diff options
| author | Luca Abeni <luca.abeni@santannapisa.it> | 2017-05-18 22:13:29 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-06-08 10:31:49 +0200 |
| commit | 209a0cbda7a01d2ea32a8b631d35e873bee498e9 (patch) | |
| tree | 68e22c41537d48bb1d1f26e5e26c59f7a4bb2013 /include/linux/sched.h | |
| parent | e36d8677bfa55054e4194ec3683189b882a538f6 (diff) | |
sched/deadline: Improve the tracking of active utilization
This patch implements a more theoretically sound algorithm for
tracking active utilization: instead of decreasing it when a
task blocks, use a timer (the "inactive timer", named after the
"Inactive" task state of the GRUB algorithm) to decrease the
active utilization at the so called "0-lag time".
Tested-by: Claudio Scordino <claudio@evidence.eu.com>
Tested-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Luca Abeni <luca.abeni@santannapisa.it>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tommaso Cucinotta <tommaso.cucinotta@sssup.it>
Link: http://lkml.kernel.org/r/1495138417-6203-3-git-send-email-luca.abeni@santannapisa.it
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/linux/sched.h')
| -rw-r--r-- | include/linux/sched.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index 1abaa3728bf7..f1ead2e88d3d 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -445,16 +445,33 @@ struct sched_dl_entity { * * @dl_yielded tells if task gave up the CPU before consuming * all its available runtime during the last job. + * + * @dl_non_contending tells if the task is inactive while still + * contributing to the active utilization. In other words, it + * indicates if the inactive timer has been armed and its handler + * has not been executed yet. This flag is useful to avoid race + * conditions between the inactive timer handler and the wakeup + * code. */ int dl_throttled; int dl_boosted; int dl_yielded; + int dl_non_contending; /* * Bandwidth enforcement timer. Each -deadline task has its * own bandwidth to be enforced, thus we need one timer per task. */ struct hrtimer dl_timer; + + /* + * Inactive timer, responsible for decreasing the active utilization + * at the "0-lag time". When a -deadline task blocks, it contributes + * to GRUB's active utilization until the "0-lag time", hence a + * timer is needed to decrease the active utilization at the correct + * time. + */ + struct hrtimer inactive_timer; }; union rcu_special { |