linux-kernel - Re: [PATCH V8 2/2] firmware: qcom: scm: Add wait-queue handling logic

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Message-ID: <00e70137-3cc3-877e-5435-ac15f750f466@linaro.org>
Date:   Wed, 11 Jan 2023 16:01:58 +0000
From:   Srinivas Kandagatla <srinivas.kandagatla@...aro.org>
To:     Sibi Sankar <quic_sibis@...cinc.com>, andersson@...nel.org
Cc:     agross@...nel.org, linux-arm-msm@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        krzysztof.kozlowski+dt@...aro.org, robh+dt@...nel.org,
        konrad.dybcio@...ainline.org, robimarko@...il.com,
        quic_gurus@...cinc.com
Subject: Re: [PATCH V8 2/2] firmware: qcom: scm: Add wait-queue handling logic



On 11/01/2023 10:17, Sibi Sankar wrote:
> +static int qcom_scm_waitq_wakeup(struct qcom_scm *scm, unsigned int wq_ctx, bool wake_all)
> +{
> +	int ret;
> +
> +	ret = qcom_scm_assert_valid_wq_ctx(wq_ctx);
> +	if (ret)
> +		return ret;
> +
> +	if (wake_all)
> +		complete_all(&__scm->waitq_comp);

As you explained in v7 that there will be only one caller at any point 
in time and that will be synchronous, so complete_all here is a dead 
code, isn't it?

Adding complete_all here is missleading and will require reinit 
completion in case you want to reuse the same completion.

AFAIU, you should remove support to wake_all in this patchset and add it 
when we really can do multiple scm calls simultaneously.

--srini

--srini
> +	else
> +		complete(&__scm->waitq_comp);
> +