diff options
Diffstat (limited to 'tools/lib/perf/evsel.c')
| -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; |