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,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 70526C433B4 for ; Tue, 4 May 2021 07:05:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 50546613B4 for ; Tue, 4 May 2021 07:05:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229994AbhEDHGW (ORCPT ); Tue, 4 May 2021 03:06:22 -0400 Received: from mga11.intel.com ([192.55.52.93]:41320 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229966AbhEDHGV (ORCPT ); Tue, 4 May 2021 03:06:21 -0400 IronPort-SDR: 2HTzoXdmU5hMXlcPAsPbmyKjFzwMR6ClsGtFJnqHqjxWo5bDsawMRWpYRyCRfwrrwsESdR1TqJ jK4K+kCVYKdg== X-IronPort-AV: E=McAfee;i="6200,9189,9973"; a="194779375" X-IronPort-AV: E=Sophos;i="5.82,271,1613462400"; d="scan'208";a="194779375" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 May 2021 00:05:26 -0700 IronPort-SDR: gfaX7hfh0NQfEV1av/I5C5I+yCtCarCmE+1jaaRHZoBRRRrU4KOkduaVkzfpU+WDaTvUV+ph8J Zb9+57tarBfQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,271,1613462400"; d="scan'208";a="450895315" Received: from nntpat99-84.inn.intel.com ([10.125.99.84]) by fmsmga004.fm.intel.com with ESMTP; 04 May 2021 00:05:22 -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 Subject: [PATCH v5 05/20] perf record: start threads in the beginning of trace streaming Date: Tue, 4 May 2021 10:04:40 +0300 Message-Id: <716be34eac087524a7073734b4ac59660d140529.1619781188.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. Signed-off-by: Alexey Bayduraev --- tools/perf/builtin-record.c | 105 +++++++++++++++++++++++++++++++++++- 1 file changed, 104 insertions(+), 1 deletion(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 52703eceb47f..baf9646c4ac9 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1417,6 +1417,65 @@ 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 = syscall(SYS_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]); + pollfd->entries[ctlfd_pos].fd = -1; + pollfd->entries[ctlfd_pos].events = 0; + } + + pollfd->entries[ctlfd_pos].revents = 0; + } + + 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; @@ -1880,13 +1939,57 @@ static int record__terminate_thread(struct thread_data *thread_data) static int record__start_threads(struct record *rec) { + int t, tt, ret = 0, nr_threads = rec->nr_threads; struct thread_data *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: + 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