diff mbox series

[1/2] RISCV: KVM: add tracepoints for entry and exit events

Message ID 20240328031220.1287-2-liangshenlin@eswincomputing.com (mailing list archive)
State New, archived
Headers show
Series perf kvm: Add kvm stat support on riscv | expand

Commit Message

Shenlin Liang March 28, 2024, 3:12 a.m. UTC 
Like other architectures, RISCV KVM also needs to add these event
tracepoints to count the number of times kvm guest entry/exit.

Signed-off-by: Shenlin Liang <liangshenlin@eswincomputing.com>
---
 arch/riscv/kvm/trace_riscv.h | 60 ++++++++++++++++++++++++++++++++++++
 arch/riscv/kvm/vcpu.c        |  7 +++++
 2 files changed, 67 insertions(+)
 create mode 100644 arch/riscv/kvm/trace_riscv.h

Comments

Anup Patel April 8, 2024, 12:07 p.m. UTC | #1 
On Thu, Mar 28, 2024 at 8:49 AM Shenlin Liang
<liangshenlin@eswincomputing.com> wrote:
>
> Like other architectures, RISCV KVM also needs to add these event
> tracepoints to count the number of times kvm guest entry/exit.
>
> Signed-off-by: Shenlin Liang <liangshenlin@eswincomputing.com>
> ---
>  arch/riscv/kvm/trace_riscv.h | 60 ++++++++++++++++++++++++++++++++++++
>  arch/riscv/kvm/vcpu.c        |  7 +++++
>  2 files changed, 67 insertions(+)
>  create mode 100644 arch/riscv/kvm/trace_riscv.h
>
> diff --git a/arch/riscv/kvm/trace_riscv.h b/arch/riscv/kvm/trace_riscv.h
> new file mode 100644
> index 000000000000..5848083c7a5e
> --- /dev/null
> +++ b/arch/riscv/kvm/trace_riscv.h
> @@ -0,0 +1,60 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Tracepoints for RISC-V KVM
> + *
> + * Copyright 2024 Beijing ESWIN Computing Technology Co., Ltd.
> + *
> + */
> +#if !defined(_TRACE_RSICV_KVM_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _TRACE_RSICV_KVM_H

s/_RSICV_/_RISCV_/

> +
> +#include <linux/tracepoint.h>
> +
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM kvm
> +
> +TRACE_EVENT(kvm_entry,
> +       TP_PROTO(struct kvm_vcpu *vcpu),
> +       TP_ARGS(vcpu),
> +
> +       TP_STRUCT__entry(
> +               __field(unsigned long, pc)
> +       ),
> +
> +       TP_fast_assign(
> +               __entry->pc     = vcpu->arch.guest_context.sepc;
> +       ),
> +
> +       TP_printk("PC: 0x%016lx", __entry->pc)
> +);
> +
> +TRACE_EVENT(kvm_exit,
> +       TP_PROTO(struct kvm_vcpu *vcpu, unsigned long exit_reason,
> +                       unsigned long scause),
> +       TP_ARGS(vcpu, exit_reason, scause),
> +
> +       TP_STRUCT__entry(
> +               __field(unsigned long, pc)
> +               __field(unsigned long, exit_reason)
> +               __field(unsigned long, scause)

This is not the right contents describing a KVM exit.

The fields over here should be aligned with "struct kvm_cpu_trap"
so we should have following fields:
    __field(unsigned long, sepc)
    __field(unsigned long, scause)
    __field(unsigned long, stval)
    __field(unsigned long, htval)
    __field(unsigned long, htinst)

> +       ),
> +
> +       TP_fast_assign(
> +               __entry->pc             = vcpu->arch.guest_context.sepc;
> +               __entry->exit_reason    = exit_reason;
> +               __entry->scause         = scause;
> +       ),
> +
> +       TP_printk("EXIT_REASON:0x%lx,PC: 0x%016lx,SCAUSE:0x%lx",
> +                       __entry->exit_reason, __entry->pc, __entry->scause)
> +);
> +
> +#endif /* _TRACE_RSICV_KVM_H */
> +
> +#undef TRACE_INCLUDE_PATH
> +#define TRACE_INCLUDE_PATH .
> +#undef TRACE_INCLUDE_FILE
> +#define TRACE_INCLUDE_FILE trace_riscv
> +
> +/* This part must be outside protection */
> +#include <trace/define_trace.h>
> diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
> index b5ca9f2e98ac..ed0932f0d514 100644
> --- a/arch/riscv/kvm/vcpu.c
> +++ b/arch/riscv/kvm/vcpu.c
> @@ -21,6 +21,9 @@
>  #include <asm/cacheflush.h>
>  #include <asm/kvm_vcpu_vector.h>
>
> +#define CREATE_TRACE_POINTS
> +#include "trace_riscv.h"
> +
>  const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
>         KVM_GENERIC_VCPU_STATS(),
>         STATS_DESC_COUNTER(VCPU, ecall_exit_stat),
> @@ -782,6 +785,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
>                  */
>                 kvm_riscv_local_tlb_sanitize(vcpu);
>
> +               trace_kvm_entry(vcpu);
> +
>                 guest_timing_enter_irqoff();
>
>                 kvm_riscv_vcpu_enter_exit(vcpu);
> @@ -820,6 +825,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
>
>                 local_irq_enable();
>
> +               trace_kvm_exit(vcpu, run->exit_reason, trap.scause);
> +
>                 preempt_enable();
>
>                 kvm_vcpu_srcu_read_lock(vcpu);
> --
> 2.37.2
>

Regards,
Anup
Eric Cheng April 10, 2024, 7:12 a.m. UTC | #2 
On 3/28/2024 11:12 AM, Shenlin Liang wrote:
> Like other architectures, RISCV KVM also needs to add these event
> tracepoints to count the number of times kvm guest entry/exit.
> 
> Signed-off-by: Shenlin Liang <liangshenlin@eswincomputing.com>
> ---
>   arch/riscv/kvm/trace_riscv.h | 60 ++++++++++++++++++++++++++++++++++++

Conventionally, it should be named to trace.h, especially if only one. Refer to 
other arch's.
Shenlin Liang April 11, 2024, 7:24 a.m. UTC | #3 
On 2024-04-08 20:37, Anup Patel <anup@brainfault.org> wrote:

> 
> On Thu, Mar 28, 2024 at 8:49 AM Shenlin Liang
> <liangshenlin@eswincomputing.com> wrote:
> >
> > Like other architectures, RISCV KVM also needs to add these event
> > tracepoints to count the number of times kvm guest entry/exit.
> >
> > Signed-off-by: Shenlin Liang <liangshenlin@eswincomputing.com>
> > ---
> >  arch/riscv/kvm/trace_riscv.h | 60 ++++++++++++++++++++++++++++++++++++
> >  arch/riscv/kvm/vcpu.c        |  7 +++++
> >  2 files changed, 67 insertions(+)
> >  create mode 100644 arch/riscv/kvm/trace_riscv.h
> >
> > diff --git a/arch/riscv/kvm/trace_riscv.h b/arch/riscv/kvm/trace_riscv.h
> > new file mode 100644
> > index 000000000000..5848083c7a5e
> > --- /dev/null
> > +++ b/arch/riscv/kvm/trace_riscv.h
> > @@ -0,0 +1,60 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Tracepoints for RISC-V KVM
> > + *
> > + * Copyright 2024 Beijing ESWIN Computing Technology Co., Ltd.
> > + *
> > + */
> > +#if !defined(_TRACE_RSICV_KVM_H) || defined(TRACE_HEADER_MULTI_READ)
> > +#define _TRACE_RSICV_KVM_H
> 
> s/_RSICV_/_RISCV_/
> 
> > +
> > +#include <linux/tracepoint.h>
> > +
> > +#undef TRACE_SYSTEM
> > +#define TRACE_SYSTEM kvm
> > +
> > +TRACE_EVENT(kvm_entry,
> > +       TP_PROTO(struct kvm_vcpu *vcpu),
> > +       TP_ARGS(vcpu),
> > +
> > +       TP_STRUCT__entry(
> > +               __field(unsigned long, pc)
> > +       ),
> > +
> > +       TP_fast_assign(
> > +               __entry->pc     = vcpu->arch.guest_context.sepc;
> > +       ),
> > +
> > +       TP_printk("PC: 0x%016lx", __entry->pc)
> > +);
> > +
> > +TRACE_EVENT(kvm_exit,
> > +       TP_PROTO(struct kvm_vcpu *vcpu, unsigned long exit_reason,
> > +                       unsigned long scause),
> > +       TP_ARGS(vcpu, exit_reason, scause),
> > +
> > +       TP_STRUCT__entry(
> > +               __field(unsigned long, pc)
> > +               __field(unsigned long, exit_reason)
> > +               __field(unsigned long, scause)
> 
> This is not the right contents describing a KVM exit.
> 
> The fields over here should be aligned with "struct kvm_cpu_trap"
> so we should have following fields:
>     __field(unsigned long, sepc)
>     __field(unsigned long, scause)
>     __field(unsigned long, stval)
>     __field(unsigned long, htval)
>     __field(unsigned long, htinst)
> 
> > +       ),
> > +
> > +       TP_fast_assign(
> > +               __entry->pc             = vcpu->arch.guest_context.sepc;
> > +               __entry->exit_reason    = exit_reason;
> > +               __entry->scause         = scause;
> > +       ),
> > +
> > +       TP_printk("EXIT_REASON:0x%lx,PC: 0x%016lx,SCAUSE:0x%lx",
> > +                       __entry->exit_reason, __entry->pc, __entry->scause)
> > +);
> > +
> > +#endif /* _TRACE_RSICV_KVM_H */
> > +
> > +#undef TRACE_INCLUDE_PATH
> > +#define TRACE_INCLUDE_PATH .
> > +#undef TRACE_INCLUDE_FILE
> > +#define TRACE_INCLUDE_FILE trace_riscv
> > +
> > +/* This part must be outside protection */
> > +#include <trace/define_trace.h>
> > diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
> > index b5ca9f2e98ac..ed0932f0d514 100644
> > --- a/arch/riscv/kvm/vcpu.c
> > +++ b/arch/riscv/kvm/vcpu.c
> > @@ -21,6 +21,9 @@
> >  #include <asm/cacheflush.h>
> >  #include <asm/kvm_vcpu_vector.h>
> >
> > +#define CREATE_TRACE_POINTS
> > +#include "trace_riscv.h"
> > +
> >  const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
> >         KVM_GENERIC_VCPU_STATS(),
> >         STATS_DESC_COUNTER(VCPU, ecall_exit_stat),
> > @@ -782,6 +785,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
> >                  */
> >                 kvm_riscv_local_tlb_sanitize(vcpu);
> >
> > +               trace_kvm_entry(vcpu);
> > +
> >                 guest_timing_enter_irqoff();
> >
> >                 kvm_riscv_vcpu_enter_exit(vcpu);
> > @@ -820,6 +825,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
> >
> >                 local_irq_enable();
> >
> > +               trace_kvm_exit(vcpu, run->exit_reason, trap.scause);
> > +
> >                 preempt_enable();
> >
> >                 kvm_vcpu_srcu_read_lock(vcpu);
> > --
> > 2.37.2
> >
> 
> Regards,
> Anup

Thank you for the review. I will send the v2 version.
Shenlin Liang April 11, 2024, 7:24 a.m. UTC | #4 
On 2024-04-10 15:12, Eric Cheng <eric.cheng.linux@gmail.com> wrote:

> 
> On 3/28/2024 11:12 AM, Shenlin Liang wrote:
> > Like other architectures, RISCV KVM also needs to add these event
> > tracepoints to count the number of times kvm guest entry/exit.
> > 
> > Signed-off-by: Shenlin Liang <liangshenlin@eswincomputing.com>
> > ---
> >   arch/riscv/kvm/trace_riscv.h | 60 ++++++++++++++++++++++++++++++++++++
> 
> Conventionally, it should be named to trace.h, especially if only one. Refer to 
> other arch's.

Thank you for the review. I will send the v2 version.
diff mbox series

Patch

diff --git a/arch/riscv/kvm/trace_riscv.h b/arch/riscv/kvm/trace_riscv.h
new file mode 100644
index 000000000000..5848083c7a5e
--- /dev/null
+++ b/arch/riscv/kvm/trace_riscv.h
@@ -0,0 +1,60 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Tracepoints for RISC-V KVM
+ *
+ * Copyright 2024 Beijing ESWIN Computing Technology Co., Ltd.
+ *
+ */
+#if !defined(_TRACE_RSICV_KVM_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_RSICV_KVM_H
+
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM kvm
+
+TRACE_EVENT(kvm_entry,
+	TP_PROTO(struct kvm_vcpu *vcpu),
+	TP_ARGS(vcpu),
+
+	TP_STRUCT__entry(
+		__field(unsigned long, pc)
+	),
+
+	TP_fast_assign(
+		__entry->pc	= vcpu->arch.guest_context.sepc;
+	),
+
+	TP_printk("PC: 0x%016lx", __entry->pc)
+);
+
+TRACE_EVENT(kvm_exit,
+	TP_PROTO(struct kvm_vcpu *vcpu, unsigned long exit_reason,
+			unsigned long scause),
+	TP_ARGS(vcpu, exit_reason, scause),
+
+	TP_STRUCT__entry(
+		__field(unsigned long, pc)
+		__field(unsigned long, exit_reason)
+		__field(unsigned long, scause)
+	),
+
+	TP_fast_assign(
+		__entry->pc		= vcpu->arch.guest_context.sepc;
+		__entry->exit_reason	= exit_reason;
+		__entry->scause		= scause;
+	),
+
+	TP_printk("EXIT_REASON:0x%lx,PC: 0x%016lx,SCAUSE:0x%lx",
+			__entry->exit_reason, __entry->pc, __entry->scause)
+);
+
+#endif /* _TRACE_RSICV_KVM_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE trace_riscv
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
index b5ca9f2e98ac..ed0932f0d514 100644
--- a/arch/riscv/kvm/vcpu.c
+++ b/arch/riscv/kvm/vcpu.c
@@ -21,6 +21,9 @@ 
 #include <asm/cacheflush.h>
 #include <asm/kvm_vcpu_vector.h>
 
+#define CREATE_TRACE_POINTS
+#include "trace_riscv.h"
+
 const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
 	KVM_GENERIC_VCPU_STATS(),
 	STATS_DESC_COUNTER(VCPU, ecall_exit_stat),
@@ -782,6 +785,8 @@  int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 		 */
 		kvm_riscv_local_tlb_sanitize(vcpu);
 
+		trace_kvm_entry(vcpu);
+
 		guest_timing_enter_irqoff();
 
 		kvm_riscv_vcpu_enter_exit(vcpu);
@@ -820,6 +825,8 @@  int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 
 		local_irq_enable();
 
+		trace_kvm_exit(vcpu, run->exit_reason, trap.scause);
+
 		preempt_enable();
 
 		kvm_vcpu_srcu_read_lock(vcpu);