mmc: queue: Fix queue thread wake-up

The only time the driver sleeps expecting to be woken upon the arrival of
a new request, is when the dispatch queue is empty. The only time that it
is known whether the dispatch queue is empty is after NULL is returned
from blk_fetch_request() while under the queue lock.

Recognizing those facts, simplify the synchronization between the queue
thread and the request function. A couple of flags tell the request
function what to do, and the queue lock and barriers associated with
wake-ups ensure synchronization.

The result is simpler and allows the removal of the context_info lock.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Harjani Ritesh <riteshh@codeaurora.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

1 files changed, 0 insertions, 2 deletions

diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 2ce32fefb41c..8bc884121465 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -197,14 +197,12 @@ struct mmc_slot {
  * @is_new_req		wake up reason was new request
  * @is_waiting_last_req	mmc context waiting for single running request
  * @wait		wait queue
- * @lock		lock to protect data fields
  */
 struct mmc_context_info {
 	bool			is_done_rcv;
 	bool			is_new_req;
 	bool			is_waiting_last_req;
 	wait_queue_head_t	wait;
-	spinlock_t		lock;
 };
 
 struct regulator;