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Possible processes: 55683 ./perf stat -e intel_pt// ``` Only perf with intel_pt was reported. Signed-off-by: Chun-Tse Shao --- tools/perf/util/evsel.c | 79 +++++++++++++++++++++++++++++------------ 1 file changed, 57 insertions(+), 22 deletions(-) diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 9a5b6a6f8d2e5..d2f7c19e023ec 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -3286,7 +3286,8 @@ static bool find_process(const char *name) return ret ? false : true; } -static int dump_perf_event_processes(char *msg, size_t size) +static int dump_perf_event_processes(const struct perf_event_attr *failed_attr, + char *msg, size_t size) { DIR *proc_dir; struct dirent *proc_entry; @@ -3327,29 +3328,61 @@ static int dump_perf_event_processes(char *msg, size_t size) continue; /* Take care as readlink doesn't null terminate the string. */ if (!strncmp(path, "anon_inode:[perf_event]", link_size)) { - int cmdline_fd; - ssize_t cmdline_size; - - scnprintf(path, sizeof(path), "%s/cmdline", proc_entry->d_name); - cmdline_fd = openat(dirfd(proc_dir), path, O_RDONLY); - if (cmdline_fd == -1) - continue; - cmdline_size = read(cmdline_fd, path, sizeof(path) - 1); - close(cmdline_fd); - if (cmdline_size < 0) + int fdinfo_fd; + ssize_t fdinfo_size; + char *line; + u32 perf_event_type = PERF_TYPE_MAX; + + /* Let's check the PMU type reserved by this process */ + scnprintf(path, sizeof(path), "%s/fdinfo/%s", + proc_entry->d_name, fd_entry->d_name); + fdinfo_fd = openat(dirfd(proc_dir), path, O_RDONLY); + fdinfo_size = read(fdinfo_fd, path, sizeof(path) - 1); + if (fdinfo_size < 0) continue; - path[cmdline_size] = '\0'; - for (ssize_t i = 0; i < cmdline_size; i++) { - if (path[i] == '\0') - path[i] = ' '; + path[fdinfo_size] = '\0'; + + line = strtok(path, "\n"); + while (line != NULL) { + if (sscanf(line, + "perf_event-attr.type:\t%u", + &perf_event_type) == 1) + break; + line = strtok(NULL, "\n"); } - if (printed == 0) - printed += scnprintf(msg, size, "Possible processes:\n"); - - printed += scnprintf(msg + printed, size - printed, - "%s %s\n", proc_entry->d_name, path); - break; + /* Report the process which reserves the conflicted PMU. */ + /* If fdinfo does not contain PMU type, report it too. */ + if (perf_event_type == failed_attr->type || + perf_event_type == PERF_TYPE_MAX) { + int cmdline_fd; + ssize_t cmdline_size; + + scnprintf(path, sizeof(path), + "%s/cmdline", + proc_entry->d_name); + cmdline_fd = openat(dirfd(proc_dir), path, O_RDONLY); + if (cmdline_fd == -1) + continue; + cmdline_size = read(cmdline_fd, path, sizeof(path) - 1); + close(cmdline_fd); + if (cmdline_size < 0) + continue; + path[cmdline_size] = '\0'; + for (ssize_t i = 0; i < cmdline_size; i++) { + if (path[i] == '\0') + path[i] = ' '; + } + + if (printed == 0) + printed += scnprintf( + msg, size, + "Possible processes:\n"); + + printed += scnprintf(msg + printed, size - printed, + "%s %s\n", proc_entry->d_name, path); + break; + } } } closedir(fd_dir); @@ -3458,7 +3491,9 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target, msg, size, "The PMU %s counters are busy and in use by another process.\n", evsel->pmu ? evsel->pmu->name : ""); - return printed + dump_perf_event_processes(msg + printed, size - printed); + return printed + dump_perf_event_processes(&evsel->core.attr, + msg + printed, + size - printed); break; case EINVAL: if (evsel->core.attr.sample_type & PERF_SAMPLE_CODE_PAGE_SIZE && perf_missing_features.code_page_size) -- 2.47.0.163.g1226f6d8fa-goog