From: Greg KH <gre...@linuxfoundation.org>
3.0-stable review patch. If anyone has any objections, please let me know.
------------------
From: Russell King <rmk+ker...@arm.linux.org.uk>
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+ker...@arm.linux.org.uk>
[add irq_enter()/irq_exit() in do_local_timer]
Signed-off-by: UCHINO Satoshi <satoshi.uch...@toshiba.co.jp>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
arch/arm/kernel/smp.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -445,9 +445,7 @@ static DEFINE_PER_CPU(struct clock_event
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
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
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
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:
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
