>
>
> > PowerPC barrier instructions are needed to prevent reordering.
> >
> > Correct. The current lkpi implementation also assumes that device
> > endian == host endian. The Linux generic accessors will do use endian
> > macros to byte swap where necessary.
>
> Yes, these functions are used to ac
Correct. This is just the generic case. We just need to define the __io
macros as __compiler_membar in x86/io.h
Cheers.
-M
On Sun, Nov 18, 2018 at 13:08 Tijl Coosemans wrote:
> On Sun, 18 Nov 2018 12:10:25 -0800 Matthew Macy
> wrote:
> >> Note that these functions are normally used on uncacheab
On Sun, 18 Nov 2018 12:10:25 -0800 Matthew Macy wrote:
>> Note that these functions are normally used on uncacheable memory which
>> is strongly ordered on x86. There should be no reordering at all. On
>> PowerPC barrier instructions are needed to prevent reordering.
>
> Correct. The current
> Note that these functions are normally used on uncacheable memory which
> is strongly ordered on x86. There should be no reordering at all. On
> PowerPC barrier instructions are needed to prevent reordering.
Correct. The current lkpi implementation also assumes that device
endian == host endia
On Sat, 17 Nov 2018 14:55:05 -0800 Matthew Macy wrote:
> When looking at powerpc io.h raw and relaxed are not aliases, but it
> appears that on x86, they are:
> https://github.com/torvalds/linux/blob/master/arch/x86/include/asm/io.h
>
> Sorry for the noise. But let's starting moving the x86 speci
When looking at powerpc io.h raw and relaxed are not aliases, but it
appears that on x86, they are:
https://github.com/torvalds/linux/blob/master/arch/x86/include/asm/io.h
Sorry for the noise. But let's starting moving the x86 specific
atomic.h and io.h under asm/x86.
Thanks.
On Sat, Nov 17, 2
You should probably revert this. The implied understanding of the _relaxed
version is incorrect. compiler_membar is there to prevent instruction
reordering which is possible on FreeBSD because the accesses are done in C.
The relaxed variants still do not permit instruction reordering. On Linux
__co
