On Thursday 16 May 2013, Michael S. Tsirkin wrote:
This improves the might_fault annotations used
by uaccess routines:
1. The only reason uaccess routines might sleep
is if they fault. Make this explicit for
all architectures.
2. Accesses (e.g through socket ops) to kernel memory
On Wed, May 22, 2013 at 11:25:36AM +0200, Arnd Bergmann wrote:
On Thursday 16 May 2013, Michael S. Tsirkin wrote:
This improves the might_fault annotations used
by uaccess routines:
1. The only reason uaccess routines might sleep
is if they fault. Make this explicit for
all
On Wed, May 22, 2013 at 11:25:36AM +0200, Arnd Bergmann wrote:
Calling might_fault() for every __get_user/__put_user is rather expensive
because it turns what should be a single instruction (plus fixup) into an
external function call.
We could hide it all behind CONFIG_DEBUG_ATOMIC_SLEEP just
On Wed, May 22, 2013 at 12:19:16PM +0200, Peter Zijlstra wrote:
On Wed, May 22, 2013 at 11:25:36AM +0200, Arnd Bergmann wrote:
Calling might_fault() for every __get_user/__put_user is rather expensive
because it turns what should be a single instruction (plus fixup) into an
external
On Wed, May 22, 2013 at 02:07:29PM +0300, Michael S. Tsirkin wrote:
On Wed, May 22, 2013 at 12:19:16PM +0200, Peter Zijlstra wrote:
On Wed, May 22, 2013 at 11:25:36AM +0200, Arnd Bergmann wrote:
Calling might_fault() for every __get_user/__put_user is rather expensive
because it turns
On Wed, May 22, 2013 at 11:25:36AM +0200, Arnd Bergmann wrote:
Given the most commonly used functions and a couple of architectures
I'm familiar with, these are the ones that currently call might_fault()
x86-32 x86-64 arm arm64 powerpc s390generic
On Wednesday 22 May 2013, Russell King - ARM Linux wrote:
On Wed, May 22, 2013 at 11:25:36AM +0200, Arnd Bergmann wrote:
Given the most commonly used functions and a couple of architectures
I'm familiar with, these are the ones that currently call might_fault()
On Wed, May 22, 2013 at 04:04:48PM +0200, Arnd Bergmann wrote:
On Wednesday 22 May 2013, Russell King - ARM Linux wrote:
On Wed, May 22, 2013 at 11:25:36AM +0200, Arnd Bergmann wrote:
Given the most commonly used functions and a couple of architectures
I'm familiar with, these are the
This improves the might_fault annotations used
by uaccess routines:
1. The only reason uaccess routines might sleep
is if they fault. Make this explicit for
all architectures.
2. Accesses (e.g through socket ops) to kernel memory
with KERNEL_DS like net/sunrpc does will never sleep.