From patchwork Tue Jun 18 14:44:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Slavomir Kaslev X-Patchwork-Id: 11001919 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 97796924 for ; Tue, 18 Jun 2019 14:45:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 88BA82892E for ; Tue, 18 Jun 2019 14:45:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7D51428991; Tue, 18 Jun 2019 14:45:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 239492895F for ; Tue, 18 Jun 2019 14:45:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727105AbfFROpP (ORCPT ); Tue, 18 Jun 2019 10:45:15 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:46219 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729102AbfFROpO (ORCPT ); Tue, 18 Jun 2019 10:45:14 -0400 Received: by mail-wr1-f66.google.com with SMTP id n4so14272152wrw.13 for ; Tue, 18 Jun 2019 07:45:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=EXWmlzBvw3BAUKdyQKPZwLK9Y0qN0eFtSBA29XCQezA=; b=GWyabBVMeJvcaqglJx0DurnDEfB5+Eibl324hc/6x94zboKFxtyfBU30HnqBOSC9cu nJOwNKX5QiG7XMEUr+jBWf09fxXc11FreYnOlfcmwaGg6rtIjlUVaehfFHApPW0J00Yk sFhvT9NHpS5Yp/drW+Re1yUiVMotzdsjTlDhlLM9AHzji4Dd3S0FCIlGhEBxWspCDhu0 IPbOh2gjfriUd2qbaCtIXI4BZYvmg6OnQ5wDZ/OmJqVzgr/6W0xQRQ8Xb2DV7kapzBk9 vsvr9WGZRCWEItSIFRk4pxRHrMKhVJQdOJ8jPDJbc8mPGWuy8/VHs872L1NPtp+R5ZE3 hPgA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=EXWmlzBvw3BAUKdyQKPZwLK9Y0qN0eFtSBA29XCQezA=; b=VQ1bDNGoF6fmaWa13+eQd6t5EH/pNuML0CXmv397kI3BQ6Yu/lkAwyGsGgG3aAwKes 95Thkdc7jbCNzpN5asenWM3HKnfeez/o4/C+Fs1ofkI2J0YclWaCdo/SsQZKYIwWa8kw wkGhStBtZ+51kbGhyBm6k28VJ5plvf0Q7noV6y6eHKIa8ynFleX5Dtu0CSjMizI4AiEx j8ruOrQwTxjgADDxu/RIXvC0Nh9BSgdqvG12D5yq3jkKRNx2qJIRZQXKhn3wabePy2ts OzhHSd/Tflv/5I4d3DYFZbeDbUjxIq8AoEWZh/7g7DxPw29t2ng//JDu+seH+f82cTFr r7Ig== X-Gm-Message-State: APjAAAXYggGjg4QDmduxKPgrRWokztuZv1yS3PqkGyZdBqjZqReHLzFK A151cULu7akVX1SGpd679A== X-Google-Smtp-Source: APXvYqyaZuLiZkfhecVY4pSQq7a1F+SkkS9xBJzoIZJTtoz7RUEAj8H74A6874wWrpuTKKt9FcfBtA== X-Received: by 2002:a5d:53c2:: with SMTP id a2mr29938829wrw.8.1560869112468; Tue, 18 Jun 2019 07:45:12 -0700 (PDT) Received: from box.eng.vmware.com ([146.247.46.5]) by smtp.gmail.com with ESMTPSA id r3sm17686071wrr.61.2019.06.18.07.45.11 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Tue, 18 Jun 2019 07:45:11 -0700 (PDT) From: "Slavomir Kaslev (VMware)" To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org Subject: [PATCH v12 10/13] trace-cmd: Try to autodetect number of guest CPUs in setup-guest if not specified Date: Tue, 18 Jun 2019 17:44:52 +0300 Message-Id: <20190618144455.3954-11-slavomir.kaslev@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190618144455.3954-1-slavomir.kaslev@gmail.com> References: <20190618144455.3954-1-slavomir.kaslev@gmail.com> MIME-Version: 1.0 Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Slavomir Kaslev When no number of guest CPUs is provided with the -c flag to `trace-cmd setup-guest`, try to autodetect it using virsh for libvirt managed guests. Signed-off-by: Slavomir Kaslev --- tracecmd/trace-setup-guest.c | 21 +++++++++++++++++++++ tracecmd/trace-usage.c | 2 +- 2 files changed, 22 insertions(+), 1 deletion(-) diff --git a/tracecmd/trace-setup-guest.c b/tracecmd/trace-setup-guest.c index a6f58dc..a55a37d 100644 --- a/tracecmd/trace-setup-guest.c +++ b/tracecmd/trace-setup-guest.c @@ -93,6 +93,24 @@ static int make_guest_fifos(const char *guest, int nr_cpus, mode_t mode) return ret; } +static int get_guest_cpu_count(const char *guest) +{ + const char *cmd_fmt = "virsh vcpucount --maximum '%s' 2>/dev/null"; + int nr_cpus = -1; + char cmd[1024]; + FILE *f; + + snprintf(cmd, sizeof(cmd), cmd_fmt, guest); + f = popen(cmd, "r"); + if (!f) + return -errno; + + fscanf(f, "%d", &nr_cpus); + pclose(f); + + return nr_cpus; +} + static void do_setup_guest(const char *guest, int nr_cpus, mode_t mode, gid_t gid) { gid_t save_egid; @@ -171,6 +189,9 @@ void trace_setup_guest(int argc, char **argv) guest = argv[optind+1]; + if (nr_cpus <= 0) + nr_cpus = get_guest_cpu_count(guest); + if (nr_cpus <= 0) pdie("invalid number of cpus for guest %s", guest); diff --git a/tracecmd/trace-usage.c b/tracecmd/trace-usage.c index 0d1b58e..a2a520c 100644 --- a/tracecmd/trace-usage.c +++ b/tracecmd/trace-usage.c @@ -251,7 +251,7 @@ static struct usage_help usage_help[] = { { "setup-guest", "create FIFOs for tracing guest VMs", - " %s setup-guest -c cpus[-p perm][-g group] guest\n" + " %s setup-guest [-c cpus][-p perm][-g group] guest\n" " -c number of guest virtual CPUs\n" " -p FIFOs permissions (default: 0660)\n" " -g FIFOs group owner\n"