From: Keshavamurthy, Anil S <anil.s.keshavamurthy@intel.com>
Date: Wed, 2 May 2007 17:27:18 +0000 (+0200)
Subject: [PATCH] i386: avoid checking for cpu gone when CONFIG_HOTPLUG_CPU not defined
X-Git-Tag: v2.6.22-rc1~1011^2~45
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e8a72ffa3aa618fb25b5727c0e0ae939d30d66c0;p=linux-2.6

[PATCH] i386: avoid checking for cpu gone when CONFIG_HOTPLUG_CPU not defined

Avoid checking for cpu gone in mm hot path when CONFIG_HOTPLUG_CPU is not
defined.

Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/arch/i386/kernel/smp.c b/arch/i386/kernel/smp.c
index f8667109db..f98c3ffd6f 100644
--- a/arch/i386/kernel/smp.c
+++ b/arch/i386/kernel/smp.c
@@ -359,10 +359,12 @@ void native_flush_tlb_others(const cpumask_t *cpumaskp, struct mm_struct *mm,
 	BUG_ON(cpu_isset(smp_processor_id(), cpumask));
 	BUG_ON(!mm);
 
+#ifdef CONFIG_HOTPLUG_CPU
 	/* If a CPU which we ran on has gone down, OK. */
 	cpus_and(cpumask, cpumask, cpu_online_map);
-	if (cpus_empty(cpumask))
+	if (unlikely(cpus_empty(cpumask)))
 		return;
+#endif
 
 	/*
 	 * i'm not happy about this global shared spinlock in the