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Message-ID: <acb6a5e3-d349-76da-27fc-3377d3343dc0@quicinc.com>
Date:   Fri, 10 Jun 2022 12:05:14 -0700
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Subject: Re: [PATCH] ath6kl: avoid flush_scheduled_work() usage
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To:     Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
        Kalle Valo <kvalo@kernel.org>
CC:     linux-wireless <linux-wireless@vger.kernel.org>
References: <8de85fd9-50a1-aad7-86f7-24834be8bbc0@I-love.SAKURA.ne.jp>
From:   Jeff Johnson <quic_jjohnson@quicinc.com>
In-Reply-To: <8de85fd9-50a1-aad7-86f7-24834be8bbc0@I-love.SAKURA.ne.jp>
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On 6/10/2022 4:12 AM, Tetsuo Handa wrote:
> Use local wq in order to avoid flush_scheduled_work() usage.
> 
> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> ---
> Please see commit c4f135d643823a86 ("workqueue: Wrap flush_workqueue()
> using a macro") for background.
> 
> This is a blind conversion, and is only compile tested.
> 
>   drivers/net/wireless/ath/ath6kl/usb.c | 29 +++++++++++++++++++++++----
>   1 file changed, 25 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath6kl/usb.c b/drivers/net/wireless/ath/ath6kl/usb.c
[snip]
> -module_usb_driver(ath6kl_usb_driver);
> +static int __init ath6kl_init(void)
> +{
> +	int ret;
> +
> +	ath6kl_wq = alloc_workqueue("ath6kl_wq", 0, 0);
> +	if (!ath6kl_wq)
> +		return -ENOMEM;

this approach means the driver will always allocate a workqueue even if 
the associated hardware is never present.

did you consider instead having the allocation take place within the 
processing of ath6kl_usb_probe() and the destroy take place within the 
processing of ath6kl_usb_pm_remove()?