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| author | Jiri Olsa <jolsa@redhat.com> | 2021-07-06 17:17:03 +0200 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2021-07-09 14:49:47 -0300 |
| commit | 3fd35de1686bf809431c5f0137de8eee5a2811d6 (patch) | |
| tree | 0b89cc7a5fdd6ed6cd107685ffc52b81d8fbe298 /tools/lib | |
| parent | c47a5599eda324bacdacd125227a0925d6c50fbe (diff) | |
| download | lwn-3fd35de1686bf809431c5f0137de8eee5a2811d6.tar.gz lwn-3fd35de1686bf809431c5f0137de8eee5a2811d6.zip | |
libperf: Add group support to perf_evsel__open()
Add support to set group_fd in perf_evsel__open() and make it follow the
group setup.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Requested-by: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210706151704.73662-7-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/perf/evsel.c | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/tools/lib/perf/evsel.c b/tools/lib/perf/evsel.c index 3e6638d27c45..9ebf7122d476 100644 --- a/tools/lib/perf/evsel.c +++ b/tools/lib/perf/evsel.c @@ -17,6 +17,7 @@ #include <linux/string.h> #include <sys/ioctl.h> #include <sys/mman.h> +#include <asm/bug.h> void perf_evsel__init(struct perf_evsel *evsel, struct perf_event_attr *attr, int idx) @@ -76,6 +77,25 @@ sys_perf_event_open(struct perf_event_attr *attr, return syscall(__NR_perf_event_open, attr, pid, cpu, group_fd, flags); } +static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread) +{ + struct perf_evsel *leader = evsel->leader; + int fd; + + if (evsel == leader) + return -1; + + /* + * Leader must be already processed/open, + * if not it's a bug. + */ + BUG_ON(!leader->fd); + + fd = FD(leader, cpu, thread); + BUG_ON(fd == -1); + return fd; +} + int perf_evsel__open(struct perf_evsel *evsel, struct perf_cpu_map *cpus, struct perf_thread_map *threads) { @@ -111,11 +131,13 @@ int perf_evsel__open(struct perf_evsel *evsel, struct perf_cpu_map *cpus, for (cpu = 0; cpu < cpus->nr; cpu++) { for (thread = 0; thread < threads->nr; thread++) { - int fd; + int fd, group_fd; + + group_fd = get_group_fd(evsel, cpu, thread); fd = sys_perf_event_open(&evsel->attr, threads->map[thread].pid, - cpus->map[cpu], -1, 0); + cpus->map[cpu], group_fd, 0); if (fd < 0) return -errno; |