net: ipa: kill replenish_backlog

We no longer use the replenish_backlog atomic variable to decide
when we've got work to do providing receive buffers to hardware.
Basically, we try to keep the hardware as full as possible, all the
time.  We keep supplying buffers until the hardware has no more
space for them.

As a result, we can get rid of the replenish_backlog field and the
atomic operations performed on it.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c
index b854a39c69925475e572ad43184e738d8db7b5f8..9d875126a360e7f4c823c9c423fae76e64a77d8c 100644 (file)
--- a/drivers/net/ipa/ipa_endpoint.c
+++ b/drivers/net/ipa/ipa_endpoint.c
@@ -1086,7 +1086,6 @@ static void ipa_endpoint_replenish(struct ipa_endpoint *endpoint)
                return;
 
        while ((trans = ipa_endpoint_trans_alloc(endpoint, 1))) {
-               WARN_ON(!atomic_dec_not_zero(&endpoint->replenish_backlog));
                if (ipa_endpoint_replenish_one(endpoint, trans))
                        goto try_again_later;
 
@@ -1105,9 +1104,6 @@ try_again_later:
        gsi_trans_free(trans);
        clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags);
 
-       /* The last one didn't succeed, so fix the backlog */
-       atomic_inc(&endpoint->replenish_backlog);
-
        /* Whenever a receive buffer transaction completes we'll try to
         * replenish again.  It's unlikely, but if we fail to supply even
         * one buffer, nothing will trigger another replenish attempt.
@@ -1346,7 +1342,6 @@ static void ipa_endpoint_rx_complete(struct ipa_endpoint *endpoint,
        struct page *page;
 
        ipa_endpoint_replenish(endpoint);
-       atomic_inc(&endpoint->replenish_backlog);
 
        if (trans->cancelled)
                return;
@@ -1693,8 +1688,6 @@ static void ipa_endpoint_setup_one(struct ipa_endpoint *endpoint)
                 */
                clear_bit(IPA_REPLENISH_ENABLED, endpoint->replenish_flags);
                clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags);
-               atomic_set(&endpoint->replenish_backlog,
-                          gsi_channel_tre_max(gsi, endpoint->channel_id));
                INIT_DELAYED_WORK(&endpoint->replenish_work,
                                  ipa_endpoint_replenish_work);
        }

diff --git a/drivers/net/ipa/ipa_endpoint.h b/drivers/net/ipa/ipa_endpoint.h
index c95816d882a74a2c59f7f4913f2f6f255a8e0c8b..9a37f9387f011137347e8e18aaabad2c6cd24d63 100644 (file)
--- a/drivers/net/ipa/ipa_endpoint.h
+++ b/drivers/net/ipa/ipa_endpoint.h
@@ -66,7 +66,6 @@ enum ipa_replenish_flag {
  * @netdev:            Network device pointer, if endpoint uses one
  * @replenish_flags:   Replenishing state flags
  * @replenish_ready:   Number of replenish transactions without doorbell
- * @replenish_backlog: Number of buffers needed to fill hardware queue
  * @replenish_work:    Work item used for repeated replenish failures
  */
 struct ipa_endpoint {
@@ -86,7 +85,6 @@ struct ipa_endpoint {
        /* Receive buffer replenishing for RX endpoints */
        DECLARE_BITMAP(replenish_flags, IPA_REPLENISH_COUNT);
        u32 replenish_ready;
-       atomic_t replenish_backlog;
        struct delayed_work replenish_work;             /* global wq */
 };