From patchwork Mon Feb 21 22:16:54 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Bristot de Oliveira X-Patchwork-Id: 12754211 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CC225C433F5 for ; Mon, 21 Feb 2022 22:18:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235556AbiBUWSX convert rfc822-to-8bit (ORCPT ); Mon, 21 Feb 2022 17:18:23 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:40476 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235547AbiBUWSV (ORCPT ); Mon, 21 Feb 2022 17:18:21 -0500 Received: from us-smtp-delivery-44.mimecast.com (us-smtp-delivery-44.mimecast.com [205.139.111.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id D81E624093 for ; Mon, 21 Feb 2022 14:17:44 -0800 (PST) Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-612-fA0w9ciIPpCuAggYa31MgA-1; Mon, 21 Feb 2022 17:17:38 -0500 X-MC-Unique: fA0w9ciIPpCuAggYa31MgA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 773971DDE9; Mon, 21 Feb 2022 22:17:37 +0000 (UTC) Received: from x1.com (unknown [10.22.16.159]) by smtp.corp.redhat.com (Postfix) with ESMTP id CAB335DB8F; Mon, 21 Feb 2022 22:17:34 +0000 (UTC) From: Daniel Bristot de Oliveira To: Steven Rostedt Cc: Daniel Bristot de Oliveira , Jonathan Corbet , Clark Williams , Juri Lelli , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-devel@vger.kernel.org Subject: [PATCH V2 09/11] rtla/trace: Add trace event filter helpers Date: Mon, 21 Feb 2022 23:16:54 +0100 Message-Id: <8846cb46f9b4277b44e523881bbcd0e6b7f31e91.1645481500.git.bristot@kernel.org> In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=bristot@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org Add a set of helper functions to allow rtla tools to filter events in the trace instance. Cc: Daniel Bristot de Oliveira Cc: Steven Rostedt Cc: Jonathan Corbet Signed-off-by: Daniel Bristot de Oliveira --- tools/tracing/rtla/src/trace.c | 83 ++++++++++++++++++++++++++++++++++ tools/tracing/rtla/src/trace.h | 3 ++ 2 files changed, 86 insertions(+) diff --git a/tools/tracing/rtla/src/trace.c b/tools/tracing/rtla/src/trace.c index 7f8661b2724d..ef44bab0c404 100644 --- a/tools/tracing/rtla/src/trace.c +++ b/tools/tracing/rtla/src/trace.c @@ -204,6 +204,8 @@ static void trace_events_free(struct trace_events *events) tevent = tevent->next; + if (free_event->filter) + free(free_event->filter); if (free_event->trigger) free(free_event->trigger); free(free_event->system); @@ -237,6 +239,21 @@ struct trace_events *trace_event_alloc(const char *event_string) return tevent; } +/* + * trace_event_add_filter - record an event filter + */ +int trace_event_add_filter(struct trace_events *event, char *filter) +{ + if (event->filter) + free(event->filter); + + event->filter = strdup(filter); + if (!event->filter) + return 1; + + return 0; +} + /* * trace_event_add_trigger - record an event trigger action */ @@ -252,6 +269,33 @@ int trace_event_add_trigger(struct trace_events *event, char *trigger) return 0; } +/* + * trace_event_disable_filter - disable an event filter + */ +static void trace_event_disable_filter(struct trace_instance *instance, + struct trace_events *tevent) +{ + char filter[1024]; + int retval; + + if (!tevent->filter) + return; + + if (!tevent->filter_enabled) + return; + + debug_msg("Disabling %s:%s filter %s\n", tevent->system, + tevent->event ? : "*", tevent->filter); + + snprintf(filter, 1024, "!%s\n", tevent->filter); + + retval = tracefs_event_file_write(instance->inst, tevent->system, + tevent->event, "filter", filter); + if (retval < 0) + err_msg("Error disabling %s:%s filter %s\n", tevent->system, + tevent->event ? : "*", tevent->filter); +} + /* * trace_event_disable_trigger - disable an event trigger */ @@ -293,6 +337,7 @@ void trace_events_disable(struct trace_instance *instance, while (tevent) { debug_msg("Disabling event %s:%s\n", tevent->system, tevent->event ? : "*"); if (tevent->enabled) { + trace_event_disable_filter(instance, tevent); trace_event_disable_trigger(instance, tevent); tracefs_event_disable(instance->inst, tevent->system, tevent->event); } @@ -302,6 +347,41 @@ void trace_events_disable(struct trace_instance *instance, } } +/* + * trace_event_enable_filter - enable an event filter associated with an event + */ +static int trace_event_enable_filter(struct trace_instance *instance, + struct trace_events *tevent) +{ + char filter[1024]; + int retval; + + if (!tevent->filter) + return 0; + + if (!tevent->event) { + err_msg("Filter %s applies only for single events, not for all %s:* events\n", + tevent->filter, tevent->system); + return 1; + } + + snprintf(filter, 1024, "%s\n", tevent->filter); + + debug_msg("Enabling %s:%s filter %s\n", tevent->system, + tevent->event ? : "*", tevent->filter); + + retval = tracefs_event_file_write(instance->inst, tevent->system, + tevent->event, "filter", filter); + if (retval < 0) { + err_msg("Error enabling %s:%s filter %s\n", tevent->system, + tevent->event ? : "*", tevent->filter); + return 1; + } + + tevent->filter_enabled = 1; + return 0; +} + /* * trace_event_enable_trigger - enable an event trigger associated with an event */ @@ -356,6 +436,9 @@ int trace_events_enable(struct trace_instance *instance, return 1; } + retval = trace_event_enable_filter(instance, tevent); + if (retval) + return 1; retval = trace_event_enable_trigger(instance, tevent); if (retval) diff --git a/tools/tracing/rtla/src/trace.h b/tools/tracing/rtla/src/trace.h index 856b26d93064..51ad344c600b 100644 --- a/tools/tracing/rtla/src/trace.h +++ b/tools/tracing/rtla/src/trace.h @@ -6,8 +6,10 @@ struct trace_events { struct trace_events *next; char *system; char *event; + char *filter; char *trigger; char enabled; + char filter_enabled; char trigger_enabled; }; @@ -43,4 +45,5 @@ void trace_events_destroy(struct trace_instance *instance, int trace_events_enable(struct trace_instance *instance, struct trace_events *events); +int trace_event_add_filter(struct trace_events *event, char *filter); int trace_event_add_trigger(struct trace_events *event, char *trigger);