Re: [PATCH v2] xen/lib: introduce generic find next bit operations

[Oleksii <oleksii.kurochko@xxxxxxxxx>]

Hi Julien,

On Tue, 2024-02-13 at 17:18 +0000, Julien Grall wrote:
> Hi Oleksii,
> 
> On 09/02/2024 17:58, Oleksii Kurochko wrote:
> > find-next-bit.c is common for Arm64, PPC and RISCV64,
> > so it is moved to xen/lib.
> > 
> > PPC has been transitioned to generic functions from find-next-bit.c
> > since it now shares the same implementation as the PPC-specific
> > code.
> > 
> > The MISRA exclude list has been updated to verify
> > lib/find-next-bit.c instead of Arm's find_next_bit.c,
> > as Arm's find_next_bit.c has been relocated to xen/lib/.
> > 
> > Despite CONFIG_GENERIC_FIND_FIRST_BIT not currently being used in
> > Xen and being removed from the Linux kernel [1], it could
> > theoretically
> > prove useful for Xen. This is because the Linux kernel transitioned
> > Arm to the generic version of find_first_bit() and
> > find_first_zero_bit() due to improvements [1] in both performance
> > and .text size.
> > It would be prudent to investigate whether [1] is applicable to Xen
> > as well and, if so, implement the necessary changes in a separate
> > patch.
> > 
> > [1]
> > https://lore.kernel.org/linux-arch/20211005054059.475634-5-yury.norov@xxxxxxxxx/
> > 
> > Suggested-by: Jan Beulich <jbeulich@xxxxxxxx>
> > Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
> 
> Reviewed-by: Julien Grall <jgrall@xxxxxxxxxx>
Thanks for review.

~ Oleksii