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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date: Tue, 26 Mar 2024 09:07:58 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Shrikanth Hegde <sshegde@linux.ibm.com>
Cc: peterz@infradead.org, vincent.guittot@linaro.org,
	dietmar.eggemann@arm.com, qyousef@layalina.io,
	linux-kernel@vger.kernel.org, vschneid@redhat.com,
	joshdon@google.com, riel@surriel.com
Subject: Re: [PATCH] sched/fair: Simplify continue_balancing for newidle
Message-ID: <ZgKCXrUbBIxp6+mu@gmail.com>
References: <20240325153926.274284-1-sshegde@linux.ibm.com>
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* Shrikanth Hegde <sshegde@linux.ibm.com> wrote:

> newidle(CPU_NEWLY_IDLE) balancing doesn't stop the load balancing if the
> continue_balancing flag is reset. Other two balancing (IDLE, BUSY) do
> that. newidle balance stops the load balancing if rq has a task or there
> is wakeup pending. The same checks are present in should_we_balance for
> newidle. Hence use the return value and simplify continue_balancing
> mechanism for newidle. Update the comment surrounding it as well.

Assuming there are no side-effects to balancing behavior.

> No change in functionality intended.

Is this actually true? Any change to behavior invalidates such a sentence.

>  	/*
> +	 * We must set idle_stamp _before_ calling sched_balance_rq()
> +	 * for CPU_NEWLY_IDLE, such that we measure the this duration
> +	 * as idle time.
>  	 */

'the this' ...?

Thanks,

	Ingo