From 9e9731043477db98a750c99f7d008fed01ca343d Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 5 Jul 2012 11:24:00 -0700 Subject: [PATCH] 3.0-stable patches added patches: arm-fix-rcu-stalls-on-smp-platforms.patch --- .../arm-fix-rcu-stalls-on-smp-platforms.patch | 67 +++++++++++++++++++ queue-3.0/series | 1 + 2 files changed, 68 insertions(+) create mode 100644 queue-3.0/arm-fix-rcu-stalls-on-smp-platforms.patch diff --git a/queue-3.0/arm-fix-rcu-stalls-on-smp-platforms.patch b/queue-3.0/arm-fix-rcu-stalls-on-smp-platforms.patch new file mode 100644 index 00000000000..e2c6270437c --- /dev/null +++ b/queue-3.0/arm-fix-rcu-stalls-on-smp-platforms.patch @@ -0,0 +1,67 @@ +From 7deabca0acfe02b8e18f59a4c95676012f49a304 Mon Sep 17 00:00:00 2001 +From: Russell King +Date: Thu, 19 Jan 2012 15:20:58 +0000 +Subject: ARM: fix rcu stalls on SMP platforms + +From: Russell King + +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 +Signed-off-by: UCHINO Satoshi +Signed-off-by: Greg Kroah-Hartman + +--- + arch/arm/kernel/smp.c | 10 ++++++++-- + 1 file changed, 8 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 +@@ -568,7 +566,9 @@ asmlinkage void __exception_irq_entry do + + switch (ipinr) { + case IPI_TIMER: ++ irq_enter(); + ipi_timer(); ++ irq_exit(); + break; + + case IPI_RESCHEDULE: +@@ -576,15 +576,21 @@ 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: diff --git a/queue-3.0/series b/queue-3.0/series index 081d197661c..5e433aa1b85 100644 --- a/queue-3.0/series +++ b/queue-3.0/series @@ -1,3 +1,4 @@ alsa-hda-add-realtek-alc280-codec-support.patch powerpc-xmon-use-cpumask-iterator-to-avoid-warning.patch media-smsusb-add-autodetection-support-for-usb-id-2040-f5a0.patch +arm-fix-rcu-stalls-on-smp-platforms.patch -- 2.47.3