[08/23] time: Use generic ns_common::count
diff mbox series

Message ID 159611040338.535980.6847379168016198580.stgit@localhost.localdomain
State New
Headers show
Series
  • proc: Introduce /proc/namespaces/ directory to expose namespaces lineary
Related show

Commit Message

Kirill Tkhai July 30, 2020, noon UTC
Convert time namespace to use generic counter.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
---
 include/linux/time_namespace.h |    9 ++++-----
 kernel/time/namespace.c        |    9 +++------
 2 files changed, 7 insertions(+), 11 deletions(-)

Comments

Christian Brauner July 30, 2020, 2:52 p.m. UTC | #1
On Thu, Jul 30, 2020 at 03:00:03PM +0300, Kirill Tkhai wrote:
> Convert time namespace to use generic counter.
> 
> Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
> ---

Looks good!
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>

>  include/linux/time_namespace.h |    9 ++++-----
>  kernel/time/namespace.c        |    9 +++------
>  2 files changed, 7 insertions(+), 11 deletions(-)
> 
> diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
> index 5b6031385db0..a51ffc089219 100644
> --- a/include/linux/time_namespace.h
> +++ b/include/linux/time_namespace.h
> @@ -4,7 +4,6 @@
>  
>  
>  #include <linux/sched.h>
> -#include <linux/kref.h>
>  #include <linux/nsproxy.h>
>  #include <linux/ns_common.h>
>  #include <linux/err.h>
> @@ -18,7 +17,6 @@ struct timens_offsets {
>  };
>  
>  struct time_namespace {
> -	struct kref		kref;
>  	struct user_namespace	*user_ns;
>  	struct ucounts		*ucounts;
>  	struct ns_common	ns;
> @@ -37,20 +35,21 @@ extern void timens_commit(struct task_struct *tsk, struct time_namespace *ns);
>  
>  static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
>  {
> -	kref_get(&ns->kref);
> +	refcount_inc(&ns->ns.count);
>  	return ns;
>  }
>  
>  struct time_namespace *copy_time_ns(unsigned long flags,
>  				    struct user_namespace *user_ns,
>  				    struct time_namespace *old_ns);
> -void free_time_ns(struct kref *kref);
> +void free_time_ns(struct time_namespace *ns);
>  int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
>  struct vdso_data *arch_get_vdso_data(void *vvar_page);
>  
>  static inline void put_time_ns(struct time_namespace *ns)
>  {
> -	kref_put(&ns->kref, free_time_ns);
> +	if (refcount_dec_and_test(&ns->ns.count))
> +		free_time_ns(ns);
>  }
>  
>  void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m);
> diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c
> index afc65e6be33e..c4c829eb3511 100644
> --- a/kernel/time/namespace.c
> +++ b/kernel/time/namespace.c
> @@ -92,7 +92,7 @@ static struct time_namespace *clone_time_ns(struct user_namespace *user_ns,
>  	if (!ns)
>  		goto fail_dec;
>  
> -	kref_init(&ns->kref);
> +	refcount_set(&ns->ns.count, 1);
>  
>  	ns->vvar_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
>  	if (!ns->vvar_page)
> @@ -226,11 +226,8 @@ static void timens_set_vvar_page(struct task_struct *task,
>  	mutex_unlock(&offset_lock);
>  }
>  
> -void free_time_ns(struct kref *kref)
> +void free_time_ns(struct time_namespace *ns)
>  {
> -	struct time_namespace *ns;
> -
> -	ns = container_of(kref, struct time_namespace, kref);
>  	dec_time_namespaces(ns->ucounts);
>  	put_user_ns(ns->user_ns);
>  	ns_free_inum(&ns->ns);
> @@ -464,7 +461,7 @@ const struct proc_ns_operations timens_for_children_operations = {
>  };
>  
>  struct time_namespace init_time_ns = {
> -	.kref		= KREF_INIT(3),
> +	.ns.count	= REFCOUNT_INIT(3),
>  	.user_ns	= &init_user_ns,
>  	.ns.inum	= PROC_TIME_INIT_INO,
>  	.ns.ops		= &timens_operations,
> 
>

Patch
diff mbox series

diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index 5b6031385db0..a51ffc089219 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -4,7 +4,6 @@ 
 
 
 #include <linux/sched.h>
-#include <linux/kref.h>
 #include <linux/nsproxy.h>
 #include <linux/ns_common.h>
 #include <linux/err.h>
@@ -18,7 +17,6 @@  struct timens_offsets {
 };
 
 struct time_namespace {
-	struct kref		kref;
 	struct user_namespace	*user_ns;
 	struct ucounts		*ucounts;
 	struct ns_common	ns;
@@ -37,20 +35,21 @@  extern void timens_commit(struct task_struct *tsk, struct time_namespace *ns);
 
 static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
 {
-	kref_get(&ns->kref);
+	refcount_inc(&ns->ns.count);
 	return ns;
 }
 
 struct time_namespace *copy_time_ns(unsigned long flags,
 				    struct user_namespace *user_ns,
 				    struct time_namespace *old_ns);
-void free_time_ns(struct kref *kref);
+void free_time_ns(struct time_namespace *ns);
 int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
 struct vdso_data *arch_get_vdso_data(void *vvar_page);
 
 static inline void put_time_ns(struct time_namespace *ns)
 {
-	kref_put(&ns->kref, free_time_ns);
+	if (refcount_dec_and_test(&ns->ns.count))
+		free_time_ns(ns);
 }
 
 void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m);
diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c
index afc65e6be33e..c4c829eb3511 100644
--- a/kernel/time/namespace.c
+++ b/kernel/time/namespace.c
@@ -92,7 +92,7 @@  static struct time_namespace *clone_time_ns(struct user_namespace *user_ns,
 	if (!ns)
 		goto fail_dec;
 
-	kref_init(&ns->kref);
+	refcount_set(&ns->ns.count, 1);
 
 	ns->vvar_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 	if (!ns->vvar_page)
@@ -226,11 +226,8 @@  static void timens_set_vvar_page(struct task_struct *task,
 	mutex_unlock(&offset_lock);
 }
 
-void free_time_ns(struct kref *kref)
+void free_time_ns(struct time_namespace *ns)
 {
-	struct time_namespace *ns;
-
-	ns = container_of(kref, struct time_namespace, kref);
 	dec_time_namespaces(ns->ucounts);
 	put_user_ns(ns->user_ns);
 	ns_free_inum(&ns->ns);
@@ -464,7 +461,7 @@  const struct proc_ns_operations timens_for_children_operations = {
 };
 
 struct time_namespace init_time_ns = {
-	.kref		= KREF_INIT(3),
+	.ns.count	= REFCOUNT_INIT(3),
 	.user_ns	= &init_user_ns,
 	.ns.inum	= PROC_TIME_INIT_INO,
 	.ns.ops		= &timens_operations,