LoongArch: KVM: Add tracepoints for CPUCFG and CSR emulation exits

[PATCH] LoongArch: KVM: Add tracepoints for CPUCFG and CSR emulation exits

Posted by Yulong Han 3 months, 1 week ago

This patch adds tracepoints to track KVM exits caused by CPUCFG 
and CSR emulation. Note that IOCSR emulation tracing is already
covered by the generic trace_kvm_iocsr().

Signed-off-by: Yulong Han <wheatfox17@icloud.com>
---
 arch/loongarch/kvm/exit.c  |  2 ++
 arch/loongarch/kvm/trace.h | 14 +++++++++++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c
index fa52251b3bf1c..6a47a23ae9cd6 100644
--- a/arch/loongarch/kvm/exit.c
+++ b/arch/loongarch/kvm/exit.c
@@ -289,9 +289,11 @@ static int kvm_trap_handle_gspr(struct kvm_vcpu *vcpu)
 	er = EMULATE_FAIL;
 	switch (((inst.word >> 24) & 0xff)) {
 	case 0x0: /* CPUCFG GSPR */
+		trace_kvm_exit_cpucfg(vcpu, KVM_TRACE_EXIT_CPUCFG);
 		er = kvm_emu_cpucfg(vcpu, inst);
 		break;
 	case 0x4: /* CSR{RD,WR,XCHG} GSPR */
+		trace_kvm_exit_csr(vcpu, KVM_TRACE_EXIT_CSR);
 		er = kvm_handle_csr(vcpu, inst);
 		break;
 	case 0x6: /* Cache, Idle and IOCSR GSPR */
diff --git a/arch/loongarch/kvm/trace.h b/arch/loongarch/kvm/trace.h
index 1783397b1bc88..145514dab6d5b 100644
--- a/arch/loongarch/kvm/trace.h
+++ b/arch/loongarch/kvm/trace.h
@@ -46,11 +46,15 @@ DEFINE_EVENT(kvm_transition, kvm_out,
 /* Further exit reasons */
 #define KVM_TRACE_EXIT_IDLE		64
 #define KVM_TRACE_EXIT_CACHE		65
+#define KVM_TRACE_EXIT_CPUCFG		66
+#define KVM_TRACE_EXIT_CSR		67
 
 /* Tracepoints for VM exits */
 #define kvm_trace_symbol_exit_types			\
 	{ KVM_TRACE_EXIT_IDLE,		"IDLE" },	\
-	{ KVM_TRACE_EXIT_CACHE,		"CACHE" }
+	{ KVM_TRACE_EXIT_CACHE,		"CACHE" },	\
+	{ KVM_TRACE_EXIT_CPUCFG,	"CPUCFG" },	\
+	{ KVM_TRACE_EXIT_CSR,		"CSR" }
 
 DECLARE_EVENT_CLASS(kvm_exit,
 	    TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
@@ -82,6 +86,14 @@ DEFINE_EVENT(kvm_exit, kvm_exit_cache,
 	     TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
 	     TP_ARGS(vcpu, reason));
 
+DEFINE_EVENT(kvm_exit, kvm_exit_cpucfg,
+	     TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
+	     TP_ARGS(vcpu, reason));
+
+DEFINE_EVENT(kvm_exit, kvm_exit_csr,
+	     TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
+	     TP_ARGS(vcpu, reason));
+
 DEFINE_EVENT(kvm_exit, kvm_exit,
 	     TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
 	     TP_ARGS(vcpu, reason));
-- 
2.39.5

Re: [PATCH] LoongArch: KVM: Add tracepoints for CPUCFG and CSR emulation exits

Posted by Bibo Mao 3 months ago

On 2025/7/2 下午6:59, Yulong Han wrote:
> This patch adds tracepoints to track KVM exits caused by CPUCFG
> and CSR emulation. Note that IOCSR emulation tracing is already
> covered by the generic trace_kvm_iocsr().
> 
> Signed-off-by: Yulong Han <wheatfox17@icloud.com>
> ---
>   arch/loongarch/kvm/exit.c  |  2 ++
>   arch/loongarch/kvm/trace.h | 14 +++++++++++++-
>   2 files changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c
> index fa52251b3bf1c..6a47a23ae9cd6 100644
> --- a/arch/loongarch/kvm/exit.c
> +++ b/arch/loongarch/kvm/exit.c
> @@ -289,9 +289,11 @@ static int kvm_trap_handle_gspr(struct kvm_vcpu *vcpu)
>   	er = EMULATE_FAIL;
>   	switch (((inst.word >> 24) & 0xff)) {
>   	case 0x0: /* CPUCFG GSPR */
> +		trace_kvm_exit_cpucfg(vcpu, KVM_TRACE_EXIT_CPUCFG);
>   		er = kvm_emu_cpucfg(vcpu, inst);
>   		break;
>   	case 0x4: /* CSR{RD,WR,XCHG} GSPR */
> +		trace_kvm_exit_csr(vcpu, KVM_TRACE_EXIT_CSR);
>   		er = kvm_handle_csr(vcpu, inst);
>   		break;
>   	case 0x6: /* Cache, Idle and IOCSR GSPR */
> diff --git a/arch/loongarch/kvm/trace.h b/arch/loongarch/kvm/trace.h
> index 1783397b1bc88..145514dab6d5b 100644
> --- a/arch/loongarch/kvm/trace.h
> +++ b/arch/loongarch/kvm/trace.h
> @@ -46,11 +46,15 @@ DEFINE_EVENT(kvm_transition, kvm_out,
>   /* Further exit reasons */
>   #define KVM_TRACE_EXIT_IDLE		64
>   #define KVM_TRACE_EXIT_CACHE		65
> +#define KVM_TRACE_EXIT_CPUCFG		66
> +#define KVM_TRACE_EXIT_CSR		67
>   
>   /* Tracepoints for VM exits */
>   #define kvm_trace_symbol_exit_types			\
>   	{ KVM_TRACE_EXIT_IDLE,		"IDLE" },	\
> -	{ KVM_TRACE_EXIT_CACHE,		"CACHE" }
> +	{ KVM_TRACE_EXIT_CACHE,		"CACHE" },	\
> +	{ KVM_TRACE_EXIT_CPUCFG,	"CPUCFG" },	\
> +	{ KVM_TRACE_EXIT_CSR,		"CSR" }
>   
>   DECLARE_EVENT_CLASS(kvm_exit,
>   	    TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
> @@ -82,6 +86,14 @@ DEFINE_EVENT(kvm_exit, kvm_exit_cache,
>   	     TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
>   	     TP_ARGS(vcpu, reason));
>   
> +DEFINE_EVENT(kvm_exit, kvm_exit_cpucfg,
> +	     TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
> +	     TP_ARGS(vcpu, reason));
> +
> +DEFINE_EVENT(kvm_exit, kvm_exit_csr,
> +	     TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
> +	     TP_ARGS(vcpu, reason));
> +
>   DEFINE_EVENT(kvm_exit, kvm_exit,
>   	     TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
>   	     TP_ARGS(vcpu, reason));
> 
Reviewed-by: Bibo Mao <maobibo@loongson.cn>

Re: [PATCH] LoongArch: KVM: Add tracepoints for CPUCFG and CSR emulation exits

Posted by Huacai Chen 2 months, 3 weeks ago

Applied, thanks.


Huacai

On Mon, Jul 7, 2025 at 11:30 AM Bibo Mao <maobibo@loongson.cn> wrote:
>
> On 2025/7/2 下午6:59, Yulong Han wrote:
> > This patch adds tracepoints to track KVM exits caused by CPUCFG
> > and CSR emulation. Note that IOCSR emulation tracing is already
> > covered by the generic trace_kvm_iocsr().
> >
> > Signed-off-by: Yulong Han <wheatfox17@icloud.com>
> > ---
> >   arch/loongarch/kvm/exit.c  |  2 ++
> >   arch/loongarch/kvm/trace.h | 14 +++++++++++++-
> >   2 files changed, 15 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c
> > index fa52251b3bf1c..6a47a23ae9cd6 100644
> > --- a/arch/loongarch/kvm/exit.c
> > +++ b/arch/loongarch/kvm/exit.c
> > @@ -289,9 +289,11 @@ static int kvm_trap_handle_gspr(struct kvm_vcpu *vcpu)
> >       er = EMULATE_FAIL;
> >       switch (((inst.word >> 24) & 0xff)) {
> >       case 0x0: /* CPUCFG GSPR */
> > +             trace_kvm_exit_cpucfg(vcpu, KVM_TRACE_EXIT_CPUCFG);
> >               er = kvm_emu_cpucfg(vcpu, inst);
> >               break;
> >       case 0x4: /* CSR{RD,WR,XCHG} GSPR */
> > +             trace_kvm_exit_csr(vcpu, KVM_TRACE_EXIT_CSR);
> >               er = kvm_handle_csr(vcpu, inst);
> >               break;
> >       case 0x6: /* Cache, Idle and IOCSR GSPR */
> > diff --git a/arch/loongarch/kvm/trace.h b/arch/loongarch/kvm/trace.h
> > index 1783397b1bc88..145514dab6d5b 100644
> > --- a/arch/loongarch/kvm/trace.h
> > +++ b/arch/loongarch/kvm/trace.h
> > @@ -46,11 +46,15 @@ DEFINE_EVENT(kvm_transition, kvm_out,
> >   /* Further exit reasons */
> >   #define KVM_TRACE_EXIT_IDLE         64
> >   #define KVM_TRACE_EXIT_CACHE                65
> > +#define KVM_TRACE_EXIT_CPUCFG                66
> > +#define KVM_TRACE_EXIT_CSR           67
> >
> >   /* Tracepoints for VM exits */
> >   #define kvm_trace_symbol_exit_types                 \
> >       { KVM_TRACE_EXIT_IDLE,          "IDLE" },       \
> > -     { KVM_TRACE_EXIT_CACHE,         "CACHE" }
> > +     { KVM_TRACE_EXIT_CACHE,         "CACHE" },      \
> > +     { KVM_TRACE_EXIT_CPUCFG,        "CPUCFG" },     \
> > +     { KVM_TRACE_EXIT_CSR,           "CSR" }
> >
> >   DECLARE_EVENT_CLASS(kvm_exit,
> >           TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
> > @@ -82,6 +86,14 @@ DEFINE_EVENT(kvm_exit, kvm_exit_cache,
> >            TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
> >            TP_ARGS(vcpu, reason));
> >
> > +DEFINE_EVENT(kvm_exit, kvm_exit_cpucfg,
> > +          TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
> > +          TP_ARGS(vcpu, reason));
> > +
> > +DEFINE_EVENT(kvm_exit, kvm_exit_csr,
> > +          TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
> > +          TP_ARGS(vcpu, reason));
> > +
> >   DEFINE_EVENT(kvm_exit, kvm_exit,
> >            TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
> >            TP_ARGS(vcpu, reason));
> >
> Reviewed-by: Bibo Mao <maobibo@loongson.cn>
>