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>
This commit is contained in:
Hollis Blanchard 2008-12-02 15:51:57 -06:00 committed by Avi Kivity
parent c5fbdffbda
commit 73e75b416f
13 changed files with 516 additions and 18 deletions

View file

@ -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;

View file

@ -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;
}

View file

@ -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;
}

View file

@ -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;
}

View file

@ -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

View file

@ -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)

View file

@ -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);
}

View file

@ -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__ */

View file

@ -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

View file

@ -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;

View file

@ -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);
}

262
arch/powerpc/kvm/timing.c Normal file
View file

@ -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;
}
}

102
arch/powerpc/kvm/timing.h Normal file
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@ -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__ */