[PATCH V2] workqueue: fix double unlock bug

[PATCH V2] workqueue: fix double unlock bug

[Daeseok Youn]

mutex_unlock() and put_pwq_unlocked() do not need to be called
when alloc_unbound_pwq() is failed.

And remove "if" condition for whether "pwq" is same as "wq->dfl_pwq"
when wq_calc_node_cpumask() returns false and just use "goto use_dfl_pwq"

Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
---
V2: replace "if condition" with "goto" as Lai's comment.

 kernel/workqueue.c |    7 ++-----
 1 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 0ee63af..9853067 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4087,10 +4087,7 @@ static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu,
 		if (cpumask_equal(cpumask, pwq->pool->attrs->cpumask))
 			goto out_unlock;
 	} else {
-		if (pwq == wq->dfl_pwq)
-			goto out_unlock;
-		else
-			goto use_dfl_pwq;
+		goto use_dfl_pwq;
 	}
 
 	mutex_unlock(&wq->mutex);
@@ -4100,7 +4097,7 @@ static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu,
 	if (!pwq) {
 		pr_warning("workqueue: allocation failed while updating NUMA affinity of \"%s\"\n",
 			   wq->name);
-		goto out_unlock;
+		return;
 	}
 
 	/*
-- 
1.7.4.4

Re: [PATCH V2] workqueue: fix double unlock bug

[Lai Jiangshan]

On Mon, Apr 14, 2014 at 6:41 PM, Daeseok Youn <daeseok.youn@gmail.com> wrote:
>
> mutex_unlock() and put_pwq_unlocked() do not need to be called
> when alloc_unbound_pwq() is failed.
>
> And remove "if" condition for whether "pwq" is same as "wq->dfl_pwq"
> when wq_calc_node_cpumask() returns false and just use "goto use_dfl_pwq"
>
> Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
> ---
> V2: replace "if condition" with "goto" as Lai's comment.
>
>  kernel/workqueue.c |    7 ++-----
>  1 files changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> index 0ee63af..9853067 100644
> --- a/kernel/workqueue.c
> +++ b/kernel/workqueue.c
> @@ -4087,10 +4087,7 @@ static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu,
>                 if (cpumask_equal(cpumask, pwq->pool->attrs->cpumask))
>                         goto out_unlock;
>         } else {
> -               if (pwq == wq->dfl_pwq)
> -                       goto out_unlock;
> -               else
> -                       goto use_dfl_pwq;
> +               goto use_dfl_pwq;
>         }
>
>         mutex_unlock(&wq->mutex);
> @@ -4100,7 +4097,7 @@ static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu,
>         if (!pwq) {
>                 pr_warning("workqueue: allocation failed while updating NUMA affinity of \"%s\"\n",
>                            wq->name);
> -               goto out_unlock;
> +               return;

Please acquire the  wq->mutex and goto use_dfl_pwq;

>         }
>
>         /*
> --
> 1.7.4.4
>
>
> --
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