Re: [PATCH v2 0/3] io.h, logic_pio: Allow barriers for inX() and outX() be overridden

Wei Xu
2020-05-15T07:07:30Z

Hi John,

On 2020/3/28 0:06, John Garry wrote:
> Since commits a7851aa54c0c ("io: change outX() to have their own IO
> barrier overrides") and 87fe2d543f81 ("io: change inX() to have their own
> IO barrier overrides"), the outX() and inX() functions have memory
> barriers which can be overridden per-arch.
>
> However, under CONFIG_INDIRECT_PIO, logic_pio defines its own version of
> inX() and outX(), which still use readb et al. For these, the barrier
> after a raw read is weaker than it otherwise would be.
>
> This series generates consistent behaviour for logic_pio, by defining
> generic _inX() and _outX() in asm-generic/io.h, and using those in
> logic_pio. Generic _inX() and _outX() have per-arch overrideable
> barriers.
>
> The topic was discussed there originally:
> https://lore.kernel.org/lkml/2e80d7bc-32a0-cc40-00a9-8a383a1966c2@huawei.com/
>
> A small tidy-up patch is included.
>
> I hope that series can go through the arm-soc tree, as with other recent
> logic_pio changes.
>
> Hi Arnd,
>
> I added your tag, but please let me know if you have any issue with the
> updated change in patch #1.
>
> cheers
>
> - Differences to v1
> - fix x86 clang build by adding extra build swicth for _{in,out}X
> - added Arnd's RB tag
>
> John Garry (3):
> io: Provide _inX() and _outX()
> logic_pio: Improve macro argument name
> logic_pio: Use _inX() and _outX()
>
> include/asm-generic/io.h | 64 +++++++++++++++++++++++++++++++++---------------
> lib/logic_pio.c | 22 ++++++++---------
> 2 files changed, 55 insertions(+), 31 deletions(-)
>

Thanks!
Series applied to the hisilicon SoC tree.

Best Regards,
Wei