netdev - Re: [PATCH v3 net] qed/qede: Fix scheduling while atomic

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Date:   Fri, 28 Apr 2023 10:26:51 -0700
From:   Stephen Hemminger <stephen@...workplumber.org>
To:     Manish Chopra <manishc@...vell.com>
Cc:     <kuba@...nel.org>, <netdev@...r.kernel.org>, <aelior@...vell.com>,
        <palok@...vell.com>, Sudarsana Kalluru <skalluru@...vell.com>,
        "David S . Miller" <davem@...emloft.net>
Subject: Re: [PATCH v3 net] qed/qede: Fix scheduling while atomic

On Fri, 28 Apr 2023 09:13:37 -0700
Manish Chopra <manishc@...vell.com> wrote:

> -		usleep_range(1000, 2000);
> +
> +		if (is_atomic)
> +			udelay(QED_BAR_ACQUIRE_TIMEOUT_UDELAY);
> +		else
> +			usleep_range(QED_BAR_ACQUIRE_TIMEOUT_USLEEP,
> +				     QED_BAR_ACQUIRE_TIMEOUT_USLEEP * 2);
>  	}

This is a variant of the conditional locking which is an ugly design pattern.
It makes static checking tools break and
a source of more bugs.

Better to fix the infrastructure or caller to not spin, or have two different
functions.