Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

KVM: ppc: Implement in-kernel exit timing statistics

Browse source 
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
Show stats Download patch file Download diff file Expand all files Collapse all files

56
arch/powerpc/include/asm/kvm_host.h
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;

11
arch/powerpc/kernel/asm-offsets.c
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;
}

11
arch/powerpc/kvm/44x_emulate.c
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;
}

3
arch/powerpc/kvm/44x_tlb.c
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;
}

11
arch/powerpc/kvm/Kconfig
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

1
arch/powerpc/kvm/Makefile
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)

36
arch/powerpc/kvm/booke.c
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);
}

5
arch/powerpc/kvm/booke.h
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__ */

24
arch/powerpc/kvm/booke_interrupts.S
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

4
arch/powerpc/kvm/emulate.c
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;

8
arch/powerpc/kvm/powerpc.c
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
View file

@ -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__ */