diff options
author | Hollis Blanchard <hollisb@us.ibm.com> | 2008-12-02 15:51:57 -0600 |
---|---|---|
committer | Avi Kivity <avi@redhat.com> | 2008-12-31 16:55:41 +0200 |
commit | 73e75b416ffcfa3a84952d8e389a0eca080f00e1 (patch) | |
tree | 6195be5b0fa56235550679f35ca990093dd081ca /arch | |
parent | c5fbdffbda79254047ec83b09c1a61a3655d052a (diff) |
KVM: ppc: Implement in-kernel exit timing statistics
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 much 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 simplified together with the exit timing statistic code (still
working with exit timing disabled in .config).
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/powerpc/include/asm/kvm_host.h | 56 | ||||
-rw-r--r-- | arch/powerpc/kernel/asm-offsets.c | 11 | ||||
-rw-r--r-- | arch/powerpc/kvm/44x_emulate.c | 11 | ||||
-rw-r--r-- | arch/powerpc/kvm/44x_tlb.c | 3 | ||||
-rw-r--r-- | arch/powerpc/kvm/Kconfig | 11 | ||||
-rw-r--r-- | arch/powerpc/kvm/Makefile | 1 | ||||
-rw-r--r-- | arch/powerpc/kvm/booke.c | 36 | ||||
-rw-r--r-- | arch/powerpc/kvm/booke.h | 5 | ||||
-rw-r--r-- | arch/powerpc/kvm/booke_interrupts.S | 24 | ||||
-rw-r--r-- | arch/powerpc/kvm/emulate.c | 4 | ||||
-rw-r--r-- | arch/powerpc/kvm/powerpc.c | 8 | ||||
-rw-r--r-- | arch/powerpc/kvm/timing.c | 262 | ||||
-rw-r--r-- | arch/powerpc/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 index a4a7d5ef6cf8..2f5b49f2a98e 100644 --- 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 index ba39526d3201..9937fe44555f 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -383,5 +383,16 @@ int main(void) DEFINE(PTE_T_LOG2, PTE_T_LOG2); #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 index 9ef79c78ede9..69f88d53c428 100644 --- 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_run *run, struct kvm_vcpu *vcpu, 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_run *run, struct kvm_vcpu *vcpu, 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_run *run, struct kvm_vcpu *vcpu, 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_run *run, struct kvm_vcpu *vcpu, 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_run *run, struct kvm_vcpu *vcpu, 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_vcpu *vcpu, int sprn, int rs) 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_vcpu *vcpu, int sprn, int rt) 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 index ff16d0e38433..9a34b8edb9e2 100644 --- 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" @@ -470,6 +471,7 @@ int kvmppc_44x_emul_tlbwe(struct kvm_vcpu *vcpu, u8 ra, u8 rs, u8 ws) 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; } @@ -493,5 +495,6 @@ int kvmppc_44x_emul_tlbsx(struct kvm_vcpu *vcpu, u8 rt, u8 ra, u8 rb, u8 rc) } 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 index e4ab1c7fd925..6dbdc4817d80 100644 --- 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 index f045fad0f4f1..df7ba59e6d53 100644 --- a/arch/powerpc/kvm/Makefile +++ b/arch/powerpc/kvm/Makefile @@ -9,6 +9,7 @@ common-objs-y = $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o) common-objs-$(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 index eb24383c87d2..0f171248e450 100644 --- 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 *run, struct kvm_vcpu *vcpu, 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 *run, struct kvm_vcpu *vcpu, 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 *run, struct kvm_vcpu *vcpu, /* 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 *run, struct kvm_vcpu *vcpu, 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 *run, struct kvm_vcpu *vcpu, 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 *run, struct kvm_vcpu *vcpu, 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 *run, struct kvm_vcpu *vcpu, 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 *run, struct kvm_vcpu *vcpu, * 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 *run, struct kvm_vcpu *vcpu, 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 *run, struct kvm_vcpu *vcpu, 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 *run, struct kvm_vcpu *vcpu, 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); } } @@ -418,6 +424,8 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) * 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 index 48d905fd60ab..cf7c94ca24bf 100644 --- 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 kvm_vcpu *vcpu, u32 new_msr) 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 index eb2186823e4e..084ebcd7dd83 100644 --- a/arch/powerpc/kvm/booke_interrupts.S +++ b/arch/powerpc/kvm/booke_interrupts.S @@ -107,6 +107,18 @@ _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 beq ..skip_inst_copy @@ -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 index 4c30fa0c31ea..d1d38daa93fb 100644 --- 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) { @@ -73,6 +74,9 @@ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu) 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 */ vcpu->arch.esr |= ESR_PTR; diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 7ad150e0fbbf..1deda37cb771 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -28,9 +28,9 @@ #include <asm/uaccess.h> #include <asm/kvm_ppc.h> #include <asm/tlbflush.h> +#include "timing.h" #include "../mm/mmu_decl.h" - gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn) { return gfn; @@ -171,11 +171,15 @@ void kvm_arch_flush_shadow(struct kvm *kvm) 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 index 000000000000..f42d2728a6a5 --- /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@us.ibm.com> + * Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> + */ + +#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 index 000000000000..1af7181fa2b5 --- /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@linux.vnet.ibm.com> + */ + +#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__ */ |