Re: [PATCH] nvme: Remove redundant validation in nvme_start_ctrl()

From: Baolin Wang
Date: Mon Jul 13 2020 - 23:24:03 EST


On Mon, Jul 13, 2020 at 11:58:18PM +0000, Chaitanya Kulkarni wrote:
> On 7/12/20 23:31, Baolin Wang wrote:
> > We've already validated the 'kato' in nvme_start_keep_alive(), thus no
> > need to validate it again in nvme_start_ctrl(). Remove it.
> >
> > Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
> > ---
> > drivers/nvme/host/core.c | 3 +--
> > 1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> > index 3d00ea4..a95e26e 100644
> > --- a/drivers/nvme/host/core.c
> > +++ b/drivers/nvme/host/core.c
> > @@ -4313,8 +4313,7 @@ void nvme_stop_ctrl(struct nvme_ctrl *ctrl)
> >
> > void nvme_start_ctrl(struct nvme_ctrl *ctrl)
> > {
> > - if (ctrl->kato)
> > - nvme_start_keep_alive(ctrl);
> > + nvme_start_keep_alive(ctrl);
> >
> > nvme_enable_aen(ctrl);
> >
> >
>
> Since start keep alive is so small to make a function call how about we
> in-line the call ? untested patch :-

I am Okay about your suggestion. Will send v2 with your suggested-by tag
if no other objection. Thanks.

>
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index 09abf2ca33f5..c7289c23658a 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -4311,8 +4311,9 @@ EXPORT_SYMBOL_GPL(nvme_stop_ctrl);
>
> void nvme_start_ctrl(struct nvme_ctrl *ctrl)
> {
> + /* if ctrl keep alive time out is set start keep alive */
> if (ctrl->kato)
> - nvme_start_keep_alive(ctrl);
> + queue_delayed_work(nvme_wq, &ctrl->ka_work, ctrl->kato *
> HZ);
>
> nvme_enable_aen(ctrl);
>
> root@iouring nvme (xarray) # git diff
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index 09abf2ca33f5..08e1a6826b08 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -1031,14 +1031,6 @@ static void nvme_keep_alive_work(struct
> work_struct *work)
> }
> }
>
> -static void nvme_start_keep_alive(struct nvme_ctrl *ctrl)
> -{
> - if (unlikely(ctrl->kato == 0))
> - return;
> -
> - queue_delayed_work(nvme_wq, &ctrl->ka_work, ctrl->kato * HZ);
> -}
> -
> void nvme_stop_keep_alive(struct nvme_ctrl *ctrl)
> {
> if (unlikely(ctrl->kato == 0))
> @@ -4311,8 +4303,9 @@ EXPORT_SYMBOL_GPL(nvme_stop_ctrl);
>
> void nvme_start_ctrl(struct nvme_ctrl *ctrl)
> {
> + /* if ctrl keep alive time out is set start keep alive */
> if (ctrl->kato)
> - nvme_start_keep_alive(ctrl);
> + queue_delayed_work(nvme_wq, &ctrl->ka_work, ctrl->kato *
> HZ);
>
> nvme_enable_aen(ctrl);
>
>