| 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
| ||
|
Date: Fri, 18 Nov 2011 16:18:22 +0100
From: Mike Galbraith <efault@....de>
To: Suresh Siddha <suresh.b.siddha@...el.com>
Cc: Peter Zijlstra <peterz@...radead.org>,
linux-kernel <linux-kernel@...r.kernel.org>,
Ingo Molnar <mingo@...e.hu>, Paul Turner <pjt@...gle.com>
Subject: [patch 2/6] sched: convert rq->avg_idle to rq->avg_event
We update rq->clock only at points of interest to the scheduler.
Using this distance has the same effect as measuring idle time
for idle_balance() throttling, and allows other uses as well.
Signed-off-by: Mike Galbraith <efault@....de>
---
kernel/sched.c | 32 +++++++++++---------------------
kernel/sched_debug.c | 2 +-
kernel/sched_fair.c | 8 ++------
3 files changed, 14 insertions(+), 28 deletions(-)
Index: linux-3.2.git/kernel/sched.c
===================================================================
--- linux-3.2.git.orig/kernel/sched.c
+++ linux-3.2.git/kernel/sched.c
@@ -656,8 +656,7 @@ struct rq {
u64 rt_avg;
u64 age_stamp;
- u64 idle_stamp;
- u64 avg_idle;
+ u64 avg_event;
#endif
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
@@ -789,6 +788,14 @@ static inline struct task_group *task_gr
#endif /* CONFIG_CGROUP_SCHED */
+static void update_avg(u64 *avg, u64 sample)
+{
+#ifdef CONFIG_SMP
+ s64 diff = sample - *avg;
+ *avg += diff >> 3;
+#endif
+}
+
static void update_rq_clock_task(struct rq *rq, s64 delta);
static void update_rq_clock(struct rq *rq)
@@ -801,6 +808,7 @@ static void update_rq_clock(struct rq *r
delta = sched_clock_cpu(cpu_of(rq)) - rq->clock;
rq->clock += delta;
update_rq_clock_task(rq, delta);
+ update_avg(&rq->avg_event, delta);
}
/*
@@ -2593,12 +2601,6 @@ int select_task_rq(struct task_struct *p
return cpu;
}
-
-static void update_avg(u64 *avg, u64 sample)
-{
- s64 diff = sample - *avg;
- *avg += diff >> 3;
-}
#endif
static void
@@ -2664,17 +2666,6 @@ ttwu_do_wakeup(struct rq *rq, struct tas
#ifdef CONFIG_SMP
if (p->sched_class->task_woken)
p->sched_class->task_woken(rq, p);
-
- if (rq->idle_stamp) {
- u64 delta = rq->clock - rq->idle_stamp;
- u64 max = 2*sysctl_sched_migration_cost;
-
- if (delta > max)
- rq->avg_idle = max;
- else
- update_avg(&rq->avg_idle, delta);
- rq->idle_stamp = 0;
- }
#endif
}
@@ -8294,8 +8285,7 @@ void __init sched_init(void)
rq->push_cpu = 0;
rq->cpu = i;
rq->online = 0;
- rq->idle_stamp = 0;
- rq->avg_idle = 2*sysctl_sched_migration_cost;
+ rq->avg_event = 0;
rq_attach_root(rq, &def_root_domain);
#ifdef CONFIG_NO_HZ
rq->nohz_balance_kick = 0;
Index: linux-3.2.git/kernel/sched_debug.c
===================================================================
--- linux-3.2.git.orig/kernel/sched_debug.c
+++ linux-3.2.git/kernel/sched_debug.c
@@ -290,7 +290,7 @@ static void print_cpu(struct seq_file *m
P(sched_count);
P(sched_goidle);
#ifdef CONFIG_SMP
- P64(avg_idle);
+ P64(avg_event);
#endif
P(ttwu_count);
Index: linux-3.2.git/kernel/sched_fair.c
===================================================================
--- linux-3.2.git.orig/kernel/sched_fair.c
+++ linux-3.2.git/kernel/sched_fair.c
@@ -4190,9 +4190,7 @@ static void idle_balance(int this_cpu, s
int pulled_task = 0;
unsigned long next_balance = jiffies + HZ;
- this_rq->idle_stamp = this_rq->clock;
-
- if (this_rq->avg_idle < sysctl_sched_migration_cost)
+ if (this_rq->avg_event < sysctl_sched_migration_cost)
return;
/*
@@ -4218,10 +4216,8 @@ static void idle_balance(int this_cpu, s
interval = msecs_to_jiffies(sd->balance_interval);
if (time_after(next_balance, sd->last_balance + interval))
next_balance = sd->last_balance + interval;
- if (pulled_task) {
- this_rq->idle_stamp = 0;
+ if (pulled_task)
break;
- }
}
rcu_read_unlock();
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists