worker_maybe_bind_and_lock() currently takes @worker but only cares about @worker->pool. This patch updates worker_maybe_bind_and_lock() to take @pool instead of @worker. This will be used to better define synchronization rules regarding rescuer->pool updates. This doesn't introduce any functional change. tj: Updated the comments and description.
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| @@ -1504,8 +1504,10 @@ static void worker_leave_idle(struct worker *worker) · 1503 unmodified lines | |||
| 1504 | } | 1504 | } |
| 1505 | 1505 | ||
| 1506 | /** | 1506 | /** |
| 1507 | * worker_maybe_bind_and_lock - bind worker to its cpu if possible and lock pool | 1507 | * worker_maybe_bind_and_lock - try to bind %current to worker_pool and lock it |
| 1508 | * @worker: self | 1508 | * @pool: target worker_pool |
| 1509 | * | ||
| 1510 | * Bind %current to the cpu of @pool if it is associated and lock @pool. | ||
| 1509 | * | 1511 | * |
| 1510 | * Works which are scheduled while the cpu is online must at least be | 1512 | * Works which are scheduled while the cpu is online must at least be |
| 1511 | * scheduled to a worker which is bound to the cpu so that if they are | 1513 | * scheduled to a worker which is bound to the cpu so that if they are |
| @@ -1533,11 +1535,9 @@ static void worker_leave_idle(struct worker *worker) · 21 unmodified lines | |||
| 1533 | * %true if the associated pool is online (@worker is successfully | 1535 | * %true if the associated pool is online (@worker is successfully |
| 1534 | * bound), %false if offline. | 1536 | * bound), %false if offline. |
| 1535 | */ | 1537 | */ |
| 1536 | static bool worker_maybe_bind_and_lock(struct worker *worker) | 1538 | static bool worker_maybe_bind_and_lock(struct worker_pool *pool) |
| 1537 | __acquires(&pool->lock) | 1539 | __acquires(&pool->lock) |
| 1538 | { | 1540 | { |
| 1539 | struct worker_pool *pool = worker->pool; | ||
| 1540 | |||
| 1541 | while (true) { | 1541 | while (true) { |
| 1542 | /* | 1542 | /* |
| 1543 | * The following call may fail, succeed or succeed | 1543 | * The following call may fail, succeed or succeed |
| @@ -1575,7 +1575,7 @@ __acquires(&pool->lock) · 31 unmodified lines | |||
| 1575 | static void idle_worker_rebind(struct worker *worker) | 1575 | static void idle_worker_rebind(struct worker *worker) |
| 1576 | { | 1576 | { |
| 1577 | /* CPU may go down again inbetween, clear UNBOUND only on success */ | 1577 | /* CPU may go down again inbetween, clear UNBOUND only on success */ |
| 1578 | if (worker_maybe_bind_and_lock(worker)) | 1578 | if (worker_maybe_bind_and_lock(worker->pool)) |
| 1579 | worker_clr_flags(worker, WORKER_UNBOUND); | 1579 | worker_clr_flags(worker, WORKER_UNBOUND); |
| 1580 | 1580 | ||
| 1581 | /* rebind complete, become available again */ | 1581 | /* rebind complete, become available again */ |
| @@ -1593,7 +1593,7 @@ static void busy_worker_rebind_fn(struct work_struct *work) · 11 unmodified lines | |||
| 1593 | { | 1593 | { |
| 1594 | struct worker *worker = container_of(work, struct worker, rebind_work); | 1594 | struct worker *worker = container_of(work, struct worker, rebind_work); |
| 1595 | 1595 | ||
| 1596 | if (worker_maybe_bind_and_lock(worker)) | 1596 | if (worker_maybe_bind_and_lock(worker->pool)) |
| 1597 | worker_clr_flags(worker, WORKER_UNBOUND); | 1597 | worker_clr_flags(worker, WORKER_UNBOUND); |
| 1598 | 1598 | ||
| 1599 | spin_unlock_irq(&worker->pool->lock); | 1599 | spin_unlock_irq(&worker->pool->lock); |
| @@ -2038,7 +2038,7 @@ static bool manage_workers(struct worker *worker) · 438 unmodified lines | |||
| 2038 | * on @pool's current state. Try it and adjust | 2038 | * on @pool's current state. Try it and adjust |
| 2039 | * %WORKER_UNBOUND accordingly. | 2039 | * %WORKER_UNBOUND accordingly. |
| 2040 | */ | 2040 | */ |
| 2041 | if (worker_maybe_bind_and_lock(worker)) | 2041 | if (worker_maybe_bind_and_lock(pool)) |
| 2042 | worker->flags &= ~WORKER_UNBOUND; | 2042 | worker->flags &= ~WORKER_UNBOUND; |
| 2043 | else | 2043 | else |
| 2044 | worker->flags |= WORKER_UNBOUND; | 2044 | worker->flags |= WORKER_UNBOUND; |
| @@ -2358,7 +2358,7 @@ repeat: · 313 unmodified lines | |||
| 2358 | 2358 | ||
| 2359 | /* migrate to the target cpu if possible */ | 2359 | /* migrate to the target cpu if possible */ |
| 2360 | rescuer->pool = pool; | 2360 | rescuer->pool = pool; |
| 2361 | worker_maybe_bind_and_lock(rescuer); | 2361 | worker_maybe_bind_and_lock(pool); |
| 2362 | 2362 | ||
| 2363 | /* | 2363 | /* |
| 2364 | * Slurp in all works issued via this workqueue and | 2364 | * Slurp in all works issued via this workqueue and |