percpu_ref: minor code and comment updates

* Some comments became stale.  Updated.
* percpu_ref_tryget() unnecessarily initializes @ret.  Removed.
* A blank line removed from percpu_ref_kill_rcu().
* Explicit function name in a WARN format string replaced with __func__.
* WARN_ON() in percpu_ref_reinit() converted to WARN_ON_ONCE().

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Kent Overstreet <kmo@daterainc.com>
This commit is contained in:
Tejun Heo 2014-09-24 13:31:48 -04:00
parent a223737019
commit 6251f9976a
2 changed files with 22 additions and 17 deletions

View file

@ -115,8 +115,10 @@ static inline bool __pcpu_ref_alive(struct percpu_ref *ref,
* percpu_ref_get - increment a percpu refcount
* @ref: percpu_ref to get
*
* Analagous to atomic_inc().
*/
* Analagous to atomic_long_inc().
*
* This function is safe to call as long as @ref is between init and exit.
*/
static inline void percpu_ref_get(struct percpu_ref *ref)
{
unsigned long __percpu *pcpu_count;
@ -138,12 +140,12 @@ static inline void percpu_ref_get(struct percpu_ref *ref)
* Increment a percpu refcount unless its count already reached zero.
* Returns %true on success; %false on failure.
*
* The caller is responsible for ensuring that @ref stays accessible.
* This function is safe to call as long as @ref is between init and exit.
*/
static inline bool percpu_ref_tryget(struct percpu_ref *ref)
{
unsigned long __percpu *pcpu_count;
int ret = false;
int ret;
rcu_read_lock_sched();
@ -166,12 +168,13 @@ static inline bool percpu_ref_tryget(struct percpu_ref *ref)
* Increment a percpu refcount unless it has already been killed. Returns
* %true on success; %false on failure.
*
* Completion of percpu_ref_kill() in itself doesn't guarantee that tryget
* will fail. For such guarantee, percpu_ref_kill_and_confirm() should be
* used. After the confirm_kill callback is invoked, it's guaranteed that
* no new reference will be given out by percpu_ref_tryget().
* Completion of percpu_ref_kill() in itself doesn't guarantee that this
* function will fail. For such guarantee, percpu_ref_kill_and_confirm()
* should be used. After the confirm_kill callback is invoked, it's
* guaranteed that no new reference will be given out by
* percpu_ref_tryget_live().
*
* The caller is responsible for ensuring that @ref stays accessible.
* This function is safe to call as long as @ref is between init and exit.
*/
static inline bool percpu_ref_tryget_live(struct percpu_ref *ref)
{
@ -196,6 +199,8 @@ static inline bool percpu_ref_tryget_live(struct percpu_ref *ref)
*
* Decrement the refcount, and if 0, call the release function (which was passed
* to percpu_ref_init())
*
* This function is safe to call as long as @ref is between init and exit.
*/
static inline void percpu_ref_put(struct percpu_ref *ref)
{
@ -216,6 +221,8 @@ static inline void percpu_ref_put(struct percpu_ref *ref)
* @ref: percpu_ref to test
*
* Returns %true if @ref reached zero.
*
* This function is safe to call as long as @ref is between init and exit.
*/
static inline bool percpu_ref_is_zero(struct percpu_ref *ref)
{