From b5905dc12ed4254f7e0aac62bab48f002181f639 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Sun, 30 Aug 2015 15:55:22 +0200 Subject: [PATCH] arm/arm64: KVM: Improve kvm_exit tracepoint The ARM architecture only saves the exit class to the HSR (ESR_EL2 for arm64) on synchronous exceptions, not on asynchronous exceptions like an IRQ. However, we only report the exception class on kvm_exit, which is confusing because an IRQ looks like it exited at some PC with the same reason as the previous exit. Add a lookup table for the exception index and prepend the kvm_exit tracepoint text with the exception type to clarify this situation. Also resolve the exception class (EC) to a human-friendly text version so the trace output becomes immediately usable for debugging this code. Cc: Wei Huang Signed-off-by: Christoffer Dall --- arch/arm/include/asm/kvm_arm.h | 20 ++++++++++++++++++++ arch/arm/kvm/arm.c | 2 +- arch/arm/kvm/trace.h | 10 +++++++--- arch/arm64/include/asm/kvm_arm.h | 16 ++++++++++++++++ 4 files changed, 44 insertions(+), 4 deletions(-) diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h index d995821f1698..dc641ddf0784 100644 --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -218,4 +218,24 @@ #define HSR_DABT_CM (1U << 8) #define HSR_DABT_EA (1U << 9) +#define kvm_arm_exception_type \ + {0, "RESET" }, \ + {1, "UNDEFINED" }, \ + {2, "SOFTWARE" }, \ + {3, "PREF_ABORT" }, \ + {4, "DATA_ABORT" }, \ + {5, "IRQ" }, \ + {6, "FIQ" }, \ + {7, "HVC" } + +#define HSRECN(x) { HSR_EC_##x, #x } + +#define kvm_arm_exception_class \ + HSRECN(UNKNOWN), HSRECN(WFI), HSRECN(CP15_32), HSRECN(CP15_64), \ + HSRECN(CP14_MR), HSRECN(CP14_LS), HSRECN(CP_0_13), HSRECN(CP10_ID), \ + HSRECN(JAZELLE), HSRECN(BXJ), HSRECN(CP14_64), HSRECN(SVC_HYP), \ + HSRECN(HVC), HSRECN(SMC), HSRECN(IABT), HSRECN(IABT_HYP), \ + HSRECN(DABT), HSRECN(DABT_HYP) + + #endif /* __ARM_KVM_ARM_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index ed1574724caf..eab83b2435b8 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -635,7 +635,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) * guest time. */ kvm_guest_exit(); - trace_kvm_exit(kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); + trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); /* * We must sync the timer state before the vgic state so that diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h index 0ec35392d208..c25a88598eb0 100644 --- a/arch/arm/kvm/trace.h +++ b/arch/arm/kvm/trace.h @@ -25,21 +25,25 @@ TRACE_EVENT(kvm_entry, ); TRACE_EVENT(kvm_exit, - TP_PROTO(unsigned int exit_reason, unsigned long vcpu_pc), - TP_ARGS(exit_reason, vcpu_pc), + TP_PROTO(int idx, unsigned int exit_reason, unsigned long vcpu_pc), + TP_ARGS(idx, exit_reason, vcpu_pc), TP_STRUCT__entry( + __field( int, idx ) __field( unsigned int, exit_reason ) __field( unsigned long, vcpu_pc ) ), TP_fast_assign( + __entry->idx = idx; __entry->exit_reason = exit_reason; __entry->vcpu_pc = vcpu_pc; ), - TP_printk("HSR_EC: 0x%04x, PC: 0x%08lx", + TP_printk("%s: HSR_EC: 0x%04x (%s), PC: 0x%08lx", + __print_symbolic(__entry->idx, kvm_arm_exception_type), __entry->exit_reason, + __print_symbolic(__entry->exit_reason, kvm_arm_exception_class), __entry->vcpu_pc) ); diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 9694f2654593..5e6857b6bdc4 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -200,4 +200,20 @@ /* Hyp Prefetch Fault Address Register (HPFAR/HDFAR) */ #define HPFAR_MASK (~UL(0xf)) +#define kvm_arm_exception_type \ + {0, "IRQ" }, \ + {1, "TRAP" } + +#define ECN(x) { ESR_ELx_EC_##x, #x } + +#define kvm_arm_exception_class \ + ECN(UNKNOWN), ECN(WFx), ECN(CP15_32), ECN(CP15_64), ECN(CP14_MR), \ + ECN(CP14_LS), ECN(FP_ASIMD), ECN(CP10_ID), ECN(CP14_64), ECN(SVC64), \ + ECN(HVC64), ECN(SMC64), ECN(SYS64), ECN(IMP_DEF), ECN(IABT_LOW), \ + ECN(IABT_CUR), ECN(PC_ALIGN), ECN(DABT_LOW), ECN(DABT_CUR), \ + ECN(SP_ALIGN), ECN(FP_EXC32), ECN(FP_EXC64), ECN(SERROR), \ + ECN(BREAKPT_LOW), ECN(BREAKPT_CUR), ECN(SOFTSTP_LOW), \ + ECN(SOFTSTP_CUR), ECN(WATCHPT_LOW), ECN(WATCHPT_CUR), \ + ECN(BKPT32), ECN(VECTOR32), ECN(BRK64) + #endif /* __ARM64_KVM_ARM_H__ */ -- 2.20.1