Sometimes one can mistakenly run perf kmem stat without perf kmem record before or different configuration like recoding --slab and stat --page. Show a warning message like below to inform user:
# perf kmem stat --page --caller Not found page events. Have you run 'perf kmem record --page' before? Signed-off-by: Namhyung Kim <namhy...@kernel.org> --- tools/perf/builtin-kmem.c | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c index f0d018179e1c..ddb6ccb88b45 100644 --- a/tools/perf/builtin-kmem.c +++ b/tools/perf/builtin-kmem.c @@ -1882,6 +1882,7 @@ int cmd_kmem(int argc, const char **argv, const char *prefix __maybe_unused) }; struct perf_session *session; int ret = -1; + const char errmsg[] = "Not found %s events. Have you run 'perf kmem record --%s' before?\n"; perf_config(kmem_config, NULL); argc = parse_options_subcommand(argc, argv, kmem_options, @@ -1908,11 +1909,35 @@ int cmd_kmem(int argc, const char **argv, const char *prefix __maybe_unused) if (session == NULL) return -1; + if (kmem_slab) { + struct perf_evsel *evsel; + bool found = false; + + evlist__for_each(session->evlist, evsel) { + if (!strcmp(perf_evsel__name(evsel), "kmem:kmalloc")) { + found = true; + break; + } + } + if (!found) { + pr_err(errmsg, "slab", "slab"); + return -1; + } + } + if (kmem_page) { - struct perf_evsel *evsel = perf_evlist__first(session->evlist); + struct perf_evsel *evsel; + bool found = false; - if (evsel == NULL || evsel->tp_format == NULL) { - pr_err("invalid event found.. aborting\n"); + evlist__for_each(session->evlist, evsel) { + if (!strcmp(perf_evsel__name(evsel), + "kmem:mm_page_alloc")) { + found = true; + break; + } + } + if (!found) { + pr_err(errmsg, "page", "page"); return -1; } -- 2.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/