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Date: Wed, 20 Dec 2023 15:05:01 -0800
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Subject: Re: [PATCH V2 01/12 net-next] qca_spi: Improve SPI thread creation
Content-Language: en-US
To: Stefan Wahren <wahrenst@gmx.net>, "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>, Jakub Kicinski <kuba@kernel.org>, "Paolo
 Abeni" <pabeni@redhat.com>
CC: <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20231218232639.33327-1-wahrenst@gmx.net>
 <20231218232639.33327-2-wahrenst@gmx.net>
From: Jacob Keller <jacob.e.keller@intel.com>
In-Reply-To: <20231218232639.33327-2-wahrenst@gmx.net>
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On 12/18/2023 3:26 PM, Stefan Wahren wrote:
> The qca_spi driver create/stop the SPI kernel thread in case
> of netdev_open/close. This isn't optimal because there is no
> need for such an expensive operation.
> 
> So improve this by moving create/stop of the SPI kernel into
> the init/uninit ops. The open/close ops could just
> 'park/unpark' the SPI kernel thread.
> 

If I understand, this is also important because kthread_stop would
ultimately result in the task being destroyed and thus user space
configuration of the task (priority, pinning, etc) would be lost too.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>