Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754590AbdC1Ggi (ORCPT ); Tue, 28 Mar 2017 02:36:38 -0400 Received: from foss.arm.com ([217.140.101.70]:43178 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754477AbdC1Ggh (ORCPT ); Tue, 28 Mar 2017 02:36:37 -0400 From: Dietmar Eggemann To: Peter Zijlstra , Ingo Molnar Cc: LKML , Matt Fleming , Vincent Guittot , Steven Rostedt , Morten Rasmussen , Juri Lelli , Patrick Bellasi Subject: [RFC PATCH 5/5] sched/events: Introduce task_group load tracking trace event Date: Tue, 28 Mar 2017 07:35:41 +0100 Message-Id: <20170328063541.12912-6-dietmar.eggemann@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170328063541.12912-1-dietmar.eggemann@arm.com> References: <20170328063541.12912-1-dietmar.eggemann@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2655 Lines: 91 The trace event key load is mapped to: (1) load : cfs_rq->tg->load_avg The cfs_rq owned by the task_group is used as the only parameter for the trace event because it has a reference to the taskgroup and the cpu. Using the taskgroup as a parameter instead would require the cpu as a second parameter. A task_group is global and not per-cpu data. The cpu key only tells on which cpu the value was gathered. The following list shows examples of the key=value pairs for: (1) a task group: cpu=1 path=/tg1/tg11/tg111 id=4 load=517 (2) an autogroup: cpu=1 path=/autogroup-10 id=0 load=1050 We don't maintain a load signal for a root task group. The trace event is only defined if cfs group scheduling support (CONFIG_FAIR_GROUP_SCHED) is enabled. Signed-off-by: Dietmar Eggemann Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Steven Rostedt --- include/trace/events/sched.h | 31 +++++++++++++++++++++++++++++++ kernel/sched/fair.c | 2 ++ 2 files changed, 33 insertions(+) diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h index 647cfaf528fd..3fe0092176f8 100644 --- a/include/trace/events/sched.h +++ b/include/trace/events/sched.h @@ -673,6 +673,37 @@ TRACE_EVENT(sched_load_se, __entry->cpu, __get_str(path), __entry->id, __entry->comm, __entry->pid, __entry->load, __entry->util) ); + +/* + * Tracepoint for task_group load tracking: + */ +#ifdef CONFIG_FAIR_GROUP_SCHED +TRACE_EVENT(sched_load_tg, + + TP_PROTO(struct cfs_rq *cfs_rq), + + TP_ARGS(cfs_rq), + + TP_STRUCT__entry( + __field( int, cpu ) + __dynamic_array(char, path, + __trace_sched_path(cfs_rq, NULL, 0) ) + __field( int, id ) + __field( long, load ) + ), + + TP_fast_assign( + __entry->cpu = cfs_rq->rq->cpu; + __trace_sched_path(cfs_rq, __get_dynamic_array(path), + __get_dynamic_array_len(path)); + __entry->id = cfs_rq->tg->css.id; + __entry->load = atomic_long_read(&cfs_rq->tg->load_avg); + ), + + TP_printk("cpu=%d path=%s id=%d load=%ld", __entry->cpu, + __get_str(path), __entry->id, __entry->load) +); +#endif /* CONFIG_FAIR_GROUP_SCHED */ #endif /* CONFIG_SMP */ #endif /* _TRACE_SCHED_H */ diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index d1dcb19f5b55..dbe2d5ef8b9e 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2997,6 +2997,8 @@ static inline void update_tg_load_avg(struct cfs_rq *cfs_rq, int force) atomic_long_add(delta, &cfs_rq->tg->load_avg); cfs_rq->tg_load_avg_contrib = cfs_rq->avg.load_avg; } + + trace_sched_load_tg(cfs_rq); } /* -- 2.11.0