Re: [PATCH v1 17/55] KVM: PPC: Book3S HV P9: Implement PMU save/restore in C
From: Athira Rajeev <hidden>
Date: 2021-08-09 03:04:37
quoted hunk ↗ jump to hunk
On 26-Jul-2021, at 9:19 AM, Nicholas Piggin [off-list ref] wrote: Implement the P9 path PMU save/restore code in C, and remove the POWER9/10 code from the P7/8 path assembly. -449 cycles (8533) POWER9 virt-mode NULL hcall Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/include/asm/asm-prototypes.h | 5 - arch/powerpc/kvm/book3s_hv.c | 205 ++++++++++++++++++++-- arch/powerpc/kvm/book3s_hv_interrupts.S | 13 +- arch/powerpc/kvm/book3s_hv_rmhandlers.S | 43 +---- 4 files changed, 200 insertions(+), 66 deletions(-)diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h index 222823861a67..41b8a1e1144a 100644 --- a/arch/powerpc/include/asm/asm-prototypes.h +++ b/arch/powerpc/include/asm/asm-prototypes.h@@ -141,11 +141,6 @@ static inline void kvmppc_restore_tm_hv(struct kvm_vcpu *vcpu, u64 msr,bool preserve_nv) { } #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ -void kvmhv_save_host_pmu(void); -void kvmhv_load_host_pmu(void); -void kvmhv_save_guest_pmu(struct kvm_vcpu *vcpu, bool pmu_in_use); -void kvmhv_load_guest_pmu(struct kvm_vcpu *vcpu); - void kvmppc_p9_enter_guest(struct kvm_vcpu *vcpu); long kvmppc_h_set_dabr(struct kvm_vcpu *vcpu, unsigned long dabr);diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 2eef708c4354..d20b579ddcdf 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c@@ -3735,6 +3735,188 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)trace_kvmppc_run_core(vc, 1); } +/* + * Privileged (non-hypervisor) host registers to save. + */ +struct p9_host_os_sprs { + unsigned long dscr; + unsigned long tidr; + unsigned long iamr; + unsigned long amr; + unsigned long fscr; + + unsigned int pmc1; + unsigned int pmc2; + unsigned int pmc3; + unsigned int pmc4; + unsigned int pmc5; + unsigned int pmc6; + unsigned long mmcr0; + unsigned long mmcr1; + unsigned long mmcr2; + unsigned long mmcr3; + unsigned long mmcra; + unsigned long siar; + unsigned long sier1; + unsigned long sier2; + unsigned long sier3; + unsigned long sdar; +}; + +static void freeze_pmu(unsigned long mmcr0, unsigned long mmcra) +{ + if (!(mmcr0 & MMCR0_FC)) + goto do_freeze; + if (mmcra & MMCRA_SAMPLE_ENABLE) + goto do_freeze; + if (cpu_has_feature(CPU_FTR_ARCH_31)) { + if (!(mmcr0 & MMCR0_PMCCEXT)) + goto do_freeze; + if (!(mmcra & MMCRA_BHRB_DISABLE)) + goto do_freeze; + } + return; + +do_freeze: + mmcr0 = MMCR0_FC; + mmcra = 0; + if (cpu_has_feature(CPU_FTR_ARCH_31)) { + mmcr0 |= MMCR0_PMCCEXT; + mmcra = MMCRA_BHRB_DISABLE; + } + + mtspr(SPRN_MMCR0, mmcr0); + mtspr(SPRN_MMCRA, mmcra); + isync(); +} +
Hi Nick, After feezing pmu, do we need to clear “pmcregs_in_use” as well? Also can’t we unconditionally do the MMCR0/MMCRA/ freeze settings in here ? do we need the if conditions for FC/PMCCEXT/BHRB ? Thanks Athira
quoted hunk ↗ jump to hunk
+static void save_p9_host_pmu(struct p9_host_os_sprs *host_os_sprs) +{ + if (ppc_get_pmu_inuse()) { + /* + * It might be better to put PMU handling (at least for the + * host) in the perf subsystem because it knows more about what + * is being used. + */ + + /* POWER9, POWER10 do not implement HPMC or SPMC */ + + host_os_sprs->mmcr0 = mfspr(SPRN_MMCR0); + host_os_sprs->mmcra = mfspr(SPRN_MMCRA); + + freeze_pmu(host_os_sprs->mmcr0, host_os_sprs->mmcra); + + host_os_sprs->pmc1 = mfspr(SPRN_PMC1); + host_os_sprs->pmc2 = mfspr(SPRN_PMC2); + host_os_sprs->pmc3 = mfspr(SPRN_PMC3); + host_os_sprs->pmc4 = mfspr(SPRN_PMC4); + host_os_sprs->pmc5 = mfspr(SPRN_PMC5); + host_os_sprs->pmc6 = mfspr(SPRN_PMC6); + host_os_sprs->mmcr1 = mfspr(SPRN_MMCR1); + host_os_sprs->mmcr2 = mfspr(SPRN_MMCR2); + host_os_sprs->sdar = mfspr(SPRN_SDAR); + host_os_sprs->siar = mfspr(SPRN_SIAR); + host_os_sprs->sier1 = mfspr(SPRN_SIER); + + if (cpu_has_feature(CPU_FTR_ARCH_31)) { + host_os_sprs->mmcr3 = mfspr(SPRN_MMCR3); + host_os_sprs->sier2 = mfspr(SPRN_SIER2); + host_os_sprs->sier3 = mfspr(SPRN_SIER3); + } + } +} + +static void load_p9_guest_pmu(struct kvm_vcpu *vcpu) +{ + mtspr(SPRN_PMC1, vcpu->arch.pmc[0]); + mtspr(SPRN_PMC2, vcpu->arch.pmc[1]); + mtspr(SPRN_PMC3, vcpu->arch.pmc[2]); + mtspr(SPRN_PMC4, vcpu->arch.pmc[3]); + mtspr(SPRN_PMC5, vcpu->arch.pmc[4]); + mtspr(SPRN_PMC6, vcpu->arch.pmc[5]); + mtspr(SPRN_MMCR1, vcpu->arch.mmcr[1]); + mtspr(SPRN_MMCR2, vcpu->arch.mmcr[2]); + mtspr(SPRN_SDAR, vcpu->arch.sdar); + mtspr(SPRN_SIAR, vcpu->arch.siar); + mtspr(SPRN_SIER, vcpu->arch.sier[0]); + + if (cpu_has_feature(CPU_FTR_ARCH_31)) { + mtspr(SPRN_MMCR3, vcpu->arch.mmcr[3]); + mtspr(SPRN_SIER2, vcpu->arch.sier[1]); + mtspr(SPRN_SIER3, vcpu->arch.sier[2]); + } + + /* Set MMCRA then MMCR0 last */ + mtspr(SPRN_MMCRA, vcpu->arch.mmcra); + mtspr(SPRN_MMCR0, vcpu->arch.mmcr[0]); + /* No isync necessary because we're starting counters */ +} + +static void save_p9_guest_pmu(struct kvm_vcpu *vcpu) +{ + struct lppaca *lp; + int save_pmu = 1; + + lp = vcpu->arch.vpa.pinned_addr; + if (lp) + save_pmu = lp->pmcregs_in_use; + + if (save_pmu) { + vcpu->arch.mmcr[0] = mfspr(SPRN_MMCR0); + vcpu->arch.mmcra = mfspr(SPRN_MMCRA); + + freeze_pmu(vcpu->arch.mmcr[0], vcpu->arch.mmcra); + + vcpu->arch.pmc[0] = mfspr(SPRN_PMC1); + vcpu->arch.pmc[1] = mfspr(SPRN_PMC2); + vcpu->arch.pmc[2] = mfspr(SPRN_PMC3); + vcpu->arch.pmc[3] = mfspr(SPRN_PMC4); + vcpu->arch.pmc[4] = mfspr(SPRN_PMC5); + vcpu->arch.pmc[5] = mfspr(SPRN_PMC6); + vcpu->arch.mmcr[1] = mfspr(SPRN_MMCR1); + vcpu->arch.mmcr[2] = mfspr(SPRN_MMCR2); + vcpu->arch.sdar = mfspr(SPRN_SDAR); + vcpu->arch.siar = mfspr(SPRN_SIAR); + vcpu->arch.sier[0] = mfspr(SPRN_SIER); + + if (cpu_has_feature(CPU_FTR_ARCH_31)) { + vcpu->arch.mmcr[3] = mfspr(SPRN_MMCR3); + vcpu->arch.sier[1] = mfspr(SPRN_SIER2); + vcpu->arch.sier[2] = mfspr(SPRN_SIER3); + } + } else { + freeze_pmu(mfspr(SPRN_MMCR0), mfspr(SPRN_MMCRA)); + } +} + +static void load_p9_host_pmu(struct p9_host_os_sprs *host_os_sprs) +{ + if (ppc_get_pmu_inuse()) { + mtspr(SPRN_PMC1, host_os_sprs->pmc1); + mtspr(SPRN_PMC2, host_os_sprs->pmc2); + mtspr(SPRN_PMC3, host_os_sprs->pmc3); + mtspr(SPRN_PMC4, host_os_sprs->pmc4); + mtspr(SPRN_PMC5, host_os_sprs->pmc5); + mtspr(SPRN_PMC6, host_os_sprs->pmc6); + mtspr(SPRN_MMCR1, host_os_sprs->mmcr1); + mtspr(SPRN_MMCR2, host_os_sprs->mmcr2); + mtspr(SPRN_SDAR, host_os_sprs->sdar); + mtspr(SPRN_SIAR, host_os_sprs->siar); + mtspr(SPRN_SIER, host_os_sprs->sier1); + + if (cpu_has_feature(CPU_FTR_ARCH_31)) { + mtspr(SPRN_MMCR3, host_os_sprs->mmcr3); + mtspr(SPRN_SIER2, host_os_sprs->sier2); + mtspr(SPRN_SIER3, host_os_sprs->sier3); + } + + /* Set MMCRA then MMCR0 last */ + mtspr(SPRN_MMCRA, host_os_sprs->mmcra); + mtspr(SPRN_MMCR0, host_os_sprs->mmcr0); + isync(); + } +} + static void load_spr_state(struct kvm_vcpu *vcpu) { mtspr(SPRN_DSCR, vcpu->arch.dscr);@@ -3777,17 +3959,6 @@ static void store_spr_state(struct kvm_vcpu *vcpu)vcpu->arch.dscr = mfspr(SPRN_DSCR); } -/* - * Privileged (non-hypervisor) host registers to save. - */ -struct p9_host_os_sprs { - unsigned long dscr; - unsigned long tidr; - unsigned long iamr; - unsigned long amr; - unsigned long fscr; -}; - static void save_p9_host_os_sprs(struct p9_host_os_sprs *host_os_sprs) { host_os_sprs->dscr = mfspr(SPRN_DSCR);@@ -3835,7 +4006,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,struct p9_host_os_sprs host_os_sprs; s64 dec; u64 tb, next_timer; - int trap, save_pmu; + int trap; WARN_ON_ONCE(vcpu->arch.ceded);@@ -3848,7 +4019,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,save_p9_host_os_sprs(&host_os_sprs); - kvmhv_save_host_pmu(); /* saves it to PACA kvm_hstate */ + save_p9_host_pmu(&host_os_sprs); kvmppc_subcore_enter_guest();@@ -3878,7 +4049,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,barrier(); } #endif - kvmhv_load_guest_pmu(vcpu); + load_p9_guest_pmu(vcpu); msr_check_and_set(MSR_FP | MSR_VEC | MSR_VSX); load_fp_state(&vcpu->arch.fp);@@ -4000,16 +4171,14 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) kvmppc_save_tm_hv(vcpu, vcpu->arch.shregs.msr, true); - save_pmu = 1; if (vcpu->arch.vpa.pinned_addr) { struct lppaca *lp = vcpu->arch.vpa.pinned_addr; u32 yield_count = be32_to_cpu(lp->yield_count) + 1; lp->yield_count = cpu_to_be32(yield_count); vcpu->arch.vpa.dirty = 1; - save_pmu = lp->pmcregs_in_use; } - kvmhv_save_guest_pmu(vcpu, save_pmu); + save_p9_guest_pmu(vcpu); #ifdef CONFIG_PPC_PSERIES if (kvmhv_on_pseries()) { barrier();@@ -4025,7 +4194,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,mtspr(SPRN_SPRG_VDSO_WRITE, local_paca->sprg_vdso); - kvmhv_load_host_pmu(); + load_p9_host_pmu(&host_os_sprs); kvmppc_subcore_exit_guest();diff --git a/arch/powerpc/kvm/book3s_hv_interrupts.S b/arch/powerpc/kvm/book3s_hv_interrupts.S index 4444f83cb133..59d89e4b154a 100644 --- a/arch/powerpc/kvm/book3s_hv_interrupts.S +++ b/arch/powerpc/kvm/book3s_hv_interrupts.S@@ -104,7 +104,10 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)mtlr r0 blr -_GLOBAL(kvmhv_save_host_pmu) +/* + * void kvmhv_save_host_pmu(void) + */ +kvmhv_save_host_pmu: BEGIN_FTR_SECTION /* Work around P8 PMAE bug */ li r3, -1@@ -138,14 +141,6 @@ BEGIN_FTR_SECTIONstd r8, HSTATE_MMCR2(r13) std r9, HSTATE_SIER(r13) END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) -BEGIN_FTR_SECTION - mfspr r5, SPRN_MMCR3 - mfspr r6, SPRN_SIER2 - mfspr r7, SPRN_SIER3 - std r5, HSTATE_MMCR3(r13) - std r6, HSTATE_SIER2(r13) - std r7, HSTATE_SIER3(r13) -END_FTR_SECTION_IFSET(CPU_FTR_ARCH_31) mfspr r3, SPRN_PMC1 mfspr r5, SPRN_PMC2 mfspr r6, SPRN_PMC3diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 9021052f1579..551ce223b40c 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S@@ -2738,10 +2738,11 @@ kvmppc_msr_interrupt:blr /* + * void kvmhv_load_guest_pmu(struct kvm_vcpu *vcpu) + * * Load up guest PMU state. R3 points to the vcpu struct. */ -_GLOBAL(kvmhv_load_guest_pmu) -EXPORT_SYMBOL_GPL(kvmhv_load_guest_pmu) +kvmhv_load_guest_pmu: mr r4, r3 mflr r0 li r3, 1@@ -2775,27 +2776,17 @@ END_FTR_SECTION_IFSET(CPU_FTR_PMAO_BUG)mtspr SPRN_MMCRA, r6 mtspr SPRN_SIAR, r7 mtspr SPRN_SDAR, r8 -BEGIN_FTR_SECTION - ld r5, VCPU_MMCR + 24(r4) - ld r6, VCPU_SIER + 8(r4) - ld r7, VCPU_SIER + 16(r4) - mtspr SPRN_MMCR3, r5 - mtspr SPRN_SIER2, r6 - mtspr SPRN_SIER3, r7 -END_FTR_SECTION_IFSET(CPU_FTR_ARCH_31) BEGIN_FTR_SECTION ld r5, VCPU_MMCR + 16(r4) ld r6, VCPU_SIER(r4) mtspr SPRN_MMCR2, r5 mtspr SPRN_SIER, r6 -BEGIN_FTR_SECTION_NESTED(96) lwz r7, VCPU_PMC + 24(r4) lwz r8, VCPU_PMC + 28(r4) ld r9, VCPU_MMCRS(r4) mtspr SPRN_SPMC1, r7 mtspr SPRN_SPMC2, r8 mtspr SPRN_MMCRS, r9 -END_FTR_SECTION_NESTED(CPU_FTR_ARCH_300, 0, 96) END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) mtspr SPRN_MMCR0, r3 isync@@ -2803,10 +2794,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)blr /* + * void kvmhv_load_host_pmu(void) + * * Reload host PMU state saved in the PACA by kvmhv_save_host_pmu. */ -_GLOBAL(kvmhv_load_host_pmu) -EXPORT_SYMBOL_GPL(kvmhv_load_host_pmu) +kvmhv_load_host_pmu: mflr r0 lbz r4, PACA_PMCINUSE(r13) /* is the host using the PMU? */ cmpwi r4, 0@@ -2844,25 +2836,18 @@ BEGIN_FTR_SECTIONmtspr SPRN_MMCR2, r8 mtspr SPRN_SIER, r9 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) -BEGIN_FTR_SECTION - ld r5, HSTATE_MMCR3(r13) - ld r6, HSTATE_SIER2(r13) - ld r7, HSTATE_SIER3(r13) - mtspr SPRN_MMCR3, r5 - mtspr SPRN_SIER2, r6 - mtspr SPRN_SIER3, r7 -END_FTR_SECTION_IFSET(CPU_FTR_ARCH_31) mtspr SPRN_MMCR0, r3 isync mtlr r0 23: blr /* + * void kvmhv_save_guest_pmu(struct kvm_vcpu *vcpu, bool pmu_in_use) + * * Save guest PMU state into the vcpu struct. * r3 = vcpu, r4 = full save flag (PMU in use flag set in VPA) */ -_GLOBAL(kvmhv_save_guest_pmu) -EXPORT_SYMBOL_GPL(kvmhv_save_guest_pmu) +kvmhv_save_guest_pmu: mr r9, r3 mr r8, r4 BEGIN_FTR_SECTION@@ -2911,14 +2896,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)BEGIN_FTR_SECTION std r10, VCPU_MMCR + 16(r9) END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) -BEGIN_FTR_SECTION - mfspr r5, SPRN_MMCR3 - mfspr r6, SPRN_SIER2 - mfspr r7, SPRN_SIER3 - std r5, VCPU_MMCR + 24(r9) - std r6, VCPU_SIER + 8(r9) - std r7, VCPU_SIER + 16(r9) -END_FTR_SECTION_IFSET(CPU_FTR_ARCH_31) std r7, VCPU_SIAR(r9) std r8, VCPU_SDAR(r9) mfspr r3, SPRN_PMC1@@ -2936,7 +2913,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_31)BEGIN_FTR_SECTION mfspr r5, SPRN_SIER std r5, VCPU_SIER(r9) -BEGIN_FTR_SECTION_NESTED(96) mfspr r6, SPRN_SPMC1 mfspr r7, SPRN_SPMC2 mfspr r8, SPRN_MMCRS@@ -2945,7 +2921,6 @@ BEGIN_FTR_SECTION_NESTED(96)std r8, VCPU_MMCRS(r9) lis r4, 0x8000 mtspr SPRN_MMCRS, r4 -END_FTR_SECTION_NESTED(CPU_FTR_ARCH_300, 0, 96) END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) 22: blr -- 2.23.0