diff options
| -rw-r--r-- | kernel/workqueue.c | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 7dd8e7bcec51..e933979678e5 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -122,6 +122,9 @@ enum { * W: workqueue_lock protected. * * R: workqueue_lock protected for writes. Sched-RCU protected for reads. + * + * FR: wq->flush_mutex and workqueue_lock protected for writes. Sched-RCU + * protected for reads. */ /* struct worker is defined in workqueue_internal.h */ @@ -185,7 +188,7 @@ struct pool_workqueue { int nr_active; /* L: nr of active works */ int max_active; /* L: max active works */ struct list_head delayed_works; /* L: delayed works */ - struct list_head pwqs_node; /* R: node on wq->pwqs */ + struct list_head pwqs_node; /* FR: node on wq->pwqs */ struct list_head mayday_node; /* W: node on wq->maydays */ /* @@ -214,7 +217,7 @@ struct wq_flusher { struct workqueue_struct { unsigned int flags; /* W: WQ_* flags */ struct pool_workqueue __percpu *cpu_pwqs; /* I: per-cpu pwq's */ - struct list_head pwqs; /* R: all pwqs of this wq */ + struct list_head pwqs; /* FR: all pwqs of this wq */ struct list_head list; /* W: list of all workqueues */ struct mutex flush_mutex; /* protects wq flushing */ @@ -3402,9 +3405,16 @@ static void pwq_unbound_release_workfn(struct work_struct *work) if (WARN_ON_ONCE(!(wq->flags & WQ_UNBOUND))) return; + /* + * Unlink @pwq. Synchronization against flush_mutex isn't strictly + * necessary on release but do it anyway. It's easier to verify + * and consistent with the linking path. + */ + mutex_lock(&wq->flush_mutex); spin_lock_irq(&workqueue_lock); list_del_rcu(&pwq->pwqs_node); spin_unlock_irq(&workqueue_lock); + mutex_unlock(&wq->flush_mutex); put_unbound_pool(pool); call_rcu_sched(&pwq->rcu, rcu_free_pwq); @@ -3432,7 +3442,18 @@ static void init_and_link_pwq(struct pool_workqueue *pwq, INIT_LIST_HEAD(&pwq->mayday_node); INIT_WORK(&pwq->unbound_release_work, pwq_unbound_release_workfn); + /* + * Link @pwq and set the matching work_color. This is synchronized + * with flush_mutex to avoid confusing flush_workqueue(). + */ + mutex_lock(&wq->flush_mutex); + spin_lock_irq(&workqueue_lock); + + pwq->work_color = wq->work_color; list_add_tail_rcu(&pwq->pwqs_node, &wq->pwqs); + + spin_unlock_irq(&workqueue_lock); + mutex_unlock(&wq->flush_mutex); } static int alloc_and_link_pwqs(struct workqueue_struct *wq) |
