From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: [PATCH v3 12/12] KVM: arm64: add trace points for guest_debug debug Date: Fri, 8 May 2015 19:25:03 +0200 Message-ID: <20150508172503.GM24744@cbox> References: <1430929407-3487-1-git-send-email-alex.bennee@linaro.org> <1430989647-22501-5-git-send-email-alex.bennee@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Cc: Catalin Marinas , kvm@vger.kernel.org, marc.zyngier@arm.com, jan.kiszka@siemens.com, Will Deacon , open list , dahi@linux.vnet.ibm.com, zhichao.huang@linaro.org, r65777@freescale.com, pbonzini@redhat.com, bp@suse.de, Gleb Natapov , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org To: Alex =?iso-8859-1?Q?Benn=E9e?= Return-path: Content-Disposition: inline In-Reply-To: <1430989647-22501-5-git-send-email-alex.bennee@linaro.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org On Thu, May 07, 2015 at 10:07:15AM +0100, Alex Benn=E9e wrote: > This includes trace points for: > kvm_arch_setup_guest_debug > kvm_arch_clear_guest_debug > kvm_handle_guest_debug > = > I've also added some generic register setting trace events and also a > trace point to dump the array of hardware registers. > = > Signed-off-by: Alex Benn=E9e > = > --- > v3 > - add trace event for debug access. > - remove short trace #define, rename trace events > - use __print_array with fixed array instead of own func > - rationalise trace points (only one per register changed) > - add vcpu ptr to the debug_setup trace > - remove :: in prints > = > diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c > index dc8bca8..08e1b83 100644 > --- a/arch/arm64/kvm/debug.c > +++ b/arch/arm64/kvm/debug.c > @@ -24,6 +24,8 @@ > #include > #include > = > +#include "trace.h" > + > /* These are the bits of MDSCR_EL1 we may manipulate */ > #define MDSCR_EL1_DEBUG_MASK (DBG_MDSCR_SS | \ > DBG_MDSCR_KDE | \ > @@ -44,6 +46,11 @@ static void save_guest_debug_regs(struct kvm_vcpu *vcp= u) > { > vcpu->arch.guest_debug_state.pstate =3D *vcpu_cpsr(vcpu); > vcpu->arch.guest_debug_state.mdscr_el1 =3D vcpu_sys_reg(vcpu, MDSCR_EL1= ); > + > + trace_kvm_arm_set_dreg32("Saved PSTATE", > + vcpu->arch.guest_debug_state.pstate); > + trace_kvm_arm_set_dreg32("Saved MDSCR_EL1", > + vcpu->arch.guest_debug_state.mdscr_el1); wouldn't it make sense to turn these into a single tracepoint with two parameters? > } > = > static void restore_guest_debug_regs(struct kvm_vcpu *vcpu) > @@ -51,6 +58,10 @@ static void restore_guest_debug_regs(struct kvm_vcpu *= vcpu) > *vcpu_cpsr(vcpu) |=3D > (vcpu->arch.guest_debug_state.pstate & SPSR_DEBUG_MASK); > vcpu_sys_reg(vcpu, MDSCR_EL1) =3D vcpu->arch.guest_debug_state.mdscr_el= 1; > + > + trace_kvm_arm_set_dreg32("Restored PSTATE", *vcpu_cpsr(vcpu)); > + trace_kvm_arm_set_dreg32("Restored MDSCR_EL1", > + vcpu_sys_reg(vcpu, MDSCR_EL1)); ditto > } > = > /** > @@ -92,6 +103,8 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) > { > bool trap_debug =3D !(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY); > = > + trace_kvm_arm_setup_debug(vcpu, vcpu->guest_debug); > + > vcpu->arch.mdcr_el2 =3D __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK; > vcpu->arch.mdcr_el2 |=3D (MDCR_EL2_TPM | > MDCR_EL2_TPMCR | > @@ -121,6 +134,8 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) > vcpu_sys_reg(vcpu, MDSCR_EL1) &=3D ~DBG_MDSCR_SS; > } > = > + trace_kvm_arm_set_dreg32("SPSR_EL2", *vcpu_cpsr(vcpu)); > + > /* > * HW Break/Watch points > * > @@ -138,6 +153,14 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) > vcpu->arch.debug_ptr =3D &vcpu->arch.external_debug_state; > vcpu->arch.debug_flags |=3D KVM_ARM64_DEBUG_DIRTY; > trap_debug =3D true; > + > + trace_kvm_arm_set_regset("BKPTS", get_num_brps(), > + &vcpu->arch.debug_ptr->dbg_bcr[0], > + &vcpu->arch.debug_ptr->dbg_bvr[0]); > + > + trace_kvm_arm_set_regset("WAPTS", get_num_wrps(), > + &vcpu->arch.debug_ptr->dbg_wcr[0], > + &vcpu->arch.debug_ptr->dbg_wvr[0]); feels like this should also be a single tracepoint > } > = > } else { > @@ -155,10 +178,15 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) > vcpu->arch.mdcr_el2 |=3D MDCR_EL2_TDA; > else > vcpu->arch.mdcr_el2 &=3D ~MDCR_EL2_TDA; > + > + trace_kvm_arm_set_dreg32("MDCR_EL2", vcpu->arch.mdcr_el2); > + trace_kvm_arm_set_dreg32("MDSCR_EL1", vcpu_sys_reg(vcpu, MDSCR_EL1)); > } > = > void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) > { > + trace_kvm_arm_clear_debug(vcpu->guest_debug); > + > if (vcpu->guest_debug) { > restore_guest_debug_regs(vcpu); > = > @@ -169,6 +197,14 @@ void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) > if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) { > vcpu->arch.debug_ptr =3D (struct kvm_guest_debug_arch *) > &vcpu_sys_reg(vcpu, DBGBCR0_EL1); > + > + trace_kvm_arm_set_regset("BKPTS", get_num_brps(), > + &vcpu->arch.debug_ptr->dbg_bcr[0], > + &vcpu->arch.debug_ptr->dbg_bvr[0]); > + > + trace_kvm_arm_set_regset("WAPTS", get_num_wrps(), > + &vcpu->arch.debug_ptr->dbg_wcr[0], > + &vcpu->arch.debug_ptr->dbg_wvr[0]); ditto > } > } > } > diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c > index 68a0759..c93b95e 100644 > --- a/arch/arm64/kvm/handle_exit.c > +++ b/arch/arm64/kvm/handle_exit.c > @@ -99,6 +99,8 @@ static int kvm_handle_guest_debug(struct kvm_vcpu *vcpu= , struct kvm_run *run) > u32 hsr =3D kvm_vcpu_get_hsr(vcpu); > int ret =3D 0; > = > + trace_kvm_handle_guest_debug(*vcpu_pc(vcpu), hsr); > + does this provide anything beyond the generic handle_exit tracepoint? > run->exit_reason =3D KVM_EXIT_DEBUG; > run->debug.arch.hsr =3D hsr; > = > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index 95f422f..ec803ad 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -38,6 +38,8 @@ > = > #include "sys_regs.h" > = > +#include "trace.h" > + > /* > * All of this file is extremly similar to the ARM coproc.c, but the > * types are different. My gut feeling is that it should be pretty > @@ -227,6 +229,9 @@ static bool trap_debug_regs(struct kvm_vcpu *vcpu, > const struct sys_reg_params *p, > const struct sys_reg_desc *r) > { > + trace_trap_debug_regs(r->reg, p->is_write, > + p->is_write?*vcpu_reg(vcpu, p->Rt):0); > + > if (vcpu->guest_debug && shadow_debug_reg(vcpu, p, r)) > return true; > = > diff --git a/arch/arm64/kvm/trace.h b/arch/arm64/kvm/trace.h > index 157416e9..62e6b76 100644 > --- a/arch/arm64/kvm/trace.h > +++ b/arch/arm64/kvm/trace.h > @@ -44,6 +44,113 @@ TRACE_EVENT(kvm_hvc_arm64, > __entry->vcpu_pc, __entry->r0, __entry->imm) > ); > = > +TRACE_EVENT(kvm_handle_guest_debug, > + TP_PROTO(unsigned long vcpu_pc, u32 hsr), > + TP_ARGS(vcpu_pc, hsr), > + > + TP_STRUCT__entry( > + __field(unsigned long, vcpu_pc) > + __field(u32, hsr) > + ), > + > + TP_fast_assign( > + __entry->vcpu_pc =3D vcpu_pc; > + __entry->hsr =3D hsr; > + ), > + > + TP_printk("debug exception at 0x%08lx (HSR: 0x%08x)", > + __entry->vcpu_pc, __entry->hsr) > +); > + > + > +TRACE_EVENT(kvm_arm_setup_debug, > + TP_PROTO(struct kvm_vcpu *vcpu, __u32 guest_debug), > + TP_ARGS(vcpu, guest_debug), > + > + TP_STRUCT__entry( > + __field(struct kvm_vcpu *, vcpu) > + __field(__u32, guest_debug) > + ), > + > + TP_fast_assign( > + __entry->vcpu =3D vcpu; > + __entry->guest_debug =3D guest_debug; > + ), > + > + TP_printk("vcpu: %p, flags: 0x%08x", __entry->vcpu, __entry->guest_debu= g) > +); > + > +TRACE_EVENT(kvm_arm_clear_debug, > + TP_PROTO(__u32 guest_debug), > + TP_ARGS(guest_debug), > + > + TP_STRUCT__entry( > + __field(__u32, guest_debug) > + ), > + > + TP_fast_assign( > + __entry->guest_debug =3D guest_debug; > + ), > + > + TP_printk("flags: 0x%08x", __entry->guest_debug) > +); > + > +TRACE_EVENT(kvm_arm_set_dreg32, > + TP_PROTO(const char *name, __u32 value), > + TP_ARGS(name, value), > + > + TP_STRUCT__entry( > + __field(const char *, name) > + __field(__u32, value) > + ), > + > + TP_fast_assign( > + __entry->name =3D name; > + __entry->value =3D value; > + ), > + > + TP_printk("%s: 0x%08x", __entry->name, __entry->value) > +); > + > +TRACE_EVENT(kvm_arm_set_regset, > + TP_PROTO(const char *type, int len, __u64 *control, __u64 *value), > + TP_ARGS(type, len, control, value), > + TP_STRUCT__entry( > + __field(const char *, name) > + __field(int, len) > + __array(u64, ctrls, 16) > + __array(u64, values, 16) > + ), > + TP_fast_assign( > + __entry->name =3D type; > + __entry->len =3D len; > + memcpy(__entry->ctrls, control, len << 3); > + memcpy(__entry->values, value, len << 3); > + ), > + TP_printk("%d %s CTRL:%s VALUE:%s", __entry->len, __entry->name, > + __print_array(__entry->ctrls, __entry->len, sizeof(__u64)), > + __print_array(__entry->values, __entry->len, sizeof(__u64))) > +); > + > +TRACE_EVENT(trap_debug_regs, > + TP_PROTO(int reg, bool is_write, u64 write_value), > + TP_ARGS(reg, is_write, write_value), > + > + TP_STRUCT__entry( > + __field(int, reg) > + __field(bool, is_write) > + __field(u64, write_value) > + ), > + > + TP_fast_assign( > + __entry->reg =3D reg; > + __entry->is_write =3D is_write; > + __entry->write_value =3D write_value; > + ), > + > + TP_printk("%s reg %d (0x%08llx)", __entry->is_write?"write to":"read fr= om", __entry->reg, __entry->write_value) > +); > + > #endif /* _TRACE_ARM64_KVM_H */ > = > #undef TRACE_INCLUDE_PATH > -- = > 2.3.5 > = Thanks, -Christoffer