2022-05-27 21:30:57

by Eiichi Tsukata

Subject: [PATCH v4] cpuidle: haltpoll: Add trace points for guest_halt_poll_ns grow/shrink

Add trace points as are implemented in KVM host halt polling.
This helps tune guest halt polling params.

Signed-off-by: Eiichi Tsukata <[email protected]>
---
drivers/cpuidle/governors/haltpoll.c | 3 +++
include/trace/events/power.h | 29 ++++++++++++++++++++++++++++
2 files changed, 32 insertions(+)

diff --git a/drivers/cpuidle/governors/haltpoll.c b/drivers/cpuidle/governors/haltpoll.c
index cb2a96eafc02..1dff3a52917d 100644
--- a/drivers/cpuidle/governors/haltpoll.c
+++ b/drivers/cpuidle/governors/haltpoll.c
@@ -19,6 +19,7 @@
#include <linux/sched.h>
#include <linux/module.h>
#include <linux/kvm_para.h>
+#include <trace/events/power.h>

static unsigned int guest_halt_poll_ns __read_mostly = 200000;
module_param(guest_halt_poll_ns, uint, 0644);
@@ -90,6 +91,7 @@ static void adjust_poll_limit(struct cpuidle_device *dev, u64 block_ns)
if (val > guest_halt_poll_ns)
val = guest_halt_poll_ns;

+ trace_guest_halt_poll_ns_grow(val, dev->poll_limit_ns);
dev->poll_limit_ns = val;
} else if (block_ns > guest_halt_poll_ns &&
guest_halt_poll_allow_shrink) {
@@ -100,6 +102,7 @@ static void adjust_poll_limit(struct cpuidle_device *dev, u64 block_ns)
val = 0;
else
val /= shrink;
+ trace_guest_halt_poll_ns_shrink(val, dev->poll_limit_ns);
dev->poll_limit_ns = val;
}
}
diff --git a/include/trace/events/power.h b/include/trace/events/power.h
index af5018aa9517..c708521e4ed5 100644
--- a/include/trace/events/power.h
+++ b/include/trace/events/power.h
@@ -500,6 +500,35 @@ DEFINE_EVENT(dev_pm_qos_request, dev_pm_qos_remove_request,

TP_ARGS(name, type, new_value)
);
+
+TRACE_EVENT(guest_halt_poll_ns,
+
+ TP_PROTO(bool grow, unsigned int new, unsigned int old),
+
+ TP_ARGS(grow, new, old),
+
+ TP_STRUCT__entry(
+ __field(bool, grow)
+ __field(unsigned int, new)
+ __field(unsigned int, old)
+ ),
+
+ TP_fast_assign(
+ __entry->grow = grow;
+ __entry->new = new;
+ __entry->old = old;
+ ),
+
+ TP_printk("halt_poll_ns %u (%s %u)",
+ __entry->new,
+ __entry->grow ? "grow" : "shrink",
+ __entry->old)
+);
+
+#define trace_guest_halt_poll_ns_grow(new, old) \
+ trace_guest_halt_poll_ns(true, new, old)
+#define trace_guest_halt_poll_ns_shrink(new, old) \
+ trace_guest_halt_poll_ns(false, new, old)
#endif /* _TRACE_POWER_H */

/* This part must be outside protection */
--
2.36.1

2022-06-01 20:27:58

by Marcelo Tosatti

Subject: Re: [PATCH v4] cpuidle: haltpoll: Add trace points for guest_halt_poll_ns grow/shrink

On Fri, May 27, 2022 at 12:53:45AM +0000, Eiichi Tsukata wrote:
> Add trace points as are implemented in KVM host halt polling.
> This helps tune guest halt polling params.
>
> Signed-off-by: Eiichi Tsukata <[email protected]>
> ---
> drivers/cpuidle/governors/haltpoll.c | 3 +++
> include/trace/events/power.h | 29 ++++++++++++++++++++++++++++
> 2 files changed, 32 insertions(+)
>
> diff --git a/drivers/cpuidle/governors/haltpoll.c b/drivers/cpuidle/governors/haltpoll.c
> index cb2a96eafc02..1dff3a52917d 100644
> --- a/drivers/cpuidle/governors/haltpoll.c
> +++ b/drivers/cpuidle/governors/haltpoll.c
> @@ -19,6 +19,7 @@
> #include <linux/sched.h>
> #include <linux/module.h>
> #include <linux/kvm_para.h>
> +#include <trace/events/power.h>
>
> static unsigned int guest_halt_poll_ns __read_mostly = 200000;
> module_param(guest_halt_poll_ns, uint, 0644);
> @@ -90,6 +91,7 @@ static void adjust_poll_limit(struct cpuidle_device *dev, u64 block_ns)
> if (val > guest_halt_poll_ns)
> val = guest_halt_poll_ns;
>
> + trace_guest_halt_poll_ns_grow(val, dev->poll_limit_ns);
> dev->poll_limit_ns = val;
> } else if (block_ns > guest_halt_poll_ns &&
> guest_halt_poll_allow_shrink) {
> @@ -100,6 +102,7 @@ static void adjust_poll_limit(struct cpuidle_device *dev, u64 block_ns)
> val = 0;
> else
> val /= shrink;
> + trace_guest_halt_poll_ns_shrink(val, dev->poll_limit_ns);
> dev->poll_limit_ns = val;
> }
> }
> diff --git a/include/trace/events/power.h b/include/trace/events/power.h
> index af5018aa9517..c708521e4ed5 100644
> --- a/include/trace/events/power.h
> +++ b/include/trace/events/power.h
> @@ -500,6 +500,35 @@ DEFINE_EVENT(dev_pm_qos_request, dev_pm_qos_remove_request,
>
> TP_ARGS(name, type, new_value)
> );
> +
> +TRACE_EVENT(guest_halt_poll_ns,
> +
> + TP_PROTO(bool grow, unsigned int new, unsigned int old),
> +
> + TP_ARGS(grow, new, old),
> +
> + TP_STRUCT__entry(
> + __field(bool, grow)
> + __field(unsigned int, new)
> + __field(unsigned int, old)
> + ),
> +
> + TP_fast_assign(
> + __entry->grow = grow;
> + __entry->new = new;
> + __entry->old = old;
> + ),
> +
> + TP_printk("halt_poll_ns %u (%s %u)",
> + __entry->new,
> + __entry->grow ? "grow" : "shrink",
> + __entry->old)
> +);
> +
> +#define trace_guest_halt_poll_ns_grow(new, old) \
> + trace_guest_halt_poll_ns(true, new, old)
> +#define trace_guest_halt_poll_ns_shrink(new, old) \
> + trace_guest_halt_poll_ns(false, new, old)
> #endif /* _TRACE_POWER_H */
>
> /* This part must be outside protection */
> --
> 2.36.1
>
>

Signed-off-by: Marcelo Tosatti <[email protected]>

2022-06-14 14:05:26

by Rafael J. Wysocki

Subject: Re: [PATCH v4] cpuidle: haltpoll: Add trace points for guest_halt_poll_ns grow/shrink

On Mon, May 30, 2022 at 7:37 PM Marcelo Tosatti <[email protected]> wrote:
>
> On Fri, May 27, 2022 at 12:53:45AM +0000, Eiichi Tsukata wrote:
> > Add trace points as are implemented in KVM host halt polling.
> > This helps tune guest halt polling params.
> >
> > Signed-off-by: Eiichi Tsukata <[email protected]>
> > ---
> > drivers/cpuidle/governors/haltpoll.c | 3 +++
> > include/trace/events/power.h | 29 ++++++++++++++++++++++++++++
> > 2 files changed, 32 insertions(+)
> >
> > diff --git a/drivers/cpuidle/governors/haltpoll.c b/drivers/cpuidle/governors/haltpoll.c
> > index cb2a96eafc02..1dff3a52917d 100644
> > --- a/drivers/cpuidle/governors/haltpoll.c
> > +++ b/drivers/cpuidle/governors/haltpoll.c
> > @@ -19,6 +19,7 @@
> > #include <linux/sched.h>
> > #include <linux/module.h>
> > #include <linux/kvm_para.h>
> > +#include <trace/events/power.h>
> >
> > static unsigned int guest_halt_poll_ns __read_mostly = 200000;
> > module_param(guest_halt_poll_ns, uint, 0644);
> > @@ -90,6 +91,7 @@ static void adjust_poll_limit(struct cpuidle_device *dev, u64 block_ns)
> > if (val > guest_halt_poll_ns)
> > val = guest_halt_poll_ns;
> >
> > + trace_guest_halt_poll_ns_grow(val, dev->poll_limit_ns);
> > dev->poll_limit_ns = val;
> > } else if (block_ns > guest_halt_poll_ns &&
> > guest_halt_poll_allow_shrink) {
> > @@ -100,6 +102,7 @@ static void adjust_poll_limit(struct cpuidle_device *dev, u64 block_ns)
> > val = 0;
> > else
> > val /= shrink;
> > + trace_guest_halt_poll_ns_shrink(val, dev->poll_limit_ns);
> > dev->poll_limit_ns = val;
> > }
> > }
> > diff --git a/include/trace/events/power.h b/include/trace/events/power.h
> > index af5018aa9517..c708521e4ed5 100644
> > --- a/include/trace/events/power.h
> > +++ b/include/trace/events/power.h
> > @@ -500,6 +500,35 @@ DEFINE_EVENT(dev_pm_qos_request, dev_pm_qos_remove_request,
> >
> > TP_ARGS(name, type, new_value)
> > );
> > +
> > +TRACE_EVENT(guest_halt_poll_ns,
> > +
> > + TP_PROTO(bool grow, unsigned int new, unsigned int old),
> > +
> > + TP_ARGS(grow, new, old),
> > +
> > + TP_STRUCT__entry(
> > + __field(bool, grow)
> > + __field(unsigned int, new)
> > + __field(unsigned int, old)
> > + ),
> > +
> > + TP_fast_assign(
> > + __entry->grow = grow;
> > + __entry->new = new;
> > + __entry->old = old;
> > + ),
> > +
> > + TP_printk("halt_poll_ns %u (%s %u)",
> > + __entry->new,
> > + __entry->grow ? "grow" : "shrink",
> > + __entry->old)
> > +);
> > +
> > +#define trace_guest_halt_poll_ns_grow(new, old) \
> > + trace_guest_halt_poll_ns(true, new, old)
> > +#define trace_guest_halt_poll_ns_shrink(new, old) \
> > + trace_guest_halt_poll_ns(false, new, old)
> > #endif /* _TRACE_POWER_H */
> >
> > /* This part must be outside protection */
> > --
> > 2.36.1
> >
> >
>
> Signed-off-by: Marcelo Tosatti <[email protected]>

I took this as an ACK and applied the patch as 5.20 material.

Thanks!