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Message-ID: <886f1a69-5688-196c-90f1-e1324e941e77@I-love.SAKURA.ne.jp>
Date:   Sat, 11 Jun 2022 07:51:42 +0900
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Subject: Re: [PATCH] ath6kl: avoid flush_scheduled_work() usage
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To:     Jeff Johnson <quic_jjohnson@quicinc.com>,
        Kalle Valo <kvalo@kernel.org>
Cc:     linux-wireless <linux-wireless@vger.kernel.org>
References: <8de85fd9-50a1-aad7-86f7-24834be8bbc0@I-love.SAKURA.ne.jp>
 <acb6a5e3-d349-76da-27fc-3377d3343dc0@quicinc.com>
 <376b3413-c584-192c-756d-609f7c55d742@quicinc.com>
From:   Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
In-Reply-To: <376b3413-c584-192c-756d-609f7c55d742@quicinc.com>
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Precedence: bulk

On 2022/06/11 4:10, Jeff Johnson wrote:
> On 6/10/2022 12:05 PM, Jeff Johnson wrote:
>>> +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.

Creating a WQ without WQ_MEM_RECLAIM flag consumes little resource.

>>
>> 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()?
> 
> typo: ath6kl_usb_pm_remove() => ath6kl_usb_remove()

Technically possible to use ath6kl_usb_create()/ath6kl_usb_destroy() if you prefer it.

Do you want ath6kl_wq be shared within this module (using a refcount), or be local to
each "struct ath6kl_usb" (adding a member and accessing via usb_get_intfdata()) ?