linux-kernel - [PATCH 06/10] sched/deadline: make GRUB a task's flag

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1495138417-6203-7-git-send-email-luca.abeni@santannapisa.it>
Date:   Thu, 18 May 2017 22:13:33 +0200
From:   luca abeni <luca.abeni@...tannapisa.it>
To:     linux-kernel@...r.kernel.org
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Juri Lelli <juri.lelli@....com>,
        Claudio Scordino <claudio@...dence.eu.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        Tommaso Cucinotta <tommaso.cucinotta@...up.it>,
        Daniel Bristot de Oliveira <bristot@...hat.com>,
        Joel Fernandes <joelaf@...gle.com>,
        Mathieu Poirier <mathieu.poirier@...aro.org>,
        Luca Abeni <luca.abeni@...tannapisa.it>
Subject: [PATCH 06/10] sched/deadline: make GRUB a task's flag

From: Luca Abeni <luca.abeni@...tannapisa.it>

This patch introduces the SCHED_FLAG_RECLAIM flag to specify
that a DL task is allowed to reclaim unused CPU time (using
the GRUB algorithm).

Signed-off-by: Luca Abeni <luca.abeni@...tannapisa.it>
Tested-by: Daniel Bristot de Oliveira <bristot@...hat.com>
---
 include/uapi/linux/sched.h | 1 +
 kernel/sched/core.c        | 3 ++-
 kernel/sched/deadline.c    | 3 ++-
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/include/uapi/linux/sched.h b/include/uapi/linux/sched.h
index 5f0fe01..e2a6c7b 100644
--- a/include/uapi/linux/sched.h
+++ b/include/uapi/linux/sched.h
@@ -47,5 +47,6 @@
  * For the sched_{set,get}attr() calls
  */
 #define SCHED_FLAG_RESET_ON_FORK	0x01
+#define SCHED_FLAG_RECLAIM		0x02
 
 #endif /* _UAPI_LINUX_SCHED_H */
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 84cd00f..7fcc3bd 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4207,7 +4207,8 @@ static int __sched_setscheduler(struct task_struct *p,
 			return -EINVAL;
 	}
 
-	if (attr->sched_flags & ~(SCHED_FLAG_RESET_ON_FORK))
+	if (attr->sched_flags &
+		~(SCHED_FLAG_RESET_ON_FORK | SCHED_FLAG_RECLAIM))
 		return -EINVAL;
 
 	/*
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index f4d36aa..0f545c1 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -985,7 +985,8 @@ static void update_curr_dl(struct rq *rq)
 
 	sched_rt_avg_update(rq, delta_exec);
 
-	delta_exec = grub_reclaim(delta_exec, rq);
+	if (unlikely(dl_se->flags & SCHED_FLAG_RECLAIM))
+		delta_exec = grub_reclaim(delta_exec, rq);
 	dl_se->runtime -= delta_exec;
 
 throttle:
-- 
2.7.4