From f2890255b0ade497893d1e5e99f519b5c1d50f7d Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Tue, 17 Jul 2007 04:03:57 -0700 Subject: [PATCH] i386: speedup touch_nmi_watchdog Avoid dirtying remote cpu's memory if it already has the correct value. Cc: Andi Kleen Cc: Konrad Rzeszutek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/nmi.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index fba121f7973..03b7f5584d7 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -295,7 +295,7 @@ static unsigned int last_irq_sums [NR_CPUS], alert_counter [NR_CPUS]; -void touch_nmi_watchdog (void) +void touch_nmi_watchdog(void) { if (nmi_watchdog > 0) { unsigned cpu; @@ -304,8 +304,10 @@ void touch_nmi_watchdog (void) * Just reset the alert counters, (other CPUs might be * spinning on locks we hold): */ - for_each_present_cpu (cpu) - alert_counter[cpu] = 0; + for_each_present_cpu(cpu) { + if (alert_counter[cpu]) + alert_counter[cpu] = 0; + } } /* -- 2.41.1