From e4fa4c97016037620f9dc8bafe03e1086b665b4c Mon Sep 17 00:00:00 2001 From: Lai Jiangshan <laijs@cn.fujitsu.com> Date: Wed, 14 Jan 2009 14:58:15 +0800 Subject: rcu: add __cpuinit to rcu_init_percpu_data() Impact: reduce memory footprint add __cpuinit to rcu_init_percpu_data(), and this function's text will be discarded after boot when !CONFIG_HOTPLUG_CPU. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> --- kernel/rcuclassic.c | 2 +- kernel/rcutree.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/rcuclassic.c b/kernel/rcuclassic.c index 490934fc7ac3..bd5a9003497c 100644 --- a/kernel/rcuclassic.c +++ b/kernel/rcuclassic.c @@ -716,7 +716,7 @@ void rcu_check_callbacks(int cpu, int user) raise_rcu_softirq(); } -static void rcu_init_percpu_data(int cpu, struct rcu_ctrlblk *rcp, +static void __cpuinit rcu_init_percpu_data(int cpu, struct rcu_ctrlblk *rcp, struct rcu_data *rdp) { unsigned long flags; diff --git a/kernel/rcutree.c b/kernel/rcutree.c index f2d8638e6c60..b2fd602a6f6f 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -1314,7 +1314,7 @@ int rcu_needs_cpu(int cpu) * access due to the fact that this CPU cannot possibly have any RCU * callbacks in flight yet. */ -static void +static void __cpuinit rcu_init_percpu_data(int cpu, struct rcu_state *rsp) { unsigned long flags; -- cgit v1.2.3 From baf48f6577e581a9adb8fe849dc80e24b21d171d Mon Sep 17 00:00:00 2001 From: Mandeep Singh Baines <msb@google.com> Date: Mon, 12 Jan 2009 21:15:17 -0800 Subject: softlock: fix false panic which can occur if softlockup_thresh is reduced At run-time, if softlockup_thresh is changed to a much lower value, touch_timestamp is likely to be much older than the new softlock_thresh. This will cause a false softlockup to be detected. If softlockup_panic is enabled, the system will panic. The fix is to touch all watchdogs before changing softlockup_thresh. Signed-off-by: Mandeep Singh Baines <msb@google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> --- include/linux/sched.h | 3 +++ kernel/softlockup.c | 9 +++++++++ kernel/sysctl.c | 2 +- 3 files changed, 13 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/include/linux/sched.h b/include/linux/sched.h index 4cae9b81a1f8..54cbabf3b871 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -293,6 +293,9 @@ extern void sched_show_task(struct task_struct *p); extern void softlockup_tick(void); extern void touch_softlockup_watchdog(void); extern void touch_all_softlockup_watchdogs(void); +extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write, + struct file *filp, void __user *buffer, + size_t *lenp, loff_t *ppos); extern unsigned int softlockup_panic; extern unsigned long sysctl_hung_task_check_count; extern unsigned long sysctl_hung_task_timeout_secs; diff --git a/kernel/softlockup.c b/kernel/softlockup.c index d9188c66278a..85d5a2455103 100644 --- a/kernel/softlockup.c +++ b/kernel/softlockup.c @@ -16,6 +16,7 @@ #include <linux/lockdep.h> #include <linux/notifier.h> #include <linux/module.h> +#include <linux/sysctl.h> #include <asm/irq_regs.h> @@ -88,6 +89,14 @@ void touch_all_softlockup_watchdogs(void) } EXPORT_SYMBOL(touch_all_softlockup_watchdogs); +int proc_dosoftlockup_thresh(struct ctl_table *table, int write, + struct file *filp, void __user *buffer, + size_t *lenp, loff_t *ppos) +{ + touch_all_softlockup_watchdogs(); + return proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos); +} + /* * This callback runs from the timer interrupt, and checks * whether the watchdog thread has hung or not: diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 89d74436318c..596dc31a7116 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -800,7 +800,7 @@ static struct ctl_table kern_table[] = { .data = &softlockup_thresh, .maxlen = sizeof(int), .mode = 0644, - .proc_handler = &proc_dointvec_minmax, + .proc_handler = &proc_dosoftlockup_thresh, .strategy = &sysctl_intvec, .extra1 = &neg_one, .extra2 = &sixty, -- cgit v1.2.3 From b786c6a98ef6fa81114ba7b9fbfc0d67060775e3 Mon Sep 17 00:00:00 2001 From: Jiri Slaby <jirislaby@gmail.com> Date: Sat, 17 Jan 2009 12:04:36 +0100 Subject: relay: fix lock imbalance in relay_late_setup_files One fail path in relay_late_setup_files() omits mutex_unlock(&relay_channels_mutex); Add it. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> --- kernel/relay.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/relay.c b/kernel/relay.c index 09ac2008f77b..9d79b7854fa6 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -663,8 +663,10 @@ int relay_late_setup_files(struct rchan *chan, mutex_lock(&relay_channels_mutex); /* Is chan already set up? */ - if (unlikely(chan->has_base_filename)) + if (unlikely(chan->has_base_filename)) { + mutex_unlock(&relay_channels_mutex); return -EEXIST; + } chan->has_base_filename = 1; chan->parent = parent; curr_cpu = get_cpu(); -- cgit v1.2.3