Re: [PATCH 11/25] pm: don't use [delayed_]work_pending()

From: Rafael J. Wysocki
Date: Sat Dec 22 2012 - 06:48:15 EST


On Friday, December 21, 2012 05:57:01 PM Tejun Heo wrote:
> There's no need to test whether a (delayed) work item in pending
> before queueing, flushing or cancelling it. Most uses are unnecessary
> and quite a few of them are buggy.

Can you please say why they are buggy?

> Remove unnecessary pending tests from pm autosleep and qos. Only
> compile tested.
>
> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rjw@xxxxxxx>
> Cc: linux-pm@xxxxxxxxxxxxxxx
> ---
> Please let me know how this patch should be routed. I can take it
> through the workqueue tree if necessary.

I can take it. I will send a pull request with fixes later in the cycle
(maybe even before -rc2).

Thanks,
Rafael


> kernel/power/autosleep.c | 2 +-
> kernel/power/qos.c | 9 +++------
> 2 files changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/kernel/power/autosleep.c b/kernel/power/autosleep.c
> index ca304046..c6422ff 100644
> --- a/kernel/power/autosleep.c
> +++ b/kernel/power/autosleep.c
> @@ -66,7 +66,7 @@ static DECLARE_WORK(suspend_work, try_to_suspend);
>
> void queue_up_suspend_work(void)
> {
> - if (!work_pending(&suspend_work) && autosleep_state > PM_SUSPEND_ON)
> + if (autosleep_state > PM_SUSPEND_ON)
> queue_work(autosleep_wq, &suspend_work);
> }
>
> diff --git a/kernel/power/qos.c b/kernel/power/qos.c
> index 9322ff7..587ddde 100644
> --- a/kernel/power/qos.c
> +++ b/kernel/power/qos.c
> @@ -359,8 +359,7 @@ void pm_qos_update_request(struct pm_qos_request *req,
> return;
> }
>
> - if (delayed_work_pending(&req->work))
> - cancel_delayed_work_sync(&req->work);
> + cancel_delayed_work_sync(&req->work);
>
> if (new_value != req->node.prio)
> pm_qos_update_target(
> @@ -386,8 +385,7 @@ void pm_qos_update_request_timeout(struct pm_qos_request *req, s32 new_value,
> "%s called for unknown object.", __func__))
> return;
>
> - if (delayed_work_pending(&req->work))
> - cancel_delayed_work_sync(&req->work);
> + cancel_delayed_work_sync(&req->work);
>
> if (new_value != req->node.prio)
> pm_qos_update_target(
> @@ -416,8 +414,7 @@ void pm_qos_remove_request(struct pm_qos_request *req)
> return;
> }
>
> - if (delayed_work_pending(&req->work))
> - cancel_delayed_work_sync(&req->work);
> + cancel_delayed_work_sync(&req->work);
>
> pm_qos_update_target(pm_qos_array[req->pm_qos_class]->constraints,
> &req->node, PM_QOS_REMOVE_REQ,
>
--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/