Re: [RFC 3/4] Restartable sequences: Wire up powerpc system call

[Mathieu Desnoyers]

----- On Jul 27, 2016, at 11:05 AM, Boqun Feng boqun.feng@xxxxxxxxx wrote:

> Wire up the rseq system call on powerpc.
> 
> This provides an ABI improving the speed of a user-space getcpu
> operation on powerpc by skipping the getcpu system call on the fast
> path, as well as improving the speed of user-space operations on per-cpu
> data compared to using load-reservation/store-conditional atomics.

Picked up in my dev branch too, thanks!

Mathieu

> 
> Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
> ---
> arch/powerpc/include/asm/systbl.h      | 1 +
> arch/powerpc/include/asm/unistd.h      | 2 +-
> arch/powerpc/include/uapi/asm/unistd.h | 1 +
> 3 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/include/asm/systbl.h
> b/arch/powerpc/include/asm/systbl.h
> index 2fc5d4db503c..c68f4d0d00b2 100644
> --- a/arch/powerpc/include/asm/systbl.h
> +++ b/arch/powerpc/include/asm/systbl.h
> @@ -386,3 +386,4 @@ SYSCALL(mlock2)
> SYSCALL(copy_file_range)
> COMPAT_SYS_SPU(preadv2)
> COMPAT_SYS_SPU(pwritev2)
> +SYSCALL(rseq)
> diff --git a/arch/powerpc/include/asm/unistd.h
> b/arch/powerpc/include/asm/unistd.h
> index cf12c580f6b2..a01e97d3f305 100644
> --- a/arch/powerpc/include/asm/unistd.h
> +++ b/arch/powerpc/include/asm/unistd.h
> @@ -12,7 +12,7 @@
> #include <uapi/asm/unistd.h>
> 
> 
> -#define NR_syscalls		382
> +#define NR_syscalls		383
> 
> #define __NR__exit __NR_exit
> 
> diff --git a/arch/powerpc/include/uapi/asm/unistd.h
> b/arch/powerpc/include/uapi/asm/unistd.h
> index e9f5f41aa55a..d1849d64c8ef 100644
> --- a/arch/powerpc/include/uapi/asm/unistd.h
> +++ b/arch/powerpc/include/uapi/asm/unistd.h
> @@ -392,5 +392,6 @@
> #define __NR_copy_file_range	379
> #define __NR_preadv2		380
> #define __NR_pwritev2		381
> +#define __NR_rseq		382
> 
> #endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */
> --
> 2.9.0

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com