michael Ellerman [off-list ref] [2008-01-18 16:44:58]:
quoted hunk ↗ jump to hunk
This fixes it, although I'm a little worried about some of the removals/movings of node_set_online() in the patch.diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 1666e7d..dcedc26 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c@@ -49,7 +49,6 @@ static int __cpuinit fake_numa_create_new_node(unsigned long end_pfn, static unsigned int fake_nid = 0; static unsigned long long curr_boundary = 0; - *nid = fake_nid; if (!p) return 0;@@ -60,6 +59,7 @@ static int __cpuinit fake_numa_create_new_node(unsigned long end_pfn, if (mem < curr_boundary) return 0; + *nid = fake_nid; curr_boundary = mem; if ((end_pfn << PAGE_SHIFT) > mem) {
Hi, Michael, Here's a better and more complete fix for the problem. Could you please see if it works for you? I tested it on a real NUMA box and it seemed to work fine there. Description ----------- This patch provides a fix for the problem found by Michael Ellerman [off-list ref] while using fake NUMA nodes on a cell box. The code modifies node id iff (as in if and only if) fake NUMA nodes are created. Signed-off-by: Balbir Singh <redacted> --- arch/powerpc/mm/numa.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff -puN arch/powerpc/mm/numa.c~fix-fake-numa-nid-on-numa arch/powerpc/mm/numa.c
--- linux-2.6.24-rc8/arch/powerpc/mm/numa.c~fix-fake-numa-nid-on-numa 2008-01-26 12:20:29.000000000 +0530
+++ linux-2.6.24-rc8-balbir/arch/powerpc/mm/numa.c 2008-01-26 12:27:53.000000000 +0530@@ -49,7 +49,12 @@ static int __cpuinit fake_numa_create_ne static unsigned int fake_nid = 0; static unsigned long long curr_boundary = 0; - *nid = fake_nid; + /* + * If we did enable fake nodes and cross a node, + * remember the last node and start from there. + */ + if (fake_nid) + *nid = fake_nid; if (!p) return 0;
_ -- Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL