Commit-ID: 00b42959106a9ca1c2899e591ae4e9a83ad6af05 Gitweb: http://git.kernel.org/tip/00b42959106a9ca1c2899e591ae4e9a83ad6af05 Author: Frederic Weisbecker <fweisbec@xxxxxxxxx> AuthorDate: Wed, 7 Nov 2012 21:03:07 +0100 Committer: Frederic Weisbecker <fweisbec@xxxxxxxxx> CommitDate: Sat, 17 Nov 2012 19:30:39 +0100 irq_work: Don't stop the tick with pending works Don't stop the tick if we have pending irq works on the queue, otherwise if the arch can't raise self-IPIs, we may not find an opportunity to execute the pending works for a while. Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx> Acked-by: Steven Rostedt <rostedt@xxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx> --- include/linux/irq_work.h | 6 ++++++ kernel/irq_work.c | 11 +++++++++++ kernel/time/tick-sched.c | 3 ++- 3 files changed, 19 insertions(+), 1 deletion(-) diff --git a/include/linux/irq_work.h b/include/linux/irq_work.h index 6a9e8f5..a69704f 100644 --- a/include/linux/irq_work.h +++ b/include/linux/irq_work.h @@ -20,4 +20,10 @@ bool irq_work_queue(struct irq_work *work); void irq_work_run(void); void irq_work_sync(struct irq_work *work); +#ifdef CONFIG_IRQ_WORK +bool irq_work_needs_cpu(void); +#else +static bool irq_work_needs_cpu(void) { return false; } +#endif + #endif /* _LINUX_IRQ_WORK_H */ diff --git a/kernel/irq_work.c b/kernel/irq_work.c index 64eddd5..b3c113a 100644 --- a/kernel/irq_work.c +++ b/kernel/irq_work.c @@ -99,6 +99,17 @@ bool irq_work_queue(struct irq_work *work) } EXPORT_SYMBOL_GPL(irq_work_queue); +bool irq_work_needs_cpu(void) +{ + struct llist_head *this_list; + + this_list = &__get_cpu_var(irq_work_list); + if (llist_empty(this_list)) + return false; + + return true; +} + /* * Run the irq_work entries on this cpu. Requires to be ran from hardirq * context with local IRQs disabled. diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 9e945aa..f249e8c 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -20,6 +20,7 @@ #include <linux/profile.h> #include <linux/sched.h> #include <linux/module.h> +#include <linux/irq_work.h> #include <asm/irq_regs.h> @@ -289,7 +290,7 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts, } while (read_seqretry(&xtime_lock, seq)); if (rcu_needs_cpu(cpu, &rcu_delta_jiffies) || printk_needs_cpu(cpu) || - arch_needs_cpu(cpu)) { + arch_needs_cpu(cpu) || irq_work_needs_cpu()) { next_jiffies = last_jiffies + 1; delta_jiffies = 1; } else { -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html