diff options
| author | Andrea Parri <andrea.parri@amarulasolutions.com> | 2018-08-14 21:41:06 +0300 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2018-09-27 12:59:58 +0300 |
| commit | 5aac49378742a52bbe8af3d25bc51b487be7b17f (patch) | |
| tree | 766b8ef63da32898842943c4d4df7d63b9b04af1 /net/bluetooth/hidp/core.c | |
| parent | 1042caa79e9351b81ed19dc8d2d7fd6ff51a4422 (diff) | |
| download | linux-5aac49378742a52bbe8af3d25bc51b487be7b17f.tar.xz | |
Bluetooth: Remove unnecessary smp_mb__{before,after}_atomic
The barriers are unneeded; wait_woken() and woken_wake_function()
already provide us with the required synchronization: remove them
and document that we're relying on the (implicit) synchronization
provided by wait_woken() and woken_wake_function().
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Reviewed-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'net/bluetooth/hidp/core.c')
| -rw-r--r-- | net/bluetooth/hidp/core.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c index 253975cce943..3734dc1788b4 100644 --- a/net/bluetooth/hidp/core.c +++ b/net/bluetooth/hidp/core.c @@ -1074,6 +1074,10 @@ static int hidp_session_start_sync(struct hidp_session *session) static void hidp_session_terminate(struct hidp_session *session) { atomic_inc(&session->terminate); + /* + * See the comment preceding the call to wait_woken() + * in hidp_session_run(). + */ wake_up_interruptible(&hidp_session_wq); } @@ -1193,8 +1197,6 @@ static void hidp_session_run(struct hidp_session *session) * thread is woken up by ->sk_state_changed(). */ - /* Ensure session->terminate is updated */ - smp_mb__before_atomic(); if (atomic_read(&session->terminate)) break; @@ -1228,14 +1230,15 @@ static void hidp_session_run(struct hidp_session *session) hidp_process_transmit(session, &session->ctrl_transmit, session->ctrl_sock); + /* + * wait_woken() performs the necessary memory barriers + * for us; see the header comment for this primitive. + */ wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); } remove_wait_queue(&hidp_session_wq, &wait); atomic_inc(&session->terminate); - - /* Ensure session->terminate is updated */ - smp_mb__after_atomic(); } static int hidp_session_wake_function(wait_queue_entry_t *wait, |