From 316a76a58c3f30735e5e416a6dc304d6bb86312d Mon Sep 17 00:00:00 2001 From: Thomas Richter Date: Mon, 17 May 2021 16:09:31 +0200 Subject: [PATCH] perf test: Fix libpfm4 support (63) test error for nested event groups Compiling perf with make LIBPFM4=1 includes libpfm support and enables test case 63 'Test libpfm4 support'. This test reports an error on all platforms for subtest 63.2 'test groups of --pfm-events'. The reported error message is 'nested event groups not supported' # ./perf test -F 63 63: Test libpfm4 support : 63.1: test of individual --pfm-events : Error: failed to parse event stereolab : event not found Error: failed to parse event stereolab,instructions : event not found Error: failed to parse event instructions,stereolab : event not found Ok 63.2: test groups of --pfm-events : Error: nested event groups not supported <------ Error message here Error: failed to parse event {stereolab} : event not found Error: failed to parse event {instructions,cycles},{instructions,stereolab} :\ event not found Ok # This patch addresses the error message 'nested event groups not supported'. The root cause is function parse_libpfm_events_option() which parses the event string '{},{instructions}' and can not handle a leading empty group notation '{},...'. The code detects the first (empty) group indicator '{' but does not terminate group processing on the following group closing character '}'. So when the second group indicator '{' is detected, the code assumes a nested group and returns an error. With the error message fixed, also change the expected event number to one for the test case to succeed. While at it also fix a memory leak. In good case the function does not free the duplicated string given as first parameter. Output after: # ./perf test -F 63 63: Test libpfm4 support : 63.1: test of individual --pfm-events : Error: failed to parse event stereolab : event not found Error: failed to parse event stereolab,instructions : event not found Error: failed to parse event instructions,stereolab : event not found Ok 63.2: test groups of --pfm-events : Error: failed to parse event {stereolab} : event not found Error: failed to parse event {instructions,cycles},{instructions,stereolab} : \ event not found Ok # Error message 'nested event groups not supported' is gone. Signed-off-by: Thomas Richter Acked-By: Ian Rogers Acked-by: Sumanth Korikkar Cc: Heiko Carstens Cc: Stephane Eranian Cc: Sven Schnelle Cc: Vasily Gorbik Link: http://lore.kernel.org/lkml/20210517140931.2559364-1-tmricht@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/tests/pfm.c | 4 ++-- tools/perf/util/pfm.c | 11 ++++++++++- 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/tools/perf/tests/pfm.c b/tools/perf/tests/pfm.c index 76a53126efdf..d4b0ef74defc 100644 --- a/tools/perf/tests/pfm.c +++ b/tools/perf/tests/pfm.c @@ -131,8 +131,8 @@ static int test__pfm_group(void) }, { .events = "{},{instructions}", - .nr_events = 0, - .nr_groups = 0, + .nr_events = 1, + .nr_groups = 1, }, { .events = "{instructions},{instructions}", diff --git a/tools/perf/util/pfm.c b/tools/perf/util/pfm.c index d735acb6c29c..6eef6dfeaa57 100644 --- a/tools/perf/util/pfm.c +++ b/tools/perf/util/pfm.c @@ -62,8 +62,16 @@ int parse_libpfm_events_option(const struct option *opt, const char *str, } /* no event */ - if (*q == '\0') + if (*q == '\0') { + if (*sep == '}') { + if (grp_evt < 0) { + ui__error("cannot close a non-existing event group\n"); + goto error; + } + grp_evt--; + } continue; + } memset(&attr, 0, sizeof(attr)); event_attr_init(&attr); @@ -107,6 +115,7 @@ int parse_libpfm_events_option(const struct option *opt, const char *str, grp_evt = -1; } } + free(p_orig); return 0; error: free(p_orig);