2010-11-23 15:21:52

by Franck Bui-Huu

[permalink] [raw]
Subject: [PATCH 1/3] perf: introduce is_sampling_event()

From: Franck Bui-Huu <[email protected]>

and use it when appropriate.

Signed-off-by: Franck Bui-Huu <[email protected]>
---
arch/x86/kernel/cpu/perf_event.c | 2 +-
include/linux/perf_event.h | 5 +++++
kernel/perf_event.c | 10 +++++-----
3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index ed63101..89aa0f8 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -437,7 +437,7 @@ static int x86_setup_perfctr(struct perf_event *event)
struct hw_perf_event *hwc = &event->hw;
u64 config;

- if (!hwc->sample_period) {
+ if (!is_sampling_event(event)) {
hwc->sample_period = x86_pmu.max_period;
hwc->last_period = hwc->sample_period;
local64_set(&hwc->period_left, hwc->sample_period);
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 40150f3..bb1884c 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -982,6 +982,11 @@ extern int perf_event_overflow(struct perf_event *event, int nmi,
struct perf_sample_data *data,
struct pt_regs *regs);

+static inline bool is_sampling_event(struct perf_event *event)
+{
+ return event->attr.sample_period != 0;
+}
+
/*
* Return 1 for a software event, 0 for a hardware event
*/
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index cb6c0d2..df7869f 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -2482,7 +2482,7 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg)
int ret = 0;
u64 value;

- if (!event->attr.sample_period)
+ if (!is_sampling_event(event))
return -EINVAL;

if (copy_from_user(&value, arg, sizeof(value)))
@@ -4353,7 +4353,7 @@ static void perf_swevent_event(struct perf_event *event, u64 nr,
if (!regs)
return;

- if (!hwc->sample_period)
+ if (!is_sampling_event(event))
return;

if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq)
@@ -4516,7 +4516,7 @@ static int perf_swevent_add(struct perf_event *event, int flags)
struct hw_perf_event *hwc = &event->hw;
struct hlist_head *head;

- if (hwc->sample_period) {
+ if (is_sampling_event(event)) {
hwc->last_period = hwc->sample_period;
perf_swevent_set_period(event);
}
@@ -4897,7 +4897,7 @@ static void perf_swevent_start_hrtimer(struct perf_event *event)

hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
hwc->hrtimer.function = perf_swevent_hrtimer;
- if (hwc->sample_period) {
+ if (is_sampling_event(event)) {
s64 period = local64_read(&hwc->period_left);

if (period) {
@@ -4918,7 +4918,7 @@ static void perf_swevent_cancel_hrtimer(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;

- if (hwc->sample_period) {
+ if (is_sampling_event(event)) {
ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer);
local64_set(&hwc->period_left, ktime_to_ns(remaining));

--
1.7.3.2


2010-11-23 15:21:55

by Franck Bui-Huu

[permalink] [raw]
Subject: [PATCH 2/3] perf: Limit event refresh to sampling event

From: Franck Bui-Huu <[email protected]>

Signed-off-by: Franck Bui-Huu <[email protected]>
---
kernel/perf_event.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index df7869f..813b09e 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -1072,7 +1072,7 @@ static int perf_event_refresh(struct perf_event *event, int refresh)
/*
* not supported on inherited events
*/
- if (event->attr.inherit)
+ if (event->attr.inherit || !is_sampling_event(event))
return -EINVAL;

atomic_add(refresh, &event->event_limit);
--
1.7.3.2

2010-11-23 15:22:03

by Franck Bui-Huu

[permalink] [raw]
Subject: [PATCH 3/3] perf: don't bother to init the hrtimer for no SW sampling counters

From: Franck Bui-Huu <[email protected]>

Signed-off-by: Franck Bui-Huu <[email protected]>
---
kernel/perf_event.c | 24 +++++++++++++-----------
1 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 813b09e..31515200 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4894,24 +4894,26 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
static void perf_swevent_start_hrtimer(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
+ s64 period;
+
+ if (!is_sampling_event(event))
+ return;

hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
hwc->hrtimer.function = perf_swevent_hrtimer;
- if (is_sampling_event(event)) {
- s64 period = local64_read(&hwc->period_left);

- if (period) {
- if (period < 0)
- period = 10000;
+ period = local64_read(&hwc->period_left);
+ if (period) {
+ if (period < 0)
+ period = 10000;

- local64_set(&hwc->period_left, 0);
- } else {
- period = max_t(u64, 10000, hwc->sample_period);
- }
- __hrtimer_start_range_ns(&hwc->hrtimer,
+ local64_set(&hwc->period_left, 0);
+ } else {
+ period = max_t(u64, 10000, hwc->sample_period);
+ }
+ __hrtimer_start_range_ns(&hwc->hrtimer,
ns_to_ktime(period), 0,
HRTIMER_MODE_REL_PINNED, 0);
- }
}

static void perf_swevent_cancel_hrtimer(struct perf_event *event)
--
1.7.3.2

Subject: [tip:perf/core] perf: Limit event refresh to sampling event

Commit-ID: 2e939d1da9b5628642314c1e68b4319e61263c94
Gitweb: http://git.kernel.org/tip/2e939d1da9b5628642314c1e68b4319e61263c94
Author: Franck Bui-Huu <[email protected]>
AuthorDate: Tue, 23 Nov 2010 16:21:44 +0100
Committer: Ingo Molnar <[email protected]>
CommitDate: Fri, 26 Nov 2010 15:14:55 +0100

perf: Limit event refresh to sampling event

Signed-off-by: Franck Bui-Huu <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
kernel/perf_event.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 8806984..027c4d3 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -1073,7 +1073,7 @@ static int perf_event_refresh(struct perf_event *event, int refresh)
/*
* not supported on inherited events
*/
- if (event->attr.inherit)
+ if (event->attr.inherit || !is_sampling_event(event))
return -EINVAL;

atomic_add(refresh, &event->event_limit);

Subject: [tip:perf/core] perf: Introduce is_sampling_event()

Commit-ID: 6c7e550f13f8ad82efb6a5653ae628c2543c1768
Gitweb: http://git.kernel.org/tip/6c7e550f13f8ad82efb6a5653ae628c2543c1768
Author: Franck Bui-Huu <[email protected]>
AuthorDate: Tue, 23 Nov 2010 16:21:43 +0100
Committer: Ingo Molnar <[email protected]>
CommitDate: Fri, 26 Nov 2010 15:14:54 +0100

perf: Introduce is_sampling_event()

and use it when appropriate.

Signed-off-by: Franck Bui-Huu <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
arch/x86/kernel/cpu/perf_event.c | 2 +-
include/linux/perf_event.h | 5 +++++
kernel/perf_event.c | 10 +++++-----
3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 7c1a4c3..c01dfec 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -442,7 +442,7 @@ static int x86_setup_perfctr(struct perf_event *event)
struct hw_perf_event *hwc = &event->hw;
u64 config;

- if (!hwc->sample_period) {
+ if (!is_sampling_event(event)) {
hwc->sample_period = x86_pmu.max_period;
hwc->last_period = hwc->sample_period;
local64_set(&hwc->period_left, hwc->sample_period);
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index de2c417..cbf04cc 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -969,6 +969,11 @@ extern int perf_event_overflow(struct perf_event *event, int nmi,
struct perf_sample_data *data,
struct pt_regs *regs);

+static inline bool is_sampling_event(struct perf_event *event)
+{
+ return event->attr.sample_period != 0;
+}
+
/*
* Return 1 for a software event, 0 for a hardware event
*/
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 43f757c..8806984 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -2514,7 +2514,7 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg)
int ret = 0;
u64 value;

- if (!event->attr.sample_period)
+ if (!is_sampling_event(event))
return -EINVAL;

if (copy_from_user(&value, arg, sizeof(value)))
@@ -4385,7 +4385,7 @@ static void perf_swevent_event(struct perf_event *event, u64 nr,
if (!regs)
return;

- if (!hwc->sample_period)
+ if (!is_sampling_event(event))
return;

if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq)
@@ -4548,7 +4548,7 @@ static int perf_swevent_add(struct perf_event *event, int flags)
struct hw_perf_event *hwc = &event->hw;
struct hlist_head *head;

- if (hwc->sample_period) {
+ if (is_sampling_event(event)) {
hwc->last_period = hwc->sample_period;
perf_swevent_set_period(event);
}
@@ -4920,7 +4920,7 @@ static void perf_swevent_start_hrtimer(struct perf_event *event)

hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
hwc->hrtimer.function = perf_swevent_hrtimer;
- if (hwc->sample_period) {
+ if (is_sampling_event(event)) {
s64 period = local64_read(&hwc->period_left);

if (period) {
@@ -4941,7 +4941,7 @@ static void perf_swevent_cancel_hrtimer(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;

- if (hwc->sample_period) {
+ if (is_sampling_event(event)) {
ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer);
local64_set(&hwc->period_left, ktime_to_ns(remaining));

Subject: [tip:perf/core] perf: Don't bother to init the hrtimer for no SW sampling counters

Commit-ID: 5d508e820a23d9b6e8a149dfaa8ba5cbedf3d95c
Gitweb: http://git.kernel.org/tip/5d508e820a23d9b6e8a149dfaa8ba5cbedf3d95c
Author: Franck Bui-Huu <[email protected]>
AuthorDate: Tue, 23 Nov 2010 16:21:45 +0100
Committer: Ingo Molnar <[email protected]>
CommitDate: Fri, 26 Nov 2010 15:14:55 +0100

perf: Don't bother to init the hrtimer for no SW sampling counters

Signed-off-by: Franck Bui-Huu <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
kernel/perf_event.c | 24 +++++++++++++-----------
1 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 027c4d3..98c5549 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4917,24 +4917,26 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
static void perf_swevent_start_hrtimer(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
+ s64 period;
+
+ if (!is_sampling_event(event))
+ return;

hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
hwc->hrtimer.function = perf_swevent_hrtimer;
- if (is_sampling_event(event)) {
- s64 period = local64_read(&hwc->period_left);

- if (period) {
- if (period < 0)
- period = 10000;
+ period = local64_read(&hwc->period_left);
+ if (period) {
+ if (period < 0)
+ period = 10000;

- local64_set(&hwc->period_left, 0);
- } else {
- period = max_t(u64, 10000, hwc->sample_period);
- }
- __hrtimer_start_range_ns(&hwc->hrtimer,
+ local64_set(&hwc->period_left, 0);
+ } else {
+ period = max_t(u64, 10000, hwc->sample_period);
+ }
+ __hrtimer_start_range_ns(&hwc->hrtimer,
ns_to_ktime(period), 0,
HRTIMER_MODE_REL_PINNED, 0);
- }
}

static void perf_swevent_cancel_hrtimer(struct perf_event *event)