Re: [PATCH RFC 2/2] x86/vdso: Add VCLOCK_HVCLOCK vDSO clock read method

2017-02-08 Thread Thomas Gleixner
On Wed, 8 Feb 2017, Andy Lutomirski wrote: > > +#ifdef CONFIG_HYPERV_CLOCK > > +/* (a * b) >> 64 implementation */ > > +static inline u64 mul64x64_hi(u64 a, u64 b) > > +{ > > + u64 a_lo, a_hi, b_lo, b_hi, p1, p2; > > + > > + a_lo = (u32)a; > > + a_hi = a >> 32; > > + b_lo =

Re: [PATCH RFC 2/2] x86/vdso: Add VCLOCK_HVCLOCK vDSO clock read method

2017-02-08 Thread Vitaly Kuznetsov
Andy Lutomirski writes: > On Wed, Feb 8, 2017 at 9:07 AM, Vitaly Kuznetsov wrote: >> Hyper-V TSC page clocksource is suitable for vDSO, however, the protocol >> defined by the hypervisor is different from VCLOCK_PVCLOCK. Implement the >> required

Re: [PATCH RFC 2/2] x86/vdso: Add VCLOCK_HVCLOCK vDSO clock read method

2017-02-08 Thread Andy Lutomirski
On Wed, Feb 8, 2017 at 9:07 AM, Vitaly Kuznetsov wrote: > Hyper-V TSC page clocksource is suitable for vDSO, however, the protocol > defined by the hypervisor is different from VCLOCK_PVCLOCK. Implement the > required support re-using pvclock_page VVAR as VCLOCK_PVCLOCK is

[PATCH RFC 2/2] x86/vdso: Add VCLOCK_HVCLOCK vDSO clock read method

2017-02-08 Thread Vitaly Kuznetsov
Hyper-V TSC page clocksource is suitable for vDSO, however, the protocol defined by the hypervisor is different from VCLOCK_PVCLOCK. Implement the required support re-using pvclock_page VVAR as VCLOCK_PVCLOCK is mutually exclusive with VCLOCK_HVCLOCK at run time. Signed-off-by: Vitaly Kuznetsov