diff options
author | Stephen Boyd <sboyd@codeaurora.org> | 2013-04-05 13:57:29 -0700 |
---|---|---|
committer | Tushar Behera <tushar.behera@linaro.org> | 2013-04-17 10:35:57 +0530 |
commit | 8eb9c669c037099a0ef7819fe4787efffe484122 (patch) | |
tree | 50f4f72751ee698d827cffa65d252741ca5e710f | |
parent | 12fd819eb71899226f7adf015f7cad597c500fb2 (diff) |
ARM: arch_timer: Silence debug preempt warnings
Hot-plugging with CONFIG_DEBUG_PREEMPT=y on a device with arm
architected timers causes a slew of "using smp_processor_id() in
preemptible" warnings:
BUG: using smp_processor_id() in preemptible [00000000] code: sh/111
caller is arch_timer_cpu_notify+0x14/0xc8
This happens because sometimes the cpu notifier,
arch_timer_cpu_notify(), is called in preemptible context and
other times in non-preemptible context but we use this_cpu_ptr()
to retrieve the clockevent in all cases. We're only going to
actually use the pointer in non-preemptible context though, so
push the this_cpu_ptr() access down into the cases to force the
checks to occur only in non-preemptible contexts.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
-rw-r--r-- | drivers/clocksource/arm_arch_timer.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index d7ad425ab9b..a65a710f998 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -248,14 +248,16 @@ static void __cpuinit arch_timer_stop(struct clock_event_device *clk) static int __cpuinit arch_timer_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) { - struct clock_event_device *evt = this_cpu_ptr(arch_timer_evt); - + /* + * Grab cpu pointer in each case to avoid spurious + * preemptible warnings + */ switch (action & ~CPU_TASKS_FROZEN) { case CPU_STARTING: - arch_timer_setup(evt); + arch_timer_setup(this_cpu_ptr(arch_timer_evt)); break; case CPU_DYING: - arch_timer_stop(evt); + arch_timer_stop(this_cpu_ptr(arch_timer_evt)); break; } |