Re: [PATCH] Make clocksource insert entry more efficiently

From: Minfei Huang
Date: Sat Apr 30 2016 - 06:18:03 EST


Ping.

Any comment is appreciate.

Thanks
Minfei

On 04/25/16 at 05:20P, Minfei Huang wrote:
> It is unnecessary to continue looping the list, if we find there is an
> entry that the value of rating is smaller than the new one. It is safe
> to be out the loop, because all of entry are inserted in descending
> order.
>
> Signed-off-by: Minfei Huang <mnghuan@xxxxxxxxx>
> ---
> kernel/time/clocksource.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
> index 56ece14..6a5a310 100644
> --- a/kernel/time/clocksource.c
> +++ b/kernel/time/clocksource.c
> @@ -669,10 +669,12 @@ static void clocksource_enqueue(struct clocksource *cs)
> struct list_head *entry = &clocksource_list;
> struct clocksource *tmp;
>
> - list_for_each_entry(tmp, &clocksource_list, list)
> + list_for_each_entry(tmp, &clocksource_list, list) {
> /* Keep track of the place, where to insert */
> - if (tmp->rating >= cs->rating)
> - entry = &tmp->list;
> + if (tmp->rating < cs->rating)
> + break;
> + entry = &tmp->list;
> + }
> list_add(&cs->list, entry);
> }
>
> --
> 2.6.3
>