[PATCH 5.18 102/158] amt: remove unnecessary locks

From: Greg Kroah-Hartman
Date: Wed Jul 27 2022 - 13:44:51 EST


From: Taehee Yoo <ap420073@xxxxxxxxx>

[ Upstream commit 9c343ea6185febe5f6b74f7f7b3757f3dd9c5af6 ]

By the previous patch, amt gateway handlers are changed to worked by
a single thread.
So, most locks for gateway are not needed.
So, it removes.

Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface")
Signed-off-by: Taehee Yoo <ap420073@xxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/amt.c | 32 +++++---------------------------
1 file changed, 5 insertions(+), 27 deletions(-)

diff --git a/drivers/net/amt.c b/drivers/net/amt.c
index f8e8381e266b..615f26a553ae 100644
--- a/drivers/net/amt.c
+++ b/drivers/net/amt.c
@@ -577,8 +577,8 @@ static struct sk_buff *amt_build_igmp_gq(struct amt_dev *amt)
return skb;
}

-static void __amt_update_gw_status(struct amt_dev *amt, enum amt_status status,
- bool validate)
+static void amt_update_gw_status(struct amt_dev *amt, enum amt_status status,
+ bool validate)
{
if (validate && amt->status >= status)
return;
@@ -600,14 +600,6 @@ static void __amt_update_relay_status(struct amt_tunnel_list *tunnel,
tunnel->status = status;
}

-static void amt_update_gw_status(struct amt_dev *amt, enum amt_status status,
- bool validate)
-{
- spin_lock_bh(&amt->lock);
- __amt_update_gw_status(amt, status, validate);
- spin_unlock_bh(&amt->lock);
-}
-
static void amt_update_relay_status(struct amt_tunnel_list *tunnel,
enum amt_status status, bool validate)
{
@@ -700,9 +692,7 @@ static void amt_send_discovery(struct amt_dev *amt)
if (unlikely(net_xmit_eval(err)))
amt->dev->stats.tx_errors++;

- spin_lock_bh(&amt->lock);
- __amt_update_gw_status(amt, AMT_STATUS_SENT_DISCOVERY, true);
- spin_unlock_bh(&amt->lock);
+ amt_update_gw_status(amt, AMT_STATUS_SENT_DISCOVERY, true);
out:
rcu_read_unlock();
}
@@ -937,18 +927,14 @@ static void amt_secret_work(struct work_struct *work)

static void amt_event_send_discovery(struct amt_dev *amt)
{
- spin_lock_bh(&amt->lock);
if (amt->status > AMT_STATUS_SENT_DISCOVERY)
goto out;
get_random_bytes(&amt->nonce, sizeof(__be32));
- spin_unlock_bh(&amt->lock);

amt_send_discovery(amt);
- spin_lock_bh(&amt->lock);
out:
mod_delayed_work(amt_wq, &amt->discovery_wq,
msecs_to_jiffies(AMT_DISCOVERY_TIMEOUT));
- spin_unlock_bh(&amt->lock);
}

static void amt_discovery_work(struct work_struct *work)
@@ -966,7 +952,6 @@ static void amt_event_send_request(struct amt_dev *amt)
{
u32 exp;

- spin_lock_bh(&amt->lock);
if (amt->status < AMT_STATUS_RECEIVED_ADVERTISEMENT)
goto out;

@@ -976,21 +961,18 @@ static void amt_event_send_request(struct amt_dev *amt)
amt->ready4 = false;
amt->ready6 = false;
amt->remote_ip = 0;
- __amt_update_gw_status(amt, AMT_STATUS_INIT, false);
+ amt_update_gw_status(amt, AMT_STATUS_INIT, false);
amt->req_cnt = 0;
goto out;
}
- spin_unlock_bh(&amt->lock);

amt_send_request(amt, false);
amt_send_request(amt, true);
- spin_lock_bh(&amt->lock);
- __amt_update_gw_status(amt, AMT_STATUS_SENT_REQUEST, true);
+ amt_update_gw_status(amt, AMT_STATUS_SENT_REQUEST, true);
amt->req_cnt++;
out:
exp = min_t(u32, (1 * (1 << amt->req_cnt)), AMT_MAX_REQ_TIMEOUT);
mod_delayed_work(amt_wq, &amt->req_wq, msecs_to_jiffies(exp * 1000));
- spin_unlock_bh(&amt->lock);
}

static void amt_req_work(struct work_struct *work)
@@ -2386,12 +2368,10 @@ static bool amt_membership_query_handler(struct amt_dev *amt,
ihv3 = skb_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS);
skb_reset_transport_header(skb);
skb_push(skb, sizeof(*iph) + AMT_IPHDR_OPTS);
- spin_lock_bh(&amt->lock);
amt->ready4 = true;
amt->mac = amtmq->response_mac;
amt->req_cnt = 0;
amt->qi = ihv3->qqic;
- spin_unlock_bh(&amt->lock);
skb->protocol = htons(ETH_P_IP);
eth->h_proto = htons(ETH_P_IP);
ip_eth_mc_map(iph->daddr, eth->h_dest);
@@ -2411,12 +2391,10 @@ static bool amt_membership_query_handler(struct amt_dev *amt,
mld2q = skb_pull(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS);
skb_reset_transport_header(skb);
skb_push(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS);
- spin_lock_bh(&amt->lock);
amt->ready6 = true;
amt->mac = amtmq->response_mac;
amt->req_cnt = 0;
amt->qi = mld2q->mld2q_qqic;
- spin_unlock_bh(&amt->lock);
skb->protocol = htons(ETH_P_IPV6);
eth->h_proto = htons(ETH_P_IPV6);
ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
--
2.35.1