The code of attaching is unfolded in create_worker(). Separating this code out will make the codes more clear.
Signed-off-by: Lai Jiangshan <la...@cn.fujitsu.com> --- kernel/workqueue.c | 55 +++++++++++++++++++++++++++++++++------------------ 1 files changed, 35 insertions(+), 20 deletions(-) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 728b515..4d021e0 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -66,7 +66,7 @@ enum { * * Note that DISASSOCIATED should be flipped only while holding * attach_mutex to avoid changing binding state while - * create_worker() is in progress. + * worker_attach_to_pool() is in progress. */ POOL_DISASSOCIATED = 1 << 2, /* cpu can't serve workers */ POOL_FREEZING = 1 << 3, /* freeze in progress */ @@ -1683,6 +1683,39 @@ static struct worker *alloc_worker(void) } /** + * worker_attach_to_pool() - attach the worker to the pool + * @worker: worker to be attached + * @pool: the target pool + * + * Attach the worker to the pool, thus the %WORKER_UNBOUND flag and + * cpu-binding of the worker are kept coordination with the pool + * across cpu-[un]hotplug. + */ +static void worker_attach_to_pool(struct worker *worker, + struct worker_pool *pool) +{ + mutex_lock(&pool->attach_mutex); + + /* + * set_cpus_allowed_ptr() will fail if the cpumask doesn't have any + * online CPUs. It'll be re-applied when any of the CPUs come up. + */ + set_cpus_allowed_ptr(worker->task, pool->attrs->cpumask); + + /* + * The pool->attach_mutex ensures %POOL_DISASSOCIATED remains + * stable across this function. See the comments above the + * flag definition for details. + */ + if (pool->flags & POOL_DISASSOCIATED) + worker->flags |= WORKER_UNBOUND; + + list_add_tail(&worker->node, &pool->workers); + + mutex_unlock(&pool->attach_mutex); +} + +/** * worker_detach_from_pool() - detach the worker from the pool * @worker: worker which is attached to its pool * @pool: attached pool @@ -1753,26 +1786,8 @@ static struct worker *create_worker(struct worker_pool *pool) /* prevent userland from meddling with cpumask of workqueue workers */ worker->task->flags |= PF_NO_SETAFFINITY; - mutex_lock(&pool->attach_mutex); - - /* - * set_cpus_allowed_ptr() will fail if the cpumask doesn't have any - * online CPUs. It'll be re-applied when any of the CPUs come up. - */ - set_cpus_allowed_ptr(worker->task, pool->attrs->cpumask); - - /* - * The pool->attach_mutex ensures %POOL_DISASSOCIATED - * remains stable across this function. See the comments above the - * flag definition for details. - */ - if (pool->flags & POOL_DISASSOCIATED) - worker->flags |= WORKER_UNBOUND; - /* successful, attach the worker to the pool */ - list_add_tail(&worker->node, &pool->workers); - - mutex_unlock(&pool->attach_mutex); + worker_attach_to_pool(worker, pool); return worker; -- 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/