Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161414Ab2JXV4r (ORCPT ); Wed, 24 Oct 2012 17:56:47 -0400 Received: from mail-da0-f46.google.com ([209.85.210.46]:43238 "EHLO mail-da0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161299Ab2JXV4o (ORCPT ); Wed, 24 Oct 2012 17:56:44 -0400 From: Juri Lelli To: peterz@infradead.org, tglx@linutronix.de Cc: mingo@redhat.com, rostedt@goodmis.org, oleg@redhat.com, fweisbec@gmail.com, darren@dvhart.com, johan.eker@ericsson.com, p.faure@akatech.ch, linux-kernel@vger.kernel.org, claudio@evidence.eu.com, michael@amarulasolutions.com, fchecconi@gmail.com, tommaso.cucinotta@sssup.it, juri.lelli@gmail.com, nicola.manica@disi.unitn.it, luca.abeni@unitn.it, dhaval.giani@gmail.com, hgu1972@gmail.com, paulmck@linux.vnet.ibm.com, raistlin@linux.it, insop.song@ericsson.com, liming.wang@windriver.com, jkacur@redhat.com, harald.gustafsson@ericsson.com, vincent.guittot@linaro.org Subject: [PATCH 08/16] sched: add period support for -deadline tasks. Date: Wed, 24 Oct 2012 14:53:46 -0700 Message-Id: <1351115634-8420-9-git-send-email-juri.lelli@gmail.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1351115634-8420-1-git-send-email-juri.lelli@gmail.com> References: <1351115634-8420-1-git-send-email-juri.lelli@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4413 Lines: 121 From: Harald Gustafsson Make it possible to specify a period (different or equal than deadline) for -deadline tasks. Signed-off-by: Harald Gustafsson Signed-off-by: Dario Faggioli Signed-off-by: Juri Lelli --- include/linux/sched.h | 1 + kernel/sched/core.c | 15 ++++++++++++--- kernel/sched/dl.c | 10 +++++++--- 3 files changed, 20 insertions(+), 6 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 92ae764..cfbb086 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1236,6 +1236,7 @@ struct sched_dl_entity { */ u64 dl_runtime; /* maximum runtime for each instance */ u64 dl_deadline; /* relative deadline of each instance */ + u64 dl_period; /* separation of two instances (period) */ /* * Actual scheduling parameters. Initialized with the values above, diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 934d3c3..9b6b988 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1534,6 +1534,7 @@ static void __sched_fork(struct task_struct *p) hrtimer_init(&p->dl.dl_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); p->dl.dl_runtime = p->dl.runtime = 0; p->dl.dl_deadline = p->dl.deadline = 0; + p->dl.dl_period = 0; p->dl.flags = 0; INIT_LIST_HEAD(&p->rt.run_list); @@ -3726,6 +3727,10 @@ __setparam_dl(struct task_struct *p, const struct sched_param2 *param2) init_dl_task_timer(dl_se); dl_se->dl_runtime = param2->sched_runtime; dl_se->dl_deadline = param2->sched_deadline; + if (param2->sched_period != 0) + dl_se->dl_period = param2->sched_period; + else + dl_se->dl_period = dl_se->dl_deadline; dl_se->flags = param2->sched_flags; dl_se->dl_throttled = 0; dl_se->dl_new = 1; @@ -3739,19 +3744,23 @@ __getparam_dl(struct task_struct *p, struct sched_param2 *param2) param2->sched_priority = p->rt_priority; param2->sched_runtime = dl_se->dl_runtime; param2->sched_deadline = dl_se->dl_deadline; + param2->sched_period = dl_se->dl_period; param2->sched_flags = dl_se->flags; } /* * This function validates the new parameters of a -deadline task. * We ask for the deadline not being zero, and greater or equal - * than the runtime. + * than the runtime, as well as the period of being zero or + * greater than deadline. */ static bool __checkparam_dl(const struct sched_param2 *prm) { - return prm && (&prm->sched_deadline) != 0 && - (s64)(&prm->sched_deadline - &prm->sched_runtime) >= 0; + return prm && prm->sched_deadline != 0 && + (prm->sched_period == 0 || + (s64)(prm->sched_period - prm->sched_deadline) >= 0) && + (s64)(prm->sched_deadline - prm->sched_runtime) >= 0; } /* diff --git a/kernel/sched/dl.c b/kernel/sched/dl.c index 38e6071..0adbffb 100644 --- a/kernel/sched/dl.c +++ b/kernel/sched/dl.c @@ -288,7 +288,7 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se) * arbitrary large. */ while (dl_se->runtime <= 0) { - dl_se->deadline += dl_se->dl_deadline; + dl_se->deadline += dl_se->dl_period; dl_se->runtime += dl_se->dl_runtime; } @@ -328,9 +328,13 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se) * * This function returns true if: * - * runtime / (deadline - t) > dl_runtime / dl_deadline , + * runtime / (deadline - t) > dl_runtime / dl_period , * * IOW we can't recycle current parameters. + * + * Notice that the bandwidth check is done against the period. For + * task with deadline equal to period this is the same of using + * dl_deadline instead of dl_period in the equation above. */ static bool dl_entity_overflow(struct sched_dl_entity *dl_se, u64 t) { @@ -349,7 +353,7 @@ static bool dl_entity_overflow(struct sched_dl_entity *dl_se, u64 t) * to the (absolute) deadline. Therefore, overflowing the u64 * type is very unlikely to occur in both cases. */ - left = mul_u64_u64(dl_se->dl_deadline, dl_se->runtime); + left = mul_u64_u64(dl_se->dl_period, dl_se->runtime); right = mul_u64_u64((dl_se->deadline - t), dl_se->dl_runtime); if (cmp_u128(left, right) > 0) -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/