From 01f8fa4f01d8362358eb90e412bd7ae18a3ec1ad Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 16 Apr 2014 14:36:44 +0000 Subject: genirq: Allow forcing cpu affinity of interrupts The current implementation of irq_set_affinity() refuses rightfully to route an interrupt to an offline cpu. But there is a special case, where this is actually desired. Some of the ARM SoCs have per cpu timers which require setting the affinity during cpu startup where the cpu is not yet in the online mask. If we can't do that, then the local timer interrupt for the about to become online cpu is routed to some random online cpu. The developers of the affected machines tried to work around that issue, but that results in a massive mess in that timer code. We have a yet unused argument in the set_affinity callbacks of the irq chips, which I added back then for a similar reason. It was never required so it got not used. But I'm happy that I never removed it. That allows us to implement a sane handling of the above scenario. So the affected SoC drivers can add the required force handling to their interrupt chip, switch the timer code to irq_force_affinity() and things just work. This does not affect any existing user of irq_set_affinity(). Tagged for stable to allow a simple fix of the affected SoC clock event drivers. Reported-and-tested-by: Krzysztof Kozlowski Signed-off-by: Thomas Gleixner Cc: Kyungmin Park Cc: Marek Szyprowski Cc: Bartlomiej Zolnierkiewicz Cc: Tomasz Figa , Cc: Daniel Lezcano , Cc: Kukjin Kim Cc: linux-arm-kernel@lists.infradead.org, Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20140416143315.717251504@linutronix.de Signed-off-by: Thomas Gleixner --- kernel/irq/manage.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) (limited to 'kernel') diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 2486a4c1a710..d34131ca372b 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -180,7 +180,7 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask, struct irq_chip *chip = irq_data_get_irq_chip(data); int ret; - ret = chip->irq_set_affinity(data, mask, false); + ret = chip->irq_set_affinity(data, mask, force); switch (ret) { case IRQ_SET_MASK_OK: cpumask_copy(data->affinity, mask); @@ -192,7 +192,8 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask, return ret; } -int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask) +int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask, + bool force) { struct irq_chip *chip = irq_data_get_irq_chip(data); struct irq_desc *desc = irq_data_to_desc(data); @@ -202,7 +203,7 @@ int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask) return -EINVAL; if (irq_can_move_pcntxt(data)) { - ret = irq_do_set_affinity(data, mask, false); + ret = irq_do_set_affinity(data, mask, force); } else { irqd_set_move_pending(data); irq_copy_pending(desc, mask); @@ -217,13 +218,7 @@ int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask) return ret; } -/** - * irq_set_affinity - Set the irq affinity of a given irq - * @irq: Interrupt to set affinity - * @mask: cpumask - * - */ -int irq_set_affinity(unsigned int irq, const struct cpumask *mask) +int __irq_set_affinity(unsigned int irq, const struct cpumask *mask, bool force) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; @@ -233,7 +228,7 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *mask) return -EINVAL; raw_spin_lock_irqsave(&desc->lock, flags); - ret = __irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask); + ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force); raw_spin_unlock_irqrestore(&desc->lock, flags); return ret; } -- cgit v1.2.3 From f3f125324fc1b8500cd20a2907628f7e5d88a708 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 20 Apr 2014 23:43:01 +0200 Subject: PM / suspend: Make cpuidle work in the "freeze" state The "freeze" system sleep state introduced by commit 7e73c5ae6e79 (PM: Introduce suspend state PM_SUSPEND_FREEZE) requires cpuidle to be functional when freeze_enter() is executed to work correctly (that is, to be able to save any more energy than runtime idle), but that is impossible after commit 8651f97bd951d (PM / cpuidle: System resume hang fix with cpuidle) which caused cpuidle to be paused in dpm_suspend_noirq() and resumed in dpm_resume_noirq(). To avoid that problem, add cpuidle_resume() and cpuidle_pause() to the beginning and the end of freeze_enter(), respectively. Reported-by: Zhang Rui Signed-off-by: Rafael J. Wysocki Reviewed-by: Preeti U Murthy --- kernel/power/suspend.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel') diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index c3ad9cafe930..8233cd4047d7 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -53,7 +54,9 @@ static void freeze_begin(void) static void freeze_enter(void) { + cpuidle_resume(); wait_event(suspend_freeze_wait_head, suspend_freeze_wake); + cpuidle_pause(); } void freeze_wake(void) -- cgit v1.2.3