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=-14.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, 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 777D7C433E0 for ; Sun, 31 Jan 2021 00:01:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2684964E15 for ; Sun, 31 Jan 2021 00:01:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232726AbhA3X6g convert rfc822-to-8bit (ORCPT ); Sat, 30 Jan 2021 18:58:36 -0500 Received: from us-smtp-delivery-44.mimecast.com ([207.211.30.44]:31466 "EHLO us-smtp-delivery-44.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232565AbhA3Xuc (ORCPT ); Sat, 30 Jan 2021 18:50:32 -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-537-fARGiX7APLWKGe_hyXdMgQ-1; Sat, 30 Jan 2021 18:49:29 -0500 X-MC-Unique: fARGiX7APLWKGe_hyXdMgQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E75E8107ACE8; Sat, 30 Jan 2021 23:49:27 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.192.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id 82F9460DA0; Sat, 30 Jan 2021 23:49:25 +0000 (UTC) From: Jiri Olsa To: Arnaldo Carvalho de Melo Cc: Alexei Budankov , lkml , Peter Zijlstra , Ingo Molnar , Mark Rutland , Namhyung Kim , Alexander Shishkin , Michael Petlan , Ian Rogers , Stephane Eranian Subject: [PATCH 09/24] perf daemon: Add signalfd support Date: Sun, 31 Jan 2021 00:48:41 +0100 Message-Id: <20210130234856.271282-10-jolsa@kernel.org> In-Reply-To: <20210130234856.271282-1-jolsa@kernel.org> References: <20210129134855.195810-1-jolsa@redhat.com> <20210130234856.271282-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jolsa@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset=WINDOWS-1252 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Using signalfd fd for tracking SIGCHLD signals as notification for perf session termination. This way we don't need to actively check for child status, but we are notified if there's change. Suggested-by: Alexei Budankov Signed-off-by: Jiri Olsa --- tools/perf/builtin-daemon.c | 147 ++++++++++++++++++++++++++++++++++-- 1 file changed, 141 insertions(+), 6 deletions(-) diff --git a/tools/perf/builtin-daemon.c b/tools/perf/builtin-daemon.c index 324666058842..69d3af70b642 100644 --- a/tools/perf/builtin-daemon.c +++ b/tools/perf/builtin-daemon.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include #include @@ -16,6 +17,8 @@ #include #include #include +#include +#include #include #include #include "builtin.h" @@ -81,6 +84,7 @@ struct daemon { struct list_head sessions; FILE *out; char perf[PATH_MAX]; + int signal_fd; }; static struct daemon __daemon = { @@ -351,6 +355,103 @@ static int session__run(struct session *session, struct daemon *daemon) return -1; } +static pid_t handle_signalfd(struct daemon *daemon) +{ + struct signalfd_siginfo si; + struct session *session; + ssize_t err; + int status; + pid_t pid; + + err = read(daemon->signal_fd, &si, sizeof(struct signalfd_siginfo)); + if (err != sizeof(struct signalfd_siginfo)) + return -1; + + list_for_each_entry(session, &daemon->sessions, list) { + + if (session->pid != (int) si.ssi_pid) + continue; + + pid = waitpid(session->pid, &status, 0); + if (pid == session->pid) { + if (WIFEXITED(status)) { + pr_info("session '%s' exited, status=%d\n", + session->name, WEXITSTATUS(status)); + } else if (WIFSIGNALED(status)) { + pr_info("session '%s' killed (signal %d)\n", + session->name, WTERMSIG(status)); + } else if (WIFSTOPPED(status)) { + pr_info("session '%s' stopped (signal %d)\n", + session->name, WSTOPSIG(status)); + } else { + pr_info("session '%s' Unexpected status (0x%x)\n", + session->name, status); + } + } + + session->state = SESSION_STATE__KILL; + session->pid = -1; + return pid; + } + + return 0; +} + +static int session__wait(struct session *session, struct daemon *daemon, int secs) +{ + struct pollfd pollfd = { + .fd = daemon->signal_fd, + .events = POLLIN, + }; + pid_t wpid = 0, pid = session->pid; + time_t start; + + start = time(NULL); + + do { + if (poll(&pollfd, 1, 1000)) + wpid = handle_signalfd(daemon); + + if (start + secs < time(NULL)) + return -1; + } while (wpid != pid); + + return 0; +} + +static bool daemon__has_alive_session(struct daemon *daemon) +{ + struct session *session; + + list_for_each_entry(session, &daemon->sessions, list) { + if (session->pid != -1) + return true; + } + + return false; +} + +static int daemon__wait(struct daemon *daemon, int secs) +{ + struct pollfd pollfd = { + .fd = daemon->signal_fd, + .events = POLLIN, + }; + time_t start; + + start = time(NULL); + + do { + if (poll(&pollfd, 1, 1000)) + handle_signalfd(daemon); + + if (start + secs < time(NULL)) + return -1; + } while (daemon__has_alive_session(daemon)); + + return 0; +} + static int setup_server_socket(struct daemon *daemon) { struct sockaddr_un addr; @@ -456,9 +557,13 @@ static int session__signal(struct session *session, int sig) return kill(session->pid, sig); } -static void session__kill(struct session *session) +static void session__kill(struct session *session, struct daemon *daemon) { session__signal(session, SIGTERM); + if (session__wait(session, daemon, 10)) { + session__signal(session, SIGKILL); + session__wait(session, daemon, 10); + } } static void daemon__signal(struct daemon *daemon, int sig) @@ -486,6 +591,10 @@ static void session__remove(struct session *session) static void daemon__kill(struct daemon *daemon) { daemon__signal(daemon, SIGTERM); + if (daemon__wait(daemon, 10)) { + daemon__signal(daemon, SIGKILL); + daemon__wait(daemon, 10); + } } static void __daemon__free(struct daemon *daemon) @@ -523,7 +632,7 @@ static int daemon__reconfig(struct daemon *daemon) /* Remove session. */ if (session->state == SESSION_STATE__KILL) { if (session->pid > 0) { - session__kill(session); + session__kill(session, daemon); pr_info("reconfig: session '%s' killed\n", session->name); } session__remove(session); @@ -532,7 +641,7 @@ static int daemon__reconfig(struct daemon *daemon) /* Reconfig session. */ if (session->pid > 0) { - session__kill(session); + session__kill(session, daemon); pr_info("reconfig: session '%s' killed\n", session->name); } if (session__run(session, daemon)) @@ -690,6 +799,20 @@ static int go_background(struct daemon *daemon) return 0; } +static int setup_signalfd(struct daemon *daemon) +{ + sigset_t mask; + + sigemptyset(&mask); + sigaddset(&mask, SIGCHLD); + + if (sigprocmask(SIG_BLOCK, &mask, NULL) == -1) + return -1; + + daemon->signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC); + return daemon->signal_fd; +} + static int __cmd_start(struct daemon *daemon, struct option parent_options[], int argc, const char **argv) { @@ -699,8 +822,8 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[], OPT_PARENT(parent_options), OPT_END() }; - int sock_fd = -1, conf_fd = -1; - int sock_pos, file_pos; + int sock_fd = -1, conf_fd = -1, signal_fd = -1; + int sock_pos, file_pos, signal_pos; struct fdarray fda; int err = 0; @@ -732,7 +855,7 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[], pr_info("daemon started (pid %d)\n", getpid()); - fdarray__init(&fda, 2); + fdarray__init(&fda, 3); sock_fd = setup_server_socket(daemon); if (sock_fd < 0) @@ -742,6 +865,10 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[], if (conf_fd < 0) goto out; + signal_fd = setup_signalfd(daemon); + if (signal_fd < 0) + goto out; + sock_pos = fdarray__add(&fda, sock_fd, POLLIN|POLLERR|POLLHUP, 0); if (sock_pos < 0) goto out; @@ -750,6 +877,10 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[], if (file_pos < 0) goto out; + signal_pos = fdarray__add(&fda, signal_fd, POLLIN|POLLERR|POLLHUP, 0); + if (signal_pos < 0) + goto out; + signal(SIGINT, sig_handler); signal(SIGTERM, sig_handler); @@ -763,6 +894,8 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[], err = handle_server_socket(daemon, sock_fd); if (fda.entries[file_pos].revents & POLLIN) err = handle_config_changes(daemon, conf_fd, &reconfig); + if (fda.entries[signal_pos].revents & POLLIN) + err = handle_signalfd(daemon) < 0; if (reconfig) err = setup_server_config(daemon); @@ -778,6 +911,8 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[], close(sock_fd); if (conf_fd != -1) close(conf_fd); + if (conf_fd != -1) + close(signal_fd); pr_info("daemon exited\n"); fclose(daemon->out); -- 2.29.2