| Message ID | 1442413401-2955-1-git-send-email-jszhang@marvell.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Sep 16, 2015 at 03:23:21PM +0100, Jisheng Zhang wrote: > Currently, if cpuidle is disabled or not supported, powertop reports > zero wakeups and zero events. This is due to the cpu_idle tracepoints > are missing. > > This patch is to make cpu_idle tracepoints always available even if > cpuidle is disabled or not supported. > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Is there a reason why this code cannot be moved to the generic idle loop ? Thanks, Lorenzo > --- > arch/arm64/kernel/process.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c > index 223b093..f75b540 100644 > --- a/arch/arm64/kernel/process.c > +++ b/arch/arm64/kernel/process.c > @@ -44,6 +44,7 @@ > #include <linux/hw_breakpoint.h> > #include <linux/personality.h> > #include <linux/notifier.h> > +#include <trace/events/power.h> > > #include <asm/compat.h> > #include <asm/cacheflush.h> > @@ -75,8 +76,10 @@ void arch_cpu_idle(void) > * This should do all the clock switching and wait for interrupt > * tricks > */ > + trace_cpu_idle_rcuidle(1, smp_processor_id()); > cpu_do_idle(); > local_irq_enable(); > + trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); > } > > #ifdef CONFIG_HOTPLUG_CPU > -- > 2.5.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >
Dear Lorenzo, On Wed, 16 Sep 2015 15:47:38 +0100 Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > On Wed, Sep 16, 2015 at 03:23:21PM +0100, Jisheng Zhang wrote: > > Currently, if cpuidle is disabled or not supported, powertop reports > > zero wakeups and zero events. This is due to the cpu_idle tracepoints > > are missing. > > > > This patch is to make cpu_idle tracepoints always available even if > > cpuidle is disabled or not supported. > > > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > > Is there a reason why this code cannot be moved to the generic idle loop ? Do you mean the cpu_idle_loop() in kernel/sched/idle.c? To be honest, I dunno. Maybe kernel experts can give some hints. Thanks, Jisheng > > Thanks, > Lorenzo > > > --- > > arch/arm64/kernel/process.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c > > index 223b093..f75b540 100644 > > --- a/arch/arm64/kernel/process.c > > +++ b/arch/arm64/kernel/process.c > > @@ -44,6 +44,7 @@ > > #include <linux/hw_breakpoint.h> > > #include <linux/personality.h> > > #include <linux/notifier.h> > > +#include <trace/events/power.h> > > > > #include <asm/compat.h> > > #include <asm/cacheflush.h> > > @@ -75,8 +76,10 @@ void arch_cpu_idle(void) > > * This should do all the clock switching and wait for interrupt > > * tricks > > */ > > + trace_cpu_idle_rcuidle(1, smp_processor_id()); > > cpu_do_idle(); > > local_irq_enable(); > > + trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); > > } > > > > #ifdef CONFIG_HOTPLUG_CPU > > -- > > 2.5.1 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/ > >
Dear Lorenzo, On Wed, 16 Sep 2015 22:53:12 +0800 Jisheng Zhang <jszhang@marvell.com> wrote: > Dear Lorenzo, > > On Wed, 16 Sep 2015 15:47:38 +0100 > Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > > > On Wed, Sep 16, 2015 at 03:23:21PM +0100, Jisheng Zhang wrote: > > > Currently, if cpuidle is disabled or not supported, powertop reports > > > zero wakeups and zero events. This is due to the cpu_idle tracepoints > > > are missing. > > > > > > This patch is to make cpu_idle tracepoints always available even if > > > cpuidle is disabled or not supported. > > > > > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > > > > Is there a reason why this code cannot be moved to the generic idle loop ? > > Do you mean the cpu_idle_loop() in kernel/sched/idle.c? To be honest, I Maybe I know now. we need to trace different idle level, for example: WFI idle: trace_cpu_idle_rcuidle(1, ...); deeper idle: trace_cpu_idle_rcuidle(2, ...); Usually, the first argument of trace_cpu_idle_rcuidle() equals to the index of the idle level. so generic idle loop is not a good candidate. > dunno. Maybe kernel experts can give some hints. > > Thanks, > Jisheng > > > > > Thanks, > > Lorenzo > > > > > --- > > > arch/arm64/kernel/process.c | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > > > diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c > > > index 223b093..f75b540 100644 > > > --- a/arch/arm64/kernel/process.c > > > +++ b/arch/arm64/kernel/process.c > > > @@ -44,6 +44,7 @@ > > > #include <linux/hw_breakpoint.h> > > > #include <linux/personality.h> > > > #include <linux/notifier.h> > > > +#include <trace/events/power.h> > > > > > > #include <asm/compat.h> > > > #include <asm/cacheflush.h> > > > @@ -75,8 +76,10 @@ void arch_cpu_idle(void) > > > * This should do all the clock switching and wait for interrupt > > > * tricks > > > */ > > > + trace_cpu_idle_rcuidle(1, smp_processor_id()); > > > cpu_do_idle(); > > > local_irq_enable(); > > > + trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); > > > } > > > > > > #ifdef CONFIG_HOTPLUG_CPU > > > -- > > > 2.5.1 > > > > > > -- > > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > > the body of a message to majordomo@vger.kernel.org > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > Please read the FAQ at http://www.tux.org/lkml/ > > > > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Wed, Sep 16, 2015 at 04:11:05PM +0100, Jisheng Zhang wrote: > Dear Lorenzo, > > On Wed, 16 Sep 2015 22:53:12 +0800 > Jisheng Zhang <jszhang@marvell.com> wrote: > > > Dear Lorenzo, > > > > On Wed, 16 Sep 2015 15:47:38 +0100 > > Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > > > > > On Wed, Sep 16, 2015 at 03:23:21PM +0100, Jisheng Zhang wrote: > > > > Currently, if cpuidle is disabled or not supported, powertop reports > > > > zero wakeups and zero events. This is due to the cpu_idle tracepoints > > > > are missing. > > > > > > > > This patch is to make cpu_idle tracepoints always available even if > > > > cpuidle is disabled or not supported. > > > > > > > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > > > > > > Is there a reason why this code cannot be moved to the generic idle loop ? > > > > Do you mean the cpu_idle_loop() in kernel/sched/idle.c? To be honest, I > > Maybe I know now. we need to trace different idle level, for example: > > WFI idle: trace_cpu_idle_rcuidle(1, ...); > > deeper idle: trace_cpu_idle_rcuidle(2, ...); > > Usually, the first argument of trace_cpu_idle_rcuidle() equals to the index > of the idle level. > > so generic idle loop is not a good candidate. You are adding a trace for tracing state 1 (ie default idle state), called from arch_cpu_idle(), which is the default idle call when the CPUidle framework is not available, so I suggested moving the traces you add to arm/arm64 arch_cpu_idle() calls to kernel/sched/idle.c (see default_idle_call()) instead of patching architecture code. I think you can't do that because on x86 calling arch_cpu_idle() does not always mean entering idle state index 1 if I read the code correctly (in particular the mwait based implementation - mwait_idle()). So never mind, patch is fine (on arm64, on arm you should be careful because some arm_pm_idle implementations trace state 1 already - see omap3_pm_idle and if you add traces to arch_cpu_idle you should remove the traces from mach implementations). Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
On Wed, 16 Sep 2015 17:16:05 +0100 Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > On Wed, Sep 16, 2015 at 04:11:05PM +0100, Jisheng Zhang wrote: > > Dear Lorenzo, > > > > On Wed, 16 Sep 2015 22:53:12 +0800 > > Jisheng Zhang <jszhang@marvell.com> wrote: > > > > > Dear Lorenzo, > > > > > > On Wed, 16 Sep 2015 15:47:38 +0100 > > > Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > > > > > > > On Wed, Sep 16, 2015 at 03:23:21PM +0100, Jisheng Zhang wrote: > > > > > Currently, if cpuidle is disabled or not supported, powertop reports > > > > > zero wakeups and zero events. This is due to the cpu_idle tracepoints > > > > > are missing. > > > > > > > > > > This patch is to make cpu_idle tracepoints always available even if > > > > > cpuidle is disabled or not supported. > > > > > > > > > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > > > > > > > > Is there a reason why this code cannot be moved to the generic idle loop ? > > > > > > Do you mean the cpu_idle_loop() in kernel/sched/idle.c? To be honest, I > > > > Maybe I know now. we need to trace different idle level, for example: > > > > WFI idle: trace_cpu_idle_rcuidle(1, ...); > > > > deeper idle: trace_cpu_idle_rcuidle(2, ...); > > > > Usually, the first argument of trace_cpu_idle_rcuidle() equals to the index > > of the idle level. > > > > so generic idle loop is not a good candidate. > > You are adding a trace for tracing state 1 (ie default idle state), > called from arch_cpu_idle(), which is the default idle call when the > CPUidle framework is not available, so I suggested moving the traces > you add to arm/arm64 arch_cpu_idle() calls to kernel/sched/idle.c > (see default_idle_call()) instead of patching architecture code. > > I think you can't do that because on x86 calling arch_cpu_idle() > does not always mean entering idle state index 1 if I read the code > correctly (in particular the mwait based implementation - mwait_idle()). > > So never mind, patch is fine (on arm64, on arm you should be careful > because some arm_pm_idle implementations trace state 1 already - > see omap3_pm_idle and if you add traces to arch_cpu_idle you should > remove the traces from mach implementations). OOPs, I was debugging the cascaded irq issues on Marvell BG4CT SoC. Yes, this arm_pm_idle should be taken care on arm, I should ignore arm_pm_idle, I'll cook v2 for arm platform. Thanks a lot, Jisheng > > Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
On Wed, Sep 16, 2015 at 10:23:21PM +0800, Jisheng Zhang wrote: > Currently, if cpuidle is disabled or not supported, powertop reports > zero wakeups and zero events. This is due to the cpu_idle tracepoints > are missing. > > This patch is to make cpu_idle tracepoints always available even if > cpuidle is disabled or not supported. > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Queued for 4.4. Thanks.
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 223b093..f75b540 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -44,6 +44,7 @@ #include <linux/hw_breakpoint.h> #include <linux/personality.h> #include <linux/notifier.h> +#include <trace/events/power.h> #include <asm/compat.h> #include <asm/cacheflush.h> @@ -75,8 +76,10 @@ void arch_cpu_idle(void) * This should do all the clock switching and wait for interrupt * tricks */ + trace_cpu_idle_rcuidle(1, smp_processor_id()); cpu_do_idle(); local_irq_enable(); + trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); } #ifdef CONFIG_HOTPLUG_CPU
Currently, if cpuidle is disabled or not supported, powertop reports zero wakeups and zero events. This is due to the cpu_idle tracepoints are missing. This patch is to make cpu_idle tracepoints always available even if cpuidle is disabled or not supported. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> --- arch/arm64/kernel/process.c | 3 +++ 1 file changed, 3 insertions(+)