From 81d50bb254ed53a0da45a65988e4e1fa08e8a541 Mon Sep 17 00:00:00 2001 From: Hiroshi Shimamoto Date: Thu, 15 May 2008 19:42:49 -0700 Subject: [PATCH 1/8] posix-timers: print RT watchdog message It's useful to detect which process is killed by RT watchdog. Signed-off-by: Hiroshi Shimamoto Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- kernel/posix-cpu-timers.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index f1525ad06cb3..c42a03aef36f 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -1037,6 +1037,9 @@ static void check_thread_timers(struct task_struct *tsk, sig->rlim[RLIMIT_RTTIME].rlim_cur += USEC_PER_SEC; } + printk(KERN_INFO + "RT Watchdog Timeout: %s[%d]\n", + tsk->comm, task_pid_nr(tsk)); __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); } } From d031476408ae0f5196e3c579f519dfdefb099b67 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 23 May 2008 14:41:19 +0100 Subject: [PATCH 2/8] hrtimer: remove warning in hres_timers_resume hres_timers_resume() warns if there appears to be more than one cpu online. This warning makes sense when the suspend/resume mechanism offlines all cpus but one during the suspend/resume process. However, Xen suspend does not need to offline the other cpus; it merely keeps them tied up in stop_machine() while the virtual machine is suspended. The warning hres_timers_resume issues is therefore spurious. Signed-off-by: Jeremy Fitzhardinge Cc: xen-devel Cc: "Rafael J. Wysocki" Signed-off-by: Thomas Gleixner --- kernel/hrtimer.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 421be5fe5cc7..493c4b8b8cba 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -632,8 +632,6 @@ void clock_was_set(void) */ void hres_timers_resume(void) { - WARN_ON_ONCE(num_online_cpus() > 1); - /* Retrigger the CPU local events: */ retrigger_next_event(NULL); } From 900cfa46191a7d87cf1891924cb90499287fd235 Mon Sep 17 00:00:00 2001 From: "Carlos R. Mafra" Date: Thu, 22 May 2008 19:25:11 -0300 Subject: [PATCH 3/8] hrtimer: Remove unused variables in ktime_divns() The variables dns and inc are not used, remove them. Signed-off-by: Carlos R. Mafra Cc: tglx@linutronix.de Signed-off-by: Thomas Gleixner --- kernel/hrtimer.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 493c4b8b8cba..635739d219da 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -300,11 +300,10 @@ EXPORT_SYMBOL_GPL(ktime_sub_ns); */ u64 ktime_divns(const ktime_t kt, s64 div) { - u64 dclc, inc, dns; + u64 dclc; int sft = 0; - dclc = dns = ktime_to_ns(kt); - inc = div; + dclc = ktime_to_ns(kt); /* Make sure the divisor is less than 2^32: */ while (div >> 32) { sft++; From 7a14ce1d8c1d3a6118d406e64eaf9aa70375e085 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 12 May 2008 15:43:53 +0200 Subject: [PATCH 4/8] nohz: reduce jiffies polling overhead Signed-off-by: Ingo Molnar --- kernel/time/tick-sched.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index b854a895591e..cb75394ed00e 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -48,6 +48,13 @@ static void tick_do_update_jiffies64(ktime_t now) unsigned long ticks = 0; ktime_t delta; + /* + * Do a quick check without holding xtime_lock: + */ + delta = ktime_sub(now, last_jiffies_update); + if (delta.tv64 < tick_period.tv64) + return; + /* Reevalute with xtime_lock held */ write_seqlock(&xtime_lock); From 6b148507d3d042a3c11f4c3f6c0f649c6a89220d Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 21 May 2008 21:14:58 +0200 Subject: [PATCH 5/8] pmtmr: allow command line override of ioport Stupid BIOSes do not tell us about the PMTimer, but we might know where it is. Signed-off-by: Thomas Gleixner --- drivers/clocksource/acpi_pm.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c index 7b46faf22318..3baee020afc2 100644 --- a/drivers/clocksource/acpi_pm.c +++ b/drivers/clocksource/acpi_pm.c @@ -215,3 +215,22 @@ static int __init init_acpi_pm_clocksource(void) * but we still need to load before device_initcall */ fs_initcall(init_acpi_pm_clocksource); + +/* + * Allow an override of the IOPort. Stupid BIOSes do not tell us about + * the PMTimer, but we might know where it is. + */ +static int __init parse_pmtmr(char *arg) +{ + unsigned long base; + + if (strict_strtoul(arg, 16, &base)) + return -EINVAL; + + printk(KERN_INFO "PMTMR IOPort override: 0x%04lx -> 0x%04lx\n", + pmtmr_ioport, base); + pmtmr_ioport = base; + + return 1; +} +__setup("pmtmr=", parse_pmtmr); From 857f3fd7a496ddf4329345af65a4a2b16dd25fe8 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Fri, 11 Jul 2008 11:09:22 +0200 Subject: [PATCH 6/8] nohz: don't stop idle tick if softirqs are pending. In case a cpu goes idle but softirqs are pending only an error message is printed to the console. It may take a very long time until the pending softirqs will finally be executed. Worst case would be a hanging system. With this patch the timer tick just continues and the softirqs will be executed after the next interrupt. Still a delay but better than a hanging system. Currently we have at least two device drivers on s390 which under certain circumstances schedule a tasklet from process context. This is a reason why we can end up with pending softirqs when going idle. Fixing these drivers seems to be non-trivial. However there is no question that the drivers should be fixed. This patch shouldn't be considered as a bug fix. It just is intended to keep a system running even if device drivers are buggy. Signed-off-by: Heiko Carstens Cc: Jan Glauber Cc: Stefan Weinhuber Cc: Andrew Morton Signed-off-by: Ingo Molnar --- kernel/time/tick-sched.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index cb75394ed00e..86baa4f0dfe4 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -235,6 +235,7 @@ void tick_nohz_stop_sched_tick(void) local_softirq_pending()); ratelimit++; } + goto end; } ts->idle_calls++; From 38032f72601deac7aab00691c79e83d09b204e2a Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Fri, 11 Jul 2008 12:57:31 -0700 Subject: [PATCH 7/8] acpi_pm clccksource: fix printk format warning Fix printk format warning in acpi_pm clocksource: linux-next-20080711/drivers/clocksource/acpi_pm.c:231: warning: format '%04lx' expects type 'long unsigned int', but argument 2 has type 'u32' Signed-off-by: Randy Dunlap Cc: akpm Signed-off-by: Thomas Gleixner --- drivers/clocksource/acpi_pm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c index 3baee020afc2..bcd7d0e429e8 100644 --- a/drivers/clocksource/acpi_pm.c +++ b/drivers/clocksource/acpi_pm.c @@ -227,8 +227,8 @@ static int __init parse_pmtmr(char *arg) if (strict_strtoul(arg, 16, &base)) return -EINVAL; - printk(KERN_INFO "PMTMR IOPort override: 0x%04lx -> 0x%04lx\n", - pmtmr_ioport, base); + printk(KERN_INFO "PMTMR IOPort override: 0x%04x -> 0x%04x\n", + (unsigned int)pmtmr_ioport, base); pmtmr_ioport = base; return 1; From de32a2434f7ce4600da90ecb44abcdc365ada1d0 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sat, 12 Jul 2008 05:33:30 +0200 Subject: [PATCH 8/8] kernel-paramaters: document pmtmr= command line option Signed-off-by: Thomas Gleixner --- Documentation/kernel-parameters.txt | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index e07c432c731f..356b64ba706a 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1571,6 +1571,10 @@ and is between 256 and 4096 characters. It is defined in the file Format: { parport | timid | 0 } See also Documentation/parport.txt. + pmtmr= [X86] Manual setup of pmtmr I/O Port. + Override pmtimer IOPort with a hex value. + e.g. pmtmr=0x508 + pnpacpi= [ACPI] { off }