[v2,2/6] KVM: stats: Support linear and logarithmic histogram statistics

Message ID	20210714223033.742261-3-jingzhangos@google.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <kvm-owner@kernel.org> Date: Wed, 14 Jul 2021 22:30:29 +0000 In-Reply-To: <20210714223033.742261-1-jingzhangos@google.com> Message-Id: <20210714223033.742261-3-jingzhangos@google.com> Mime-Version: 1.0 References: <20210714223033.742261-1-jingzhangos@google.com> Subject: [PATCH v2 2/6] KVM: stats: Support linear and logarithmic histogram statistics From: Jing Zhang <jingzhangos@google.com> To: KVM <kvm@vger.kernel.org>, KVMPPC <kvm-ppc@vger.kernel.org>, Paolo Bonzini <pbonzini@redhat.com>, Sean Christopherson <seanjc@google.com>, Jim Mattson <jmattson@google.com>, Peter Shier <pshier@google.com>, Oliver Upton <oupton@google.com>, David Rientjes <rientjes@google.com>, David Matlack <dmatlack@google.com> Cc: Jing Zhang <jingzhangos@google.com> Content-Type: text/plain; charset="UTF-8" Precedence: bulk
Series	Linear and Logarithmic histogram statistics \| expand [v2,0/6] Linear and Logarithmic histogram statistics [v2,1/6] KVM: stats: Add capability description for KVM binary stats [v2,2/6] KVM: stats: Support linear and logarithmic histogram statistics [v2,3/6] KVM: stats: Update doc for histogram statistics [v2,4/6] KVM: selftests: Add checks for histogram stats bucket_size field [v2,5/6] KVM: stats: Add halt_wait_ns stats for all architectures [v2,6/6] KVM: stats: Add halt polling related histogram stats

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]; +}

[v2,2/6] KVM: stats: Support linear and logarithmic histogram statistics

Commit Message

Patch