[PATCH v2 3/3] libperf: Add perf_evsel__refresh() function

From: Charlie Jenkins
Date: Wed Aug 07 2024 - 20:03:21 EST


Introduce perf_evsel__refresh() to increment the overflow limit. Can
optionally enable the event immediately.

Co-developed-by: Shunsuke Nakamura <nakamura.shun@xxxxxxxxxxx>
Signed-off-by: Shunsuke Nakamura <nakamura.shun@xxxxxxxxxxx>
Signed-off-by: Charlie Jenkins <charlie@xxxxxxxxxxxx>
---
tools/lib/perf/Documentation/libperf.txt | 2 ++
tools/lib/perf/evsel.c | 49 ++++++++++++++++++++++++++------
tools/lib/perf/include/perf/evsel.h | 2 ++
tools/lib/perf/libperf.map | 2 ++
4 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/tools/lib/perf/Documentation/libperf.txt b/tools/lib/perf/Documentation/libperf.txt
index fcfb9499ef9c..a6c3bab5c995 100644
--- a/tools/lib/perf/Documentation/libperf.txt
+++ b/tools/lib/perf/Documentation/libperf.txt
@@ -147,6 +147,8 @@ SYNOPSIS
int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu_map_idx);
int perf_evsel__disable(struct perf_evsel *evsel);
int perf_evsel__disable_cpu(struct perf_evsel *evsel, int cpu_map_idx);
+ int perf_evsel__refresh(struct perf_evsel *evsel, int refresh, bool enable);
+ int perf_evsel__period(struct perf_evsel *evsel, int period);
struct perf_cpu_map *perf_evsel__cpus(struct perf_evsel *evsel);
struct perf_thread_map *perf_evsel__threads(struct perf_evsel *evsel);
struct perf_event_attr *perf_evsel__attr(struct perf_evsel *evsel);
diff --git a/tools/lib/perf/evsel.c b/tools/lib/perf/evsel.c
index c07160953224..2b7ca7fa4998 100644
--- a/tools/lib/perf/evsel.c
+++ b/tools/lib/perf/evsel.c
@@ -18,6 +18,7 @@
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <asm/bug.h>
+#include "internal.h"

void perf_evsel__init(struct perf_evsel *evsel, struct perf_event_attr *attr,
int idx)
@@ -412,7 +413,7 @@ int perf_evsel__read(struct perf_evsel *evsel, int cpu_map_idx, int thread,
return 0;
}

-static int perf_evsel__ioctl(struct perf_evsel *evsel, int ioc, void *arg,
+static int perf_evsel__ioctl(struct perf_evsel *evsel, int ioc, unsigned long arg,
int cpu_map_idx, int thread)
{
int *fd = FD(evsel, cpu_map_idx, thread);
@@ -424,7 +425,7 @@ static int perf_evsel__ioctl(struct perf_evsel *evsel, int ioc, void *arg,
}

static int perf_evsel__run_ioctl(struct perf_evsel *evsel,
- int ioc, void *arg,
+ int ioc, unsigned long arg,
int cpu_map_idx)
{
int thread;
@@ -441,7 +442,7 @@ static int perf_evsel__run_ioctl(struct perf_evsel *evsel,

int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu_map_idx)
{
- return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, cpu_map_idx);
+ return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, 0, cpu_map_idx);
}

int perf_evsel__enable_thread(struct perf_evsel *evsel, int thread)
@@ -451,7 +452,7 @@ int perf_evsel__enable_thread(struct perf_evsel *evsel, int thread)
int err;

perf_cpu_map__for_each_cpu(cpu, idx, evsel->cpus) {
- err = perf_evsel__ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, idx, thread);
+ err = perf_evsel__ioctl(evsel, PERF_EVENT_IOC_ENABLE, 0, idx, thread);
if (err)
return err;
}
@@ -465,13 +466,13 @@ int perf_evsel__enable(struct perf_evsel *evsel)
int err = 0;

for (i = 0; i < xyarray__max_x(evsel->fd) && !err; i++)
- err = perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, i);
+ err = perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, 0, i);
return err;
}

int perf_evsel__disable_cpu(struct perf_evsel *evsel, int cpu_map_idx)
{
- return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_DISABLE, NULL, cpu_map_idx);
+ return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_DISABLE, 0, cpu_map_idx);
}

int perf_evsel__disable(struct perf_evsel *evsel)
@@ -480,7 +481,39 @@ int perf_evsel__disable(struct perf_evsel *evsel)
int err = 0;

for (i = 0; i < xyarray__max_x(evsel->fd) && !err; i++)
- err = perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_DISABLE, NULL, i);
+ err = perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_DISABLE, 0, i);
+ return err;
+}
+
+int perf_evsel__refresh(struct perf_evsel *evsel, int refresh, bool enable)
+{
+ int i, ioc;
+ int err = 0;
+
+ ioc = enable ? PERF_EVENT_IOC_REFRESH : PERF_EVENT_IOC_INC_EVENT_LIMIT;
+
+ for (i = 0; i < xyarray__max_x(evsel->fd) && !err; i++)
+ err = perf_evsel__run_ioctl(evsel, ioc, refresh, i);
+ return err;
+}
+
+int perf_evsel__period(struct perf_evsel *evsel, __u64 period)
+{
+ struct perf_event_attr *attr;
+ int i;
+ int err = 0;
+
+ attr = perf_evsel__attr(evsel);
+
+ for (i = 0; i < xyarray__max_x(evsel->fd); i++) {
+ err = perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_PERIOD,
+ (unsigned long)&period, i);
+ if (err)
+ return err;
+ }
+
+ attr->sample_period = period;
+
return err;
}

@@ -491,7 +524,7 @@ int perf_evsel__apply_filter(struct perf_evsel *evsel, const char *filter)
for (i = 0; i < perf_cpu_map__nr(evsel->cpus) && !err; i++)
err = perf_evsel__run_ioctl(evsel,
PERF_EVENT_IOC_SET_FILTER,
- (void *)filter, i);
+ (unsigned long)filter, i);
return err;
}

diff --git a/tools/lib/perf/include/perf/evsel.h b/tools/lib/perf/include/perf/evsel.h
index 6f92204075c2..e562dd9f39e0 100644
--- a/tools/lib/perf/include/perf/evsel.h
+++ b/tools/lib/perf/include/perf/evsel.h
@@ -40,6 +40,8 @@ LIBPERF_API int perf_evsel__enable(struct perf_evsel *evsel);
LIBPERF_API int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu_map_idx);
LIBPERF_API int perf_evsel__enable_thread(struct perf_evsel *evsel, int thread);
LIBPERF_API int perf_evsel__disable(struct perf_evsel *evsel);
+LIBPERF_API int perf_evsel__refresh(struct perf_evsel *evsel, int refresh, bool enable);
+LIBPERF_API int perf_evsel__period(struct perf_evsel *evsel, __u64 period);
LIBPERF_API int perf_evsel__disable_cpu(struct perf_evsel *evsel, int cpu_map_idx);
LIBPERF_API struct perf_cpu_map *perf_evsel__cpus(struct perf_evsel *evsel);
LIBPERF_API struct perf_thread_map *perf_evsel__threads(struct perf_evsel *evsel);
diff --git a/tools/lib/perf/libperf.map b/tools/lib/perf/libperf.map
index 2aa79b696032..bb7a48befdd5 100644
--- a/tools/lib/perf/libperf.map
+++ b/tools/lib/perf/libperf.map
@@ -34,6 +34,8 @@ LIBPERF_0.0.1 {
perf_evsel__munmap;
perf_evsel__mmap_base;
perf_evsel__read;
+ perf_evsel__refresh;
+ perf_evsel__period;
perf_evsel__cpus;
perf_evsel__threads;
perf_evsel__attr;

--
2.45.0