Use wq->first_flusher->flush_color instead.
If current task is the first_flusher, we use @flush_color
or work_next_color(flush_color) directly.
This patch doesn't make any functional difference.
Signed-off-by: Lai Jiangshan <la...@cn.fujitsu.com>
---
kernel/workqueue.c | 52 ++++++++++++++++++++--------------------------------
1 files changed, 20 insertions(+), 32 deletions(-)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index d78fe08..e703659 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -248,7 +248,6 @@ struct workqueue_struct {
struct mutex flush_mutex; /* protects wq flushing */
int work_color; /* F: current work color */
- int flush_color; /* F: current flush color */
atomic_t nr_cwqs_to_flush[WORK_NR_COLORS];
struct wq_flusher *first_flusher; /* F: first flusher */
struct list_head flusher_queue; /* F: flush waiters */
@@ -2555,7 +2554,7 @@ static bool workqueue_start_flush(struct workqueue_struct
*wq)
bool wait = false;
unsigned int cpu;
- BUG_ON(next_color == wq->flush_color);
+ BUG_ON(next_color == wq->first_flusher->flush_color);
wq->work_color = next_color;
BUG_ON(atomic_read(&wq->nr_cwqs_to_flush[flush_color]));
@@ -2614,29 +2613,23 @@ void flush_workqueue(struct workqueue_struct *wq)
next_color = work_next_color(wq->work_color);
this_flusher.flush_color = flush_color;
- if (next_color != wq->flush_color) {
- /* Color space is not full */
- if (!wq->first_flusher) {
- /* no flush in progress, become the first flusher */
- BUG_ON(wq->flush_color != flush_color);
-
- wq->first_flusher = &this_flusher;
-
- if (!workqueue_start_flush(wq)) {
- /* nothing to flush, done */
- wq_dec_flusher_ref(wq, flush_color);
- wq->flush_color = next_color;
- wq->first_flusher = NULL;
- goto out_unlock;
- }
+ if (!wq->first_flusher) {
+ /* no flush in progress, become the first flusher */
+ wq->first_flusher = &this_flusher;
+ if (!workqueue_start_flush(wq)) {
+ /* nothing to flush, done */
wq_dec_flusher_ref(wq, flush_color);
- } else {
- /* wait in queue */
- BUG_ON(wq->flush_color == this_flusher.flush_color);
- list_add_tail(&this_flusher.list, &wq->flusher_queue);
- workqueue_start_flush(wq);
+ wq->first_flusher = NULL;
+ goto out_unlock;
}
+
+ wq_dec_flusher_ref(wq, flush_color);
+ } else if (next_color != wq->first_flusher->flush_color) {
+ /* Color space is not full, wait in queue */
+ BUG_ON(wq->first_flusher->flush_color == flush_color);
+ list_add_tail(&this_flusher.list, &wq->flusher_queue);
+ workqueue_start_flush(wq);
} else {
/*
* Oops, color space is full, queue it without starting flush.
@@ -2663,21 +2656,17 @@ void flush_workqueue(struct workqueue_struct *wq)
BUG_ON(wq->first_flusher != &this_flusher);
BUG_ON(!list_empty(&this_flusher.list));
- BUG_ON(wq->flush_color != this_flusher.flush_color);
/* complete all the flushers sharing the current flush color */
list_for_each_entry_safe(next, tmp, &wq->flusher_queue, list) {
- if (next->flush_color != wq->flush_color)
+ if (next->flush_color != flush_color)
break;
list_del_init(&next->list);
complete(&next->done);
}
- /* this flush_color is finished, advance by one */
- wq->flush_color = work_next_color(wq->flush_color);
-
if (list_empty(&wq->flusher_queue)) {
- BUG_ON(wq->flush_color != wq->work_color);
+ BUG_ON(work_next_color(flush_color) != wq->work_color);
wq->first_flusher = NULL;
goto out_unlock;
}
@@ -2686,9 +2675,6 @@ void flush_workqueue(struct workqueue_struct *wq)
* Need to flush more colors. Make the next flusher
* the new first flusher and arm it.
*/
- BUG_ON(wq->flush_color == wq->work_color);
- BUG_ON(wq->flush_color != next->flush_color);
-
last = list_entry(wq->flusher_queue.prev, struct wq_flusher, list);
list_del_init(&next->list);
wq->first_flusher = next;
@@ -2698,9 +2684,11 @@ void flush_workqueue(struct workqueue_struct *wq)
workqueue_start_flush(wq);
BUG_ON(work_next_color(last->flush_color) != wq->work_color);
+ BUG_ON(work_next_color(flush_color) != next->flush_color);
+ BUG_ON(next->flush_color == wq->work_color);
/* arm new first flusher */
- wq_dec_flusher_ref(wq, wq->flush_color);
+ wq_dec_flusher_ref(wq, next->flush_color);
out_unlock:
mutex_unlock(&wq->flush_mutex);
--
1.7.4.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
