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Subject: Re: [PATCH 1/1] serial/uuc_uart: Set shutdown timeout to CONFIG_HZ
 independent 2ms
To: Alexander Stein <alexander.stein@systec-electronic.com>,
 Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Jiri Slaby <jslaby@suse.com>
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From: Timur Tabi <timur@tabi.org>
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Date: Mon, 5 Dec 2016 10:04:27 -0600
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Alexander Stein wrote:
> -		schedule_timeout(2);
> +		schedule_timeout(msecs_to_jiffies(2));

NACK.

So I don't remember why I wrote this code, but I don't think I was 
expecting it to be 2ms.  Instead, I think I just wanted it to be some 
delay, but I believed that schedule_timeout(1) was too short or would be 
"optimized" out somehow.

Note that right below this, I do:

	if (qe_port->wait_closing) {
		/* Wait a bit longer */
		set_current_state(TASK_UNINTERRUPTIBLE);
		schedule_timeout(qe_port->wait_closing);
	}

And wait_closing is a number of jiffies, so I knew that 
schedule_timeout() took jiffies as a parameter.

So I think I'm going to NACK this patch, since I believe I knew what I 
was doing when I wrote it five years ago.