On Sat, Jul 04, 2015 at 10:26:53AM +0200, Ingo Molnar wrote: > > * Vitaly Kuznetsov <[email protected]> wrote: > > > Hypervisor callback interrupts are only accounted on Xen/Hyper-V and we > > detect hypervisor's type in early boot. There is no point in having > > always-zero HYP: line on other hypervisors or bare metal. > > > > Suggested-by: Radim Krčmář <[email protected]> > > Signed-off-by: Vitaly Kuznetsov <[email protected]> > > --- > > arch/x86/kernel/irq.c | 13 +++++++++---- > > 1 file changed, 9 insertions(+), 4 deletions(-) > > > > diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c > > index 88b36648..0c82064 100644 > > --- a/arch/x86/kernel/irq.c > > +++ b/arch/x86/kernel/irq.c > > @@ -18,6 +18,7 @@ > > #include <asm/mce.h> > > #include <asm/hw_irq.h> > > #include <asm/desc.h> > > +#include <asm/hypervisor.h> > > > > #define CREATE_TRACE_POINTS > > #include <asm/trace/irq_vectors.h> > > @@ -139,10 +140,14 @@ int arch_show_interrupts(struct seq_file *p, int prec) > > seq_puts(p, " Machine check polls\n"); > > #endif > > #if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN) > > - seq_printf(p, "%*s: ", prec, "HYP"); > > - for_each_online_cpu(j) > > - seq_printf(p, "%10u ", irq_stats(j)->irq_hv_callback_count); > > - seq_puts(p, " Hypervisor callback interrupts\n"); > > + if (x86_hyper == &x86_hyper_ms_hyperv || > > + x86_hyper == &x86_hyper_xen) { > > + seq_printf(p, "%*s: ", prec, "HYP"); > > + for_each_online_cpu(j) > > + seq_printf(p, "%10u ", > > + irq_stats(j)->irq_hv_callback_count); > > + seq_puts(p, " Hypervisor callback interrupts\n"); > > + } > > So I think we should simplify this to: > > if (x86_hyper) { > ... > } > > this will print the HYP line on hypervisors that don't use > HYPERVISOR_CALLBACK_VECTOR, but it will make it a lot more self-maintaining, > we > won't accidentally skip this line on hypervisors that start using the > callback > IRQ.
This is a good point. When virt stuff creeps out, it's easy to lose track of it. But, I would prefer that vmware and kvm guests don't have to have a meaningless counter in /proc/interrupts. Also, for xen, I see that it only matters for x86. ARM xen builds would also have a meaningless counter. Maybe we should add a flags member to hypervisor_x86, and start using that in these types of situations. Thanks, drew -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
