[PATCH 3.12 017/146] clocksource: Exynos_mct: Use irq_force_affinity() in cpu bringup

Jiri Slaby
2014-06-09T09:26:21Z

From: Thomas Gleixner <tglx@linutronix.de>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 30ccf03b4a6a2102a2219058bdc6d779dc637dd7 upstream.

The starting cpu is not yet in the online mask so irq_set_affinity()
fails which results in per cpu timers for this cpu ending up on some
other online cpu, ususally cpu 0.

Use irq_force_affinity() which disables the online mask check and
makes things work.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Tomasz Figa <t.figa@samsung.com>,
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>,
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: linux-arm-kernel@lists.infradead.org,
Link: http://lkml.kernel.org/r/20140416143316.106665251@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/clocksource/exynos_mct.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c
index 62b0de6a1837..b17b3e0981f0 100644
--- a/drivers/clocksource/exynos_mct.c
+++ b/drivers/clocksource/exynos_mct.c
@@ -428,6 +428,7 @@ static int exynos4_local_timer_setup(struct clock_event_device *evt)
evt->irq);
return -EIO;
}
+ irq_force_affinity(mct_irqs[MCT_L0_IRQ + cpu], cpumask_of(cpu));
} else {
enable_percpu_irq(mct_irqs[MCT_L0_IRQ], 0);
}
@@ -448,7 +449,6 @@ static int exynos4_mct_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
struct mct_clock_event_device *mevt;
- unsigned int cpu;

/*
* Grab cpu pointer in each case to avoid spurious
@@ -459,12 +459,6 @@ static int exynos4_mct_cpu_notify(struct notifier_block *self,
mevt = this_cpu_ptr(&percpu_mct_tick);
exynos4_local_timer_setup(&mevt->evt);
break;
- case CPU_ONLINE:
- cpu = (unsigned long)hcpu;
- if (mct_int_type == MCT_INT_SPI)
- irq_set_affinity(mct_irqs[MCT_L0_IRQ + cpu],
- cpumask_of(cpu));
- break;
case CPU_DYING:
mevt = this_cpu_ptr(&percpu_mct_tick);
exynos4_local_timer_stop(&mevt->evt);
--
1.9.3