Re: [PATCH 7/7] tracing/hyper-v: trace hyperv_mmu_flush_tlb_others()

From: Steven Rostedt
Date: Fri Apr 07 2017 - 10:38:22 EST


On Fri, 7 Apr 2017 13:27:01 +0200
Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> wrote:

> Add Hyper-V tracing subsystem and trace hyperv_mmu_flush_tlb_others().
> Tracing is done the same way we do xen_mmu_flush_tlb_others().
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> ---
> MAINTAINERS | 1 +
> arch/x86/hyperv/mmu.c | 6 ++++++
> include/trace/events/hyperv.h | 30 ++++++++++++++++++++++++++++++
> 3 files changed, 37 insertions(+)
> create mode 100644 include/trace/events/hyperv.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 819d5e8..9785d98 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -6057,6 +6057,7 @@ F: drivers/scsi/storvsc_drv.c
> F: drivers/uio/uio_hv_generic.c
> F: drivers/video/fbdev/hyperv_fb.c
> F: include/linux/hyperv.h
> +F: include/trace/events/hyperv.h
> F: tools/hv/
> F: Documentation/ABI/stable/sysfs-bus-vmbus
>
> diff --git a/arch/x86/hyperv/mmu.c b/arch/x86/hyperv/mmu.c
> index fb487cb..61f2a5b 100644
> --- a/arch/x86/hyperv/mmu.c
> +++ b/arch/x86/hyperv/mmu.c
> @@ -5,6 +5,10 @@
> #include <asm/tlbflush.h>
> #include <asm/msr.h>
> #include <asm/fpu/api.h>
> +#include <trace/events/hyperv.h>
> +
> +#define CREATE_TRACE_POINTS
> +DEFINE_TRACE(hyperv_mmu_flush_tlb_others);
>
> /*
> * Arbitrary number; we need to pre-allocate per-cpu struct for doing TLB
> @@ -36,6 +40,8 @@ static void hyperv_flush_tlb_others(const struct cpumask *cpus,
> u64 status = -1ULL;
> int cpu, vcpu, gva_n;
>
> + trace_hyperv_mmu_flush_tlb_others(cpus, mm, start, end);
> +
> if (!pcpu_flush || !hv_hypercall_pg)
> goto do_native;
>
> diff --git a/include/trace/events/hyperv.h b/include/trace/events/hyperv.h
> new file mode 100644
> index 0000000..e37e72d
> --- /dev/null
> +++ b/include/trace/events/hyperv.h

Since this is architecture specific code, can you keep the header file
in arch/x86?

You can see how to do this in the samples/trace_events/ directory and
see other examples in x86 like arch/x86/kvm/trace.h and
arch/x86/include/asm/trace/mpx.h.

Thanks,

-- Steve

> @@ -0,0 +1,30 @@
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM hyperv
> +
> +#if !defined(_TRACE_HYPERV_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _TRACE_HYPERV_H
> +
> +#include <linux/tracepoint.h>
> +
> +TRACE_EVENT(hyperv_mmu_flush_tlb_others,
> + TP_PROTO(const struct cpumask *cpus, struct mm_struct *mm,
> + unsigned long addr, unsigned long end),
> + TP_ARGS(cpus, mm, addr, end),
> + TP_STRUCT__entry(
> + __field(unsigned int, ncpus)
> + __field(struct mm_struct *, mm)
> + __field(unsigned long, addr)
> + __field(unsigned long, end)
> + ),
> + TP_fast_assign(__entry->ncpus = cpumask_weight(cpus);
> + __entry->mm = mm;
> + __entry->addr = addr,
> + __entry->end = end),
> + TP_printk("ncpus %d mm %p addr %lx, end %lx",
> + __entry->ncpus, __entry->mm, __entry->addr, __entry->end)
> + );
> +
> +#endif /* _TRACE_HYPERV_H */
> +
> +/* This part must be outside protection */
> +#include <trace/define_trace.h>