From patchwork Wed Jun 26 10:52:06 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Slavomir Kaslev X-Patchwork-Id: 11017453 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 8924813B4 for ; Wed, 26 Jun 2019 10:52:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 77962285C9 for ; Wed, 26 Jun 2019 10:52:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6AA0428741; Wed, 26 Jun 2019 10:52:29 +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 12731285C9 for ; Wed, 26 Jun 2019 10:52:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727114AbfFZKw2 (ORCPT ); Wed, 26 Jun 2019 06:52:28 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:33616 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726772AbfFZKw2 (ORCPT ); Wed, 26 Jun 2019 06:52:28 -0400 Received: by mail-wr1-f65.google.com with SMTP id n9so2213993wru.0 for ; Wed, 26 Jun 2019 03:52:27 -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=pdbEqjo85GFvpuYA+qX4eyM9THFqXnSndo1krjcK/c1YrENYas1kEWmTFE8WhcNPbZ HtOspXiqZhAJtqt5l77qE46wvBNNf013BmkRYiBIsIoOIFdyxs08XMgkUsg02h//SQg/ xGkF2k8V1SBumGC9G5jEQLd+VOVR438inCri/k1YAvtysAiF6xKq35+95xaI2nmY6G/n kOYpj4h+Ggf1FU74dRh1lRilwafLaVsP37FoMnQeYsll8Ow0SsieXnveOE256Xpvz3H/ jX6X5gi/tlTS1FG6uBEeCPatXucGpoPRuVvwPA/pRbtjV6Ts37BHNRwHh4fwXWqszchE w2sA== 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=l3V9iTG9g26Cs+QhDyA7uqjvwWArB5/ivtN2uHVg0UyT+QUy9iv8dTJqYweWtzRXQS HSi23LCJLUe5SJSHaRNhmJBlega/fmYwvx9lHwx3RXBgIDcZis6PvWH1S1maW1LLCNai t+KthT84DG7hmOAlhgvSbs6qMptrJGFU8McOS39fYHbPSB3cUDAf3a0LMtwKxuCzhmq/ FQzB40eKSx5jH0r0ohnbJYNmxZiFgXQygGi1I4a1iM3iN0fBe3VKzdY5x1M9l/P1unRw ma3LblqgX1Vv1V/ysbkVVnFgU8N2MoadOWLhmi1+1TYazo7E6t3AAwAjNmaeVAHSv2JQ j1sw== X-Gm-Message-State: APjAAAWpZVEzIZ60PLu3eedoKou6LpcK71JYBZ9d7QxHAniSzksQ86Ci rv6L77L2SAvaxjqjJyCjbOc2xPZj1g== X-Google-Smtp-Source: APXvYqzFOehBFyyg25Uy8FMQIbAAFlItzOyqW/d56f2jeFCIlA6Xd5MJmEulmym1bP6NEsriCcjKrg== X-Received: by 2002:a5d:554b:: with SMTP id g11mr3106806wrw.10.1561546346986; Wed, 26 Jun 2019 03:52:26 -0700 (PDT) Received: from box.eng.vmware.com ([146.247.46.5]) by smtp.gmail.com with ESMTPSA id s10sm15456929wrt.49.2019.06.26.03.52.26 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Wed, 26 Jun 2019 03:52:26 -0700 (PDT) From: "Slavomir Kaslev (VMware)" To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org Subject: [PATCH v13 10/13] trace-cmd: Try to autodetect number of guest CPUs in setup-guest if not specified Date: Wed, 26 Jun 2019 13:52:06 +0300 Message-Id: <20190626105209.13200-11-slavomir.kaslev@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190626105209.13200-1-slavomir.kaslev@gmail.com> References: <20190626105209.13200-1-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"