Re: [patch 15/16] sched: implement usage tracking
Hi Paul,
I think that you have forgot to reset .usage_avg_sum in the
__sched_fork as it's already done for .runnable_avg_sum and
.usage_avg_sum
And it seems that this reset is not corrected in the latest version in
your git repo:
http://git.kernel.org/?p=linux/kernel/git/pjt/sched.git;a=blob;f=kernel/sched/core.c;h=df55e2ecdd2398648c7d01e318070d06b845a5b0;hb=refs/heads/load_tracking#l1535
Regards,
Vincent
On 23 August 2012 16:14, wrote:
> From: Paul Turner
>
> With the frame-work for runnable tracking now fully in place. Per-entity
> usage
> tracking is a simple and low-overhead addition.
>
> Signed-off-by: Paul Turner
> Reviewed-by: Ben Segall
> ---
> include/linux/sched.h |1 +
> kernel/sched/debug.c |3 +++
> kernel/sched/fair.c | 33 -
> kernel/sched/sched.h |4 ++--
> 4 files changed, 34 insertions(+), 7 deletions(-)
>
> diff --git a/include/linux/sched.h b/include/linux/sched.h
> index 93e27c0..2a4be1f 100644
> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -1150,6 +1150,7 @@ struct sched_avg {
> u64 last_runnable_update;
> s64 decay_count;
> unsigned long load_avg_contrib;
> + u32 usage_avg_sum;
> };
>
> #ifdef CONFIG_SCHEDSTATS
> diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
> index 2cd3c1b..b9d54d0 100644
> --- a/kernel/sched/debug.c
> +++ b/kernel/sched/debug.c
> @@ -94,6 +94,7 @@ static void print_cfs_group_stats(struct seq_file *m, int
> cpu, struct task_group
> #ifdef CONFIG_SMP
> P(se->avg.runnable_avg_sum);
> P(se->avg.runnable_avg_period);
> + P(se->avg.usage_avg_sum);
> P(se->avg.load_avg_contrib);
> P(se->avg.decay_count);
> #endif
> @@ -230,6 +231,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct
> cfs_rq *cfs_rq)
> cfs_rq->tg_runnable_contrib);
> SEQ_printf(m, " .%-30s: %d\n", "tg->runnable_avg",
> atomic_read(_rq->tg->runnable_avg));
> + SEQ_printf(m, " .%-30s: %d\n", "tg->usage_avg",
> + atomic_read(_rq->tg->usage_avg));
> #endif
>
> print_cfs_group_stats(m, cpu, cfs_rq->tg);
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index b249371..44a9a11 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -994,7 +994,8 @@ static u32 __compute_runnable_contrib(u64 n)
> */
> static __always_inline int __update_entity_runnable_avg(u64 now,
> struct sched_avg *sa,
> - int runnable)
> + int runnable,
> + int running)
> {
> u64 delta, periods;
> u32 runnable_contrib;
> @@ -1033,6 +1034,8 @@ static __always_inline int
> __update_entity_runnable_avg(u64 now,
> delta_w = 1024 - delta_w;
> if (runnable)
> sa->runnable_avg_sum += delta_w;
> + if (running)
> + sa->usage_avg_sum += delta_w;
> sa->runnable_avg_period += delta_w;
>
> delta -= delta_w;
> @@ -1045,17 +1048,22 @@ static __always_inline int
> __update_entity_runnable_avg(u64 now,
> periods + 1);
> sa->runnable_avg_period = decay_load(sa->runnable_avg_period,
> periods + 1);
> + sa->usage_avg_sum = decay_load(sa->usage_avg_sum, periods +
> 1);
>
> /* Efficiently calculate \sum (1..n_period) 1024*y^i */
> runnable_contrib = __compute_runnable_contrib(periods);
> if (runnable)
> sa->runnable_avg_sum += runnable_contrib;
> + if (running)
> + sa->usage_avg_sum += runnable_contrib;
> sa->runnable_avg_period += runnable_contrib;
> }
>
> /* Remainder of delta accrued against u_0` */
> if (runnable)
> sa->runnable_avg_sum += delta;
> + if (running)
> + sa->usage_avg_sum += delta;
> sa->runnable_avg_period += delta;
>
> return decayed;
> @@ -1101,16 +1109,28 @@ static inline void __update_tg_runnable_avg(struct
> sched_avg *sa,
> struct cfs_rq *cfs_rq)
> {
> struct task_group *tg = cfs_rq->tg;
> - long contrib;
> + long contrib, usage_contrib;
>
> /* The fraction of a cpu used by this cfs_rq */
> contrib = div_u64(sa->runnable_avg_sum << NICE_0_SHIFT,
> sa->runnable_avg_period + 1);
> contrib -= cfs_rq->tg_runnable_contrib;
>
> - if (abs(contrib) > cfs_rq->tg_runnable_contrib / 64) {
> + usage_contrib = div_u64(sa->usage_avg_sum << NICE_0_SHIFT,
> +
Re: [patch 15/16] sched: implement usage tracking
Hi Paul,
I think that you have forgot to reset .usage_avg_sum in the
__sched_fork as it's already done for .runnable_avg_sum and
.usage_avg_sum
And it seems that this reset is not corrected in the latest version in
your git repo:
http://git.kernel.org/?p=linux/kernel/git/pjt/sched.git;a=blob;f=kernel/sched/core.c;h=df55e2ecdd2398648c7d01e318070d06b845a5b0;hb=refs/heads/load_tracking#l1535
Regards,
Vincent
On 23 August 2012 16:14, p...@google.com wrote:
From: Paul Turner p...@google.com
With the frame-work for runnable tracking now fully in place. Per-entity
usage
tracking is a simple and low-overhead addition.
Signed-off-by: Paul Turner p...@google.com
Reviewed-by: Ben Segall bseg...@google.com
---
include/linux/sched.h |1 +
kernel/sched/debug.c |3 +++
kernel/sched/fair.c | 33 -
kernel/sched/sched.h |4 ++--
4 files changed, 34 insertions(+), 7 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 93e27c0..2a4be1f 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1150,6 +1150,7 @@ struct sched_avg {
u64 last_runnable_update;
s64 decay_count;
unsigned long load_avg_contrib;
+ u32 usage_avg_sum;
};
#ifdef CONFIG_SCHEDSTATS
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 2cd3c1b..b9d54d0 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -94,6 +94,7 @@ static void print_cfs_group_stats(struct seq_file *m, int
cpu, struct task_group
#ifdef CONFIG_SMP
P(se-avg.runnable_avg_sum);
P(se-avg.runnable_avg_period);
+ P(se-avg.usage_avg_sum);
P(se-avg.load_avg_contrib);
P(se-avg.decay_count);
#endif
@@ -230,6 +231,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct
cfs_rq *cfs_rq)
cfs_rq-tg_runnable_contrib);
SEQ_printf(m, .%-30s: %d\n, tg-runnable_avg,
atomic_read(cfs_rq-tg-runnable_avg));
+ SEQ_printf(m, .%-30s: %d\n, tg-usage_avg,
+ atomic_read(cfs_rq-tg-usage_avg));
#endif
print_cfs_group_stats(m, cpu, cfs_rq-tg);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index b249371..44a9a11 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -994,7 +994,8 @@ static u32 __compute_runnable_contrib(u64 n)
*/
static __always_inline int __update_entity_runnable_avg(u64 now,
struct sched_avg *sa,
- int runnable)
+ int runnable,
+ int running)
{
u64 delta, periods;
u32 runnable_contrib;
@@ -1033,6 +1034,8 @@ static __always_inline int
__update_entity_runnable_avg(u64 now,
delta_w = 1024 - delta_w;
if (runnable)
sa-runnable_avg_sum += delta_w;
+ if (running)
+ sa-usage_avg_sum += delta_w;
sa-runnable_avg_period += delta_w;
delta -= delta_w;
@@ -1045,17 +1048,22 @@ static __always_inline int
__update_entity_runnable_avg(u64 now,
periods + 1);
sa-runnable_avg_period = decay_load(sa-runnable_avg_period,
periods + 1);
+ sa-usage_avg_sum = decay_load(sa-usage_avg_sum, periods +
1);
/* Efficiently calculate \sum (1..n_period) 1024*y^i */
runnable_contrib = __compute_runnable_contrib(periods);
if (runnable)
sa-runnable_avg_sum += runnable_contrib;
+ if (running)
+ sa-usage_avg_sum += runnable_contrib;
sa-runnable_avg_period += runnable_contrib;
}
/* Remainder of delta accrued against u_0` */
if (runnable)
sa-runnable_avg_sum += delta;
+ if (running)
+ sa-usage_avg_sum += delta;
sa-runnable_avg_period += delta;
return decayed;
@@ -1101,16 +1109,28 @@ static inline void __update_tg_runnable_avg(struct
sched_avg *sa,
struct cfs_rq *cfs_rq)
{
struct task_group *tg = cfs_rq-tg;
- long contrib;
+ long contrib, usage_contrib;
/* The fraction of a cpu used by this cfs_rq */
contrib = div_u64(sa-runnable_avg_sum NICE_0_SHIFT,
sa-runnable_avg_period + 1);
contrib -= cfs_rq-tg_runnable_contrib;
- if (abs(contrib) cfs_rq-tg_runnable_contrib / 64) {
+ usage_contrib = div_u64(sa-usage_avg_sum NICE_0_SHIFT,
+ sa-runnable_avg_period + 1);
+ usage_contrib -=
