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=-15.3 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_SANE_1 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 3B480C43460 for ; Tue, 6 Apr 2021 08:45:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 131C96139B for ; Tue, 6 Apr 2021 08:45:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244477AbhDFIpv (ORCPT ); Tue, 6 Apr 2021 04:45:51 -0400 Received: from mga17.intel.com ([192.55.52.151]:34325 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244513AbhDFIpu (ORCPT ); Tue, 6 Apr 2021 04:45:50 -0400 IronPort-SDR: HjHu8DPAyTtu03q0ABuzgmaJpRUeYXRZL0m/9/XJqsdEDiQo6iUcjGw6kko3QdmOT8WyB0CmeE ooSxMsuKmRlg== X-IronPort-AV: E=McAfee;i="6000,8403,9945"; a="173099344" X-IronPort-AV: E=Sophos;i="5.81,308,1610438400"; d="scan'208";a="173099344" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Apr 2021 01:45:42 -0700 IronPort-SDR: 4tFQ4+jP7sD6tNAgsAfsZnSKSeK0xs4FhzPtyH85rpGskQlfhzlN0dnWaDIIIy4hTliXHdY+9Z 4/iCW4Ie+U4g== X-IronPort-AV: E=Sophos;i="5.81,308,1610438400"; d="scan'208";a="421122029" Received: from abaydur-mobl1.ccr.corp.intel.com (HELO [10.249.228.164]) ([10.249.228.164]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Apr 2021 01:45:39 -0700 Subject: [PATCH v4 05/12] perf record: start threads in the beginning of trace streaming From: "Bayduraev, Alexey V" To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , Namhyung Kim , Alexander Shishkin , Peter Zijlstra , Ingo Molnar , linux-kernel , Andi Kleen , Adrian Hunter , Alexei Budankov , Alexander Antonov References: <6c15adcb-6a9d-320e-70b5-957c4c8b6ff2@linux.intel.com> Organization: Intel Corporation Message-ID: Date: Tue, 6 Apr 2021 11:45:37 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.9.0 MIME-Version: 1.0 In-Reply-To: <6c15adcb-6a9d-320e-70b5-957c4c8b6ff2@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit 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 | 103 +++++++++++++++++++++++++++++++++++- 1 file changed, 102 insertions(+), 1 deletion(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 4612314853c1..339198b2e37d 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1412,6 +1412,64 @@ 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. Error %m", thread->tid); + + 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. Error %m", thread->tid); + + return NULL; +} + static void record__init_features(struct record *rec) { struct perf_session *session = rec->session; @@ -1849,13 +1907,56 @@ 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. Error: %m\n"); + 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. Error: %m\n"); + 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. Error: %m\n"); + ret = -1; + } + + return ret; } static int record__stop_threads(struct record *rec, unsigned long *waking) -- 2.19.0