[PATCH 1/2] workqueue: clear POOL_DISASSOCIATED in rebind_workers()

From: Lai Jiangshan
Date: Tue Jun 03 2014 - 03:29:04 EST


The commit a9ab775bcadf ("workqueue: directly restore CPU affinity of workers
from CPU_ONLINE") moved the pool->lock into rebind_workers() without also
moving "pool->flags &= ~POOL_DISASSOCIATED" into.

There is no wrong that "pool->flags &= ~POOL_DISASSOCIATED" is kept outside,
but there is no benefit either. We move it into rebind_workers() and
achieve these benefits:
1) better readability, POOL_DISASSOCIATED is cleared in rebind_workers()
as supposed.
2) when POOL_DISASSOCIATED is cleared, we can ensure that the running
workers of the pool are on the local CPU (pool->cpu).

Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxx>
---
kernel/workqueue.c | 5 +----
1 files changed, 1 insertions(+), 4 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 61381a2..5ae491e 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4535,6 +4535,7 @@ static void rebind_workers(struct worker_pool *pool)
pool->attrs->cpumask) < 0);

spin_lock_irq(&pool->lock);
+ pool->flags &= ~POOL_DISASSOCIATED;

for_each_pool_worker(worker, pool) {
unsigned int worker_flags = worker->flags;
@@ -4637,10 +4638,6 @@ static int workqueue_cpu_up_callback(struct notifier_block *nfb,
mutex_lock(&pool->attach_mutex);

if (pool->cpu == cpu) {
- spin_lock_irq(&pool->lock);
- pool->flags &= ~POOL_DISASSOCIATED;
- spin_unlock_irq(&pool->lock);
-
rebind_workers(pool);
} else if (pool->cpu < 0) {
restore_unbound_workers_cpumask(pool, cpu);
--
1.7.4.4

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