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Signed-off-by: Vincent Donnefort diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_= asm.h index 352ebbedaab2..c5cb2adde7ed 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -94,6 +94,7 @@ enum __kvm_host_smccc_func { __KVM_HOST_SMCCC_FUNC___tracing_enable, __KVM_HOST_SMCCC_FUNC___tracing_swap_reader, __KVM_HOST_SMCCC_FUNC___tracing_update_clock, + __KVM_HOST_SMCCC_FUNC___tracing_reset, }; =20 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] diff --git a/arch/arm64/kvm/hyp/include/nvhe/trace.h b/arch/arm64/kvm/hyp/i= nclude/nvhe/trace.h index fd641e1b1c23..44912869d184 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/trace.h +++ b/arch/arm64/kvm/hyp/include/nvhe/trace.h @@ -12,6 +12,7 @@ void __tracing_unload(void); int __tracing_enable(bool enable); int __tracing_swap_reader(unsigned int cpu); void __tracing_update_clock(u32 mult, u32 shift, u64 epoch_ns, u64 epoch_c= yc); +int __tracing_reset(unsigned int cpu); #else static inline void *tracing_reserve_entry(unsigned long length) { return N= ULL; } static inline void tracing_commit_entry(void) { } @@ -21,5 +22,6 @@ static inline void __tracing_unload(void) { } static inline int __tracing_enable(bool enable) { return -ENODEV; } static inline int __tracing_swap_reader(unsigned int cpu) { return -ENODEV= ; } static inline void __tracing_update_clock(u32 mult, u32 shift, u64 epoch_n= s, u64 epoch_cyc) { } +static inline int __tracing_reset(unsigned int cpu) { return -ENODEV; } #endif #endif diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/h= yp-main.c index 9df0d37a494b..5acbd451efbd 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -625,6 +625,13 @@ static void handle___tracing_update_clock(struct kvm_c= pu_context *host_ctxt) __tracing_update_clock(mult, shift, epoch_ns, epoch_cyc); } =20 +static void handle___tracing_reset(struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(unsigned int, cpu, host_ctxt, 1); + + cpu_reg(host_ctxt, 1) =3D __tracing_reset(cpu); +} + typedef void (*hcall_t)(struct kvm_cpu_context *); =20 #define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] =3D (hcall_t)handle_##x @@ -671,6 +678,7 @@ static const hcall_t host_hcall[] =3D { HANDLE_FUNC(__tracing_enable), HANDLE_FUNC(__tracing_swap_reader), HANDLE_FUNC(__tracing_update_clock), + HANDLE_FUNC(__tracing_reset), }; =20 static void handle_host_hcall(struct kvm_cpu_context *host_ctxt) diff --git a/arch/arm64/kvm/hyp/nvhe/trace.c b/arch/arm64/kvm/hyp/nvhe/trac= e.c index 97e9f6c1a52c..93475cc36640 100644 --- a/arch/arm64/kvm/hyp/nvhe/trace.c +++ b/arch/arm64/kvm/hyp/nvhe/trace.c @@ -287,3 +287,20 @@ void __tracing_update_clock(u32 mult, u32 shift, u64 e= poch_ns, u64 epoch_cyc) /* ...we can now override the old one and swap. */ trace_clock_update(mult, shift, epoch_ns, epoch_cyc); } + +int __tracing_reset(unsigned int cpu) +{ + int ret =3D -ENODEV; + + if (cpu >=3D hyp_nr_cpus) + return -EINVAL; + + hyp_spin_lock(&trace_buffer.lock); + + if (hyp_trace_buffer_loaded(&trace_buffer)) + ret =3D simple_ring_buffer_reset(per_cpu_ptr(trace_buffer.simple_rbs, cp= u)); + + hyp_spin_unlock(&trace_buffer.lock); + + return ret; +} diff --git a/arch/arm64/kvm/hyp_trace.c b/arch/arm64/kvm/hyp_trace.c index 1e5fc27f0e9d..09bc192e3514 100644 --- a/arch/arm64/kvm/hyp_trace.c +++ b/arch/arm64/kvm/hyp_trace.c @@ -313,7 +313,7 @@ static int hyp_trace_swap_reader_page(unsigned int cpu,= void *priv) =20 static int hyp_trace_reset(unsigned int cpu, void *priv) { - return 0; + return kvm_call_hyp_nvhe(__tracing_reset, cpu); } =20 static int hyp_trace_enable_event(unsigned short id, bool enable, void *pr= iv) --=20 2.52.0.457.g6b5491de43-goog