From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753832AbdHKX0n (ORCPT ); Fri, 11 Aug 2017 19:26:43 -0400 Received: from mga09.intel.com ([134.134.136.24]:25982 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753127AbdHKX0k (ORCPT ); Fri, 11 Aug 2017 19:26:40 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.41,360,1498546800"; d="scan'208";a="118177246" From: Andi Kleen To: acme@kernel.org Cc: jolsa@kernel.org, linux-kernel@vger.kernel.org, Andi Kleen Subject: [PATCH v2 04/19] perf, tools: Tighten detection of BPF events Date: Fri, 11 Aug 2017 16:26:19 -0700 Message-Id: <20170811232634.30465-4-andi@firstfloor.org> X-Mailer: git-send-email 2.9.4 In-Reply-To: <20170811232634.30465-1-andi@firstfloor.org> References: <20170811232634.30465-1-andi@firstfloor.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andi Kleen perf stat -e cpu/uops_executed.core,cmask=1/ would be detected as a BPF source event because the .c matches the .c source BPF pattern. v2: Originally I tried to use lex lookahead, but it doesn't seem to work. This now extends the BPF pattern to match longer events, but then does an extra check in the C code to reject BPF matches that do not end with .c/.o/.obj This uses REJECT, which makes the flex scanner slower, but that shouldn't be a big problem for the perf events. Signed-off-by: Andi Kleen --- tools/perf/util/parse-events.l | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l index 660fca05bc93..c42edeac451f 100644 --- a/tools/perf/util/parse-events.l +++ b/tools/perf/util/parse-events.l @@ -53,6 +53,21 @@ static int str(yyscan_t scanner, int token) return token; } +static bool isbpf(yyscan_t scanner) +{ + char *text = parse_events_get_text(scanner); + int len = strlen(text); + + if (len < 2) + return false; + if ((text[len - 1] == 'c' || text[len - 1] == 'o') && + text[len - 2] == '.') + return true; + if (len > 4 && !strcmp(text + len - 4, ".obj")) + return true; + return false; +} + /* * This function is called when the parser gets two kind of input: * @@ -136,8 +151,8 @@ do { \ group [^,{}/]*[{][^}]*[}][^,{}/]* event_pmu [^,{}/]+[/][^/]*[/][^,{}/]* event [^,{}/]+ -bpf_object [^,{}]+\.(o|bpf) -bpf_source [^,{}]+\.c +bpf_object [^,{}]+\.(o|bpf)[a-zA-Z0-9._]* +bpf_source [^,{}]+\.c[a-zA-Z0-9._]* num_dec [0-9]+ num_hex 0x[a-fA-F0-9]+ @@ -307,8 +322,8 @@ r{num_raw_hex} { return raw(yyscanner); } {num_hex} { return value(yyscanner, 16); } {modifier_event} { return str(yyscanner, PE_MODIFIER_EVENT); } -{bpf_object} { return str(yyscanner, PE_BPF_OBJECT); } -{bpf_source} { return str(yyscanner, PE_BPF_SOURCE); } +{bpf_object} { if (!isbpf(yyscanner)) REJECT; return str(yyscanner, PE_BPF_OBJECT); } +{bpf_source} { if (!isbpf(yyscanner)) REJECT; return str(yyscanner, PE_BPF_SOURCE); } {name} { return pmu_str_check(yyscanner); } "/" { BEGIN(config); return '/'; } - { return '-'; } -- 2.9.4