diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 08f8617f..64a02d4 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -1423,6 +1423,154 @@ static struct kvmppc_vcore *kvmppc_vcore_create(struct kvm *kvm, int core) return vcore; } +#ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING +static struct debugfs_timings_element { + const char *name; + size_t offset; +} timings[] = { + {"rm_entry", offsetof(struct kvm_vcpu, arch.rm_entry)}, + {"rm_intr", offsetof(struct kvm_vcpu, arch.rm_intr)}, + {"rm_exit", offsetof(struct kvm_vcpu, arch.rm_exit)}, + {"guest", offsetof(struct kvm_vcpu, arch.guest_time)}, + {"cede", offsetof(struct kvm_vcpu, arch.cede_time)}, +}; + +#define N_TIMINGS (sizeof(timings) / sizeof(timings[0])) + +struct debugfs_timings_state { + struct kvm_vcpu *vcpu; + unsigned int buflen; + char buf[N_TIMINGS * 100]; +}; + +static int debugfs_timings_open(struct inode *inode, struct file *file) +{ + struct kvm_vcpu *vcpu = inode->i_private; + struct debugfs_timings_state *p; + + p = kzalloc(sizeof(*p), GFP_KERNEL); + if (!p) + return -ENOMEM; + + kvm_get_kvm(vcpu->kvm); + p->vcpu = vcpu; + file->private_data = p; + + return nonseekable_open(inode, file); +} + +static int debugfs_timings_release(struct inode *inode, struct file *file) +{ + struct debugfs_timings_state *p = file->private_data; + + kvm_put_kvm(p->vcpu->kvm); + kfree(p); + return 0; +} + +static ssize_t debugfs_timings_read(struct file *file, char __user *buf, + size_t len, loff_t *ppos) +{ + struct debugfs_timings_state *p = file->private_data; + struct kvm_vcpu *vcpu = p->vcpu; + char *s, *buf_end; + struct kvmhv_tb_accumulator tb; + u64 count; + loff_t pos; + ssize_t n; + int i, loops; + bool ok; + + if (!p->buflen) { + s = p->buf; + buf_end = s + sizeof(p->buf); + for (i = 0; i < N_TIMINGS; ++i) { + struct kvmhv_tb_accumulator *acc; + + acc = (struct kvmhv_tb_accumulator *) + ((unsigned long)vcpu + timings[i].offset); + ok = false; + for (loops = 0; loops < 1000; ++loops) { + count = acc->seqcount; + if (!(count & 1)) { + smp_rmb(); + tb = *acc; + smp_rmb(); + if (count == acc->seqcount) { + ok = true; + break; + } + } + udelay(1); + } + if (!ok) + snprintf(s, buf_end - s, "%s: stuck\n", + timings[i].name); + else + snprintf(s, buf_end - s, + "%s: %llu %llu %llu %llu\n", + timings[i].name, count / 2, + tb_to_ns(tb.tb_total), + tb_to_ns(tb.tb_min), + tb_to_ns(tb.tb_max)); + s += strlen(s); + } + p->buflen = s - p->buf; + } + + pos = *ppos; + if (pos >= p->buflen) + return 0; + if (len > p->buflen - pos) + len = p->buflen - pos; + n = copy_to_user(buf, p->buf + pos, len); + if (n) { + if (n == len) + return -EFAULT; + len -= n; + } + *ppos = pos + len; + return len; +} + +static ssize_t debugfs_timings_write(struct file *file, const char __user *buf, + size_t len, loff_t *ppos) +{ + return -EACCES; +} + +static const struct file_operations debugfs_timings_ops = { + .owner = THIS_MODULE, + .open = debugfs_timings_open, + .release = debugfs_timings_release, + .read = debugfs_timings_read, + .write = debugfs_timings_write, + .llseek = generic_file_llseek, +}; + +/* Create a debugfs directory for the vcpu */ +static void debugfs_vcpu_init(struct kvm_vcpu *vcpu, unsigned int id) +{ + char buf[16]; + struct kvm *kvm = vcpu->kvm; + + snprintf(buf, sizeof(buf), "vcpu%u", id); + if (IS_ERR_OR_NULL(kvm->arch.debugfs_dir)) + return; + vcpu->arch.debugfs_dir = debugfs_create_dir(buf, kvm->arch.debugfs_dir); + if (IS_ERR_OR_NULL(vcpu->arch.debugfs_dir)) + return; + vcpu->arch.debugfs_timings = + debugfs_create_file("timings", 0444, vcpu->arch.debugfs_dir, + vcpu, &debugfs_timings_ops); +} + +#else /* CONFIG_KVM_BOOK3S_HV_EXIT_TIMING */ +static void debugfs_vcpu_init(struct kvm_vcpu *vcpu, unsigned int id) +{ +} +#endif /* CONFIG_KVM_BOOK3S_HV_EXIT_TIMING */ + static struct kvm_vcpu *kvmppc_core_vcpu_create_hv(struct kvm *kvm, unsigned int id) { @@ -1492,6 +1640,8 @@ static struct kvm_vcpu *kvmppc_core_vcpu_create_hv(struct kvm *kvm, vcpu->arch.cpu_type = KVM_CPU_3S_64; kvmppc_sanity_check(vcpu); + debugfs_vcpu_init(vcpu, id); + return vcpu; free_vcpu: |