From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Olsa Subject: Re: [PATCH 05/12] perf pmu: Fix pmu events parsing rule Date: Thu, 3 May 2018 13:47:38 +0200 Message-ID: <20180503114738.GB14776@krava> References: <20180425160008.3407-1-acme@kernel.org> <20180425160008.3407-6-acme@kernel.org> <448c4e21-8232-3d04-cac4-49b95c8bca3a@intel.com> <20180503103717.GA14776@krava> <0c33d3f9-4b76-c94c-7306-e93e8cd8d4aa@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <0c33d3f9-4b76-c94c-7306-e93e8cd8d4aa@intel.com> Sender: linux-kernel-owner@vger.kernel.org To: Adrian Hunter Cc: Arnaldo Carvalho de Melo , Ingo Molnar , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Jiri Olsa , Alexander Shishkin , David Ahern , Namhyung Kim , Peter Zijlstra , Arnaldo Carvalho de Melo List-Id: linux-perf-users.vger.kernel.org On Thu, May 03, 2018 at 02:38:15PM +0300, Adrian Hunter wrote: > On 03/05/18 13:37, Jiri Olsa wrote: > > On Thu, May 03, 2018 at 11:25:16AM +0300, Adrian Hunter wrote: > >> Hi > >> > >> This breaks Intel PT i.e. > >> > >> $ perf record -e intel_pt//u uname > >> event syntax error: 'intel_pt//u' > >> \___ parser error > >> Run 'perf list' for a list of valid events > >> > >> Usage: perf record [] [] > >> or: perf record [] -- [] > >> > >> -e, --event event selector. use 'perf list' to list available events > >> > >> See below for cause. > >> > >> On 25/04/18 19:00, Arnaldo Carvalho de Melo wrote: > >>> From: Jiri Olsa > >>> > >>> Currently all the event parsing fails end up in the event_pmu rule, and > >>> display misleading help like: > >>> > >>> $ perf stat -e inst kill > >>> event syntax error: 'inst' > >>> \___ Cannot find PMU `inst'. Missing kernel support? > >>> ... > >>> > >>> The reason is that the event_pmu is too strong and match also single > >>> string. Changing it to force the '/' separators to be part of the rule, > >>> and getting the proper error now: > >>> > >>> $ perf stat -e inst kill > >>> event syntax error: 'inst' > >>> \___ parser error > >>> Run 'perf list' for a list of valid events > >>> ... > >>> > >>> Signed-off-by: Jiri Olsa > >>> Reported-by: Ingo Molnar > >>> Tested-by: Arnaldo Carvalho de Melo > >>> Cc: Alexander Shishkin > >>> Cc: David Ahern > >>> Cc: Namhyung Kim > >>> Cc: Peter Zijlstra > >>> Link: http://lkml.kernel.org/r/20180423090823.32309-5-jolsa@kernel.org > >>> Signed-off-by: Arnaldo Carvalho de Melo > >>> --- > >>> tools/perf/util/parse-events.y | 8 ++++---- > >>> 1 file changed, 4 insertions(+), 4 deletions(-) > >>> > >>> diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y > >>> index 7afeb80cc39e..d14464c42714 100644 > >>> --- a/tools/perf/util/parse-events.y > >>> +++ b/tools/perf/util/parse-events.y > >>> @@ -224,15 +224,15 @@ event_def: event_pmu | > >>> event_bpf_file > >>> > >>> event_pmu: > >>> -PE_NAME opt_event_config > >>> +PE_NAME '/' event_config '/' > >> > >> These are not equivalent because opt_event_config allows '//' > >> but event_config cannot be an empty string. > > > > yep, overlooked this one, how about patch below > > Seems to work but gives build warnings: > > util/parse-events.y: warning: 1 shift/reduce conflict [-Wconflicts-sr] > util/parse-events.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr] hm, I wonder why my bison was silent.. there's conflict with opt_event_config reduction to empty, I'll resend thanks, jirka