2019-11-07 18:19:06

by Andi Kleen

[permalink] [raw]
Subject: [PATCH v5 09/13] perf evsel: Support opening on a specific CPU

From: Andi Kleen <[email protected]>

Support opening an evsel on a specific CPU index. Fix up
all callers so far to still open on all CPUs.

Signed-off-by: Andi Kleen <[email protected]>
---
tools/perf/tests/event-times.c | 4 ++--
tools/perf/util/evsel.c | 18 +++++++++++++-----
tools/perf/util/evsel.h | 3 ++-
tools/perf/util/stat.c | 2 +-
4 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/tools/perf/tests/event-times.c b/tools/perf/tests/event-times.c
index 1ee8704e2284..1e8a9f5c356d 100644
--- a/tools/perf/tests/event-times.c
+++ b/tools/perf/tests/event-times.c
@@ -125,7 +125,7 @@ static int attach__cpu_disabled(struct evlist *evlist)

evsel->core.attr.disabled = 1;

- err = perf_evsel__open_per_cpu(evsel, cpus);
+ err = perf_evsel__open_per_cpu(evsel, cpus, -1);
if (err) {
if (err == -EACCES)
return TEST_SKIP;
@@ -152,7 +152,7 @@ static int attach__cpu_enabled(struct evlist *evlist)
return -1;
}

- err = perf_evsel__open_per_cpu(evsel, cpus);
+ err = perf_evsel__open_per_cpu(evsel, cpus, -1);
if (err == -EACCES)
return TEST_SKIP;

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index d4451846af93..7106f9a067df 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1569,8 +1569,9 @@ static int perf_event_open(struct evsel *evsel,
return fd;
}

-int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
- struct perf_thread_map *threads)
+static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
+ struct perf_thread_map *threads,
+ int start_cpu, int end_cpu)
{
int cpu, thread, nthreads;
unsigned long flags = PERF_FLAG_FD_CLOEXEC;
@@ -1647,7 +1648,7 @@ int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,

display_attr(&evsel->core.attr);

- for (cpu = 0; cpu < cpus->nr; cpu++) {
+ for (cpu = start_cpu; cpu < end_cpu; cpu++) {

for (thread = 0; thread < nthreads; thread++) {
int fd, group_fd;
@@ -1825,6 +1826,12 @@ int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
return err;
}

+int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
+ struct perf_thread_map *threads)
+{
+ return evsel__open_cpu(evsel, cpus, threads, 0, cpus ? cpus->nr : 1);
+}
+
void evsel__close(struct evsel *evsel)
{
perf_evsel__close(&evsel->core);
@@ -1832,9 +1839,10 @@ void evsel__close(struct evsel *evsel)
}

int perf_evsel__open_per_cpu(struct evsel *evsel,
- struct perf_cpu_map *cpus)
+ struct perf_cpu_map *cpus,
+ int cpu)
{
- return evsel__open(evsel, cpus, NULL);
+ return evsel__open_cpu(evsel, cpus, NULL, cpu, cpu + 1);
}

int perf_evsel__open_per_thread(struct evsel *evsel,
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index b10d5ba21966..54513d70c109 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -223,7 +223,8 @@ int evsel__enable(struct evsel *evsel);
int evsel__disable(struct evsel *evsel);

int perf_evsel__open_per_cpu(struct evsel *evsel,
- struct perf_cpu_map *cpus);
+ struct perf_cpu_map *cpus,
+ int cpu);
int perf_evsel__open_per_thread(struct evsel *evsel,
struct perf_thread_map *threads);
int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
index 6822e4ffe224..36dc95032e4c 100644
--- a/tools/perf/util/stat.c
+++ b/tools/perf/util/stat.c
@@ -517,7 +517,7 @@ int create_perf_stat_counter(struct evsel *evsel,
}

if (target__has_cpu(target) && !target__has_per_thread(target))
- return perf_evsel__open_per_cpu(evsel, evsel__cpus(evsel));
+ return perf_evsel__open_per_cpu(evsel, evsel__cpus(evsel), -1);

return perf_evsel__open_per_thread(evsel, evsel->core.threads);
}
--
2.23.0


2019-11-11 13:32:15

by Jiri Olsa

[permalink] [raw]
Subject: Re: [PATCH v5 09/13] perf evsel: Support opening on a specific CPU

On Thu, Nov 07, 2019 at 10:16:42AM -0800, Andi Kleen wrote:
> From: Andi Kleen <[email protected]>

SNIP

> int perf_evsel__open_per_thread(struct evsel *evsel,
> diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> index b10d5ba21966..54513d70c109 100644
> --- a/tools/perf/util/evsel.h
> +++ b/tools/perf/util/evsel.h
> @@ -223,7 +223,8 @@ int evsel__enable(struct evsel *evsel);
> int evsel__disable(struct evsel *evsel);
>
> int perf_evsel__open_per_cpu(struct evsel *evsel,
> - struct perf_cpu_map *cpus);
> + struct perf_cpu_map *cpus,
> + int cpu);
> int perf_evsel__open_per_thread(struct evsel *evsel,
> struct perf_thread_map *threads);
> int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
> diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
> index 6822e4ffe224..36dc95032e4c 100644
> --- a/tools/perf/util/stat.c
> +++ b/tools/perf/util/stat.c
> @@ -517,7 +517,7 @@ int create_perf_stat_counter(struct evsel *evsel,
> }
>
> if (target__has_cpu(target) && !target__has_per_thread(target))
> - return perf_evsel__open_per_cpu(evsel, evsel__cpus(evsel));
> + return perf_evsel__open_per_cpu(evsel, evsel__cpus(evsel), -1);

how will -1 owrk in here? it will end up as:

perf_evsel__open_per_cpu
evsel__open_cpu( ...., start_cpu = -1, end_cpu = -1 + 1)
for (cpu = start_cpu; cpu < end_cpu; cpu++) {

?

jirka

2019-11-12 00:42:34

by Andi Kleen

[permalink] [raw]
Subject: Re: [PATCH v5 09/13] perf evsel: Support opening on a specific CPU

On Mon, Nov 11, 2019 at 02:30:33PM +0100, Jiri Olsa wrote:
> On Thu, Nov 07, 2019 at 10:16:42AM -0800, Andi Kleen wrote:
> > From: Andi Kleen <[email protected]>
>
> SNIP
>
> > int perf_evsel__open_per_thread(struct evsel *evsel,
> > diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> > index b10d5ba21966..54513d70c109 100644
> > --- a/tools/perf/util/evsel.h
> > +++ b/tools/perf/util/evsel.h
> > @@ -223,7 +223,8 @@ int evsel__enable(struct evsel *evsel);
> > int evsel__disable(struct evsel *evsel);
> >
> > int perf_evsel__open_per_cpu(struct evsel *evsel,
> > - struct perf_cpu_map *cpus);
> > + struct perf_cpu_map *cpus,
> > + int cpu);
> > int perf_evsel__open_per_thread(struct evsel *evsel,
> > struct perf_thread_map *threads);
> > int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
> > diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
> > index 6822e4ffe224..36dc95032e4c 100644
> > --- a/tools/perf/util/stat.c
> > +++ b/tools/perf/util/stat.c
> > @@ -517,7 +517,7 @@ int create_perf_stat_counter(struct evsel *evsel,
> > }
> >
> > if (target__has_cpu(target) && !target__has_per_thread(target))
> > - return perf_evsel__open_per_cpu(evsel, evsel__cpus(evsel));
> > + return perf_evsel__open_per_cpu(evsel, evsel__cpus(evsel), -1);
>
> how will -1 owrk in here? it will end up as:
>
> perf_evsel__open_per_cpu
> evsel__open_cpu( ...., start_cpu = -1, end_cpu = -1 + 1)
> for (cpu = start_cpu; cpu < end_cpu; cpu++) {

Yes you're right. The problem was the splitting of the patches.
With the two patches combined it works. So the end result is good,
just a bad intermediate step.

I will merge them again.

It seems better than creating something complicated here that
will just be undone next patch again.

-Andi