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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Morten Helgesen <morten@sourcepoet.org>
Cc: akpm@osdl.org, linux-kernel@vger.kernel.org,
	linux-serial@vger.kernel.org
Subject: Re: [PATCH] genericserial: Remove bogus optimisation check and dead code paths
Date: Tue, 3 Jul 2007 23:31:35 +0100	[thread overview]
Message-ID: <20070703233135.502bba84@the-village.bc.nu> (raw)
In-Reply-To: <468AC156.5040402@sourcepoet.org>

On Tue, 03 Jul 2007 23:36:22 +0200
Morten Helgesen <morten@sourcepoet.org> wrote:


>  /*
>  > Problems to take into account are:
>  >       -1- Interrupts that empty part of the buffer.
> ->       -2- page faults on the access to userspace. 
> +>       -2- Page faults on access to userspace. 

#2 no longer applies (don't before the caller)
>  >       -3- Other processes that are also trying to do a "write".   
#3 no longer applies (locked by tty layer)

> -	/* get exclusive "write" access to this port (problem 3) */
> +	/* Get exclusive "write" access to this port (problem 3) */
>  	/* This is not a spinlock because we can have a disk access (page 
> -		 fault) in copy_from_user */

No copy_from_user any more. Actually that locking code wants review and
maybe removal so is another project altogether


Definitely an improvement

Acked-by: Alan Cox <alan@redhat.com>

      reply	other threads:[~2007-07-03 22:25 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-07-03 14:20 Alan Cox
2007-07-03 14:39 ` Morten Helgesen
2007-07-03 15:26   ` Alan Cox
2007-07-03 21:33     ` Morten Helgesen
2007-07-03 21:36     ` Morten Helgesen
2007-07-03 22:31       ` Alan Cox [this message]

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