Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
KVM: arm64: Add trace reset to the nVHE/pKVM hyp
Make the hypervisor reset either the whole tracing buffer or a specific
ring-buffer, on remotes/hypervisor/trace or per_cpu/<cpu>/trace write
access.
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://patch.msgid.link/20260309162516.2623589-27-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
authored by
Vincent Donnefort
and committed by
Marc Zyngier
2194d317
b2288891
+29
-1
+1
arch/arm64/include/asm/kvm_asm.h
+1
arch/arm64/include/asm/kvm_asm.h
+2
arch/arm64/kvm/hyp/include/nvhe/trace.h
+2
arch/arm64/kvm/hyp/include/nvhe/trace.h
···
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int __tracing_enable(bool enable);
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int __tracing_swap_reader(unsigned int cpu);
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void __tracing_update_clock(u32 mult, u32 shift, u64 epoch_ns, u64 epoch_cyc);
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+
int __tracing_reset(unsigned int cpu);
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#else
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static inline void *tracing_reserve_entry(unsigned long length) { return NULL; }
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static inline void tracing_commit_entry(void) { }
···
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static inline int __tracing_enable(bool enable) { return -ENODEV; }
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static inline int __tracing_swap_reader(unsigned int cpu) { return -ENODEV; }
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static inline void __tracing_update_clock(u32 mult, u32 shift, u64 epoch_ns, u64 epoch_cyc) { }
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static inline int __tracing_reset(unsigned int cpu) { return -ENODEV; }
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#endif
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#endif
+8
arch/arm64/kvm/hyp/nvhe/hyp-main.c
+8
arch/arm64/kvm/hyp/nvhe/hyp-main.c
···
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__tracing_update_clock(mult, shift, epoch_ns, epoch_cyc);
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}
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static void handle___tracing_reset(struct kvm_cpu_context *host_ctxt)
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{
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DECLARE_REG(unsigned int, cpu, host_ctxt, 1);
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cpu_reg(host_ctxt, 1) = __tracing_reset(cpu);
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}
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typedef void (*hcall_t)(struct kvm_cpu_context *);
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#define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
···
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HANDLE_FUNC(__tracing_enable),
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HANDLE_FUNC(__tracing_swap_reader),
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HANDLE_FUNC(__tracing_update_clock),
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HANDLE_FUNC(__tracing_reset),
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};
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static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
+17
arch/arm64/kvm/hyp/nvhe/trace.c
+17
arch/arm64/kvm/hyp/nvhe/trace.c
···
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/* ...we can now override the old one and swap. */
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trace_clock_update(mult, shift, epoch_ns, epoch_cyc);
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}
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+
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int __tracing_reset(unsigned int cpu)
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{
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int ret = -ENODEV;
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if (cpu >= hyp_nr_cpus)
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return -EINVAL;
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hyp_spin_lock(&trace_buffer.lock);
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if (hyp_trace_buffer_loaded(&trace_buffer))
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ret = simple_ring_buffer_reset(per_cpu_ptr(trace_buffer.simple_rbs, cpu));
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hyp_spin_unlock(&trace_buffer.lock);
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return ret;
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}