From nobody Mon May 20 17:29:57 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1614695441; cv=none; d=zohomail.com; s=zohoarc; b=ZtW5O3nuSj87ctAdlPahzGuDbqJ6h8gPw+pXrbpyjBpKzfwghmseWypw2zEAGdECjzetRsjkJtDLzyXPszxUlJUKnRXKG8tCBq67iEwyXOFxwWa/UXVn8Shma4Qbzozd5ciiBTxRhCUdMZEkAbNEQri1DYWy2ba9rDxFJJwhEnA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1614695441; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Sender:Subject:To; bh=9mhjnnXiYmnqklutiBFfmN5pMjO0IsLmHlehd1kxL48=; b=fjbULmfBuD8L1JrQF5qm1NaRljyULdH4K4zLdUtZoYnK2IxB0ZttAGtqJnXbNnkGjZf1buXuVR3NMjL3w6uMfcggB+oe6NJ1WwMS50Ubb1Glm6+fHfEhzjUetZJBDUZhtdLYw2DfaWHDhOslowafVKHvYyLHSWXX4Z+QW+WQJPk= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 16146954413471009.0300994939416; Tue, 2 Mar 2021 06:30:41 -0800 (PST) Received: from localhost ([::1]:39648 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lH62p-0002E8-Ex for importer@patchew.org; Tue, 02 Mar 2021 09:30:39 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:35330) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lH60R-0000v7-Qx for qemu-devel@nongnu.org; Tue, 02 Mar 2021 09:28:11 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:31444) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1lH60O-00014E-KF for qemu-devel@nongnu.org; Tue, 02 Mar 2021 09:28:10 -0500 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-389-z6gBx-B8PXqHsdPHrtjGRg-1; Tue, 02 Mar 2021 09:28:06 -0500 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 564F6874985; Tue, 2 Mar 2021 14:28:05 +0000 (UTC) Received: from localhost (ovpn-114-138.ams2.redhat.com [10.36.114.138]) by smtp.corp.redhat.com (Postfix) with ESMTP id BA46560C05; Tue, 2 Mar 2021 14:28:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1614695287; 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: content-transfer-encoding:content-transfer-encoding; bh=9mhjnnXiYmnqklutiBFfmN5pMjO0IsLmHlehd1kxL48=; b=N4HWV8TQ9AUBg1eq6MAMyrgORvAf+t3xID1SeYOVSztfXYUr2GoUUJZ2mTza+39GqtS7hO oHQC3r7w4/M5CrD5uCrCLoicG/CUYiPxVEf2TlwSYTLKg8TiJS8glYNeX20fhX7zeKDJ0K ArEepgG6Spkv4qNeb+aocTtNIiqS4DQ= X-MC-Unique: z6gBx-B8PXqHsdPHrtjGRg-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [PATCH v3] qemu-storage-daemon: add --pidfile option Date: Tue, 2 Mar 2021 14:27:46 +0000 Message-Id: <20210302142746.170535-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=216.205.24.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, MIME_BASE64_TEXT=1.741, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Daniel Berrange , qemu-block@nongnu.org, afrosi@redhat.com, "Richard W . M . Jones" , Stefan Hajnoczi Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" Daemons often have a --pidfile option where the pid is written to a file so that scripts can stop the daemon by sending a signal. The pid file also acts as a lock to prevent multiple instances of the daemon from launching for a given pid file. QEMU, qemu-nbd, qemu-ga, virtiofsd, and qemu-pr-helper all support the --pidfile option. Add it to qemu-storage-daemon too. Reported-by: Richard W.M. Jones Signed-off-by: Stefan Hajnoczi Reviewed-by: Richard W.M. Jones --- v3: * Add --pidfile help output [Kevin] docs/tools/qemu-storage-daemon.rst | 14 +++++++++++ storage-daemon/qemu-storage-daemon.c | 36 ++++++++++++++++++++++++++++ 2 files changed, 50 insertions(+) diff --git a/docs/tools/qemu-storage-daemon.rst b/docs/tools/qemu-storage-d= aemon.rst index f63627eaf6..3d9704d835 100644 --- a/docs/tools/qemu-storage-daemon.rst +++ b/docs/tools/qemu-storage-daemon.rst @@ -118,6 +118,20 @@ Standard options: List object properties with ``,help``. See the :manpage:`qemu(1)` manual page for a description of the object properties. =20 +.. option:: --pidfile PATH + + is the path to a file where the daemon writes its pid. This allows scrip= ts to + stop the daemon by sending a signal:: + + $ kill -SIGTERM $( write process ID to a file after startup\n" +"\n" QEMU_HELP_BOTTOM "\n", error_get_progname()); } @@ -126,6 +129,7 @@ enum { OPTION_MONITOR, OPTION_NBD_SERVER, OPTION_OBJECT, + OPTION_PIDFILE, }; =20 extern QemuOptsList qemu_chardev_opts; @@ -164,6 +168,7 @@ static void process_options(int argc, char *argv[]) {"monitor", required_argument, NULL, OPTION_MONITOR}, {"nbd-server", required_argument, NULL, OPTION_NBD_SERVER}, {"object", required_argument, NULL, OPTION_OBJECT}, + {"pidfile", required_argument, NULL, OPTION_PIDFILE}, {"trace", required_argument, NULL, 'T'}, {"version", no_argument, NULL, 'V'}, {0, 0, 0, 0} @@ -275,6 +280,9 @@ static void process_options(int argc, char *argv[]) qobject_unref(args); break; } + case OPTION_PIDFILE: + pid_file =3D optarg; + break; default: g_assert_not_reached(); } @@ -285,6 +293,27 @@ static void process_options(int argc, char *argv[]) } } =20 +static void pid_file_cleanup(void) +{ + unlink(pid_file); +} + +static void pid_file_init(void) +{ + Error *err =3D NULL; + + if (!pid_file) { + return; + } + + if (!qemu_write_pidfile(pid_file, &err)) { + error_reportf_err(err, "cannot create PID file: "); + exit(EXIT_FAILURE); + } + + atexit(pid_file_cleanup); +} + int main(int argc, char *argv[]) { #ifdef CONFIG_POSIX @@ -312,6 +341,13 @@ int main(int argc, char *argv[]) qemu_init_main_loop(&error_fatal); process_options(argc, argv); =20 + /* + * Write the pid file after creating chardevs, exports, and NBD server= s but + * before accepting connections. This ordering is documented. Do not c= hange + * it. + */ + pid_file_init(); + while (!exit_requested) { main_loop_wait(false); } --=20 2.29.2