Re: [PATCH 1/6] sched: migration changes for core scheduling

[Li, Aubrey]

On 2021/3/22 20:56, Peter Zijlstra wrote:
> On Mon, Mar 22, 2021 at 08:31:09PM +0800, Li, Aubrey wrote:
>> Please let me know if I put cookie match check at the right position
>> in task_hot(), if so, I'll obtain some performance data of it.
>>
>> Thanks,
>> -Aubrey
>>
>> =======================================================
>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
>> index 7f2fb08..d4bdcf9 100644
>> --- a/kernel/sched/fair.c
>> +++ b/kernel/sched/fair.c
>> @@ -1912,6 +1912,13 @@ static void task_numa_find_cpu(struct task_numa_env *env,
>>  		if (!cpumask_test_cpu(cpu, env->p->cpus_ptr))
>>  			continue;
>>  
>> +		/*
>> +		 * Skip this cpu if source task's cookie does not match
>> +		 * with CPU's core cookie.
>> +		 */
>> +		if (!sched_core_cookie_match(cpu_rq(cpu), env->p))
>> +			continue;
>> +
>>  		env->dst_cpu = cpu;
>>  		if (task_numa_compare(env, taskimp, groupimp, maymove))
>>  			break;
> 
> This one might need a little help too, I've not fully considered NUMA
> balancing though.
> 
I dropped this numa change for now as it may be too strong, too. I'll
do more experiment about this on the new iteration.

The following patch is rebased on top of queue tree, cookie check is moved
from can_migrate_task to task_hot.

please let me know if any issues.

Thanks,
-Aubrey
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