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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 4333AC76191 for ; Thu, 25 Jul 2019 07:09:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2386020840 for ; Thu, 25 Jul 2019 07:09:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729526AbfGYHJr (ORCPT ); Thu, 25 Jul 2019 03:09:47 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:4268 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729448AbfGYHJI (ORCPT ); Thu, 25 Jul 2019 03:09:08 -0400 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x6P76WYJ115216 for ; Thu, 25 Jul 2019 03:09:08 -0400 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ty66bbwj1-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 25 Jul 2019 03:09:07 -0400 Received: from localhost by e06smtp07.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 25 Jul 2019 08:09:02 +0100 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x6P791Eu42926314 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 25 Jul 2019 07:09:02 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D09FF4C04E; Thu, 25 Jul 2019 07:09:01 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 64D804C046; Thu, 25 Jul 2019 07:09:00 +0000 (GMT) Received: from localhost.in.ibm.com (unknown [9.124.35.169]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 25 Jul 2019 07:09:00 +0000 (GMT) From: Parth Shah To: peterz@infradead.org, mingo@redhat.com Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, patrick.bellasi@arm.com, dietmar.eggemann@arm.com, daniel.lezcano@linaro.org, subhra.mazumdar@oracle.com Subject: [RFC v4 1/8] sched/core: Add manual jitter classification using sched_setattr syscall Date: Thu, 25 Jul 2019 12:38:50 +0530 X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190725070857.6639-1-parth@linux.ibm.com> References: <20190725070857.6639-1-parth@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 19072507-0028-0000-0000-000003879ECE X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19072507-0029-0000-0000-00002447DD29 Message-Id: <20190725070857.6639-2-parth@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-07-25_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1907250085 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Jitter tasks are short/bursty tasks, typically performing some housekeeping work and are less important in the overall scheme of things. So provide a way to mark the task as jitter with the use of additional flag to the existing task attribute. Also provide an interface from the userspace which uses sched_setattr syscall to mark tasks as jitter. Signed-off-by: Parth Shah --- include/linux/sched.h | 1 + include/uapi/linux/sched.h | 4 +++- kernel/sched/core.c | 9 +++++++++ 3 files changed, 13 insertions(+), 1 deletion(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 1113dd4706ae..e03b85166e34 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1463,6 +1463,7 @@ extern struct pid *cad_pid; #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ #define PF_MEMALLOC_NOCMA 0x10000000 /* All allocation request will have _GFP_MOVABLE cleared */ +#define PF_CAN_BE_PACKED 0x20000000 /* Provide hints to the scheduler to pack such tasks */ #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ diff --git a/include/uapi/linux/sched.h b/include/uapi/linux/sched.h index 617bb59aa8ba..fccb1c57d037 100644 --- a/include/uapi/linux/sched.h +++ b/include/uapi/linux/sched.h @@ -55,6 +55,7 @@ #define SCHED_FLAG_KEEP_PARAMS 0x10 #define SCHED_FLAG_UTIL_CLAMP_MIN 0x20 #define SCHED_FLAG_UTIL_CLAMP_MAX 0x40 +#define SCHED_FLAG_TASK_PACKING 0x80 #define SCHED_FLAG_KEEP_ALL (SCHED_FLAG_KEEP_POLICY | \ SCHED_FLAG_KEEP_PARAMS) @@ -66,6 +67,7 @@ SCHED_FLAG_RECLAIM | \ SCHED_FLAG_DL_OVERRUN | \ SCHED_FLAG_KEEP_ALL | \ - SCHED_FLAG_UTIL_CLAMP) + SCHED_FLAG_UTIL_CLAMP | \ + SCHED_FLAG_TASK_PACKING) #endif /* _UAPI_LINUX_SCHED_H */ diff --git a/kernel/sched/core.c b/kernel/sched/core.c index fa43ce3962e7..e7cda4aa8696 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4498,6 +4498,8 @@ static void __setscheduler_params(struct task_struct *p, p->rt_priority = attr->sched_priority; p->normal_prio = normal_prio(p); set_load_weight(p, true); + if (attr->sched_flags & SCHED_FLAG_TASK_PACKING) + p->flags |= PF_CAN_BE_PACKED; } /* Actually do priority change: must hold pi & rq lock. */ @@ -4557,6 +4559,8 @@ static int __sched_setscheduler(struct task_struct *p, struct rq_flags rf; int reset_on_fork; int queue_flags = DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK; + unsigned long long task_packing_flag = + attr->sched_flags & SCHED_FLAG_TASK_PACKING; struct rq *rq; /* The pi code expects interrupts enabled */ @@ -4686,6 +4690,8 @@ static int __sched_setscheduler(struct task_struct *p, goto change; if (attr->sched_flags & SCHED_FLAG_UTIL_CLAMP) goto change; + if (task_packing_flag) + goto change; p->sched_reset_on_fork = reset_on_fork; task_rq_unlock(rq, p, &rf); @@ -5181,6 +5187,9 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr, attr.sched_util_max = p->uclamp_req[UCLAMP_MAX].value; #endif + if (p->flags & PF_CAN_BE_PACKED) + attr.sched_flags |= SCHED_FLAG_TASK_PACKING; + rcu_read_unlock(); retval = sched_read_attr(uattr, &attr, size); -- 2.17.1