[PATCH net-next 03/10] net: ipa: increment backlog in replenish caller

From: Alex Elder
Date: Thu Feb 03 2022 - 12:09:56 EST


Three spots call ipa_endpoint_replenish(), and just one of those
requests that the backlog be incremented after completing the
replenish operation.

Instead, have the caller increment the backlog, and get rid of the
add_one argument to ipa_endpoint_replenish().

Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
---
drivers/net/ipa/ipa_endpoint.c | 29 +++++++++--------------------
1 file changed, 9 insertions(+), 20 deletions(-)

diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c
index f8dbd43949e16..060a025d70ec6 100644
--- a/drivers/net/ipa/ipa_endpoint.c
+++ b/drivers/net/ipa/ipa_endpoint.c
@@ -1084,7 +1084,6 @@ static int ipa_endpoint_replenish_one(struct ipa_endpoint *endpoint)
/**
* ipa_endpoint_replenish() - Replenish endpoint receive buffers
* @endpoint: Endpoint to be replenished
- * @add_one: Whether this is replacing a just-consumed buffer
*
* The IPA hardware can hold a fixed number of receive buffers for an RX
* endpoint, based on the number of entries in the underlying channel ring
@@ -1093,24 +1092,17 @@ static int ipa_endpoint_replenish_one(struct ipa_endpoint *endpoint)
* an endpoint can be disabled, in which case buffers are not queued to
* the hardware.
*/
-static void ipa_endpoint_replenish(struct ipa_endpoint *endpoint, bool add_one)
+static void ipa_endpoint_replenish(struct ipa_endpoint *endpoint)
{
struct gsi *gsi;
u32 backlog;
- int delta;

- if (!test_bit(IPA_REPLENISH_ENABLED, endpoint->replenish_flags)) {
- if (add_one)
- atomic_inc(&endpoint->replenish_backlog);
+ if (!test_bit(IPA_REPLENISH_ENABLED, endpoint->replenish_flags))
return;
- }

- /* If already active, just update the backlog */
- if (test_and_set_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags)) {
- if (add_one)
- atomic_inc(&endpoint->replenish_backlog);
+ /* Skip it if it's already active */
+ if (test_and_set_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags))
return;
- }

while (atomic_dec_not_zero(&endpoint->replenish_backlog))
if (ipa_endpoint_replenish_one(endpoint))
@@ -1118,17 +1110,13 @@ static void ipa_endpoint_replenish(struct ipa_endpoint *endpoint, bool add_one)

clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags);

- if (add_one)
- atomic_inc(&endpoint->replenish_backlog);
-
return;

try_again_later:
clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags);

/* The last one didn't succeed, so fix the backlog */
- delta = add_one ? 2 : 1;
- backlog = atomic_add_return(delta, &endpoint->replenish_backlog);
+ backlog = atomic_inc_return(&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
@@ -1152,7 +1140,7 @@ static void ipa_endpoint_replenish_enable(struct ipa_endpoint *endpoint)
/* Start replenishing if hardware currently has no buffers */
max_backlog = gsi_channel_tre_max(gsi, endpoint->channel_id);
if (atomic_read(&endpoint->replenish_backlog) == max_backlog)
- ipa_endpoint_replenish(endpoint, false);
+ ipa_endpoint_replenish(endpoint);
}

static void ipa_endpoint_replenish_disable(struct ipa_endpoint *endpoint)
@@ -1167,7 +1155,7 @@ static void ipa_endpoint_replenish_work(struct work_struct *work)

endpoint = container_of(dwork, struct ipa_endpoint, replenish_work);

- ipa_endpoint_replenish(endpoint, false);
+ ipa_endpoint_replenish(endpoint);
}

static void ipa_endpoint_skb_copy(struct ipa_endpoint *endpoint,
@@ -1372,7 +1360,8 @@ static void ipa_endpoint_rx_complete(struct ipa_endpoint *endpoint,
{
struct page *page;

- ipa_endpoint_replenish(endpoint, true);
+ ipa_endpoint_replenish(endpoint);
+ atomic_inc(&endpoint->replenish_backlog);

if (trans->cancelled)
return;
--
2.32.0