Re: [Xen-devel] [PATCH v2] x86: avoid flush IPI when possible

2016-02-18 Thread Jan Beulich
>>> On 17.02.16 at 15:48, wrote: > On 16/02/16 10:14, Jan Beulich wrote: >> --- a/xen/arch/x86/smp.c >> +++ b/xen/arch/x86/smp.c >> @@ -205,26 +205,30 @@ static unsigned int flush_flags; >> >> void invalidate_interrupt(struct cpu_user_regs *regs) >> { >> +unsigned int flags = flush_flags;

Re: [Xen-devel] [PATCH v2] x86: avoid flush IPI when possible

2016-02-17 Thread Andrew Cooper
On 16/02/16 10:14, Jan Beulich wrote: > --- a/xen/arch/x86/smp.c > +++ b/xen/arch/x86/smp.c > @@ -205,26 +205,30 @@ static unsigned int flush_flags; > > void invalidate_interrupt(struct cpu_user_regs *regs) > { > +unsigned int flags = flush_flags; > ack_APIC_irq(); > perfc_incr(ip