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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 35160C11F78 for ; Mon, 12 Jul 2021 07:09:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1F560610D1 for ; Mon, 12 Jul 2021 07:09:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239126AbhGLHLo (ORCPT ); Mon, 12 Jul 2021 03:11:44 -0400 Received: from mga18.intel.com ([134.134.136.126]:45893 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239285AbhGLGth (ORCPT ); Mon, 12 Jul 2021 02:49:37 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10042"; a="197204400" X-IronPort-AV: E=Sophos;i="5.84,232,1620716400"; d="scan'208";a="197204400" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jul 2021 23:46:49 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.84,232,1620716400"; d="scan'208";a="491916163" Received: from nntpat99-84.inn.intel.com ([10.125.99.84]) by FMSMGA003.fm.intel.com with ESMTP; 11 Jul 2021 23:46:45 -0700 From: Alexey Bayduraev To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , Namhyung Kim , Alexander Shishkin , Peter Zijlstra , Ingo Molnar , linux-kernel , Andi Kleen , Adrian Hunter , Alexander Antonov , Alexei Budankov , Riccardo Mancini Subject: [PATCH v10 07/24] perf record: Start threads in the beginning of trace streaming Date: Mon, 12 Jul 2021 09:46:07 +0300 Message-Id: <993b734f362b2740e9758abd68a61f2362a9a119.1626072009.git.alexey.v.bayduraev@linux.intel.com> X-Mailer: git-send-email 2.19.0 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Start thread in detached state because its management is implemented via messaging to avoid any scaling issues. Block signals prior thread start so only main tool thread would be notified on external async signals during data collection. Thread affinity mask is used to assign eligible cpus for the thread to run. Wait and sync on thread start using thread ack pipe. Acked-by: Namhyung Kim Signed-off-by: Alexey Bayduraev --- tools/perf/builtin-record.c | 109 +++++++++++++++++++++++++++++++++++- 1 file changed, 108 insertions(+), 1 deletion(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 2f907186468a..cb8d320d20a9 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1484,6 +1484,67 @@ static void record__thread_munmap_filtered(struct fdarray *fda, int fd, perf_mmap__put(map); } +static void *record__thread(void *arg) +{ + enum thread_msg msg = THREAD_MSG__READY; + bool terminate = false; + struct fdarray *pollfd; + int err, ctlfd_pos; + + thread = arg; + thread->tid = gettid(); + + err = write(thread->pipes.ack[1], &msg, sizeof(msg)); + if (err == -1) + pr_err("threads[%d]: failed to notify on start: %s", thread->tid, strerror(errno)); + + pr_debug("threads[%d]: started on cpu=%d\n", thread->tid, sched_getcpu()); + + pollfd = &thread->pollfd; + ctlfd_pos = thread->ctlfd_pos; + + for (;;) { + unsigned long long hits = thread->samples; + + if (record__mmap_read_all(thread->rec, false) < 0 || terminate) + break; + + if (hits == thread->samples) { + + err = fdarray__poll(pollfd, -1); + /* + * Propagate error, only if there's any. Ignore positive + * number of returned events and interrupt error. + */ + if (err > 0 || (err < 0 && errno == EINTR)) + err = 0; + thread->waking++; + + if (fdarray__filter(pollfd, POLLERR | POLLHUP, + record__thread_munmap_filtered, NULL) == 0) + break; + } + + if (pollfd->entries[ctlfd_pos].revents & POLLHUP) { + terminate = true; + close(thread->pipes.msg[0]); + thread->pipes.msg[0] = -1; + pollfd->entries[ctlfd_pos].fd = -1; + pollfd->entries[ctlfd_pos].events = 0; + } + + pollfd->entries[ctlfd_pos].revents = 0; + } + record__mmap_read_all(thread->rec, true); + + err = write(thread->pipes.ack[1], &msg, sizeof(msg)); + if (err == -1) + pr_err("threads[%d]: failed to notify on termination: %s", + thread->tid, strerror(errno)); + + return NULL; +} + static void record__init_features(struct record *rec) { struct perf_session *session = rec->session; @@ -1948,13 +2009,59 @@ static int record__terminate_thread(struct record_thread *thread_data) static int record__start_threads(struct record *rec) { + int t, tt, ret = 0, nr_threads = rec->nr_threads; struct record_thread *thread_data = rec->thread_data; + sigset_t full, mask; + pthread_t handle; + pthread_attr_t attrs; + + sigfillset(&full); + if (sigprocmask(SIG_SETMASK, &full, &mask)) { + pr_err("Failed to block signals on threads start: %s\n", strerror(errno)); + return -1; + } + + pthread_attr_init(&attrs); + pthread_attr_setdetachstate(&attrs, PTHREAD_CREATE_DETACHED); + + for (t = 1; t < nr_threads; t++) { + enum thread_msg msg = THREAD_MSG__UNDEFINED; + + pthread_attr_setaffinity_np(&attrs, + MMAP_CPU_MASK_BYTES(&(thread_data[t].mask->affinity)), + (cpu_set_t *)(thread_data[t].mask->affinity.bits)); + + if (pthread_create(&handle, &attrs, record__thread, &thread_data[t])) { + for (tt = 1; tt < t; tt++) + record__terminate_thread(&thread_data[t]); + pr_err("Failed to start threads: %s\n", strerror(errno)); + ret = -1; + goto out_err; + } + + if (read(thread_data[t].pipes.ack[0], &msg, sizeof(msg)) > 0) + pr_debug2("threads[%d]: sent %s\n", rec->thread_data[t].tid, + thread_msg_tags[msg]); + } + + if (nr_threads > 1) { + sched_setaffinity(0, MMAP_CPU_MASK_BYTES(&thread_data[0].mask->affinity), + (cpu_set_t *)thread_data[0].mask->affinity.bits); + } thread = &thread_data[0]; pr_debug("threads[%d]: started on cpu=%d\n", thread->tid, sched_getcpu()); - return 0; +out_err: + pthread_attr_destroy(&attrs); + + if (sigprocmask(SIG_SETMASK, &mask, NULL)) { + pr_err("Failed to unblock signals on threads start: %s\n", strerror(errno)); + ret = -1; + } + + return ret; } static int record__stop_threads(struct record *rec, unsigned long *waking) -- 2.19.0