From: Namhyung Kim <namhyung@xxxxxxxxxx> Sometimes one can mistakenly run 'perf kmem stat' without running 'perf kmem record' before or with a different configuration like recording --slab and stat --page. Show a warning message like the one below to inform the user: # perf kmem stat --page --caller No page allocation events found. Have you run 'perf kmem record --page'? Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx> Acked-by: Pekka Enberg <penberg@xxxxxxxxxx> Cc: David Ahern <dsahern@xxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Joonsoo Kim <js1304@xxxxxxxxx> Cc: Minchan Kim <minchan@xxxxxxxxxx> Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: linux-mm@xxxxxxxxx Link: http://lkml.kernel.org/r/1430837572-31395-1-git-send-email-namhyung@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/perf/builtin-kmem.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c index 828b728..e628bf1 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[] = "No %s allocation events found. Have you run 'perf kmem record --%s'?\n"; perf_config(kmem_config, NULL); argc = parse_options_subcommand(argc, argv, kmem_options, @@ -1908,11 +1909,21 @@ int cmd_kmem(int argc, const char **argv, const char *prefix __maybe_unused) if (session == NULL) return -1; + if (kmem_slab) { + if (!perf_evlist__find_tracepoint_by_name(session->evlist, + "kmem:kmalloc")) { + pr_err(errmsg, "slab", "slab"); + return -1; + } + } + if (kmem_page) { - struct perf_evsel *evsel = perf_evlist__first(session->evlist); + struct perf_evsel *evsel; - if (evsel == NULL || evsel->tp_format == NULL) { - pr_err("invalid event found.. aborting\n"); + evsel = perf_evlist__find_tracepoint_by_name(session->evlist, + "kmem:mm_page_alloc"); + if (evsel == NULL) { + pr_err(errmsg, "page", "page"); return -1; } -- 2.1.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>