Implement atomic_swap_xxx() for all platforms

[• hselasky]

Currently running a universe build.

[kib]

sys/mips/include/atomic.h

794

Do we provide ack/rel variants of swap on any other arch ?
Also, if you use fcmpset_acq/rel, I do not see why do you need additional thread fences.

sys/powerpc/include/atomic.h

856

I suspect this might not compile.

[• hselasky]

Compile fix.

[• hselasky]

sys/powerpc/include/atomic.h

856

Other places I see the same #define . I'm currently doing a universe, so I will know.

[• hselasky]

sys/mips/include/atomic.h

794

No, usually not. Do you want me to clear those variants?

[kib]

sys/mips/include/atomic.h

794

Yes, I think it is better not to do that, both due to the precedent and because the implementation is somewhat questionable.

sys/powerpc/include/atomic.h

856

It would work if the real implementation function does explicit cast to uint32_t or uint32_t is typedef for long. If it is typedef to int, then this should break.

[• hselasky]

Update as per suggestion from @kib

[kib]

sys/arm/include/atomic-v6.h

776

I think you can put this function into arm/include/atomic.h and avoid writing it twice.

sys/mips/include/atomic.h

761

Style does not allow to initialize at declaration.

[• hselasky]

Compile fixes.

[kib]

Asm versions of the mips swap() primitives would be less ugly, but I think this can be taken care of by the mips people.

[• hselasky]

More minor build fixes. u_int is not always defined when including atomic.h. Use uint32_t instead.

[kib]

sys/powerpc/include/atomic.h

856

But you still use u_int there ?

[• hselasky]

Yes, but those are macros, so they are not compiled when the header file is included.

I'm seeing something like this:

so9899:1999 -Werror  /usr/img/freebsd/sys/dev/cfe/cfe_api.c
In file included from /usr/img/freebsd/sys/sys/systm.h:44,
                 from /usr/img/freebsd/sys/dev/cfe/cfe_api.h:67,
                 from /usr/img/freebsd/sys/dev/cfe/cfe_api.c:54:
./machine/atomic.h: In function 'atomic_swap_long':
./machine/atomic.h:803: error: expected ')' before 'u_int'
cc1: warnings being treated as errors
./machine/atomic.h:803: warning: type defaults to 'int' in declaration of 'type name'
./machine/atomic.h:803: error: 'u_int' undeclared (first use in this function)
./machine/atomic.h:803: error: (Each undeclared identifier is reported only once
./machine/atomic.h:803: error: for each function it appears in.)
./machine/atomic.h:803: error: expected expression before ')' token
./machine/atomic.h:803: warning: passing argument 1 of 'atomic_fcmpset_32' makes pointer from integer without a cast
./machine/atomic.h: In function 'atomic_swap_ptr':
./machine/atomic.h:815: error: expected ')' before 'u_int'
./machine/atomic.h:815: warning: type defaults to 'int' in declaration of 'type name'
./machine/atomic.h:815: error: 'u_int' undeclared (first use in this function)
./machine/atomic.h:815: error: expected expression before ')' token
./machine/atomic.h:815: warning: passing argument 1 of 'atomic_fcmpset_32' makes pointer from integer without a cast
--- bcm_machdep.o ---

[arichardson]

head/sys/mips/include/atomic.h

803 ↗

(On Diff #51810)

This seems wrong: long is 64 bytes on MIPS64.

[• hselasky]

head/sys/mips/include/atomic.h

803 ↗

(On Diff #51810)

I'll fix.

[imp]

head/sys/mips/include/atomic.h

782 ↗

(On Diff #51810)

This still isn't defined on 32-bit mips then, is it?

[• hselasky]

head/sys/mips/include/atomic.h

782 ↗

(On Diff #51810)

I guess someone with MIPS platform knowledge will need to fix this.

[imp]

head/sys/mips/include/atomic.h

782 ↗

(On Diff #51810)

I can fix it...