[PATCH 4/6] workqueue: separate out worker_pool flags

Tejun Heo
2012-07-09T18:42:14Z

GCWQ_MANAGE_WORKERS, GCWQ_MANAGING_WORKERS and GCWQ_HIGHPRI_PENDING
are per-pool properties. Add worker_pool->flags and make the above
three flags per-pool flags.

The changes in this patch are mechanical and don't caues any
functional difference. This is to prepare for multiple pools per
gcwq.

Signed-off-by: Tejun Heo <tj@kernel.org>
---
kernel/workqueue.c | 47 +++++++++++++++++++++++++----------------------
1 files changed, 25 insertions(+), 22 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 9f82c25..e700dcc 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -46,11 +46,13 @@

enum {
/* global_cwq flags */
- GCWQ_MANAGE_WORKERS = 1 << 0, /* need to manage workers */
- GCWQ_MANAGING_WORKERS = 1 << 1, /* managing workers */
- GCWQ_DISASSOCIATED = 1 << 2, /* cpu can't serve workers */
- GCWQ_FREEZING = 1 << 3, /* freeze in progress */
- GCWQ_HIGHPRI_PENDING = 1 << 4, /* highpri works on queue */
+ GCWQ_DISASSOCIATED = 1 << 0, /* cpu can't serve workers */
+ GCWQ_FREEZING = 1 << 1, /* freeze in progress */
+
+ /* pool flags */
+ POOL_MANAGE_WORKERS = 1 << 0, /* need to manage workers */
+ POOL_MANAGING_WORKERS = 1 << 1, /* managing workers */
+ POOL_HIGHPRI_PENDING = 1 << 2, /* highpri works on queue */

/* worker flags */
WORKER_STARTED = 1 << 0, /* started */
@@ -142,6 +144,7 @@ struct worker {

struct worker_pool {
struct global_cwq *gcwq; /* I: the owning gcwq */
+ unsigned int flags; /* X: flags */

struct list_head worklist; /* L: list of pending works */
int nr_workers; /* L: total number of workers */
@@ -583,7 +586,7 @@ static struct global_cwq *get_work_gcwq(struct work_struct *work)
static bool __need_more_worker(struct worker_pool *pool)
{
return !atomic_read(get_pool_nr_running(pool)) ||
- pool->gcwq->flags & GCWQ_HIGHPRI_PENDING;
+ (pool->flags & POOL_HIGHPRI_PENDING);
}

/*
@@ -612,7 +615,7 @@ static bool keep_working(struct worker_pool *pool)

return !list_empty(&pool->worklist) &&
(atomic_read(nr_running) <= 1 ||
- pool->gcwq->flags & GCWQ_HIGHPRI_PENDING);
+ (pool->flags & POOL_HIGHPRI_PENDING));
}

/* Do we need a new worker? Called from manager. */
@@ -625,13 +628,13 @@ static bool need_to_create_worker(struct worker_pool *pool)
static bool need_to_manage_workers(struct worker_pool *pool)
{
return need_to_create_worker(pool) ||
- pool->gcwq->flags & GCWQ_MANAGE_WORKERS;
+ (pool->flags & POOL_MANAGE_WORKERS);
}

/* Do we have too many workers and should some go away? */
static bool too_many_workers(struct worker_pool *pool)
{
- bool managing = pool->gcwq->flags & GCWQ_MANAGING_WORKERS;
+ bool managing = pool->flags & POOL_MANAGING_WORKERS;
int nr_idle = pool->nr_idle + managing; /* manager is considered idle */
int nr_busy = pool->nr_workers - nr_idle;

@@ -889,7 +892,7 @@ static struct worker *find_worker_executing_work(struct global_cwq *gcwq,
* position for the work. If @cwq is for HIGHPRI wq, the work is
* queued at the head of the queue but in FIFO order with respect to
* other HIGHPRI works; otherwise, at the end of the queue. This
- * function also sets GCWQ_HIGHPRI_PENDING flag to hint @pool that
+ * function also sets POOL_HIGHPRI_PENDING flag to hint @pool that
* there are HIGHPRI works pending.
*
* CONTEXT:
@@ -913,7 +916,7 @@ static inline struct list_head *pool_determine_ins_pos(struct worker_pool *pool,
break;
}

- pool->gcwq->flags |= GCWQ_HIGHPRI_PENDING;
+ pool->flags |= POOL_HIGHPRI_PENDING;
return &twork->entry;
}

@@ -1500,7 +1503,7 @@ static void idle_worker_timeout(unsigned long __pool)
mod_timer(&pool->idle_timer, expires);
else {
/* it's been idle for too long, wake up manager */
- gcwq->flags |= GCWQ_MANAGE_WORKERS;
+ pool->flags |= POOL_MANAGE_WORKERS;
wake_up_worker(pool);
}
}
@@ -1680,11 +1683,11 @@ static bool manage_workers(struct worker *worker)
struct global_cwq *gcwq = pool->gcwq;
bool ret = false;

- if (gcwq->flags & GCWQ_MANAGING_WORKERS)
+ if (pool->flags & POOL_MANAGING_WORKERS)
return ret;

- gcwq->flags &= ~GCWQ_MANAGE_WORKERS;
- gcwq->flags |= GCWQ_MANAGING_WORKERS;
+ pool->flags &= ~POOL_MANAGE_WORKERS;
+ pool->flags |= POOL_MANAGING_WORKERS;

/*
* Destroy and then create so that may_start_working() is true
@@ -1693,7 +1696,7 @@ static bool manage_workers(struct worker *worker)
ret |= maybe_destroy_workers(pool);
ret |= maybe_create_worker(pool);

- gcwq->flags &= ~GCWQ_MANAGING_WORKERS;
+ pool->flags &= ~POOL_MANAGING_WORKERS;

/*
* The trustee might be waiting to take over the manager
@@ -1872,7 +1875,7 @@ __acquires(&gcwq->lock)
* If HIGHPRI_PENDING, check the next work, and, if HIGHPRI,
* wake up another worker; otherwise, clear HIGHPRI_PENDING.
*/
- if (unlikely(gcwq->flags & GCWQ_HIGHPRI_PENDING)) {
+ if (unlikely(pool->flags & POOL_HIGHPRI_PENDING)) {
struct work_struct *nwork = list_first_entry(&pool->worklist,
struct work_struct, entry);

@@ -1880,7 +1883,7 @@ __acquires(&gcwq->lock)
get_work_cwq(nwork)->wq->flags & WQ_HIGHPRI)
wake_up_worker(pool);
else
- gcwq->flags &= ~GCWQ_HIGHPRI_PENDING;
+ pool->flags &= ~POOL_HIGHPRI_PENDING;
}

/*
@@ -3360,10 +3363,10 @@ static int __cpuinit trustee_thread(void *__gcwq)
* cancelled.
*/
BUG_ON(gcwq->cpu != smp_processor_id());
- rc = trustee_wait_event(!(gcwq->flags & GCWQ_MANAGING_WORKERS));
+ rc = trustee_wait_event(!(gcwq->pool.flags & POOL_MANAGING_WORKERS));
BUG_ON(rc < 0);

- gcwq->flags |= GCWQ_MANAGING_WORKERS;
+ gcwq->pool.flags |= POOL_MANAGING_WORKERS;

list_for_each_entry(worker, &gcwq->pool.idle_list, entry)
worker->flags |= WORKER_ROGUE;
@@ -3487,7 +3490,7 @@ static int __cpuinit trustee_thread(void *__gcwq)
}

/* relinquish manager role */
- gcwq->flags &= ~GCWQ_MANAGING_WORKERS;
+ gcwq->pool.flags &= ~POOL_MANAGING_WORKERS;

/* notify completion */
gcwq->trustee = NULL;
@@ -3604,7 +3607,7 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb,
spin_unlock_irq(&gcwq->lock);
kthread_bind(gcwq->pool.first_idle->task, cpu);
spin_lock_irq(&gcwq->lock);
- gcwq->flags |= GCWQ_MANAGE_WORKERS;
+ gcwq->pool.flags |= POOL_MANAGE_WORKERS;
start_worker(gcwq->pool.first_idle);
gcwq->pool.first_idle = NULL;
break;
--
1.7.7.3