Re: [RFC PATCH 04/10] sched: Introduce priority-based task migration filter

2012-10-24 Thread li guang
在 2012-10-09二的 17:40 +0100,Morten Rasmussen写道:
 On Thu, Oct 04, 2012 at 07:27:00AM +0100, Viresh Kumar wrote:
  On 22 September 2012 00:02,  morten.rasmus...@arm.com wrote:
  
   +config SCHED_HMP_PRIO_FILTER
   +   bool (EXPERIMENTAL) Filter HMP migrations by task priority
   +   depends on SCHED_HMP
  
  Should it depend on EXPERIMENTAL?
  
   +   help
   + Enables task priority based HMP migration filter. Any task with
   + a NICE value above the threshold will always be on low-power 
   cpus
   + with less compute capacity.
   +
   +config SCHED_HMP_PRIO_FILTER_VAL
   +   int NICE priority threshold
   +   default 5
   +   depends on SCHED_HMP_PRIO_FILTER
   +
config HAVE_ARM_SCU
   bool
   help
   diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
   index 490f1f0..8f0f3b9 100644
   --- a/kernel/sched/fair.c
   +++ b/kernel/sched/fair.c
   @@ -3129,9 +3129,12 @@ static int __init hmp_cpu_mask_setup(void)
 * hmp_down_threshold: max. load allowed for tasks migrating to a slower 
   cpu
 * The default values (512, 256) offer good responsiveness, but may need
 * tweaking suit particular needs.
   + *
   + * hmp_up_prio: Only up migrate task with high priority (hmp_up_prio)
 */
unsigned int hmp_up_threshold = 512;
unsigned int hmp_down_threshold = 256;

hmp_*_threshold maybe sysctl_hmp_*_threshold,
and appear at /proc/sys/kernel,
so, can be adjusted to be rational.

   +unsigned int hmp_up_prio = 
   NICE_TO_PRIO(CONFIG_SCHED_HMP_PRIO_FILTER_VAL);
  
static unsigned int hmp_up_migration(int cpu, struct sched_entity *se);
static unsigned int hmp_down_migration(int cpu, struct sched_entity *se);
   @@ -5491,6 +5494,12 @@ static unsigned int hmp_up_migration(int cpu, 
   struct sched_entity *se)
   if (hmp_cpu_is_fastest(cpu))
   return 0;
  
   +#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
   +   /* Filter by task priority */
   +   if (p-prio = hmp_up_prio)
   +   return 0;
   +#endif
   +
   if (cpumask_intersects(hmp_faster_domain(cpu)-cpus,
   tsk_cpus_allowed(p))
se-avg.load_avg_ratio  hmp_up_threshold) {
   @@ -5507,6 +5516,12 @@ static unsigned int hmp_down_migration(int cpu, 
   struct sched_entity *se)
   if (hmp_cpu_is_slowest(cpu))
   return 0;
  
   +#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
   +   /* Filter by task priority */
   +   if (p-prio = hmp_up_prio)
   +   return 1;
   +#endif
  
  Even if below cpumask_intersects() fails?
  
 
 No. Good catch :)
 
   if (cpumask_intersects(hmp_slower_domain(cpu)-cpus,
   tsk_cpus_allowed(p))
se-avg.load_avg_ratio  hmp_down_threshold) {
  
  --
  viresh
  
 
 Thanks,
 Morten
 
 --
 To unsubscribe from this list: send the line unsubscribe linux-kernel in
 the body of a message to majord...@vger.kernel.org
 More majordomo info at  http://vger.kernel.org/majordomo-info.html
 Please read the FAQ at  http://www.tux.org/lkml/

-- 
liguanglig.f...@cn.fujitsu.com
FNST linux kernel team


___
linaro-dev mailing list
linaro-dev@lists.linaro.org
http://lists.linaro.org/mailman/listinfo/linaro-dev


Re: [RFC PATCH 04/10] sched: Introduce priority-based task migration filter

2012-10-09 Thread Morten Rasmussen
On Thu, Oct 04, 2012 at 07:27:00AM +0100, Viresh Kumar wrote:
 On 22 September 2012 00:02,  morten.rasmus...@arm.com wrote:
 
  +config SCHED_HMP_PRIO_FILTER
  +   bool (EXPERIMENTAL) Filter HMP migrations by task priority
  +   depends on SCHED_HMP
 
 Should it depend on EXPERIMENTAL?
 
  +   help
  + Enables task priority based HMP migration filter. Any task with
  + a NICE value above the threshold will always be on low-power cpus
  + with less compute capacity.
  +
  +config SCHED_HMP_PRIO_FILTER_VAL
  +   int NICE priority threshold
  +   default 5
  +   depends on SCHED_HMP_PRIO_FILTER
  +
   config HAVE_ARM_SCU
  bool
  help
  diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
  index 490f1f0..8f0f3b9 100644
  --- a/kernel/sched/fair.c
  +++ b/kernel/sched/fair.c
  @@ -3129,9 +3129,12 @@ static int __init hmp_cpu_mask_setup(void)
* hmp_down_threshold: max. load allowed for tasks migrating to a slower 
  cpu
* The default values (512, 256) offer good responsiveness, but may need
* tweaking suit particular needs.
  + *
  + * hmp_up_prio: Only up migrate task with high priority (hmp_up_prio)
*/
   unsigned int hmp_up_threshold = 512;
   unsigned int hmp_down_threshold = 256;
  +unsigned int hmp_up_prio = NICE_TO_PRIO(CONFIG_SCHED_HMP_PRIO_FILTER_VAL);
 
   static unsigned int hmp_up_migration(int cpu, struct sched_entity *se);
   static unsigned int hmp_down_migration(int cpu, struct sched_entity *se);
  @@ -5491,6 +5494,12 @@ static unsigned int hmp_up_migration(int cpu, struct 
  sched_entity *se)
  if (hmp_cpu_is_fastest(cpu))
  return 0;
 
  +#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
  +   /* Filter by task priority */
  +   if (p-prio = hmp_up_prio)
  +   return 0;
  +#endif
  +
  if (cpumask_intersects(hmp_faster_domain(cpu)-cpus,
  tsk_cpus_allowed(p))
   se-avg.load_avg_ratio  hmp_up_threshold) {
  @@ -5507,6 +5516,12 @@ static unsigned int hmp_down_migration(int cpu, 
  struct sched_entity *se)
  if (hmp_cpu_is_slowest(cpu))
  return 0;
 
  +#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
  +   /* Filter by task priority */
  +   if (p-prio = hmp_up_prio)
  +   return 1;
  +#endif
 
 Even if below cpumask_intersects() fails?
 

No. Good catch :)

  if (cpumask_intersects(hmp_slower_domain(cpu)-cpus,
  tsk_cpus_allowed(p))
   se-avg.load_avg_ratio  hmp_down_threshold) {
 
 --
 viresh
 

Thanks,
Morten


___
linaro-dev mailing list
linaro-dev@lists.linaro.org
http://lists.linaro.org/mailman/listinfo/linaro-dev


[RFC PATCH 04/10] sched: Introduce priority-based task migration filter

2012-09-21 Thread morten . rasmussen
From: Morten Rasmussen morten.rasmus...@arm.com

Introduces a priority threshold which prevents low priority task
from migrating to faster hmp_domains (cpus). This is useful for
user-space software which assigns lower task priority to background
task.

Signed-off-by: Morten Rasmussen morten.rasmus...@arm.com
---
 arch/arm/Kconfig|   13 +
 kernel/sched/fair.c |   15 +++
 2 files changed, 28 insertions(+)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 5b09684..05de193 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1571,6 +1571,19 @@ config SCHED_HMP
  !SCHED_AUTOGROUP. Furthermore, normal load-balancing must be disabled
  between cpus of different type (DISABLE_CPU_SCHED_DOMAIN_BALANCE).
 
+config SCHED_HMP_PRIO_FILTER
+   bool (EXPERIMENTAL) Filter HMP migrations by task priority
+   depends on SCHED_HMP
+   help
+ Enables task priority based HMP migration filter. Any task with
+ a NICE value above the threshold will always be on low-power cpus
+ with less compute capacity.
+
+config SCHED_HMP_PRIO_FILTER_VAL
+   int NICE priority threshold
+   default 5
+   depends on SCHED_HMP_PRIO_FILTER
+
 config HAVE_ARM_SCU
bool
help
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 490f1f0..8f0f3b9 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3129,9 +3129,12 @@ static int __init hmp_cpu_mask_setup(void)
  * hmp_down_threshold: max. load allowed for tasks migrating to a slower cpu
  * The default values (512, 256) offer good responsiveness, but may need
  * tweaking suit particular needs.
+ *
+ * hmp_up_prio: Only up migrate task with high priority (hmp_up_prio)
  */
 unsigned int hmp_up_threshold = 512;
 unsigned int hmp_down_threshold = 256;
+unsigned int hmp_up_prio = NICE_TO_PRIO(CONFIG_SCHED_HMP_PRIO_FILTER_VAL);
 
 static unsigned int hmp_up_migration(int cpu, struct sched_entity *se);
 static unsigned int hmp_down_migration(int cpu, struct sched_entity *se);
@@ -5491,6 +5494,12 @@ static unsigned int hmp_up_migration(int cpu, struct 
sched_entity *se)
if (hmp_cpu_is_fastest(cpu))
return 0;
 
+#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
+   /* Filter by task priority */
+   if (p-prio = hmp_up_prio)
+   return 0;
+#endif
+
if (cpumask_intersects(hmp_faster_domain(cpu)-cpus,
tsk_cpus_allowed(p))
 se-avg.load_avg_ratio  hmp_up_threshold) {
@@ -5507,6 +5516,12 @@ static unsigned int hmp_down_migration(int cpu, struct 
sched_entity *se)
if (hmp_cpu_is_slowest(cpu))
return 0;
 
+#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
+   /* Filter by task priority */
+   if (p-prio = hmp_up_prio)
+   return 1;
+#endif
+
if (cpumask_intersects(hmp_slower_domain(cpu)-cpus,
tsk_cpus_allowed(p))
 se-avg.load_avg_ratio  hmp_down_threshold) {
-- 
1.7.9.5



___
linaro-dev mailing list
linaro-dev@lists.linaro.org
http://lists.linaro.org/mailman/listinfo/linaro-dev