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 2BA6AC4338F for ; Tue, 17 Aug 2021 08:24:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0F9C960FA0 for ; Tue, 17 Aug 2021 08:24:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239256AbhHQIYo (ORCPT ); Tue, 17 Aug 2021 04:24:44 -0400 Received: from mga07.intel.com ([134.134.136.100]:11537 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239268AbhHQIY0 (ORCPT ); Tue, 17 Aug 2021 04:24:26 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10078"; a="279763211" X-IronPort-AV: E=Sophos;i="5.84,328,1620716400"; d="scan'208";a="279763211" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Aug 2021 01:23:54 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.84,328,1620716400"; d="scan'208";a="471080242" Received: from nntpat99-84.inn.intel.com ([10.125.99.84]) by orsmga008.jf.intel.com with ESMTP; 17 Aug 2021 01:23:51 -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 v11 07/24] perf record: Start threads in the beginning of trace streaming Date: Tue, 17 Aug 2021 11:23:10 +0300 Message-Id: <0b55237124aee9e348449540691320b66879be6c.1629186429.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 Reviewed-by: Riccardo Mancini Tested-by: Riccardo Mancini 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 04e77b5487bb..fb1c1b46dd04 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; @@ -1918,13 +1979,59 @@ 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