summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--fs/fs-writeback.c23
-rw-r--r--include/linux/backing-dev.h2
-rw-r--r--mm/backing-dev.c13
3 files changed, 28 insertions, 10 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index f79f641de4ff..387213ac2608 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -87,16 +87,29 @@ static inline struct inode *wb_inode(struct list_head *head)
#define CREATE_TRACE_POINTS
#include <trace/events/writeback.h>
+static void bdi_wakeup_thread(struct backing_dev_info *bdi)
+{
+ spin_lock_bh(&bdi->wb_lock);
+ if (test_bit(BDI_registered, &bdi->state))
+ mod_delayed_work(bdi_wq, &bdi->wb.dwork, 0);
+ spin_unlock_bh(&bdi->wb_lock);
+}
+
static void bdi_queue_work(struct backing_dev_info *bdi,
struct wb_writeback_work *work)
{
trace_writeback_queue(bdi, work);
spin_lock_bh(&bdi->wb_lock);
+ if (!test_bit(BDI_registered, &bdi->state)) {
+ if (work->done)
+ complete(work->done);
+ goto out_unlock;
+ }
list_add_tail(&work->list, &bdi->work_list);
- spin_unlock_bh(&bdi->wb_lock);
-
mod_delayed_work(bdi_wq, &bdi->wb.dwork, 0);
+out_unlock:
+ spin_unlock_bh(&bdi->wb_lock);
}
static void
@@ -112,7 +125,7 @@ __bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages,
work = kzalloc(sizeof(*work), GFP_ATOMIC);
if (!work) {
trace_writeback_nowork(bdi);
- mod_delayed_work(bdi_wq, &bdi->wb.dwork, 0);
+ bdi_wakeup_thread(bdi);
return;
}
@@ -159,7 +172,7 @@ void bdi_start_background_writeback(struct backing_dev_info *bdi)
* writeback as soon as there is no other work to do.
*/
trace_writeback_wake_background(bdi);
- mod_delayed_work(bdi_wq, &bdi->wb.dwork, 0);
+ bdi_wakeup_thread(bdi);
}
/*
@@ -1016,7 +1029,7 @@ void bdi_writeback_workfn(struct work_struct *work)
current->flags |= PF_SWAPWRITE;
if (likely(!current_is_workqueue_rescuer() ||
- list_empty(&bdi->bdi_list))) {
+ !test_bit(BDI_registered, &bdi->state))) {
/*
* The normal path. Keep writing back @bdi until its
* work_list is empty. Note that this path is also taken
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index c3881553f7d1..4cfdbf28fc6a 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -95,7 +95,7 @@ struct backing_dev_info {
unsigned int max_ratio, max_prop_frac;
struct bdi_writeback wb; /* default writeback info for this bdi */
- spinlock_t wb_lock; /* protects work_list */
+ spinlock_t wb_lock; /* protects work_list & wb.dwork scheduling */
struct list_head work_list;
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 95e437435788..eea1a9dfac38 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -296,7 +296,10 @@ void bdi_wakeup_thread_delayed(struct backing_dev_info *bdi)
unsigned long timeout;
timeout = msecs_to_jiffies(dirty_writeback_interval * 10);
- queue_delayed_work(bdi_wq, &bdi->wb.dwork, timeout);
+ spin_lock_bh(&bdi->wb_lock);
+ if (test_bit(BDI_registered, &bdi->state))
+ queue_delayed_work(bdi_wq, &bdi->wb.dwork, timeout);
+ spin_unlock_bh(&bdi->wb_lock);
}
/*
@@ -309,9 +312,6 @@ static void bdi_remove_from_list(struct backing_dev_info *bdi)
spin_unlock_bh(&bdi_lock);
synchronize_rcu_expedited();
-
- /* bdi_list is now unused, clear it to mark @bdi dying */
- INIT_LIST_HEAD(&bdi->bdi_list);
}
int bdi_register(struct backing_dev_info *bdi, struct device *parent,
@@ -362,6 +362,11 @@ static void bdi_wb_shutdown(struct backing_dev_info *bdi)
*/
bdi_remove_from_list(bdi);
+ /* Make sure nobody queues further work */
+ spin_lock_bh(&bdi->wb_lock);
+ clear_bit(BDI_registered, &bdi->state);
+ spin_unlock_bh(&bdi->wb_lock);
+
/*
* Drain work list and shutdown the delayed_work. At this point,
* @bdi->bdi_list is empty telling bdi_Writeback_workfn() that @bdi