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From:   Will Deacon <will@kernel.org>
To:     mark.rutland@arm.com, Robin Murphy <robin.murphy@arm.com>
Cc:     catalin.marinas@arm.com, kernel-team@android.com,
        Will Deacon <will@kernel.org>, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] perf/arm-cmn: Reset DTM_PMU_CONFIG at probe
Date:   Thu, 19 Jan 2023 19:08:43 +0000
Message-Id: <167415190277.3429004.658905197029681030.b4-ty@kernel.org>
In-Reply-To: <ba5f38b3dc733cd06bfb5e659b697e76d18c2183.1670269572.git.robin.murphy@arm.com>
References: <ba5f38b3dc733cd06bfb5e659b697e76d18c2183.1670269572.git.robin.murphy@arm.com>
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On Mon, 5 Dec 2022 19:46:13 +0000, Robin Murphy wrote:
> Although we treat the DTM counters as free-running such that we're not
> too concerned about the initial DTM state, it's possible for a previous
> user to have left DTM counters enabled and paired with DTC counters.
> Thus if the first events are scheduled using some, but not all, DTMs,
> the as-yet-unused ones could end up adding spurious increments to the
> event counts at the DTC. Make sure we sync our initial DTM_PMU_CONFIG
> state to all the DTMs at probe time to avoid that possibility.
> 
> [...]

Applied to will (for-next/perf), thanks!

[1/1] perf/arm-cmn: Reset DTM_PMU_CONFIG at probe
      https://git.kernel.org/will/c/bb21ef19a3d8

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev