From mboxrd@z Thu Jan 1 00:00:00 1970 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=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 63C4CC433FE for ; Thu, 10 Dec 2020 18:08:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0069923C44 for ; Thu, 10 Dec 2020 18:08:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404102AbgLJSIg (ORCPT ); Thu, 10 Dec 2020 13:08:36 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:30012 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392845AbgLJSIX (ORCPT ); Thu, 10 Dec 2020 13:08:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1607623616; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=vzwpL+oyCC6ybTYdSfCdXZ5JS1M9p4/+mGraiaF/j9s=; b=a7FGgSxWNpoJVrX5jNakOgvBwOMumYhWXWN9PQkqI3ufHTSTubaQYGST/wCVYine2fMn9R P2lZU6CuART6L/C0X543ewI78ppFF/ZfTm+osoq+uyV1DzICYnbIiRYKWLYiIxiR61s9rU 517NislATGmEtYr4AKalzFczMpMcGTA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-215-CraozjSoN-ChzJf9f-h3Pg-1; Thu, 10 Dec 2020 13:06:52 -0500 X-MC-Unique: CraozjSoN-ChzJf9f-h3Pg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3158B84A5EC; Thu, 10 Dec 2020 18:06:50 +0000 (UTC) Received: from krava (unknown [10.40.192.193]) by smtp.corp.redhat.com (Postfix) with SMTP id 1041F5F9B8; Thu, 10 Dec 2020 18:06:46 +0000 (UTC) Date: Thu, 10 Dec 2020 19:06:46 +0100 From: Jiri Olsa To: Alexei Budankov Cc: Jiri Olsa , Arnaldo Carvalho de Melo , lkml , Peter Zijlstra , Ingo Molnar , Mark Rutland , Namhyung Kim , Alexander Shishkin , Michael Petlan , Ian Rogers , Stephane Eranian Subject: Re: [PATCH 2/3] perf tools: Allow to enable/disable events via control file Message-ID: <20201210180646.GA186916@krava> References: <20201206170519.4010606-1-jolsa@kernel.org> <20201206170519.4010606-3-jolsa@kernel.org> <7bcde520-e933-c2d6-c960-3f8acdaf6047@huawei.com> <20201210162430.GH69683@krava> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201210162430.GH69683@krava> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 10, 2020 at 05:24:30PM +0100, Jiri Olsa wrote: > On Mon, Dec 07, 2020 at 08:02:20PM +0300, Alexei Budankov wrote: > > Hi, > > > > On 06.12.2020 20:05, Jiri Olsa wrote: > > > Adding new control events to enable/disable specific event. > > > The interface string for control file are: > > > > > > 'enable-' > > > 'disable-' > > > > > > > > > > > > when received the command, perf will scan the current evlist > > > for and if found it's enabled/disabled. > > > > > > > > > diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c > > > index 70aff26612a9..05723227bebf 100644 > > > --- a/tools/perf/util/evlist.c > > > +++ b/tools/perf/util/evlist.c > > > @@ -1915,7 +1915,13 @@ static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd, > > > bytes_read == data_size ? "" : c == '\n' ? "\\n" : "\\0"); > > > > > > if (bytes_read > 0) { > > > - if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_TAG, > > > + if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_EVSEL_TAG, > > > + (sizeof(EVLIST_CTL_CMD_ENABLE_EVSEL_TAG)-1))) { > > > + *cmd = EVLIST_CTL_CMD_ENABLE_EVSEL; > > > + } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_DISABLE_EVSEL_TAG, > > > + (sizeof(EVLIST_CTL_CMD_DISABLE_EVSEL_TAG)-1))) { > > > + *cmd = EVLIST_CTL_CMD_DISABLE_EVSEL; > > > + } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_TAG, > > > (sizeof(EVLIST_CTL_CMD_ENABLE_TAG)-1))) { > > > *cmd = EVLIST_CTL_CMD_ENABLE; > > > } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_DISABLE_TAG, > > > @@ -1952,6 +1958,8 @@ int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd) > > > char cmd_data[EVLIST_CTL_CMD_MAX_LEN]; > > > int ctlfd_pos = evlist->ctl_fd.pos; > > > struct pollfd *entries = evlist->core.pollfd.entries; > > > + struct evsel *evsel; > > > + char *evsel_name; > > > > > > if (!evlist__ctlfd_initialized(evlist) || !entries[ctlfd_pos].revents) > > > return 0; > > > @@ -1967,6 +1975,26 @@ int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd) > > > case EVLIST_CTL_CMD_DISABLE: > > > evlist__disable(evlist); > > > break; > > > + case EVLIST_CTL_CMD_ENABLE_EVSEL: > > > + evsel_name = cmd_data + sizeof(EVLIST_CTL_CMD_ENABLE_EVSEL_TAG) - 1; > > > > It makes sense to check that evsel_name still points > > into cmd_data buffer after assigning to event name. > > right, will add that actualy it's already checked in evlist__ctlfd_recv, evsel_name at worst will be empty string so evlist__find_evsel_by_str will fail I'll add '' around %s in the error output string: failed: can't find '%s' event so it's obvious when it's empty jirka