Add a struct timer_list to struct gb_operation and use that to implement generic operation timeouts.
This simplifies the synchronous operation handling somewhat while also providing a generic timeout mechanism that drivers can use for asynchronous operations.
Signed-off-by: Johan Hovold johan@kernel.org --- drivers/staging/greybus/loopback.c | 1 + drivers/staging/greybus/operation.c | 50 ++++++++++++++++++++++++++----------- drivers/staging/greybus/operation.h | 2 ++ 3 files changed, 39 insertions(+), 14 deletions(-)
diff --git a/drivers/staging/greybus/loopback.c b/drivers/staging/greybus/loopback.c index 6c2a41c638c3..4bee33f62fd4 100644 --- a/drivers/staging/greybus/loopback.c +++ b/drivers/staging/greybus/loopback.c @@ -629,6 +629,7 @@ static int gb_loopback_async_operation(struct gb_loopback *gb, int type, mutex_lock(&gb->mutex); ret = gb_operation_request_send(operation, gb_loopback_async_operation_callback, + 0, GFP_KERNEL); if (ret) goto error; diff --git a/drivers/staging/greybus/operation.c b/drivers/staging/greybus/operation.c index 0123109a1070..3023012808d9 100644 --- a/drivers/staging/greybus/operation.c +++ b/drivers/staging/greybus/operation.c @@ -273,18 +273,40 @@ static void gb_operation_request_handle(struct gb_operation *operation) static void gb_operation_work(struct work_struct *work) { struct gb_operation *operation; + int ret;
operation = container_of(work, struct gb_operation, work);
- if (gb_operation_is_incoming(operation)) + if (gb_operation_is_incoming(operation)) { gb_operation_request_handle(operation); - else + } else { + ret = del_timer_sync(&operation->timer); + if (!ret) { + /* Cancel request message if scheduled by timeout. */ + if (gb_operation_result(operation) == -ETIMEDOUT) + gb_message_cancel(operation->request); + } + operation->callback(operation); + }
gb_operation_put_active(operation); gb_operation_put(operation); }
+static void gb_operation_timeout(unsigned long arg) +{ + struct gb_operation *operation = (void *)arg; + + if (gb_operation_result_set(operation, -ETIMEDOUT)) { + /* + * A stuck request message will be cancelled from the + * workqueue. + */ + queue_work(gb_operation_completion_wq, &operation->work); + } +} + static void gb_operation_message_init(struct gb_host_device *hd, struct gb_message *message, u16 operation_id, size_t payload_size, u8 type) @@ -518,6 +540,9 @@ gb_operation_create_common(struct gb_connection *connection, u8 type, gfp_flags)) { goto err_request; } + + setup_timer(&operation->timer, gb_operation_timeout, + (unsigned long)operation); }
operation->flags = op_flags; @@ -679,6 +704,7 @@ static void gb_operation_sync_callback(struct gb_operation *operation) * gb_operation_request_send() - send an operation request message * @operation: the operation to initiate * @callback: the operation completion callback + * @timeout: operation timeout in milliseconds, or zero for no timeout * @gfp: the memory flags to use for any allocations * * The caller has filled in any payload so the request message is ready to go. @@ -693,6 +719,7 @@ static void gb_operation_sync_callback(struct gb_operation *operation) */ int gb_operation_request_send(struct gb_operation *operation, gb_operation_callback callback, + unsigned int timeout, gfp_t gfp) { struct gb_connection *connection = operation->connection; @@ -742,6 +769,11 @@ int gb_operation_request_send(struct gb_operation *operation, if (ret) goto err_put_active;
+ if (timeout) { + operation->timer.expires = jiffies + msecs_to_jiffies(timeout); + add_timer(&operation->timer); + } + return 0;
err_put_active: @@ -763,26 +795,16 @@ int gb_operation_request_send_sync_timeout(struct gb_operation *operation, unsigned int timeout) { int ret; - unsigned long timeout_jiffies;
ret = gb_operation_request_send(operation, gb_operation_sync_callback, - GFP_KERNEL); + timeout, GFP_KERNEL); if (ret) return ret;
- if (timeout) - timeout_jiffies = msecs_to_jiffies(timeout); - else - timeout_jiffies = MAX_SCHEDULE_TIMEOUT; - - ret = wait_for_completion_interruptible_timeout(&operation->completion, - timeout_jiffies); + ret = wait_for_completion_interruptible(&operation->completion); if (ret < 0) { /* Cancel the operation if interrupted */ gb_operation_cancel(operation, -ECANCELED); - } else if (ret == 0) { - /* Cancel the operation if op timed out */ - gb_operation_cancel(operation, -ETIMEDOUT); }
return gb_operation_result(operation); diff --git a/drivers/staging/greybus/operation.h b/drivers/staging/greybus/operation.h index de09a2c7de54..7529f01b2529 100644 --- a/drivers/staging/greybus/operation.h +++ b/drivers/staging/greybus/operation.h @@ -98,6 +98,7 @@ struct gb_operation { struct work_struct work; gb_operation_callback callback; struct completion completion; + struct timer_list timer;
struct kref kref; atomic_t waiters; @@ -164,6 +165,7 @@ bool gb_operation_response_alloc(struct gb_operation *operation,
int gb_operation_request_send(struct gb_operation *operation, gb_operation_callback callback, + unsigned int timeout, gfp_t gfp); int gb_operation_request_send_sync_timeout(struct gb_operation *operation, unsigned int timeout);