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Subject: Re: [PATCH v1 1/4] coresight: etm4x: Add lock for reading virtual
 context ID comparator
To:     Leo Yan <leo.yan@linaro.org>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Mike Leach <mike.leach@linaro.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        James Clark <james.clark@arm.com>, coresight@lists.linaro.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20211031144214.237879-1-leo.yan@linaro.org>
 <20211031144214.237879-2-leo.yan@linaro.org>
From:   Suzuki K Poulose <suzuki.poulose@arm.com>
Message-ID: <df07c7b0-0145-8290-b4cd-a1831f19330d@arm.com>
Date:   Mon, 1 Nov 2021 09:49:06 +0000
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Hi Leo

On 31/10/2021 14:42, Leo Yan wrote:
> When read the virtual context ID comparator value via sysfs node, the
> driver firstly reads out the index, then reads the comparator value
> based on index. >
> This patch adds the spinlock to protect the atomicity for up two steps.

minor nit: This could be :

"Updates to the values and the index are protected via the
spinlock. Ensure we use the same lock to read the value
safely"

With that:

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>