lkml.org 
[lkml]   [2008]   [May]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] x86_32: use per_cpu data
From: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>

use per_cpu for per CPU data.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
---
arch/x86/kernel/nmi_32.c | 29 +++++++++++++++++------------
1 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/nmi_32.c b/arch/x86/kernel/nmi_32.c
index 11b14bb..69bdae5 100644
--- a/arch/x86/kernel/nmi_32.c
+++ b/arch/x86/kernel/nmi_32.c
@@ -293,9 +293,9 @@ void stop_apic_nmi_watchdog(void *unused)
* here too!]
*/

-static unsigned int
- last_irq_sums [NR_CPUS],
- alert_counter [NR_CPUS];
+static DEFINE_PER_CPU(unsigned, last_irq_sum);
+static DEFINE_PER_CPU(local_t, alert_counter);
+static DEFINE_PER_CPU(int, nmi_touch);

void touch_nmi_watchdog(void)
{
@@ -303,12 +303,13 @@ void touch_nmi_watchdog(void)
unsigned cpu;

/*
- * Just reset the alert counters, (other CPUs might be
- * spinning on locks we hold):
+ * Tell other CPUs to reset their alert counters. We cannot
+ * do it ourselves because the alert count increase is not
+ * atomic.
*/
for_each_present_cpu(cpu) {
- if (alert_counter[cpu])
- alert_counter[cpu] = 0;
+ if (per_cpu(nmi_touch, cpu) != 1)
+ per_cpu(nmi_touch, cpu) = 1;
}
}

@@ -358,22 +359,26 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
*/
sum = per_cpu(irq_stat, cpu).apic_timer_irqs +
per_cpu(irq_stat, cpu).irq0_irqs;
+ if (__get_cpu_var(nmi_touch)) {
+ __get_cpu_var(nmi_touch) = 0;
+ touched = 1;
+ }

/* if the none of the timers isn't firing, this cpu isn't doing much */
- if (!touched && last_irq_sums[cpu] == sum) {
+ if (!touched && __get_cpu_var(last_irq_sum) == sum) {
/*
* Ayiee, looks like this CPU is stuck ...
* wait a few IRQs (5 seconds) before doing the oops ...
*/
- alert_counter[cpu]++;
- if (alert_counter[cpu] == 5*nmi_hz)
+ local_inc(&__get_cpu_var(alert_counter));
+ if (local_read(&__get_cpu_var(alert_counter)) == 5*nmi_hz)
/*
* die_nmi will return ONLY if NOTIFY_STOP happens..
*/
die_nmi(regs, "BUG: NMI Watchdog detected LOCKUP");
} else {
- last_irq_sums[cpu] = sum;
- alert_counter[cpu] = 0;
+ __get_cpu_var(last_irq_sum) = sum;
+ local_set(&__get_cpu_var(alert_counter), 0);
}
/* see if the nmi watchdog went off */
if (!__get_cpu_var(wd_enabled))
--
1.5.4.1


\
 
 \ /
  Last update: 2008-05-03 01:47    [W:0.074 / U:5.572 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site