Re: [PATCH] genericserial: Remove bogus optimisation check and deadcode paths

From: Alan Cox
Date: Tue Jul 03 2007 - 18:25:30 EST


On Tue, 03 Jul 2007 23:36:22 +0200
Morten Helgesen <morten@xxxxxxxxxxxxxx> 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@xxxxxxxxxx>
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/