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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date: Mon, 25 Mar 2024 11:36:36 +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
Subject: Re: [PATCH v3 0/2] sched: Minor changes for rd->overload access
Message-ID: <ZgFTtAOw39tIyfzR@gmail.com>
References: <20240325054505.201995-1-sshegde@linux.ibm.com>
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* Shrikanth Hegde <sshegde@linux.ibm.com> wrote:

> v2 -> v3:
> - Wrapped check for value change inside ser_rd_overload_status
>   as suggested by Qais.
> - Added reviewed-by tags.
> 
> v1 -> v2:
> - dropped Fixes tag.
> - Added one of the perf probes in the changelog for reference.
> - Added reviewed-by tags.
> 
> tl;dr
> When running workloads in large systems, it was observed that access to
> rd->overload was taking time. It would be better to check the value
> before updating since value changes less often. Patch 1/2 does that.
> With patch updates happen only if necessary. CPU Bus traffic reduced a
> bit. No significant gains in workload performance.

Could you please post this against the latest scheduler tree, ie. tip:sched/core?

Thanks,

	Ingo