From patchwork Tue Aug 3 04:23:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 12415181 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 891BAC432BE for ; Tue, 3 Aug 2021 04:24:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 714BF61158 for ; Tue, 3 Aug 2021 04:24:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233854AbhHCEYV (ORCPT ); Tue, 3 Aug 2021 00:24:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:57234 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233719AbhHCEYI (ORCPT ); Tue, 3 Aug 2021 00:24:08 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4DEAD611C2; Tue, 3 Aug 2021 04:23:57 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94.2) (envelope-from ) id 1mAly8-002qnv-6k; Tue, 03 Aug 2021 00:23:56 -0400 From: Steven Rostedt To: linux-trace-devel@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Tom Zanussi , Daniel Bristot de Oliveira , Masami Hiramatsu , Namhyung Kim , linux-rt-users , Clark Williams , "Steven Rostedt (VMware)" Subject: [PATCH v2 19/21] libtracefs: Allow trace_sql() to take keywords for fields with backslash Date: Tue, 3 Aug 2021 00:23:45 -0400 Message-Id: <20210803042347.679499-20-rostedt@goodmis.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210803042347.679499-1-rostedt@goodmis.org> References: <20210803042347.679499-1-rostedt@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org From: "Steven Rostedt (VMware)" Some events have fields with keywords, and the parsing will not let it work. For example, you can have: select from from regcache_drop_region And that will produce a syntax error, as the from will confuse the parser. Allow fields to start with a backslash, which will allow the parser to see "from" as a field and not as a keyword. That is: select \from from regcache_drop_region will work as expected. Note, any field can start with a backslash, and the starting backslash will be ignored. Signed-off-by: Steven Rostedt (VMware) --- Documentation/libtracefs-sql.txt | 20 ++++++++++++++++++++ src/sqlhist.l | 6 ++++-- 2 files changed, 24 insertions(+), 2 deletions(-) diff --git a/Documentation/libtracefs-sql.txt b/Documentation/libtracefs-sql.txt index 190abe641d7c..e38ed7649432 100644 --- a/Documentation/libtracefs-sql.txt +++ b/Documentation/libtracefs-sql.txt @@ -162,6 +162,26 @@ select start.pid, (end.TIMESTAMP_USECS - start.TIMESTAMP_USECS) as lat from sche WHERE start.prio < 100 || end.prev_prio < 100 -- + +KEYWORDS AS EVENT FIELDS +------------------------ + +In some cases, an event may have a keyword. For example, regcache_drop_region has "from" +as a field and the following will not work + +[source,c] +-- + select from from regcache_drop_region +-- + +In such cases, add a backslash to the conflicting field, and this will tell the parser +that the "from" is a field and not a keyword: + +[source,c] +-- + select \from from regcache_drop_region +-- + HISTOGRAMS ---------- diff --git a/src/sqlhist.l b/src/sqlhist.l index f9e0fcc17e63..897daac7d2a8 100644 --- a/src/sqlhist.l +++ b/src/sqlhist.l @@ -25,7 +25,7 @@ extern int my_yyinput(void *extra, char *buf, int max); %option reentrant %option bison-bridge -field [a-z_][a-z0-9_\.]* +field \\?[a-z_][a-z0-9_\.]* qstring \"[^\"]*\" hexnum 0x[0-9a-f]+ number [0-9a-f]+ @@ -46,8 +46,10 @@ where { HANDLE_COLUMN; return WHERE; } } {field} { + const char *str = yyg->yytext_r; HANDLE_COLUMN; - yylval->string = store_str(TRACE_SB, yyg->yytext_r); + if (str[0] == '\\') { str++; }; + yylval->string = store_str(TRACE_SB, str); return FIELD; }