| Message ID | 1500896403-25663-1-git-send-email-imbrenda@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 24/07/2017 13:40, Claudio Imbrenda wrote: > Simplify and improve the code so that the PID is always available in > the uevent even when debugfs is not available. > > This adds a userspace_pid field to struct kvm, as per Radim's > suggestion, so that the PID can be retrieved on destruction too. > > Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com> > Fixes: 286de8f6ac9202 ("KVM: trigger uevents when creating or destroying a VM") > Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com> > --- > include/linux/kvm_host.h | 1 + > virt/kvm/kvm_main.c | 35 ++++++++++++----------------------- > 2 files changed, 13 insertions(+), 23 deletions(-) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 648b34c..890b706 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -445,6 +445,7 @@ struct kvm { > struct kvm_stat_data **debugfs_stat_data; > struct srcu_struct srcu; > struct srcu_struct irq_srcu; > + pid_t userspace_pid; > }; > > #define kvm_err(fmt, ...) \ > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 82987d4..f3f7427 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -3883,7 +3883,6 @@ static const struct file_operations *stat_fops[] = { > static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm) > { > struct kobj_uevent_env *env; > - char *tmp, *pathbuf = NULL; > unsigned long long created, active; > > if (!kvm_dev.this_device || !kvm) > @@ -3907,38 +3906,28 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm) > add_uevent_var(env, "CREATED=%llu", created); > add_uevent_var(env, "COUNT=%llu", active); > > - if (type == KVM_EVENT_CREATE_VM) > + if (type == KVM_EVENT_CREATE_VM) { > add_uevent_var(env, "EVENT=create"); > - else if (type == KVM_EVENT_DESTROY_VM) > + kvm->userspace_pid = task_pid_nr(current); > + } else if (type == KVM_EVENT_DESTROY_VM) { > add_uevent_var(env, "EVENT=destroy"); > + } > + add_uevent_var(env, "PID=%d", kvm->userspace_pid); > > if (kvm->debugfs_dentry) { > - char p[ITOA_MAX_LEN]; > - > - snprintf(p, sizeof(p), "%s", kvm->debugfs_dentry->d_name.name); > - tmp = strchrnul(p + 1, '-'); > - *tmp = '\0'; > - add_uevent_var(env, "PID=%s", p); > - pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); > - if (pathbuf) { > - /* sizeof counts the final '\0' */ > - int len = sizeof("STATS_PATH=") - 1; > - const char *pvar = "STATS_PATH="; > - > - tmp = dentry_path_raw(kvm->debugfs_dentry, > - pathbuf + len, > - PATH_MAX - len); > - if (!IS_ERR(tmp)) { > - memcpy(tmp - len, pvar, len); > - env->envp[env->envp_idx++] = tmp - len; > - } > + char *tmp, *p = kmalloc(PATH_MAX, GFP_KERNEL); > + > + if (p) { > + tmp = dentry_path_raw(kvm->debugfs_dentry, p, PATH_MAX); > + if (!IS_ERR(tmp)) > + add_uevent_var(env, "STATS_PATH=%s", tmp); > + kfree(p); > } > } > /* no need for checks, since we are adding at most only 5 keys */ > env->envp[env->envp_idx++] = NULL; > kobject_uevent_env(&kvm_dev.this_device->kobj, KOBJ_CHANGE, env->envp); > kfree(env); > - kfree(pathbuf); > } > > static int kvm_init_debug(void) > Looks good, thanks. Paolo
On 24.07.2017 13:40, Claudio Imbrenda wrote: > Simplify and improve the code so that the PID is always available in > the uevent even when debugfs is not available. > > This adds a userspace_pid field to struct kvm, as per Radim's > suggestion, so that the PID can be retrieved on destruction too. > > Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com> > Fixes: 286de8f6ac9202 ("KVM: trigger uevents when creating or destroying a VM") > Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com> > --- > include/linux/kvm_host.h | 1 + > virt/kvm/kvm_main.c | 35 ++++++++++++----------------------- > 2 files changed, 13 insertions(+), 23 deletions(-) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 648b34c..890b706 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -445,6 +445,7 @@ struct kvm { > struct kvm_stat_data **debugfs_stat_data; > struct srcu_struct srcu; > struct srcu_struct irq_srcu; > + pid_t userspace_pid; > }; > > #define kvm_err(fmt, ...) \ > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 82987d4..f3f7427 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -3883,7 +3883,6 @@ static const struct file_operations *stat_fops[] = { > static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm) > { > struct kobj_uevent_env *env; > - char *tmp, *pathbuf = NULL; > unsigned long long created, active; > > if (!kvm_dev.this_device || !kvm) > @@ -3907,38 +3906,28 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm) > add_uevent_var(env, "CREATED=%llu", created); > add_uevent_var(env, "COUNT=%llu", active); > > - if (type == KVM_EVENT_CREATE_VM) > + if (type == KVM_EVENT_CREATE_VM) { > add_uevent_var(env, "EVENT=create"); > - else if (type == KVM_EVENT_DESTROY_VM) > + kvm->userspace_pid = task_pid_nr(current); > + } else if (type == KVM_EVENT_DESTROY_VM) { > add_uevent_var(env, "EVENT=destroy"); > + } > + add_uevent_var(env, "PID=%d", kvm->userspace_pid); > > if (kvm->debugfs_dentry) { > - char p[ITOA_MAX_LEN]; > - > - snprintf(p, sizeof(p), "%s", kvm->debugfs_dentry->d_name.name); > - tmp = strchrnul(p + 1, '-'); > - *tmp = '\0'; > - add_uevent_var(env, "PID=%s", p); > - pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); > - if (pathbuf) { > - /* sizeof counts the final '\0' */ > - int len = sizeof("STATS_PATH=") - 1; > - const char *pvar = "STATS_PATH="; > - > - tmp = dentry_path_raw(kvm->debugfs_dentry, > - pathbuf + len, > - PATH_MAX - len); > - if (!IS_ERR(tmp)) { > - memcpy(tmp - len, pvar, len); > - env->envp[env->envp_idx++] = tmp - len; > - } > + char *tmp, *p = kmalloc(PATH_MAX, GFP_KERNEL); > + > + if (p) { > + tmp = dentry_path_raw(kvm->debugfs_dentry, p, PATH_MAX); > + if (!IS_ERR(tmp)) > + add_uevent_var(env, "STATS_PATH=%s", tmp); > + kfree(p); > } > } > /* no need for checks, since we are adding at most only 5 keys */ > env->envp[env->envp_idx++] = NULL; > kobject_uevent_env(&kvm_dev.this_device->kobj, KOBJ_CHANGE, env->envp); > kfree(env); > - kfree(pathbuf); > } > > static int kvm_init_debug(void) > Yes, much better! Reviewed-by: David Hildenbrand <david@redhat.com>
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 648b34c..890b706 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -445,6 +445,7 @@ struct kvm { struct kvm_stat_data **debugfs_stat_data; struct srcu_struct srcu; struct srcu_struct irq_srcu; + pid_t userspace_pid; }; #define kvm_err(fmt, ...) \ diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 82987d4..f3f7427 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3883,7 +3883,6 @@ static const struct file_operations *stat_fops[] = { static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm) { struct kobj_uevent_env *env; - char *tmp, *pathbuf = NULL; unsigned long long created, active; if (!kvm_dev.this_device || !kvm) @@ -3907,38 +3906,28 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm) add_uevent_var(env, "CREATED=%llu", created); add_uevent_var(env, "COUNT=%llu", active); - if (type == KVM_EVENT_CREATE_VM) + if (type == KVM_EVENT_CREATE_VM) { add_uevent_var(env, "EVENT=create"); - else if (type == KVM_EVENT_DESTROY_VM) + kvm->userspace_pid = task_pid_nr(current); + } else if (type == KVM_EVENT_DESTROY_VM) { add_uevent_var(env, "EVENT=destroy"); + } + add_uevent_var(env, "PID=%d", kvm->userspace_pid); if (kvm->debugfs_dentry) { - char p[ITOA_MAX_LEN]; - - snprintf(p, sizeof(p), "%s", kvm->debugfs_dentry->d_name.name); - tmp = strchrnul(p + 1, '-'); - *tmp = '\0'; - add_uevent_var(env, "PID=%s", p); - pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); - if (pathbuf) { - /* sizeof counts the final '\0' */ - int len = sizeof("STATS_PATH=") - 1; - const char *pvar = "STATS_PATH="; - - tmp = dentry_path_raw(kvm->debugfs_dentry, - pathbuf + len, - PATH_MAX - len); - if (!IS_ERR(tmp)) { - memcpy(tmp - len, pvar, len); - env->envp[env->envp_idx++] = tmp - len; - } + char *tmp, *p = kmalloc(PATH_MAX, GFP_KERNEL); + + if (p) { + tmp = dentry_path_raw(kvm->debugfs_dentry, p, PATH_MAX); + if (!IS_ERR(tmp)) + add_uevent_var(env, "STATS_PATH=%s", tmp); + kfree(p); } } /* no need for checks, since we are adding at most only 5 keys */ env->envp[env->envp_idx++] = NULL; kobject_uevent_env(&kvm_dev.this_device->kobj, KOBJ_CHANGE, env->envp); kfree(env); - kfree(pathbuf); } static int kvm_init_debug(void)