On Mon, 22 Mar 2021 11:59:28 +0200 "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@xxxxxxxxx> wrote: > +void trace_perf_close(struct trace_perf *perf) > +{ > + if (perf->fd >= 0) > + close(perf->fd); > + perf->fd = -1; > + if (perf->mmap) The above should be: if (perf->mmap && perf->mmap != MAP_FAILED) -- Steve > + munmap(perf->mmap, (perf->pages + 1) * getpagesize()); > + perf->mmap = NULL; > +} > + > +/** > + * trace_perf_open - Open perf session > + * > + * @perf: structure, representing perf context that will be opened. It must be > + * initialized with trace_perf_init(). > + * > + * Returns 0 on success, or -1 in case of an error. In case of success, the > + * session must be closed with trace_perf_close() > + */ > +int trace_perf_open(struct trace_perf *perf) > +{ > + perf->fd = syscall(__NR_perf_event_open, &perf->pe, perf->pid, perf->cpu, -1, 0); > + if (perf->fd < 0) > + return -1; > + fcntl(perf->fd, F_SETFL, O_NONBLOCK); > + > + perf->mmap = mmap(NULL, (perf->pages + 1) * getpagesize(), > + PROT_READ | PROT_WRITE, MAP_SHARED, perf->fd, 0); > + if (perf->mmap == MAP_FAILED) > + goto error; > + > + return 0; > + > +error: > + trace_perf_close(perf); > + return -1; > +}