From 53516d4abacfab1faaa075c1f79957abc3da358c Mon Sep 17 00:00:00 2001
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Date: Mon, 21 Sep 2020 15:26:47 +0530
Subject: [PATCH] powerpc/smp: Limit CPUs traversed to within a node.
References: jsc#SLE-13615 bsc#1180100 ltc#190257
Patch-mainline: v5.10-rc1
Git-commit: 53516d4abacfab1faaa075c1f79957abc3da358c
All the arch specific topology cpumasks are within a node/DIE.
However when setting these per CPU cpumasks, system traverses through
all the online CPUs. This is redundant.
Reduce the traversal to only CPUs that are online in the node to which
the CPU belongs to.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200921095653.9701-6-srikar@linux.vnet.ibm.com
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/kernel/smp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 9cdb966f00b3..9455af47123c 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -1241,7 +1241,7 @@ static bool update_mask_by_l2(int cpu, struct cpumask *(*mask_fn)(int))
}
cpumask_set_cpu(cpu, mask_fn(cpu));
- for_each_cpu(i, cpu_online_mask) {
+ for_each_cpu_and(i, cpu_online_mask, cpu_cpu_mask(cpu)) {
/*
* when updating the marks the current CPU has not been marked
* online, but we need to update the cache masks
--
2.26.2