[PATCH] x86: add power_end event to process_*.c cpu_idle routine

From: Robert Schöne
Date: Mon Jun 14 2010 - 07:37:36 EST

From: Robert SchÃne <robert.schoene@xxxxxxxxxxxxx>

Systems using the idle thread from process_32.c and process_64.c do not
generate power_end events which could be traced using perf. This patch
adds the event generation for such systems.

Signed-off-by: Robert SchÃne <robert.schoene@xxxxxxxxxxxxx>
Acked-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>

The smp_processor_id() is given to power_end as i hope that the changed
interface defined in http://lkml.org/lkml/2010/4/27/271 will be part of
the standard tree one day. (It is currently part of the -mm tree.) As
long as this new interface is not included in the standard tree, this
patch won't make no harm. When it will be included, this code does not
have to be touched anymore.

arch/x86/kernel/process_32.c | 4 ++++
arch/x86/kernel/process_64.c | 5 +++++
2 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index f6c6266..134f5f9 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -58,6 +58,8 @@
#include <asm/ds.h>
#include <asm/debugreg.h>

+#include <trace/events/power.h>
asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");

@@ -112,6 +114,8 @@ void cpu_idle(void)
+ trace_power_end(smp_processor_id());
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 17cb329..01c55ed 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -52,6 +52,8 @@
#include <asm/ds.h>
#include <asm/debugreg.h>

+#include <trace/events/power.h>
asmlinkage extern void ret_from_fork(void);

DEFINE_PER_CPU(unsigned long, old_rsp);
@@ -139,6 +141,9 @@ void cpu_idle(void)
+ trace_power_end(smp_processor_id());
/* In many cases the interrupt that ended idle
has already called exit_idle. But some idle
loops can be woken up without interrupt. */

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