Messages in this thread | | | From | Andi Kleen <> | Subject | Re: [PATCH v2 8/8 only] x86,vdso: Use LSL unconditionally for vgetcpu | Date | Mon, 27 Oct 2014 04:31:02 -0700 |
| |
Andy Lutomirski <luto@amacapital.net> writes:
> LSL is faster than RDTSCP and works everywhere; there's no need to > switch between them depending on CPU.
Yes it should have been done like this from day 1.
> diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c > index 9793322751e0..d14bb8faad16 100644 > --- a/arch/x86/vdso/vclock_gettime.c > +++ b/arch/x86/vdso/vclock_gettime.c > @@ -11,6 +11,9 @@ > * Check with readelf after changing. > */ > > +/* Disable static_cpu_has debugging; it doesn't work in the vDSO */ > +#undef CONFIG_X86_DEBUG_STATIC_CPU_HAS > + > #include <uapi/linux/time.h> > #include <asm/vgtod.h> > #include <asm/hpet.h> > diff --git a/arch/x86/vdso/vgetcpu.c b/arch/x86/vdso/vgetcpu.c > index add1d98d2477..fd8470c98ab5 100644 > --- a/arch/x86/vdso/vgetcpu.c > +++ b/arch/x86/vdso/vgetcpu.c > @@ -5,10 +5,12 @@ > * Fast user context implementation of getcpu() > */ > > +/* Disable static_cpu_has debugging; it doesn't work in the vDSO */ > +#undef CONFIG_X86_DEBUG_STATIC_CPU_HAS
These two hunks are unrelated?
-Andi
-- ak@linux.intel.com -- Speaking for myself only
| |