Re: [PATCH] x86: improve algorithm in clflush_cache_range

From: Ross Zwisler
Date: Thu Mar 12 2015 - 22:00:35 EST

On Thu, 2015-03-12 at 12:09 +0100, Ingo Molnar wrote:
> * Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> wrote:
> > The current algorithm used in clflush_cache_range() can cause the last
> > cache line of the buffer to be flushed twice.
> >
> > Fix that algorithm so that each cache line will only be flushed once,
> > and remove arithmetic on void pointers. Void pointer arithmetic is
> > allowed by GCC extensions, but isn't part of the base C standards.
> The optimization itself is fine, but that last argument is bogus: the
> Linux kernel very much relies on 'void *' arithmetics in a gazillion
> places.

Okay. Are you happy with the patch as is or would you like me to
resubmit with that bit omitted from the change log?

- Ross

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at