diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-01-19 15:20:58 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-07-16 08:47:36 -0700 |
| commit | d1877392b4dce5d4c74d329777980d2a3ccede99 (patch) | |
| tree | 115e10ba46f06e4f0780f25c1518bfdcd5c1d86f | |
| parent | a6218ee909f993a8bd5138a5eb1bde620c12a2a9 (diff) | |
| download | kernel_samsung_crespo-d1877392b4dce5d4c74d329777980d2a3ccede99.zip kernel_samsung_crespo-d1877392b4dce5d4c74d329777980d2a3ccede99.tar.gz kernel_samsung_crespo-d1877392b4dce5d4c74d329777980d2a3ccede99.tar.bz2 | |
ARM: fix rcu stalls on SMP platforms
commit 7deabca0acfe02b8e18f59a4c95676012f49a304 upstream.
We can stall RCU processing on SMP platforms if a CPU sits in its idle
loop for a long time. This happens because we don't call irq_enter()
and irq_exit() around generic_smp_call_function_interrupt() and
friends. Add the necessary calls, and remove the one from within
ipi_timer(), so that they're all in a common place.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[add irq_enter()/irq_exit() in do_local_timer]
Signed-off-by: UCHINO Satoshi <satoshi.uchino@toshiba.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/arm/kernel/smp.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index fea97f6..4469924 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -445,9 +445,7 @@ static DEFINE_PER_CPU(struct clock_event_device, percpu_clockevent); static void ipi_timer(void) { struct clock_event_device *evt = &__get_cpu_var(percpu_clockevent); - irq_enter(); evt->event_handler(evt); - irq_exit(); } #ifdef CONFIG_LOCAL_TIMERS @@ -458,7 +456,9 @@ asmlinkage void __exception_irq_entry do_local_timer(struct pt_regs *regs) if (local_timer_ack()) { __inc_irq_stat(cpu, local_timer_irqs); + irq_enter(); ipi_timer(); + irq_exit(); } set_irq_regs(old_regs); @@ -568,7 +568,9 @@ asmlinkage void __exception_irq_entry do_IPI(int ipinr, struct pt_regs *regs) switch (ipinr) { case IPI_TIMER: + irq_enter(); ipi_timer(); + irq_exit(); break; case IPI_RESCHEDULE: @@ -576,15 +578,21 @@ asmlinkage void __exception_irq_entry do_IPI(int ipinr, struct pt_regs *regs) break; case IPI_CALL_FUNC: + irq_enter(); generic_smp_call_function_interrupt(); + irq_exit(); break; case IPI_CALL_FUNC_SINGLE: + irq_enter(); generic_smp_call_function_single_interrupt(); + irq_exit(); break; case IPI_CPU_STOP: + irq_enter(); ipi_cpu_stop(cpu); + irq_exit(); break; default: |