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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 AD304C282DD for ; Wed, 8 Jan 2020 22:22:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 74D6620692 for ; Wed, 8 Jan 2020 22:22:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="F3GBkOhd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727225AbgAHWWK (ORCPT ); Wed, 8 Jan 2020 17:22:10 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:44884 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726548AbgAHWWJ (ORCPT ); Wed, 8 Jan 2020 17:22:09 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1578522126; 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=YFgWeK11XCYWDQjlF9XC3VqlDhhZtHK2pS8IpXWNa9M=; b=F3GBkOhd94htkUPL1/1XO1+LV26FvdEAcEvwRVNyAHkAaYvMBI/LWW8O/mTgifKUk+yPvE xQ5NSx1v0sTtQJO7x6n1ADZpmOVsxJgcCdFn5LS7aToh5e61aWGjVi2bAj2q+OKEO5Rzba i4ra8xduhIsy4aCLCvYEgl5ljGlEhek= 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-385-nl0AHG0LPZWsVohSJpqLgA-1; Wed, 08 Jan 2020 17:22:03 -0500 X-MC-Unique: nl0AHG0LPZWsVohSJpqLgA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 23E06800D4E; Wed, 8 Jan 2020 22:22:01 +0000 (UTC) Received: from krava (ovpn-204-121.brq.redhat.com [10.40.204.121]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D2D1760F82; Wed, 8 Jan 2020 22:21:58 +0000 (UTC) Date: Wed, 8 Jan 2020 23:21:56 +0100 From: Jiri Olsa To: Namhyung Kim Cc: Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Alexander Shishkin , Mark Rutland , Stephane Eranian , LKML , linux-perf-users@vger.kernel.org Subject: Re: [PATCH 6/9] perf record: Support synthesizing cgroup events Message-ID: <20200108222156.GE12995@krava> References: <20200107133501.327117-1-namhyung@kernel.org> <20200107133501.327117-7-namhyung@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200107133501.327117-7-namhyung@kernel.org> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 07, 2020 at 10:34:58PM +0900, Namhyung Kim wrote: SNIP > + closedir(d); > + return ret; > +} > + > +int perf_event__synthesize_cgroups(struct perf_tool *tool, > + perf_event__handler_t process, > + struct machine *machine) > +{ > + union perf_event event; > + char *cgrp_root; > + size_t mount_len; /* length of mount point in the path */ > + int ret = -1; > + > + cgrp_root = malloc(PATH_MAX); > + if (cgrp_root == NULL) > + return -1; > + hum, we normally use bufs with PATH_MAX size on stack.. is there some reason to use heap in here? jirka > + if (cgroupfs_find_mountpoint(cgrp_root, PATH_MAX) < 0) { > + pr_debug("cannot find cgroup mount point\n"); > + goto out; > + } > + > + mount_len = strlen(cgrp_root); > + /* make sure the path starts with a slash (after mount point) */ > + strcat(cgrp_root, "/"); > + > + if (perf_event__walk_cgroup_tree(tool, &event, cgrp_root, mount_len, > + process, machine) < 0) > + goto out; > + > + ret = 0; > + > +out: > + free(cgrp_root); > + > + return ret; > +} > + SNIP