From: Christian Ehrhardt <ehrhardt@xxxxxxxxxxxxxxxxxx> *update to v5* - add exittiming.c to diff content - prefix all exit timing functions with kvmppc to prevent name collisions (was already done for some of the functions, now its consequently done for all of them) - renamed header & c-file and relocated the header from asm to arch/powerpc/kvm - changed the empty define function stubs to empty static inlines - removed unrelated whitespace change and leftover of atomic vm_id - changed debugs filename to lower case and fewer underscores - updated the Kconfig text Other existing kvm statistics are either just counters (kvm_stat) reported for kvm generally or trace based aproaches like kvm_trace. For kvm on powerpc we had the need to track the timings of the different exit types. While this could be achieved parsing data created with a kvm_trace extension this adds too muhc overhead (at least on embedded powerpc) slowing down the workloads we wanted to measure. Therefore this patch adds a in kernel exit timing statistic to the powerpc kvm code. These statistic is available per vm&vcpu under the kvm debugfs directory. As this statistic is low, but still some overhead it can be enabled via a .config entry and should be off by default. Since this patch touched all powerpc kvm_stat code anyway this code is now merged and simpliefied together with the exit timing statistic code (still working with exit timing disabled in .config). An awk script printing the data in a more narrow layout can be found on our wiki pages about the exit timing topic. (http://kvm.qumranet.com/kvmwiki/PowerPC_Exittimings) Here is a sample output how the results look like. processing file timing_boot.log sum of time 8309940 type count min max sum avg stddev % MMIO: 9402 44 1997 1697610 180.5584 155.768 20.43 DCR: 680 41 99 32096 47.2000 7.008 0.39 SIGNAL: 1 98 98 98 98.0000 0.000 0.00 ITLBREAL: 926 8 14 7810 8.4341 0.658 0.09 ITLBVIRT: 3595 18 202 76185 21.1919 4.954 0.92 DTLBREAL: 950 8 16 8891 9.3589 1.427 0.11 DTLBVIRT: 6695 18 282 156727 23.4096 13.781 1.89 SYSCALL: 1801 6 59 11372 6.3143 2.575 0.14 ISI: 116 6 8 764 6.5862 0.588 0.01 DSI: 43 6 7 292 6.7907 0.407 0.00 EMULINST: 65247 7 96 484081 7.4192 1.818 5.83 EMUL_WAIT: 801 659 9200 3721789 4646.4282 1687.218 44.79 EMUL_WRTEE: 66806 7 86 540053 8.0839 1.895 6.50 EMUL_MTSPR: 13415 8 62 111358 8.3010 2.583 1.34 EMUL_MFSPR: 7635 8 61 62772 8.2216 1.921 0.76 EMUL_MTMSR: 5678 8 59 45704 8.0493 1.434 0.55 EMUL_MFMSR: 32853 7 67 267603 8.1455 1.875 3.22 EMUL_TLBSX: 354 9 60 3745 10.5791 3.919 0.05 EMUL_TLBWE: 6403 9 112 99522 15.5430 7.668 1.20 EMUL_RFI: 9515 7 57 71420 7.5060 2.108 0.86 DEC: 290 49 161 15786 54.4345 9.708 0.19 EXTINT: 7 74 75 522 74.5714 0.495 0.01 TIMEINGUEST: 233213 0 3954 893740 3.8323 65.837 10.76 Signed-off-by: Christian Ehrhardt <ehrhardt@xxxxxxxxxxxxxxxxxx> --- [diffstat] include/asm/kvm_host.h | 56 ++++++++++ kernel/asm-offsets.c | 11 ++ kvm/44x_emulate.c | 11 +- kvm/44x_tlb.c | 3 kvm/Kconfig | 11 ++ kvm/Makefile | 1 kvm/booke.c | 36 ++++-- kvm/booke.h | 5 kvm/booke_interrupts.S | 24 ++++ kvm/emulate.c | 4 kvm/powerpc.c | 8 + kvm/timing.c | 262 +++++++++++++++++++++++++++++++++++++++++++++++++ kvm/timing.h | 102 +++++++++++++++++++ 13 files changed, 516 insertions(+), 18 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -71,6 +71,49 @@ struct kvmppc_44x_tlbe { u32 word2; }; +enum kvm_exit_types { + MMIO_EXITS, + DCR_EXITS, + SIGNAL_EXITS, + ITLB_REAL_MISS_EXITS, + ITLB_VIRT_MISS_EXITS, + DTLB_REAL_MISS_EXITS, + DTLB_VIRT_MISS_EXITS, + SYSCALL_EXITS, + ISI_EXITS, + DSI_EXITS, + EMULATED_INST_EXITS, + EMULATED_MTMSRWE_EXITS, + EMULATED_WRTEE_EXITS, + EMULATED_MTSPR_EXITS, + EMULATED_MFSPR_EXITS, + EMULATED_MTMSR_EXITS, + EMULATED_MFMSR_EXITS, + EMULATED_TLBSX_EXITS, + EMULATED_TLBWE_EXITS, + EMULATED_RFI_EXITS, + DEC_EXITS, + EXT_INTR_EXITS, + HALT_WAKEUP, + USR_PR_INST, + FP_UNAVAIL, + DEBUG_EXITS, + TIMEINGUEST, + __NUMBER_OF_KVM_EXIT_TYPES +}; + +#ifdef CONFIG_KVM_EXIT_TIMING +/* allow access to big endian 32bit upper/lower parts and 64bit var */ +struct exit_timing { + union { + u64 tv64; + struct { + u32 tbu, tbl; + } tv32; + }; +}; +#endif + struct kvm_arch { }; @@ -130,6 +173,19 @@ struct kvm_vcpu_arch { u32 dbcr0; u32 dbcr1; +#ifdef CONFIG_KVM_EXIT_TIMING + struct exit_timing timing_exit; + struct exit_timing timing_last_enter; + u32 last_exit_type; + u32 timing_count_type[__NUMBER_OF_KVM_EXIT_TYPES]; + u64 timing_sum_duration[__NUMBER_OF_KVM_EXIT_TYPES]; + u64 timing_sum_quad_duration[__NUMBER_OF_KVM_EXIT_TYPES]; + u64 timing_min_duration[__NUMBER_OF_KVM_EXIT_TYPES]; + u64 timing_max_duration[__NUMBER_OF_KVM_EXIT_TYPES]; + u64 timing_last_exit; + struct dentry *debugfs_exit_timing; +#endif + u32 last_inst; ulong fault_dear; ulong fault_esr; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -381,5 +381,16 @@ int main(void) DEFINE(PTE_SHIFT, PTE_SHIFT); #endif +#ifdef CONFIG_KVM_EXIT_TIMING + DEFINE(VCPU_TIMING_EXIT_TBU, offsetof(struct kvm_vcpu, + arch.timing_exit.tv32.tbu)); + DEFINE(VCPU_TIMING_EXIT_TBL, offsetof(struct kvm_vcpu, + arch.timing_exit.tv32.tbl)); + DEFINE(VCPU_TIMING_LAST_ENTER_TBU, offsetof(struct kvm_vcpu, + arch.timing_last_enter.tv32.tbu)); + DEFINE(VCPU_TIMING_LAST_ENTER_TBL, offsetof(struct kvm_vcpu, + arch.timing_last_enter.tv32.tbl)); +#endif + return 0; } diff --git a/arch/powerpc/kvm/44x_emulate.c b/arch/powerpc/kvm/44x_emulate.c --- a/arch/powerpc/kvm/44x_emulate.c +++ b/arch/powerpc/kvm/44x_emulate.c @@ -22,6 +22,7 @@ #include <asm/dcr-regs.h> #include <asm/disassemble.h> #include <asm/kvm_44x.h> +#include "timing.h" #include "booke.h" #include "44x_tlb.h" @@ -58,11 +59,11 @@ int kvmppc_core_emulate_op(struct kvm_ru int ws; switch (get_op(inst)) { - case OP_RFI: switch (get_xop(inst)) { case XOP_RFI: kvmppc_emul_rfi(vcpu); + kvmppc_set_exit_type(vcpu, EMULATED_RFI_EXITS); *advance = 0; break; @@ -78,10 +79,12 @@ int kvmppc_core_emulate_op(struct kvm_ru case XOP_MFMSR: rt = get_rt(inst); vcpu->arch.gpr[rt] = vcpu->arch.msr; + kvmppc_set_exit_type(vcpu, EMULATED_MFMSR_EXITS); break; case XOP_MTMSR: rs = get_rs(inst); + kvmppc_set_exit_type(vcpu, EMULATED_MTMSR_EXITS); kvmppc_set_msr(vcpu, vcpu->arch.gpr[rs]); break; @@ -89,11 +92,13 @@ int kvmppc_core_emulate_op(struct kvm_ru rs = get_rs(inst); vcpu->arch.msr = (vcpu->arch.msr & ~MSR_EE) | (vcpu->arch.gpr[rs] & MSR_EE); + kvmppc_set_exit_type(vcpu, EMULATED_WRTEE_EXITS); break; case XOP_WRTEEI: vcpu->arch.msr = (vcpu->arch.msr & ~MSR_EE) | (inst & MSR_EE); + kvmppc_set_exit_type(vcpu, EMULATED_WRTEE_EXITS); break; case XOP_MFDCR: @@ -127,6 +132,7 @@ int kvmppc_core_emulate_op(struct kvm_ru run->dcr.is_write = 0; vcpu->arch.io_gpr = rt; vcpu->arch.dcr_needed = 1; + account_exit(vcpu, DCR_EXITS); emulated = EMULATE_DO_DCR; } @@ -146,6 +152,7 @@ int kvmppc_core_emulate_op(struct kvm_ru run->dcr.data = vcpu->arch.gpr[rs]; run->dcr.is_write = 1; vcpu->arch.dcr_needed = 1; + account_exit(vcpu, DCR_EXITS); emulated = EMULATE_DO_DCR; } @@ -276,6 +283,7 @@ int kvmppc_core_emulate_mtspr(struct kvm return EMULATE_FAIL; } + kvmppc_set_exit_type(vcpu, EMULATED_MTSPR_EXITS); return EMULATE_DONE; } @@ -357,6 +365,7 @@ int kvmppc_core_emulate_mfspr(struct kvm return EMULATE_FAIL; } + kvmppc_set_exit_type(vcpu, EMULATED_MFSPR_EXITS); return EMULATE_DONE; } diff --git a/arch/powerpc/kvm/44x_tlb.c b/arch/powerpc/kvm/44x_tlb.c --- a/arch/powerpc/kvm/44x_tlb.c +++ b/arch/powerpc/kvm/44x_tlb.c @@ -27,6 +27,7 @@ #include <asm/mmu-44x.h> #include <asm/kvm_ppc.h> #include <asm/kvm_44x.h> +#include "timing.h" #include "44x_tlb.h" @@ -457,6 +458,7 @@ int kvmppc_44x_emul_tlbwe(struct kvm_vcp KVMTRACE_5D(GTLB_WRITE, vcpu, gtlb_index, tlbe->tid, tlbe->word0, tlbe->word1, tlbe->word2, handler); + kvmppc_set_exit_type(vcpu, EMULATED_TLBWE_EXITS); return EMULATE_DONE; } @@ -480,5 +482,6 @@ int kvmppc_44x_emul_tlbsx(struct kvm_vcp } vcpu->arch.gpr[rt] = gtlb_index; + kvmppc_set_exit_type(vcpu, EMULATED_TLBSX_EXITS); return EMULATE_DONE; } diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig --- a/arch/powerpc/kvm/Kconfig +++ b/arch/powerpc/kvm/Kconfig @@ -32,6 +32,17 @@ config KVM_440 If unsure, say N. +config KVM_EXIT_TIMING + bool "Detailed exit timing" + depends on KVM + ---help--- + Calculate elapsed time for every exit/enter cycle. A per-vcpu + report is available in debugfs kvm/vm#_vcpu#_timing. + The overhead is relatively small, however it is not recommended for + production environments. + + If unsure, say N. + config KVM_TRACE bool "KVM trace support" depends on KVM && MARKERS && SYSFS diff --git a/arch/powerpc/kvm/Makefile b/arch/powerpc/kvm/Makefile --- a/arch/powerpc/kvm/Makefile +++ b/arch/powerpc/kvm/Makefile @@ -9,6 +9,7 @@ common-objs-$(CONFIG_KVM_TRACE) += $(ad common-objs-$(CONFIG_KVM_TRACE) += $(addprefix ../../../virt/kvm/, kvm_trace.o) kvm-objs := $(common-objs-y) powerpc.o emulate.o +obj-$(CONFIG_KVM_EXIT_TIMING) += timing.o obj-$(CONFIG_KVM) += kvm.o AFLAGS_booke_interrupts.o := -I$(obj) diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -28,6 +28,7 @@ #include <asm/cputable.h> #include <asm/uaccess.h> #include <asm/kvm_ppc.h> +#include "timing.h" #include <asm/cacheflush.h> #include <asm/kvm_44x.h> @@ -185,6 +186,9 @@ int kvmppc_handle_exit(struct kvm_run *r enum emulation_result er; int r = RESUME_HOST; + /* update before a new last_exit_type is rewritten */ + kvmppc_update_timing_stats(vcpu); + local_irq_enable(); run->exit_reason = KVM_EXIT_UNKNOWN; @@ -198,7 +202,7 @@ int kvmppc_handle_exit(struct kvm_run *r break; case BOOKE_INTERRUPT_EXTERNAL: - vcpu->stat.ext_intr_exits++; + account_exit(vcpu, EXT_INTR_EXITS); if (need_resched()) cond_resched(); r = RESUME_GUEST; @@ -208,8 +212,7 @@ int kvmppc_handle_exit(struct kvm_run *r /* Since we switched IVPR back to the host's value, the host * handled this interrupt the moment we enabled interrupts. * Now we just offer it a chance to reschedule the guest. */ - - vcpu->stat.dec_exits++; + account_exit(vcpu, DEC_EXITS); if (need_resched()) cond_resched(); r = RESUME_GUEST; @@ -222,20 +225,21 @@ int kvmppc_handle_exit(struct kvm_run *r vcpu->arch.esr = vcpu->arch.fault_esr; kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_PROGRAM); r = RESUME_GUEST; + account_exit(vcpu, USR_PR_INST); break; } er = kvmppc_emulate_instruction(run, vcpu); switch (er) { case EMULATE_DONE: + /* don't overwrite subtypes, just account kvm_stats */ + account_exit_stat(vcpu, EMULATED_INST_EXITS); /* Future optimization: only reload non-volatiles if * they were actually modified by emulation. */ - vcpu->stat.emulated_inst_exits++; r = RESUME_GUEST_NV; break; case EMULATE_DO_DCR: run->exit_reason = KVM_EXIT_DCR; - vcpu->stat.dcr_exits++; r = RESUME_HOST; break; case EMULATE_FAIL: @@ -255,6 +259,7 @@ int kvmppc_handle_exit(struct kvm_run *r case BOOKE_INTERRUPT_FP_UNAVAIL: kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_FP_UNAVAIL); + account_exit(vcpu, FP_UNAVAIL); r = RESUME_GUEST; break; @@ -262,20 +267,20 @@ int kvmppc_handle_exit(struct kvm_run *r vcpu->arch.dear = vcpu->arch.fault_dear; vcpu->arch.esr = vcpu->arch.fault_esr; kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_DATA_STORAGE); - vcpu->stat.dsi_exits++; + account_exit(vcpu, DSI_EXITS); r = RESUME_GUEST; break; case BOOKE_INTERRUPT_INST_STORAGE: vcpu->arch.esr = vcpu->arch.fault_esr; kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_INST_STORAGE); - vcpu->stat.isi_exits++; + account_exit(vcpu, ISI_EXITS); r = RESUME_GUEST; break; case BOOKE_INTERRUPT_SYSCALL: kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_SYSCALL); - vcpu->stat.syscall_exits++; + account_exit(vcpu, SYSCALL_EXITS); r = RESUME_GUEST; break; @@ -294,7 +299,7 @@ int kvmppc_handle_exit(struct kvm_run *r kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_DTLB_MISS); vcpu->arch.dear = vcpu->arch.fault_dear; vcpu->arch.esr = vcpu->arch.fault_esr; - vcpu->stat.dtlb_real_miss_exits++; + account_exit(vcpu, DTLB_REAL_MISS_EXITS); r = RESUME_GUEST; break; } @@ -312,13 +317,13 @@ int kvmppc_handle_exit(struct kvm_run *r * invoking the guest. */ kvmppc_mmu_map(vcpu, eaddr, vcpu->arch.paddr_accessed, gtlbe->tid, gtlbe->word2, get_tlb_bytes(gtlbe), gtlb_index); - vcpu->stat.dtlb_virt_miss_exits++; + account_exit(vcpu, DTLB_VIRT_MISS_EXITS); r = RESUME_GUEST; } else { /* Guest has mapped and accessed a page which is not * actually RAM. */ r = kvmppc_emulate_mmio(run, vcpu); - vcpu->stat.mmio_exits++; + account_exit(vcpu, MMIO_EXITS); } break; @@ -340,11 +345,11 @@ int kvmppc_handle_exit(struct kvm_run *r if (gtlb_index < 0) { /* The guest didn't have a mapping for it. */ kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_ITLB_MISS); - vcpu->stat.itlb_real_miss_exits++; + account_exit(vcpu, ITLB_REAL_MISS_EXITS); break; } - vcpu->stat.itlb_virt_miss_exits++; + account_exit(vcpu, ITLB_VIRT_MISS_EXITS); gtlbe = &vcpu_44x->guest_tlb[gtlb_index]; gpaddr = tlb_xlate(gtlbe, eaddr); @@ -378,6 +383,7 @@ int kvmppc_handle_exit(struct kvm_run *r mtspr(SPRN_DBSR, dbsr); run->exit_reason = KVM_EXIT_DEBUG; + account_exit(vcpu, DEBUG_EXITS); r = RESUME_HOST; break; } @@ -398,7 +404,7 @@ int kvmppc_handle_exit(struct kvm_run *r if (signal_pending(current)) { run->exit_reason = KVM_EXIT_INTR; r = (-EINTR << 2) | RESUME_HOST | (r & RESUME_FLAG_NV); - vcpu->stat.signal_exits++; + account_exit(vcpu, SIGNAL_EXITS); } } @@ -417,6 +423,8 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu /* Eye-catching number so we know if the guest takes an interrupt * before it's programmed its own IVPR. */ vcpu->arch.ivpr = 0x55550000; + + kvmppc_init_timing_stats(vcpu); return kvmppc_core_vcpu_setup(vcpu); } diff --git a/arch/powerpc/kvm/booke.h b/arch/powerpc/kvm/booke.h --- a/arch/powerpc/kvm/booke.h +++ b/arch/powerpc/kvm/booke.h @@ -22,6 +22,7 @@ #include <linux/types.h> #include <linux/kvm_host.h> +#include "timing.h" /* interrupt priortity ordering */ #define BOOKE_IRQPRIO_DATA_STORAGE 0 @@ -50,8 +51,10 @@ static inline void kvmppc_set_msr(struct vcpu->arch.msr = new_msr; - if (vcpu->arch.msr & MSR_WE) + if (vcpu->arch.msr & MSR_WE) { kvm_vcpu_block(vcpu); + kvmppc_set_exit_type(vcpu, EMULATED_MTMSRWE_EXITS); + }; } #endif /* __KVM_BOOKE_H__ */ diff --git a/arch/powerpc/kvm/booke_interrupts.S b/arch/powerpc/kvm/booke_interrupts.S --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -106,6 +106,18 @@ _GLOBAL(kvmppc_resume_host) li r6, 1 slw r6, r6, r5 + +#ifdef CONFIG_KVM_EXIT_TIMING + /* save exit time */ +1: + mfspr r7, SPRN_TBRU + mfspr r8, SPRN_TBRL + mfspr r9, SPRN_TBRU + cmpw r9, r7 + bne 1b + stw r8, VCPU_TIMING_EXIT_TBL(r4) + stw r9, VCPU_TIMING_EXIT_TBU(r4) +#endif /* Save the faulting instruction and all GPRs for emulation. */ andi. r7, r6, NEED_INST_MASK @@ -375,6 +387,18 @@ lightweight_exit: lwz r3, VCPU_SPRG7(r4) mtspr SPRN_SPRG7, r3 +#ifdef CONFIG_KVM_EXIT_TIMING + /* save enter time */ +1: + mfspr r6, SPRN_TBRU + mfspr r7, SPRN_TBRL + mfspr r8, SPRN_TBRU + cmpw r8, r6 + bne 1b + stw r7, VCPU_TIMING_LAST_ENTER_TBL(r4) + stw r8, VCPU_TIMING_LAST_ENTER_TBU(r4) +#endif + /* Finish loading guest volatiles and jump to guest. */ lwz r3, VCPU_CTR(r4) mtctr r3 diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -28,6 +28,7 @@ #include <asm/byteorder.h> #include <asm/kvm_ppc.h> #include <asm/disassemble.h> +#include "timing.h" void kvmppc_emulate_dec(struct kvm_vcpu *vcpu) { @@ -72,6 +73,9 @@ int kvmppc_emulate_instruction(struct kv int sprn; enum emulation_result emulated = EMULATE_DONE; int advance = 1; + + /* this default type might be overwritten by subcategories */ + kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS); switch (get_op(inst)) { case 3: /* trap */ diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -28,7 +28,7 @@ #include <asm/uaccess.h> #include <asm/kvm_ppc.h> #include <asm/tlbflush.h> - +#include "timing.h" gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn) { @@ -170,11 +170,15 @@ void kvm_arch_flush_shadow(struct kvm *k struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) { - return kvmppc_core_vcpu_create(kvm, id); + struct kvm_vcpu *vcpu; + vcpu = kvmppc_core_vcpu_create(kvm, id); + kvmppc_create_vcpu_debugfs(vcpu, id); + return vcpu; } void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) { + kvmppc_remove_vcpu_debugfs(vcpu); kvmppc_core_vcpu_free(vcpu); } diff --git a/arch/powerpc/kvm/timing.c b/arch/powerpc/kvm/timing.c new file mode 100644 --- /dev/null +++ b/arch/powerpc/kvm/timing.c @@ -0,0 +1,262 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * Copyright IBM Corp. 2007 + * + * Authors: Hollis Blanchard <hollisb@xxxxxxxxxx> + * Christian Ehrhardt <ehrhardt@xxxxxxxxxxxxxxxxxx> + */ + +#include <linux/kvm_host.h> +#include <linux/fs.h> +#include <linux/seq_file.h> +#include <linux/debugfs.h> +#include <linux/uaccess.h> + +#include "timing.h" +#include <asm/time.h> +#include <asm-generic/div64.h> + +void kvmppc_init_timing_stats(struct kvm_vcpu *vcpu) +{ + int i; + + /* pause guest execution to avoid concurrent updates */ + local_irq_disable(); + mutex_lock(&vcpu->mutex); + + vcpu->arch.last_exit_type = 0xDEAD; + for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) { + vcpu->arch.timing_count_type[i] = 0; + vcpu->arch.timing_max_duration[i] = 0; + vcpu->arch.timing_min_duration[i] = 0xFFFFFFFF; + vcpu->arch.timing_sum_duration[i] = 0; + vcpu->arch.timing_sum_quad_duration[i] = 0; + } + vcpu->arch.timing_last_exit = 0; + vcpu->arch.timing_exit.tv64 = 0; + vcpu->arch.timing_last_enter.tv64 = 0; + + mutex_unlock(&vcpu->mutex); + local_irq_enable(); +} + +static void add_exit_timing(struct kvm_vcpu *vcpu, + u64 duration, int type) +{ + u64 old; + + do_div(duration, tb_ticks_per_usec); + if (unlikely(duration > 0xFFFFFFFF)) { + printk(KERN_ERR"%s - duration too big -> overflow" + " duration %lld type %d exit #%d\n", + __func__, duration, type, + vcpu->arch.timing_count_type[type]); + return; + } + + vcpu->arch.timing_count_type[type]++; + + /* sum */ + old = vcpu->arch.timing_sum_duration[type]; + vcpu->arch.timing_sum_duration[type] += duration; + if (unlikely(old > vcpu->arch.timing_sum_duration[type])) { + printk(KERN_ERR"%s - wrap adding sum of durations" + " old %lld new %lld type %d exit # of type %d\n", + __func__, old, vcpu->arch.timing_sum_duration[type], + type, vcpu->arch.timing_count_type[type]); + } + + /* square sum */ + old = vcpu->arch.timing_sum_quad_duration[type]; + vcpu->arch.timing_sum_quad_duration[type] += (duration*duration); + if (unlikely(old > vcpu->arch.timing_sum_quad_duration[type])) { + printk(KERN_ERR"%s - wrap adding sum of squared durations" + " old %lld new %lld type %d exit # of type %d\n", + __func__, old, + vcpu->arch.timing_sum_quad_duration[type], + type, vcpu->arch.timing_count_type[type]); + } + + /* set min/max */ + if (unlikely(duration < vcpu->arch.timing_min_duration[type])) + vcpu->arch.timing_min_duration[type] = duration; + if (unlikely(duration > vcpu->arch.timing_max_duration[type])) + vcpu->arch.timing_max_duration[type] = duration; +} + +void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu) +{ + u64 exit = vcpu->arch.timing_last_exit; + u64 enter = vcpu->arch.timing_last_enter.tv64; + + /* save exit time, used next exit when the reenter time is known */ + vcpu->arch.timing_last_exit = vcpu->arch.timing_exit.tv64; + + if (unlikely(vcpu->arch.last_exit_type == 0xDEAD || exit == 0)) + return; /* skip incomplete cycle (e.g. after reset) */ + + /* update statistics for average and standard deviation */ + add_exit_timing(vcpu, (enter - exit), vcpu->arch.last_exit_type); + /* enter -> timing_last_exit is time spent in guest - log this too */ + add_exit_timing(vcpu, (vcpu->arch.timing_last_exit - enter), + TIMEINGUEST); +} + +static const char *kvm_exit_names[__NUMBER_OF_KVM_EXIT_TYPES] = { + [MMIO_EXITS] = "MMIO", + [DCR_EXITS] = "DCR", + [SIGNAL_EXITS] = "SIGNAL", + [ITLB_REAL_MISS_EXITS] = "ITLBREAL", + [ITLB_VIRT_MISS_EXITS] = "ITLBVIRT", + [DTLB_REAL_MISS_EXITS] = "DTLBREAL", + [DTLB_VIRT_MISS_EXITS] = "DTLBVIRT", + [SYSCALL_EXITS] = "SYSCALL", + [ISI_EXITS] = "ISI", + [DSI_EXITS] = "DSI", + [EMULATED_INST_EXITS] = "EMULINST", + [EMULATED_MTMSRWE_EXITS] = "EMUL_WAIT", + [EMULATED_WRTEE_EXITS] = "EMUL_WRTEE", + [EMULATED_MTSPR_EXITS] = "EMUL_MTSPR", + [EMULATED_MFSPR_EXITS] = "EMUL_MFSPR", + [EMULATED_MTMSR_EXITS] = "EMUL_MTMSR", + [EMULATED_MFMSR_EXITS] = "EMUL_MFMSR", + [EMULATED_TLBSX_EXITS] = "EMUL_TLBSX", + [EMULATED_TLBWE_EXITS] = "EMUL_TLBWE", + [EMULATED_RFI_EXITS] = "EMUL_RFI", + [DEC_EXITS] = "DEC", + [EXT_INTR_EXITS] = "EXTINT", + [HALT_WAKEUP] = "HALT", + [USR_PR_INST] = "USR_PR_INST", + [FP_UNAVAIL] = "FP_UNAVAIL", + [DEBUG_EXITS] = "DEBUG", + [TIMEINGUEST] = "TIMEINGUEST" +}; + +static int kvmppc_exit_timing_show(struct seq_file *m, void *private) +{ + struct kvm_vcpu *vcpu = m->private; + int i; + u64 min, max; + + for (i = 0; i < __NUMBER_OF_KVM_EXIT_TYPES; i++) { + if (vcpu->arch.timing_min_duration[i] == 0xFFFFFFFF) + min = 0; + else + min = vcpu->arch.timing_min_duration[i]; + if (vcpu->arch.timing_max_duration[i] == 0) + max = 0; + else + max = vcpu->arch.timing_max_duration[i]; + + seq_printf(m, "%12s: count %10d min %10lld " + "max %10lld sum %20lld sum_quad %20lld\n", + kvm_exit_names[i], vcpu->arch.timing_count_type[i], + vcpu->arch.timing_min_duration[i], + vcpu->arch.timing_max_duration[i], + vcpu->arch.timing_sum_duration[i], + vcpu->arch.timing_sum_quad_duration[i]); + } + return 0; +} + +static ssize_t kvmppc_exit_timing_write(struct file *file, + const char __user *user_buf, + size_t count, loff_t *ppos) +{ + size_t len; + int err; + const char __user *p; + char c; + + len = 0; + p = user_buf; + while (len < count) { + if (get_user(c, p++)) + err = -EFAULT; + if (c == 0 || c == '\n') + break; + len++; + } + + if (len > 1) { + err = -EINVAL; + goto done; + } + + if (copy_from_user(&c, user_buf, sizeof(c))) { + err = -EFAULT; + goto done; + } + + if (c == 'c') { + struct seq_file *seqf = (struct seq_file *)file->private_data; + struct kvm_vcpu *vcpu = seqf->private; + /* write does not affect out buffers previsously generated with + * show. Seq file is locked here to prevent races of init with + * a show call */ + mutex_lock(&seqf->lock); + kvmppc_init_timing_stats(vcpu); + mutex_unlock(&seqf->lock); + err = count; + } else { + err = -EINVAL; + goto done; + } + +done: + return err; +} + +static int kvmppc_exit_timing_open(struct inode *inode, struct file *file) +{ + return single_open(file, kvmppc_exit_timing_show, inode->i_private); +} + +static struct file_operations kvmppc_exit_timing_fops = { + .owner = THIS_MODULE, + .open = kvmppc_exit_timing_open, + .read = seq_read, + .write = kvmppc_exit_timing_write, + .llseek = seq_lseek, + .release = single_release, +}; + +void kvmppc_create_vcpu_debugfs(struct kvm_vcpu *vcpu, unsigned int id) +{ + static char dbg_fname[50]; + struct dentry *debugfs_file; + + snprintf(dbg_fname, sizeof(dbg_fname), "vm%u_vcpu%03u_timing", + current->pid, id); + debugfs_file = debugfs_create_file(dbg_fname, 0666, + kvm_debugfs_dir, vcpu, + &kvmppc_exit_timing_fops); + + if (!debugfs_file) { + printk(KERN_ERR"%s: error creating debugfs file %s\n", + __func__, dbg_fname); + return; + } + + vcpu->arch.debugfs_exit_timing = debugfs_file; +} + +void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu *vcpu) +{ + if (vcpu->arch.debugfs_exit_timing) { + debugfs_remove(vcpu->arch.debugfs_exit_timing); + vcpu->arch.debugfs_exit_timing = NULL; + } +} diff --git a/arch/powerpc/kvm/timing.h b/arch/powerpc/kvm/timing.h new file mode 100644 --- /dev/null +++ b/arch/powerpc/kvm/timing.h @@ -0,0 +1,102 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * Copyright IBM Corp. 2008 + * + * Authors: Christian Ehrhardt <ehrhardt@xxxxxxxxxxxxxxxxxx> + */ + +#ifndef __POWERPC_KVM_EXITTIMING_H__ +#define __POWERPC_KVM_EXITTIMING_H__ + +#include <linux/kvm_host.h> +#include <asm/kvm_host.h> + +#ifdef CONFIG_KVM_EXIT_TIMING +void kvmppc_init_timing_stats(struct kvm_vcpu *vcpu); +void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu); +void kvmppc_create_vcpu_debugfs(struct kvm_vcpu *vcpu, unsigned int id); +void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu *vcpu); + +static inline void kvmppc_set_exit_type(struct kvm_vcpu *vcpu, int type) +{ + vcpu->arch.last_exit_type = type; +} + +#else +/* if exit timing is not configured there is no need to build the c file */ +static inline void kvmppc_init_timing_stats(struct kvm_vcpu *vcpu) {} +static inline void kvmppc_update_timing_stats(struct kvm_vcpu *vcpu) {} +static inline void kvmppc_create_vcpu_debugfs(struct kvm_vcpu *vcpu, + unsigned int id) {} +static inline void kvmppc_remove_vcpu_debugfs(struct kvm_vcpu *vcpu) {} +static inline void kvmppc_set_exit_type(struct kvm_vcpu *vcpu, int type) {} +#endif /* CONFIG_KVM_EXIT_TIMING */ + +/* account the exit in kvm_stats */ +static inline void account_exit_stat(struct kvm_vcpu *vcpu, int type) +{ + /* type has to be known at build time for optimization */ + BUILD_BUG_ON(__builtin_constant_p(type)); + switch (type) { + case EXT_INTR_EXITS: + vcpu->stat.ext_intr_exits++; + break; + case DEC_EXITS: + vcpu->stat.dec_exits++; + break; + case EMULATED_INST_EXITS: + vcpu->stat.emulated_inst_exits++; + break; + case DCR_EXITS: + vcpu->stat.dcr_exits++; + break; + case DSI_EXITS: + vcpu->stat.dsi_exits++; + break; + case ISI_EXITS: + vcpu->stat.isi_exits++; + break; + case SYSCALL_EXITS: + vcpu->stat.syscall_exits++; + break; + case DTLB_REAL_MISS_EXITS: + vcpu->stat.dtlb_real_miss_exits++; + break; + case DTLB_VIRT_MISS_EXITS: + vcpu->stat.dtlb_virt_miss_exits++; + break; + case MMIO_EXITS: + vcpu->stat.mmio_exits++; + break; + case ITLB_REAL_MISS_EXITS: + vcpu->stat.itlb_real_miss_exits++; + break; + case ITLB_VIRT_MISS_EXITS: + vcpu->stat.itlb_virt_miss_exits++; + break; + case SIGNAL_EXITS: + vcpu->stat.signal_exits++; + break; + } +} + +/* wrapper to set exit time and account for it in kvm_stats */ +static inline void account_exit(struct kvm_vcpu *vcpu, int type) +{ + kvmppc_set_exit_type(vcpu, type); + account_exit_stat(vcpu, type); +} + +#endif /* __POWERPC_KVM_EXITTIMING_H__ */ -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
