From c118baf802562688d46e6002f2b5fe66b947da21 Mon Sep 17 00:00:00 2001 From: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Date: Thu, 5 Nov 2015 18:46:29 -0800 Subject: [PATCH] arch/powerpc/mm/numa.c: do not allocate bootmem memory for non existing nodes With the setup_nr_nodes(), we have already initialized node_possible_map. So it is safe to use for_each_node here. There are many places in the kernel that use hardcoded 'for' loop with nr_node_ids, because all other architectures have numa nodes populated serially. That should be reason we had maintained the same for powerpc. But, since sparse numa node ids possible on powerpc, we unnecessarily allocate memory for non existent numa nodes. For e.g., on a system with 0,1,16,17 as numa nodes nr_node_ids=18 and we allocate memory for nodes 2-14. This patch we allocate memory for only existing numa nodes. The patch is boot tested on a 4 node tuleta, confirming with printks that it works as expected. Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Anton Blanchard <anton@samba.org> Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Cc: Greg Kurz <gkurz@linux.vnet.ibm.com> Cc: Grant Likely <grant.likely@linaro.org> Cc: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- arch/powerpc/mm/numa.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 8b9502adaf79..8d8a541211d0 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -80,7 +80,7 @@ static void __init setup_node_to_cpumask_map(void) setup_nr_node_ids(); /* allocate the map */ - for (node = 0; node < nr_node_ids; node++) + for_each_node(node) alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]); /* cpumask_of_node() will now work */ -- 2.34.1