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authorDavid S. Miller <davem@davemloft.net>2011-02-19 19:17:35 -0800
committerDavid S. Miller <davem@davemloft.net>2011-02-19 19:17:35 -0800
commitda935c66bacb3ed9ada984b053297f87c2dff63a (patch)
tree46278da2b312c73f1375b830d7e5912bf23abd78 /kernel/watchdog.c
parent9435eb1cf0b76b323019cebf8d16762a50a12a19 (diff)
parent2205a6ea93fea76f88b43727fea53f3ce3790d6f (diff)
downloadlinux-linaro-stable-da935c66bacb3ed9ada984b053297f87c2dff63a.tar.gz
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts: Documentation/feature-removal-schedule.txt drivers/net/e1000e/netdev.c net/xfrm/xfrm_policy.c
Diffstat (limited to 'kernel/watchdog.c')
-rw-r--r--kernel/watchdog.c53
1 files changed, 27 insertions, 26 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index d7ebdf4cea98..18bb15776c57 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -27,7 +27,7 @@
#include <asm/irq_regs.h>
#include <linux/perf_event.h>
-int watchdog_enabled;
+int watchdog_enabled = 1;
int __read_mostly softlockup_thresh = 60;
static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts);
@@ -43,9 +43,6 @@ static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts_saved);
static DEFINE_PER_CPU(struct perf_event *, watchdog_ev);
#endif
-static int no_watchdog;
-
-
/* boot commands */
/*
* Should we panic when a soft-lockup or hard-lockup occurs:
@@ -58,7 +55,7 @@ static int __init hardlockup_panic_setup(char *str)
if (!strncmp(str, "panic", 5))
hardlockup_panic = 1;
else if (!strncmp(str, "0", 1))
- no_watchdog = 1;
+ watchdog_enabled = 0;
return 1;
}
__setup("nmi_watchdog=", hardlockup_panic_setup);
@@ -77,7 +74,7 @@ __setup("softlockup_panic=", softlockup_panic_setup);
static int __init nowatchdog_setup(char *str)
{
- no_watchdog = 1;
+ watchdog_enabled = 0;
return 1;
}
__setup("nowatchdog", nowatchdog_setup);
@@ -85,7 +82,7 @@ __setup("nowatchdog", nowatchdog_setup);
/* deprecated */
static int __init nosoftlockup_setup(char *str)
{
- no_watchdog = 1;
+ watchdog_enabled = 0;
return 1;
}
__setup("nosoftlockup", nosoftlockup_setup);
@@ -366,8 +363,14 @@ static int watchdog_nmi_enable(int cpu)
goto out_save;
}
- printk(KERN_ERR "NMI watchdog disabled for cpu%i: unable to create perf event: %ld\n",
- cpu, PTR_ERR(event));
+
+ /* vary the KERN level based on the returned errno */
+ if (PTR_ERR(event) == -EOPNOTSUPP)
+ printk(KERN_INFO "NMI watchdog disabled (cpu%i): not supported (no LAPIC?)\n", cpu);
+ else if (PTR_ERR(event) == -ENOENT)
+ printk(KERN_WARNING "NMI watchdog disabled (cpu%i): hardware events not enabled\n", cpu);
+ else
+ printk(KERN_ERR "NMI watchdog disabled (cpu%i): unable to create perf event: %ld\n", cpu, PTR_ERR(event));
return PTR_ERR(event);
/* success path */
@@ -432,9 +435,6 @@ static int watchdog_enable(int cpu)
wake_up_process(p);
}
- /* if any cpu succeeds, watchdog is considered enabled for the system */
- watchdog_enabled = 1;
-
return 0;
}
@@ -462,12 +462,16 @@ static void watchdog_disable(int cpu)
static void watchdog_enable_all_cpus(void)
{
int cpu;
- int result = 0;
+
+ watchdog_enabled = 0;
for_each_online_cpu(cpu)
- result += watchdog_enable(cpu);
+ if (!watchdog_enable(cpu))
+ /* if any cpu succeeds, watchdog is considered
+ enabled for the system */
+ watchdog_enabled = 1;
- if (result)
+ if (!watchdog_enabled)
printk(KERN_ERR "watchdog: failed to be enabled on some cpus\n");
}
@@ -476,9 +480,6 @@ static void watchdog_disable_all_cpus(void)
{
int cpu;
- if (no_watchdog)
- return;
-
for_each_online_cpu(cpu)
watchdog_disable(cpu);
@@ -498,10 +499,12 @@ int proc_dowatchdog_enabled(struct ctl_table *table, int write,
{
proc_dointvec(table, write, buffer, length, ppos);
- if (watchdog_enabled)
- watchdog_enable_all_cpus();
- else
- watchdog_disable_all_cpus();
+ if (write) {
+ if (watchdog_enabled)
+ watchdog_enable_all_cpus();
+ else
+ watchdog_disable_all_cpus();
+ }
return 0;
}
@@ -530,7 +533,8 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
break;
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
- err = watchdog_enable(hotcpu);
+ if (watchdog_enabled)
+ err = watchdog_enable(hotcpu);
break;
#ifdef CONFIG_HOTPLUG_CPU
case CPU_UP_CANCELED:
@@ -555,9 +559,6 @@ void __init lockup_detector_init(void)
void *cpu = (void *)(long)smp_processor_id();
int err;
- if (no_watchdog)
- return;
-
err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
WARN_ON(notifier_to_errno(err));