Re: [PATCH] percpu_ref: Fix comment regarding percpu_ref_init flags
From: Ira Weiny
Date: Wed Feb 05 2020 - 23:28:15 EST
On Mon, Dec 09, 2019 at 01:54:20PM -0800, 'Ira Weiny' wrote:
> From: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> The comment for percpu_ref_init() implies that using
> PERCPU_REF_ALLOW_REINIT will cause the refcount to start at 0. But
> this is not true. PERCPU_REF_ALLOW_REINIT starts the count at 1 as
> if the flags were zero. Add this fact to the kernel doc comment.
Did this get picked up? Or am I wrong in the comment?
Ira
>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> ---
> lib/percpu-refcount.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c
> index 4f6c6ebbbbde..48d7fcff70b6 100644
> --- a/lib/percpu-refcount.c
> +++ b/lib/percpu-refcount.c
> @@ -50,9 +50,9 @@ static unsigned long __percpu *percpu_count_ptr(struct percpu_ref *ref)
> * @flags: PERCPU_REF_INIT_* flags
> * @gfp: allocation mask to use
> *
> - * Initializes @ref. If @flags is zero, @ref starts in percpu mode with a
> - * refcount of 1; analagous to atomic_long_set(ref, 1). See the
> - * definitions of PERCPU_REF_INIT_* flags for flag behaviors.
> + * Initializes @ref. If @flags is zero or PERCPU_REF_ALLOW_REINIT, @ref starts
> + * in percpu mode with a refcount of 1; analagous to atomic_long_set(ref, 1).
> + * See the definitions of PERCPU_REF_INIT_* flags for flag behaviors.
> *
> * Note that @release must not sleep - it may potentially be called from RCU
> * callback context by percpu_ref_kill().
> --
> 2.21.0
>