diff options
author | Luiz Capitulino <lcapitulino@redhat.com> | 2016-09-16 10:27:35 -0400 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-09-16 16:57:47 +0200 |
commit | 45b5939e50746b92fd4cb47c02524f79ba8fabe6 (patch) | |
tree | 2913b6e168819a11ff761d4d5106f89e1c5ae224 | |
parent | 235539b48a2357da28f52d66d04bec04f3dcb9dd (diff) |
kvm: create per-vcpu dirs in debugfs
This commit adds the ability for archs to export
per-vcpu information via a new per-vcpu dir in
the VM's debugfs directory.
If kvm_arch_has_vcpu_debugfs() returns true, then KVM
will create a vcpu dir for each vCPU in the VM's
debugfs directory. Then kvm_arch_create_vcpu_debugfs()
is responsible for populating each vcpu directory
with arch specific entries.
The per-vcpu path in debugfs will look like:
/sys/kernel/debug/kvm/29162-10/vcpu0
/sys/kernel/debug/kvm/29162-10/vcpu1
This is all arch specific for now because the only
user of this interface (x86) wants to export x86-specific
per-vcpu information to user-space.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-rw-r--r-- | include/linux/kvm_host.h | 1 | ||||
-rw-r--r-- | virt/kvm/kvm_main.c | 32 |
2 files changed, 33 insertions, 0 deletions
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 5486ff9aa71e..01c0b9cc3915 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -265,6 +265,7 @@ struct kvm_vcpu { #endif bool preempted; struct kvm_vcpu_arch arch; + struct dentry *debugfs_dentry; }; static inline int kvm_vcpu_exiting_guest_mode(struct kvm_vcpu *vcpu) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a6e864c67e35..81dfc73d3df3 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2371,6 +2371,7 @@ static int kvm_vcpu_release(struct inode *inode, struct file *filp) { struct kvm_vcpu *vcpu = filp->private_data; + debugfs_remove_recursive(vcpu->debugfs_dentry); kvm_put_kvm(vcpu->kvm); return 0; } @@ -2393,6 +2394,32 @@ static int create_vcpu_fd(struct kvm_vcpu *vcpu) return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC); } +static int kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu) +{ + char dir_name[ITOA_MAX_LEN * 2]; + int ret; + + if (!kvm_arch_has_vcpu_debugfs()) + return 0; + + if (!debugfs_initialized()) + return 0; + + snprintf(dir_name, sizeof(dir_name), "vcpu%d", vcpu->vcpu_id); + vcpu->debugfs_dentry = debugfs_create_dir(dir_name, + vcpu->kvm->debugfs_dentry); + if (!vcpu->debugfs_dentry) + return -ENOMEM; + + ret = kvm_arch_create_vcpu_debugfs(vcpu); + if (ret < 0) { + debugfs_remove_recursive(vcpu->debugfs_dentry); + return ret; + } + + return 0; +} + /* * Creates some virtual cpus. Good luck creating more than one. */ @@ -2425,6 +2452,10 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id) if (r) goto vcpu_destroy; + r = kvm_create_vcpu_debugfs(vcpu); + if (r) + goto vcpu_destroy; + mutex_lock(&kvm->lock); if (kvm_get_vcpu_by_id(kvm, id)) { r = -EEXIST; @@ -2456,6 +2487,7 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id) unlock_vcpu_destroy: mutex_unlock(&kvm->lock); + debugfs_remove_recursive(vcpu->debugfs_dentry); vcpu_destroy: kvm_arch_vcpu_destroy(vcpu); vcpu_decrement: |