Re: autoconf stalls while checking "atomic builtins for 64 bit data types"

[John David Anglin <dave.anglin@bell.net>]

On 2017-10-19 2:05 AM, Helge Deller wrote:
> > + checking whether the compiler provides atomic builtins for 64 bit 
> > data types... yes
>
> Although the 32-bit parisc kernel now provides 64-bit atomics, I'd 
> suggest
> to stay on "native word width" when writing locking functions.
> That means, on a 32-bit kernel ideally 32-bit atomics should be used.
> We believe that our 64-bit atomic functions do work, but
> there might be cornercases where it doesn't work 100% reliable.
Yes, there is a semaphore and interrupts are disabled, but the loads are 
not atomic from
a memory standpoint.  So, I agree with Helge's comment.

Dave

--
John David Anglin  dave.anglin@bell.net