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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC606C43217 for ; Thu, 17 Nov 2022 13:47:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240237AbiKQNqv (ORCPT ); Thu, 17 Nov 2022 08:46:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55650 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234533AbiKQNqf (ORCPT ); Thu, 17 Nov 2022 08:46:35 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B20B6725FE; Thu, 17 Nov 2022 05:46:32 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 454A661E4C; Thu, 17 Nov 2022 13:46:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3533AC4347C; Thu, 17 Nov 2022 13:46:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1668692791; bh=ybjnmnbdgG5oznw+D3D3EoANpgY2rjuP8S4++LExstU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mOnTnexPNWQGIvfeA8LgAOjPntAA7EzwHGMkMAHVT1ht1Zt7LGp6GME0fVfhWUwJ2 FjVIbhWZXwQsw9+3JdIN4dKhoSnzih7sKsoTmOOJuy8c1HPszpISZ1geeTIlNBX2rZ ZgnpddVVtulWg07K0p8j4Gqc7CW5uQ2bhFR8mp5eub6/Lc7U/A2YurbL8y6ZmSOqNr iPPAzD/AjDwAT5ncIry9hBsmqEEgPPT+ihHizoC1elRNLox+TRkYeaQroZquapzTMD x+zeoGFq3r1DmRfpWUaCf8zrr9SDqEfjKRU2lG0bPsa//tQ5hdbfXt6wRCXcLr+ag6 sHdoJ9b+iscpQ== From: Daniel Bristot de Oliveira To: Daniel Bristot de Oliveira , Steven Rostedt Cc: Masami Hiramatsu , Jonathan Corbet , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/4] tracing/osnoise: Add OSNOISE_WORKLOAD option Date: Thu, 17 Nov 2022 14:46:19 +0100 Message-Id: X-Mailer: git-send-email 2.32.0 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The osnoise tracer is not only a tracer, and a set of tracepoints, but also a workload dispatcher. In preparation for having other workloads, e.g., in user-space, add an option to avoid dispatching the workload. By not dispatching the workload, the osnoise: tracepoints become generic events to measure the execution time of *any* task on Linux. For example: # cd /sys/kernel/tracing/ # cat osnoise/options DEFAULTS OSNOISE_WORKLOAD # echo NO_OSNOISE_WORKLOAD > osnoise/options # cat osnoise/options NO_DEFAULTS NO_OSNOISE_WORKLOAD # echo osnoise > set_event # echo osnoise > current_tracer # tail -8 trace make-94722 [002] d..3. 1371.794507: thread_noise: make:94722 start 1371.794302286 duration 200897 ns sh-121042 [020] d..3. 1371.794534: thread_noise: sh:121042 start 1371.781610976 duration 8943683 ns make-121097 [005] d..3. 1371.794542: thread_noise: make:121097 start 1371.794481522 duration 60444 ns <...>-40 [005] d..3. 1371.794550: thread_noise: migration/5:40 start 1371.794542256 duration 7154 ns -0 [018] dNh2. 1371.794554: irq_noise: reschedule:253 start 1371.794553547 duration 40 ns -0 [018] dNh2. 1371.794561: irq_noise: local_timer:236 start 1371.794556222 duration 4890 ns -0 [018] .Ns2. 1371.794563: softirq_noise: SCHED:7 start 1371.794561803 duration 992 ns -0 [018] d..3. 1371.794566: thread_noise: swapper/18:0 start 1371.781368110 duration 13191798 ns In preparation for the rtla exec_time tracer/tool and rtla osnoise --user option. Cc: Daniel Bristot de Oliveira Cc: Steven Rostedt Cc: Masami Hiramatsu Cc: Jonathan Corbet Signed-off-by: Daniel Bristot de Oliveira --- kernel/trace/trace_osnoise.c | 28 ++++++++++++++++++++++------ 1 file changed, 22 insertions(+), 6 deletions(-) diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index 17b77fe3950b..3f10dd1f2f1c 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -53,12 +53,13 @@ */ enum osnoise_options_index { OSN_DEFAULTS = 0, + OSN_WORKLOAD, OSN_MAX }; -static const char * const osnoise_options_str[OSN_MAX] = { "DEFAULTS" }; +static const char * const osnoise_options_str[OSN_MAX] = { "DEFAULTS", "OSNOISE_WORKLOAD" }; -#define OSN_DEFAULT_OPTIONS 0 +#define OSN_DEFAULT_OPTIONS 0x2 unsigned long osnoise_options = OSN_DEFAULT_OPTIONS; /* @@ -1186,11 +1187,12 @@ trace_sched_switch_callback(void *data, bool preempt, unsigned int prev_state) { struct osnoise_variables *osn_var = this_cpu_osn_var(); + int workload = test_bit(OSN_WORKLOAD, &osnoise_options); - if (p->pid != osn_var->pid) + if ((p->pid != osn_var->pid) || !workload) thread_exit(osn_var, p); - if (n->pid != osn_var->pid) + if ((n->pid != osn_var->pid) || !workload) thread_entry(osn_var, n); } @@ -1723,9 +1725,16 @@ static void stop_kthread(unsigned int cpu) struct task_struct *kthread; kthread = per_cpu(per_cpu_osnoise_var, cpu).kthread; - if (kthread) + if (kthread) { kthread_stop(kthread); - per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL; + per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL; + } else { + if (!test_bit(OSN_WORKLOAD, &osnoise_options)) { + per_cpu(per_cpu_osnoise_var, cpu).sampling = false; + barrier(); + return; + } + } } /* @@ -1759,6 +1768,13 @@ static int start_kthread(unsigned int cpu) snprintf(comm, 24, "timerlat/%d", cpu); main = timerlat_main; } else { + /* if no workload, just return */ + if (!test_bit(OSN_WORKLOAD, &osnoise_options)) { + per_cpu(per_cpu_osnoise_var, cpu).sampling = true; + barrier(); + return 0; + } + snprintf(comm, 24, "osnoise/%d", cpu); } -- 2.32.0