From e36de87d34a7f2f26b2e2129c6dc18a0024663eb Mon Sep 17 00:00:00 2001 From: Vineeth Pillai Date: Mon, 23 May 2022 15:03:27 -0400 Subject: KVM: debugfs: expose pid of vcpu threads Add a new debugfs file to expose the pid of each vcpu threads. This is very helpful for userland tools to get the vcpu pids without worrying about thread naming conventions of the VMM. Signed-off-by: Vineeth Pillai (Google) Message-Id: <20220523190327.2658-1-vineeth@bitbyteword.org> Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'virt') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 45188d11812c..da263c370d00 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3822,9 +3822,18 @@ static int create_vcpu_fd(struct kvm_vcpu *vcpu) return anon_inode_getfd(name, &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC); } +#ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS +static int vcpu_get_pid(void *data, u64 *val) +{ + struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data; + *val = pid_nr(rcu_access_pointer(vcpu->pid)); + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(vcpu_get_pid_fops, vcpu_get_pid, NULL, "%llu\n"); + static void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu) { -#ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS struct dentry *debugfs_dentry; char dir_name[ITOA_MAX_LEN * 2]; @@ -3834,10 +3843,12 @@ static void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu) snprintf(dir_name, sizeof(dir_name), "vcpu%d", vcpu->vcpu_id); debugfs_dentry = debugfs_create_dir(dir_name, vcpu->kvm->debugfs_dentry); + debugfs_create_file("pid", 0444, debugfs_dentry, vcpu, + &vcpu_get_pid_fops); kvm_arch_create_vcpu_debugfs(vcpu, debugfs_dentry); -#endif } +#endif /* * Creates some virtual cpus. Good luck creating more than one. -- cgit v1.2.1