Re: [PATCH 0/2] generic/bitops: Always inline some more generic helpers

From: Marco Elver
Date: Thu Jan 13 2022 - 11:59:12 EST


On Thu, 13 Jan 2022 at 16:53, Borislav Petkov <bp@xxxxxxxxx> wrote:
>
> From: Borislav Petkov <bp@xxxxxxx>
>
> Hi all,
>
> a build report by the 0day robot:
>
> https://lore.kernel.org/r/Yc7t934f%2Bf/mO8lj@xxxxxxx
>
> made me look at asm and how gcc, at least, generates funky calls to the
> *_bit() bit manipulation functions on x86 instead of inlining them into
> the call sites as on x86 that's a single insn, in most of the cases.
>
> So PeterZ says the way to go is to always inline them. So here they are.
> The fun thing is that on x86 there is even a size decrease of more than
> a Kilobyte for a defconfig, which is nice, see patch 1.
>
> As always, comments and suggestions are welcome.
>
> Thx.
>
> Borislav Petkov (2):
> asm-generic/bitops: Always inline all bit manipulation helpers
> cpumask: Always inline helpers which use bit manipulation functions
>
> include/asm-generic/bitops/instrumented-atomic.h | 12 ++++++------
> .../asm-generic/bitops/instrumented-non-atomic.h | 16 ++++++++--------
> include/linux/cpumask.h | 14 +++++++-------
> 3 files changed, 21 insertions(+), 21 deletions(-)

Acked-by: Marco Elver <elver@xxxxxxxxxx>

Yup, this is probably something we should have done a long time ago. :-)

Thanks!