Add new types of KVM stats, linear and logarithmic histogram.
Histogram are very useful for observing the value distribution
of time or size related stats.
Signed-off-by: Jing Zhang <jingzhangos@xxxxxxxxxx>
---
arch/arm64/kvm/guest.c | 4 ---
arch/mips/kvm/mips.c | 4 ---
arch/powerpc/kvm/book3s.c | 4 ---
arch/powerpc/kvm/booke.c | 4 ---
arch/s390/kvm/kvm-s390.c | 4 ---
arch/x86/kvm/x86.c | 4 ---
include/linux/kvm_host.h | 53 ++++++++++++++++++++++++++++-----------
include/linux/kvm_types.h | 15 +++++++++++
include/uapi/linux/kvm.h | 11 +++++---
virt/kvm/binary_stats.c | 32 +++++++++++++++++++++++
10 files changed, 92 insertions(+), 43 deletions(-)
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 1dfb83578277..5188184d25d0 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -31,8 +31,6 @@
const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
KVM_GENERIC_VM_STATS()
};
-static_assert(ARRAY_SIZE(kvm_vm_stats_desc) ==
- sizeof(struct kvm_vm_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vm_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
@@ -52,8 +50,6 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
STATS_DESC_COUNTER(VCPU, mmio_exit_kernel),
STATS_DESC_COUNTER(VCPU, exits)
};
-static_assert(ARRAY_SIZE(kvm_vcpu_stats_desc) ==
- sizeof(struct kvm_vcpu_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vcpu_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index af9dd029a4e1..75c6f264c626 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -41,8 +41,6 @@
const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
KVM_GENERIC_VM_STATS()
};
-static_assert(ARRAY_SIZE(kvm_vm_stats_desc) ==
- sizeof(struct kvm_vm_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vm_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
@@ -85,8 +83,6 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
STATS_DESC_COUNTER(VCPU, vz_cpucfg_exits),
#endif
};
-static_assert(ARRAY_SIZE(kvm_vcpu_stats_desc) ==
- sizeof(struct kvm_vcpu_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vcpu_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 79833f78d1da..5cc6e90095b0 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -43,8 +43,6 @@ const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
STATS_DESC_ICOUNTER(VM, num_2M_pages),
STATS_DESC_ICOUNTER(VM, num_1G_pages)
};
-static_assert(ARRAY_SIZE(kvm_vm_stats_desc) ==
- sizeof(struct kvm_vm_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vm_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
@@ -88,8 +86,6 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
STATS_DESC_COUNTER(VCPU, pthru_host),
STATS_DESC_COUNTER(VCPU, pthru_bad_aff)
};
-static_assert(ARRAY_SIZE(kvm_vcpu_stats_desc) ==
- sizeof(struct kvm_vcpu_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vcpu_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 551b30d84aee..5ed6c235e059 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -41,8 +41,6 @@ const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
STATS_DESC_ICOUNTER(VM, num_2M_pages),
STATS_DESC_ICOUNTER(VM, num_1G_pages)
};
-static_assert(ARRAY_SIZE(kvm_vm_stats_desc) ==
- sizeof(struct kvm_vm_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vm_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
@@ -79,8 +77,6 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
STATS_DESC_COUNTER(VCPU, pthru_host),
STATS_DESC_COUNTER(VCPU, pthru_bad_aff)
};
-static_assert(ARRAY_SIZE(kvm_vcpu_stats_desc) ==
- sizeof(struct kvm_vcpu_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vcpu_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index f9fb1e1d960d..c7f2b1124740 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -66,8 +66,6 @@ const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
STATS_DESC_COUNTER(VM, inject_service_signal),
STATS_DESC_COUNTER(VM, inject_virtio)
};
-static_assert(ARRAY_SIZE(kvm_vm_stats_desc) ==
- sizeof(struct kvm_vm_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vm_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
@@ -174,8 +172,6 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
STATS_DESC_COUNTER(VCPU, diagnose_other),
STATS_DESC_COUNTER(VCPU, pfault_sync)
};
-static_assert(ARRAY_SIZE(kvm_vcpu_stats_desc) ==
- sizeof(struct kvm_vcpu_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vcpu_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d715ae9f9108..e1b00597b84f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -236,8 +236,6 @@ const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
STATS_DESC_ICOUNTER(VM, nx_lpage_splits),
STATS_DESC_PCOUNTER(VM, max_mmu_page_hash_collisions)
};
-static_assert(ARRAY_SIZE(kvm_vm_stats_desc) ==
- sizeof(struct kvm_vm_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vm_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
@@ -277,8 +275,6 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
STATS_DESC_COUNTER(VCPU, directed_yield_successful),
STATS_DESC_ICOUNTER(VCPU, guest_mode)
};
-static_assert(ARRAY_SIZE(kvm_vcpu_stats_desc) ==
- sizeof(struct kvm_vcpu_stat) / sizeof(u64));
const struct kvm_stats_header kvm_vcpu_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index ae7735b490b4..c44cf5029e30 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1273,56 +1273,66 @@ struct _kvm_stats_desc {
char name[KVM_STATS_NAME_SIZE];
};
-#define STATS_DESC_COMMON(type, unit, base, exp) \
+#define STATS_DESC_COMMON(type, unit, base, exp, sz, bsz) \
.flags = type | unit | base | \
BUILD_BUG_ON_ZERO(type & ~KVM_STATS_TYPE_MASK) | \
BUILD_BUG_ON_ZERO(unit & ~KVM_STATS_UNIT_MASK) | \
BUILD_BUG_ON_ZERO(base & ~KVM_STATS_BASE_MASK), \
.exponent = exp, \
- .size = 1
+ .size = sz, \
+ .bucket_size = bsz
-#define VM_GENERIC_STATS_DESC(stat, type, unit, base, exp) \
+#define VM_GENERIC_STATS_DESC(stat, type, unit, base, exp, sz, bsz) \
{ \
{ \
- STATS_DESC_COMMON(type, unit, base, exp), \
+ STATS_DESC_COMMON(type, unit, base, exp, sz, bsz), \
.offset = offsetof(struct kvm_vm_stat, generic.stat) \
}, \
.name = #stat, \
}
-#define VCPU_GENERIC_STATS_DESC(stat, type, unit, base, exp) \
+#define VCPU_GENERIC_STATS_DESC(stat, type, unit, base, exp, sz, bsz) \
{ \
{ \
- STATS_DESC_COMMON(type, unit, base, exp), \
+ STATS_DESC_COMMON(type, unit, base, exp, sz, bsz), \
.offset = offsetof(struct kvm_vcpu_stat, generic.stat) \
}, \
.name = #stat, \
}
-#define VM_STATS_DESC(stat, type, unit, base, exp) \
+#define VM_STATS_DESC(stat, type, unit, base, exp, sz, bsz) \
{ \
{ \
- STATS_DESC_COMMON(type, unit, base, exp), \
+ STATS_DESC_COMMON(type, unit, base, exp, sz, bsz), \
.offset = offsetof(struct kvm_vm_stat, stat) \
}, \
.name = #stat, \
}
-#define VCPU_STATS_DESC(stat, type, unit, base, exp) \
+#define VCPU_STATS_DESC(stat, type, unit, base, exp, sz, bsz) \
{ \
{ \
- STATS_DESC_COMMON(type, unit, base, exp), \
+ STATS_DESC_COMMON(type, unit, base, exp, sz, bsz), \
.offset = offsetof(struct kvm_vcpu_stat, stat) \
}, \
.name = #stat, \
}
/* SCOPE: VM, VM_GENERIC, VCPU, VCPU_GENERIC */
-#define STATS_DESC(SCOPE, stat, type, unit, base, exp) \
- SCOPE##_STATS_DESC(stat, type, unit, base, exp)
+#define STATS_DESC(SCOPE, stat, type, unit, base, exp, sz, bsz) \
+ SCOPE##_STATS_DESC(stat, type, unit, base, exp, sz, bsz)
#define STATS_DESC_CUMULATIVE(SCOPE, name, unit, base, exponent) \
- STATS_DESC(SCOPE, name, KVM_STATS_TYPE_CUMULATIVE, unit, base, exponent)
+ STATS_DESC(SCOPE, name, KVM_STATS_TYPE_CUMULATIVE, \
+ unit, base, exponent, 1, 0)
#define STATS_DESC_INSTANT(SCOPE, name, unit, base, exponent) \
- STATS_DESC(SCOPE, name, KVM_STATS_TYPE_INSTANT, unit, base, exponent)
+ STATS_DESC(SCOPE, name, KVM_STATS_TYPE_INSTANT, \
+ unit, base, exponent, 1, 0)
#define STATS_DESC_PEAK(SCOPE, name, unit, base, exponent) \
- STATS_DESC(SCOPE, name, KVM_STATS_TYPE_PEAK, unit, base, exponent)
+ STATS_DESC(SCOPE, name, KVM_STATS_TYPE_PEAK, \
+ unit, base, exponent, 1, 0)
+#define STATS_DESC_LINEAR_HIST(SCOPE, name, unit, base, exponent, sz, bsz) \
+ STATS_DESC(SCOPE, name, KVM_STATS_TYPE_LINEAR_HIST, \
+ unit, base, exponent, sz, bsz)
+#define STATS_DESC_LOG_HIST(SCOPE, name, unit, base, exponent, sz) \
+ STATS_DESC(SCOPE, name, KVM_STATS_TYPE_LOG_HIST, \
+ unit, base, exponent, sz, 0)
/* Cumulative counter, read/write */
#define STATS_DESC_COUNTER(SCOPE, name) \
@@ -1341,6 +1351,14 @@ struct _kvm_stats_desc {
#define STATS_DESC_TIME_NSEC(SCOPE, name) \
STATS_DESC_CUMULATIVE(SCOPE, name, KVM_STATS_UNIT_SECONDS, \
KVM_STATS_BASE_POW10, -9)
+/* Linear histogram for time in nanosecond */
+#define STATS_DESC_LINHIST_TIME_NSEC(SCOPE, name, sz, bsz) \
+ STATS_DESC_LINEAR_HIST(SCOPE, name, KVM_STATS_UNIT_SECONDS, \
+ KVM_STATS_BASE_POW10, -9, sz, bsz)
+/* Logarithmic histogram for time in nanosecond */
+#define STATS_DESC_LOGHIST_TIME_NSEC(SCOPE, name, sz) \
+ STATS_DESC_LOG_HIST(SCOPE, name, KVM_STATS_UNIT_SECONDS, \
+ KVM_STATS_BASE_POW10, -9, sz)
#define KVM_GENERIC_VM_STATS() \
STATS_DESC_COUNTER(VM_GENERIC, remote_tlb_flush)
@@ -1354,10 +1372,15 @@ struct _kvm_stats_desc {
STATS_DESC_TIME_NSEC(VCPU_GENERIC, halt_poll_fail_ns)
extern struct dentry *kvm_debugfs_dir;
+
ssize_t kvm_stats_read(char *id, const struct kvm_stats_header *header,
const struct _kvm_stats_desc *desc,
void *stats, size_t size_stats,
char __user *user_buffer, size_t size, loff_t *offset);
+void kvm_stats_linear_hist_update(u64 *data, size_t size,
+ u64 value, size_t bucket_size);
+void kvm_stats_log_hist_update(u64 *data, size_t size, u64 value);
+
extern const struct kvm_stats_header kvm_vm_stats_header;
extern const struct _kvm_stats_desc kvm_vm_stats_desc[];
extern const struct kvm_stats_header kvm_vcpu_stats_header;
diff --git a/include/linux/kvm_types.h b/include/linux/kvm_types.h
index ed6a985c5680..723f8a77a8ea 100644
--- a/include/linux/kvm_types.h
+++ b/include/linux/kvm_types.h
@@ -76,6 +76,21 @@ struct kvm_mmu_memory_cache {
};
#endif
+/* Constants used for histogram stats */
+#define LINHIST_SIZE_SMALL 10
+#define LINHIST_SIZE_MEDIUM 20
+#define LINHIST_SIZE_LARGE 50
+#define LINHIST_SIZE_XLARGE 100
+#define LINHIST_BUCKET_SIZE_SMALL 10
+#define LINHIST_BUCKET_SIZE_MEDIUM 100
+#define LINHIST_BUCKET_SIZE_LARGE 1000
+#define LINHIST_BUCKET_SIZE_XLARGE 10000
+
+#define LOGHIST_BUCKET_COUNT_SMALL 8
+#define LOGHIST_BUCKET_COUNT_MEDIUM 16
+#define LOGHIST_BUCKET_COUNT_LARGE 32
+#define LOGHIST_BUCKET_COUNT_XLARGE 64
+
struct kvm_vm_stat_generic {
u64 remote_tlb_flush;
};
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index d9e4aabcb31a..a067410ebea5 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1965,7 +1965,9 @@ struct kvm_stats_header {
#define KVM_STATS_TYPE_CUMULATIVE (0x0 << KVM_STATS_TYPE_SHIFT)
#define KVM_STATS_TYPE_INSTANT (0x1 << KVM_STATS_TYPE_SHIFT)
#define KVM_STATS_TYPE_PEAK (0x2 << KVM_STATS_TYPE_SHIFT)
-#define KVM_STATS_TYPE_MAX KVM_STATS_TYPE_PEAK
+#define KVM_STATS_TYPE_LINEAR_HIST (0x3 << KVM_STATS_TYPE_SHIFT)
+#define KVM_STATS_TYPE_LOG_HIST (0x4 << KVM_STATS_TYPE_SHIFT)
+#define KVM_STATS_TYPE_MAX KVM_STATS_TYPE_LOG_HIST
#define KVM_STATS_UNIT_SHIFT 4
#define KVM_STATS_UNIT_MASK (0xF << KVM_STATS_UNIT_SHIFT)
@@ -1988,8 +1990,9 @@ struct kvm_stats_header {
* @size: The number of data items for this stats.
* Every data item is of type __u64.
* @offset: The offset of the stats to the start of stat structure in
- * struture kvm or kvm_vcpu.
- * @unused: Unused field for future usage. Always 0 for now.
+ * structure kvm or kvm_vcpu.
+ * @bucket_size: A parameter value used for histogram stats. It is only used
+ * for linear histogram stats, specifying the size of the bucket;
* @name: The name string for the stats. Its size is indicated by the
* &kvm_stats_header->name_size.
*/
@@ -1998,7 +2001,7 @@ struct kvm_stats_desc {
__s16 exponent;
__u16 size;
__u32 offset;
- __u32 unused;
+ __u32 bucket_size;
char name[];
};
diff --git a/virt/kvm/binary_stats.c b/virt/kvm/binary_stats.c
index e609d428811a..c134383f43a8 100644
--- a/virt/kvm/binary_stats.c
+++ b/virt/kvm/binary_stats.c
@@ -144,3 +144,35 @@ ssize_t kvm_stats_read(char *id, const struct kvm_stats_header *header,
*offset = pos;
return len;
}
+
+/**
+ * kvm_stats_linear_hist_update() - Update bucket value for linear histogram
+ * statistics data.
+ *
+ * @data: start address of the stats data
+ * @size: the number of bucket of the stats data
+ * @value: the new value used to update the linear histogram's bucket
+ * @bucket_size: the size (width) of a bucket
+ */
+void kvm_stats_linear_hist_update(u64 *data, size_t size,
+ u64 value, size_t bucket_size)
+{
+ size_t index = min((size_t)div64_u64(value, bucket_size), size - 1);
+
+ ++data[index];
+}
+
+/**
+ * kvm_stats_log_hist_update() - Update bucket value for logarithmic histogram
+ * statistics data.
+ *
+ * @data: start address of the stats data
+ * @size: the number of bucket of the stats data
+ * @value: the new value used to update the logarithmic histogram's bucket
+ */
+void kvm_stats_log_hist_update(u64 *data, size_t size, u64 value)
+{
+ size_t index = min((size_t)fls64(value), size - 1);
+
+ ++data[index];
+}
--
2.32.0.402.g57bb445576-goog
