Re: [PATCH v33 3/7] sched/core: Activate blocked donor when no owner is found

[K Prateek Nayak <kprateek.nayak@amd.com>]

Hello Andrea,

On 10/24/2026 2:03 PM, Andrea Righi wrote:
>> @@ -7013,11 +7026,11 @@ find_proxy_task(struct rq *rq, struct task_struct *donor, struct rq_flags *rf)
>>  		struct mutex *mutex = p->blocked_on;
>>  		if (!mutex) {
>>  			clear_task_blocked_on(p, mutex);
>> -			if (task_current(rq, p)) {
>> +			if (task_current(rq, p) || p->wake_cpu == task_cpu(p)) {
>>  				p->is_blocked = 0;
>>  				return p;
>>  			}
>> -			goto deactivate;
>> +			goto activate;
>>  		}
> 
> IIUC, p here isn't necessarily the donor, after the first iteration it
> can be an intermediate owner that is queued on this rq and blocked
> itself. If its blocked_on was cleared by a handoff (or its mutex has no
> owner, below), we now return it when p->wake_cpu == task_cpu(p),
> skipping the sched_cpu_cookie_match() check at the end of the function.
> 
> So with CONFIG_SCHED_CORE enabled, are we running a task that was never
> cookie-checked by the core-wide pick?

You are right! I guess we should consolidate all the "return p" bits
to jump to the sched_cpu_cookie_match() check.

-- 
Thanks and Regards,
Prateek