[PATCH 04/10] workqueue: use nr_cwqs_to_flush array

From: Lai Jiangshan
Date: Mon Sep 24 2012 - 06:06:15 EST


Each color uses its own nr_cwqs_to_flush[color].

This patch doesn't make any functional difference.

Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxx>
---
kernel/workqueue.c | 21 ++++++++++++---------
1 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 5439fb6..861b4c7 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -250,7 +250,7 @@ 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; /* flush in progress */
+ 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 */
struct list_head flusher_overflow; /* F: flush overflow list */
@@ -1036,7 +1036,7 @@ static void cwq_dec_nr_in_flight(struct cpu_workqueue_struct *cwq, int color)
* If this was the last cwq, wake up the first flusher. It
* will handle the rest.
*/
- if (atomic_dec_and_test(&cwq->wq->nr_cwqs_to_flush))
+ if (atomic_dec_and_test(&cwq->wq->nr_cwqs_to_flush[color]))
complete(&cwq->wq->first_flusher->done);
}

@@ -2540,8 +2540,8 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
* -1. If no cwq has in-flight commands at the specified color, all
* cwq->flush_color's stay at -1 and %false is returned. If any cwq
* has in flight commands, its cwq->flush_color is set to
- * @flush_color, @wq->nr_cwqs_to_flush is updated accordingly, cwq
- * wakeup logic is armed and %true is returned.
+ * @flush_color, @wq->nr_cwqs_to_flush[flush_color] is updated accordingly,
+ * cwq wakeup logic is armed and %true is returned.
*
* The caller should have initialized @wq->first_flusher prior to
* calling this function with non-negative @flush_color. If
@@ -2566,8 +2566,8 @@ static bool flush_workqueue_prep_cwqs(struct workqueue_struct *wq,
unsigned int cpu;

if (flush_color >= 0) {
- BUG_ON(atomic_read(&wq->nr_cwqs_to_flush));
- atomic_set(&wq->nr_cwqs_to_flush, 1);
+ BUG_ON(atomic_read(&wq->nr_cwqs_to_flush[flush_color]));
+ atomic_set(&wq->nr_cwqs_to_flush[flush_color], 1);
}

for_each_cwq_cpu(cpu, wq) {
@@ -2581,7 +2581,7 @@ static bool flush_workqueue_prep_cwqs(struct workqueue_struct *wq,

if (cwq->nr_in_flight[flush_color]) {
cwq->flush_color = flush_color;
- atomic_inc(&wq->nr_cwqs_to_flush);
+ atomic_inc(&wq->nr_cwqs_to_flush[flush_color]);
wait = true;
}
}
@@ -2594,7 +2594,8 @@ static bool flush_workqueue_prep_cwqs(struct workqueue_struct *wq,
spin_unlock_irq(&gcwq->lock);
}

- if (flush_color >= 0 && atomic_dec_and_test(&wq->nr_cwqs_to_flush))
+ if (flush_color >= 0 &&
+ atomic_dec_and_test(&wq->nr_cwqs_to_flush[flush_color]))
complete(&wq->first_flusher->done);

return wait;
@@ -3211,6 +3212,7 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
struct workqueue_struct *wq;
unsigned int cpu;
size_t namelen;
+ int color;

/* determine namelen, allocate wq and format name */
va_start(args, lock_name);
@@ -3239,7 +3241,8 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
wq->flags = flags;
wq->saved_max_active = max_active;
mutex_init(&wq->flush_mutex);
- atomic_set(&wq->nr_cwqs_to_flush, 0);
+ for (color = 0; color < WORK_NR_COLORS; color++)
+ atomic_set(&wq->nr_cwqs_to_flush[color], 0);
INIT_LIST_HEAD(&wq->flusher_queue);
INIT_LIST_HEAD(&wq->flusher_overflow);

--
1.7.4.4

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