cpuidle/x86/perf: fix power:cpu_idle double end events and throw cpu_idle events from the cpuidle layer

Currently intel_idle and acpi_idle driver show double cpu_idle "exit idle"
events -> this patch fixes it and makes cpu_idle events throwing less complex.

It also introduces cpu_idle events for all architectures which use
the cpuidle subsystem, namely:
  - arch/arm/mach-at91/cpuidle.c
  - arch/arm/mach-davinci/cpuidle.c
  - arch/arm/mach-kirkwood/cpuidle.c
  - arch/arm/mach-omap2/cpuidle34xx.c
  - arch/drivers/acpi/processor_idle.c (for all cases, not only mwait)
  - arch/x86/kernel/process.c (did throw events before, but was a mess)
  - drivers/idle/intel_idle.c (did throw events before)

Convention should be:
Fire cpu_idle events inside the current pm_idle function (not somewhere
down the the callee tree) to keep things easy.

Current possible pm_idle functions in X86:
c1e_idle, poll_idle, cpuidle_idle_call, mwait_idle, default_idle
-> this is really easy is now.

This affects userspace:
The type field of the cpu_idle power event can now direclty get
mapped to:
/sys/devices/system/cpu/cpuX/cpuidle/stateX/{name,desc,usage,time,...}
instead of throwing very CPU/mwait specific values.
This change is not visible for the intel_idle driver.
For the acpi_idle driver it should only be visible if the vendor
misses out C-states in his BIOS.
Another (perf timechart) patch reads out cpuidle info of cpu_idle
events from:
/sys/.../cpuidle/stateX/*, then the cpuidle events are mapped
to the correct C-/cpuidle state again, even if e.g. vendors miss
out C-states in their BIOS and for example only export C1 and C3.
-> everything is fine.

Signed-off-by: Thomas Renninger <trenn@suse.de>
CC: Robert Schoene <robert.schoene@tu-dresden.de>
CC: Jean Pihet <j-pihet@ti.com>
CC: Arjan van de Ven <arjan@linux.intel.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: linux-pm@lists.linux-foundation.org
CC: linux-acpi@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: linux-perf-users@vger.kernel.org
CC: linux-omap@vger.kernel.org
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 09c08a1c706f..67e96e67157b 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -386,6 +386,8 @@ void default_idle(void)
                 else
                         local_irq_enable();
                 current_thread_info()->status |= TS_POLLING;
+                trace_power_end(smp_processor_id());
+                trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id());
         } else {
                 local_irq_enable();
                 /* loop is done by the caller */
@@ -443,8 +445,6 @@ EXPORT_SYMBOL_GPL(cpu_idle_wait);
  */
 void mwait_idle_with_hints(unsigned long ax, unsigned long cx)
 {
-        trace_power_start(POWER_CSTATE, (ax>>4)+1, smp_processor_id());
-        trace_cpu_idle((ax>>4)+1, smp_processor_id());
         if (!need_resched()) {
                 if (cpu_has(__this_cpu_ptr(&cpu_info), X86_FEATURE_CLFLUSH_MONITOR))
                         clflush((void *)&current_thread_info()->flags);
@@ -471,6 +471,8 @@ static void mwait_idle(void)
                         __sti_mwait(0, 0);
                 else
                         local_irq_enable();
+                trace_power_end(smp_processor_id());
+                trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id());
         } else
                 local_irq_enable();
 }