Producer/Consumer: Refactor to use Queue policies

Previously the Producer and Consumer interfaces tracked the
Consumer and Producer respectively at the other end of the
queue that they interacted with.  This was done to avoid
modifying the queue implementation, but resulted in a rougher
interface that required additional initialization steps and
prevented alternative configurations; many producers and one
consumer for example.

This commit uses the new queue policies to track this
information.  The new direct policy behaves as the old producer
and consumers did.  Now the producers and consumers are just
named references to the queue that they work on and a convenient
location for a notification callback when the queue is updated in
a way that is relevent to the producer or consumer.

All users of Producer and Consumer have been updated including the
stream adaptors which are in use by the echo test code and the
mcdp28x0 driver.  Use of the stream adaptors has also been
simplified.

Signed-off-by: Anton Staaf <robotboy@chromium.org>

BRANCH=None
BUG=None
TEST=make buildall -j
     Manual testing of Ryu (P5) and discovery board echo task

Change-Id: I704be6378a31b4e20f5063295eff9943e4900409
Reviewed-on: https://chromium-review.googlesource.com/271792
Reviewed-by: Anton Staaf <robotboy@chromium.org>
Commit-Queue: Anton Staaf <robotboy@chromium.org>
Trybot-Ready: Anton Staaf <robotboy@chromium.org>
Tested-by: Anton Staaf <robotboy@chromium.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/common/queue_policies.c b/common/queue_policies.c
new file mode 100644
index 0000000000..130dee52f0
--- /dev/null
+++ b/common/queue_policies.c
@@ -0,0 +1,28 @@
+/* Copyright 2015 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Queue policies.
+ */
+#include "queue_policies.h"
+#include "util.h"
+
+#include <stddef.h>
+
+void queue_add_direct(struct queue_policy const *policy, size_t count)
+{
+	struct queue_policy_direct const *direct =
+		DOWNCAST(policy, struct queue_policy_direct, policy);
+
+	if (count && direct->consumer->ops->written)
+		direct->consumer->ops->written(direct->consumer, count);
+}
+
+void queue_remove_direct(struct queue_policy const *policy, size_t count)
+{
+	struct queue_policy_direct const *direct =
+		DOWNCAST(policy, struct queue_policy_direct, policy);
+
+	if (count && direct->producer->ops->read)
+		direct->producer->ops->read(direct->producer, count);
+}