From 8446f1d391f3d27e6bf9c43d4cbcdac0ca720417 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 6 Sep 2005 15:16:27 -0700 Subject: [PATCH] detect soft lockups This patch adds a new kernel debug feature: CONFIG_DETECT_SOFTLOCKUP. When enabled then per-CPU watchdog threads are started, which try to run once per second. If they get delayed for more than 10 seconds then a callback from the timer interrupt detects this condition and prints out a warning message and a stack dump (once per lockup incident). The feature is otherwise non-intrusive, it doesnt try to unlock the box in any way, it only gets the debug info out, automatically, and on all CPUs affected by the lockup. Signed-off-by: Ingo Molnar Signed-off-by: Nishanth Aravamudan Signed-Off-By: Matthias Urlichs Signed-off-by: Richard Purdie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/nmi.c | 5 +++++ arch/i386/kernel/time.c | 1 + arch/x86_64/kernel/nmi.c | 2 ++ arch/x86_64/kernel/time.c | 1 + 4 files changed, 9 insertions(+) (limited to 'arch') diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index 8bbdbda07a2..0178457db72 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -478,6 +478,11 @@ void touch_nmi_watchdog (void) */ for (i = 0; i < NR_CPUS; i++) alert_counter[i] = 0; + + /* + * Tickle the softlockup detector too: + */ + touch_softlockup_watchdog(); } extern void die_nmi(struct pt_regs *, const char *msg); diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c index 6f794a78ee1..b0c5ee2b344 100644 --- a/arch/i386/kernel/time.c +++ b/arch/i386/kernel/time.c @@ -422,6 +422,7 @@ static int timer_resume(struct sys_device *dev) last_timer->resume(); cur_timer = last_timer; last_timer = NULL; + touch_softlockup_watchdog(); return 0; } diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c index 64a8e05d581..84cae81fff8 100644 --- a/arch/x86_64/kernel/nmi.c +++ b/arch/x86_64/kernel/nmi.c @@ -463,6 +463,8 @@ void touch_nmi_watchdog (void) */ for (i = 0; i < NR_CPUS; i++) per_cpu(nmi_touch, i) = 1; + + touch_softlockup_watchdog(); } void nmi_watchdog_tick (struct pt_regs * regs, unsigned reason) diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c index 66bf6ddeb0c..2b5d9da912a 100644 --- a/arch/x86_64/kernel/time.c +++ b/arch/x86_64/kernel/time.c @@ -1041,6 +1041,7 @@ static int timer_resume(struct sys_device *dev) write_sequnlock_irqrestore(&xtime_lock,flags); jiffies += sleep_length; wall_jiffies += sleep_length; + touch_softlockup_watchdog(); return 0; } -- cgit v1.2.3-70-g09d2