* [PATCH mptcp-next v2 1/2] mptcp: add use_lock for mptcp_retrans
2022-12-06 13:30 [PATCH mptcp-next v2 0/2] BPF redundant scheduler, part 3 Geliang Tang
@ 2022-12-06 13:30 ` Geliang Tang
2022-12-06 13:30 ` [PATCH mptcp-next v2 2/2] mptcp: retrans for redundant sends Geliang Tang
1 sibling, 0 replies; 3+ messages in thread
From: Geliang Tang @ 2022-12-06 13:30 UTC (permalink / raw)
To: mptcp; +Cc: Geliang Tang
This patch adds a new parameter named 'ues_lock' for __mptcp_retrans()
to set whether to use socket locks in this function.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
net/mptcp/protocol.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 5505c1439b3e..9f0237b5a4b4 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -2523,7 +2523,7 @@ static void mptcp_check_fastclose(struct mptcp_sock *msk)
sk_error_report(sk);
}
-static void __mptcp_retrans(struct sock *sk)
+static void __mptcp_retrans(struct sock *sk, bool use_lock)
{
struct mptcp_sock *msk = mptcp_sk(sk);
struct mptcp_subflow_context *subflow;
@@ -2566,7 +2566,8 @@ static void __mptcp_retrans(struct sock *sk)
ssk = mptcp_subflow_tcp_sock(subflow);
- lock_sock(ssk);
+ if (use_lock)
+ lock_sock(ssk);
/* limit retransmission to the bytes already sent on some subflows */
info.sent = 0;
@@ -2588,7 +2589,8 @@ static void __mptcp_retrans(struct sock *sk)
WRITE_ONCE(msk->allow_infinite_fallback, false);
}
- release_sock(ssk);
+ if (use_lock)
+ release_sock(ssk);
msk->last_snd = ssk;
}
@@ -2694,7 +2696,7 @@ static void mptcp_worker(struct work_struct *work)
__mptcp_close_subflow(msk);
if (test_and_clear_bit(MPTCP_WORK_RTX, &msk->flags))
- __mptcp_retrans(sk);
+ __mptcp_retrans(sk, true);
fail_tout = msk->first ? READ_ONCE(mptcp_subflow_ctx(msk->first)->fail_tout) : 0;
if (fail_tout && time_after(jiffies, fail_tout))
@@ -3308,7 +3310,7 @@ static void mptcp_release_cb(struct sock *sk)
if (flags & BIT(MPTCP_PUSH_PENDING))
__mptcp_push_pending(sk, 0);
if (flags & BIT(MPTCP_RETRANSMIT))
- __mptcp_retrans(sk);
+ __mptcp_retrans(sk, true);
cond_resched();
spin_lock_bh(&sk->sk_lock.slock);
--
2.35.3
^ permalink raw reply related [flat|nested] 3+ messages in thread* [PATCH mptcp-next v2 2/2] mptcp: retrans for redundant sends
2022-12-06 13:30 [PATCH mptcp-next v2 0/2] BPF redundant scheduler, part 3 Geliang Tang
2022-12-06 13:30 ` [PATCH mptcp-next v2 1/2] mptcp: add use_lock for mptcp_retrans Geliang Tang
@ 2022-12-06 13:30 ` Geliang Tang
1 sibling, 0 replies; 3+ messages in thread
From: Geliang Tang @ 2022-12-06 13:30 UTC (permalink / raw)
To: mptcp; +Cc: Geliang Tang
Redundant sends need to work more like the MPTCP retransmit code path.
When the scheduler selects multiple subflows, the first subflow to send
is a "normal" transmit, and any other subflows would act like a retransmit
when accessing the dfrags.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
net/mptcp/protocol.c | 39 ++++++++++++++++++++++++++++++++++-----
1 file changed, 34 insertions(+), 5 deletions(-)
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 9f0237b5a4b4..a8cb12af1d51 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -45,6 +45,7 @@ static struct percpu_counter mptcp_sockets_allocated ____cacheline_aligned_in_sm
static void __mptcp_destroy_sock(struct sock *sk);
static void __mptcp_check_send_data_fin(struct sock *sk);
+static void __mptcp_retrans(struct sock *sk, bool use_lock);
DEFINE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions);
static struct net_device mptcp_napi_dev;
@@ -998,7 +999,7 @@ static void __mptcp_clean_una(struct sock *sk)
if (unlikely(dfrag == msk->first_pending)) {
/* in recovery mode can see ack after the current snd head */
- if (WARN_ON_ONCE(!msk->recovery))
+ if (!msk->recovery)
break;
WRITE_ONCE(msk->first_pending, mptcp_send_next(sk));
@@ -1013,7 +1014,7 @@ static void __mptcp_clean_una(struct sock *sk)
/* prevent wrap around in recovery mode */
if (unlikely(delta > dfrag->already_sent)) {
- if (WARN_ON_ONCE(!msk->recovery))
+ if (!msk->recovery)
goto out;
if (WARN_ON_ONCE(delta > dfrag->data_len))
goto out;
@@ -1473,7 +1474,8 @@ struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk)
static void mptcp_push_release(struct sock *ssk, struct mptcp_sendmsg_info *info)
{
- tcp_push(ssk, 0, info->mss_now, tcp_sk(ssk)->nonagle, info->size_goal);
+ if (info->mss_now)
+ tcp_push(ssk, 0, info->mss_now, tcp_sk(ssk)->nonagle, info->size_goal);
release_sock(ssk);
}
@@ -1559,10 +1561,15 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
.flags = flags,
};
bool do_check_data_fin = false;
+ struct mptcp_data_frag *head;
int push_count = 1;
+ head = mptcp_send_head(sk);
+ if (!head)
+ goto out;
+
while (mptcp_send_head(sk) && (push_count > 0)) {
- int ret = 0;
+ int ret = 0, i = 0;
if (mptcp_sched_get_send(msk))
break;
@@ -1571,6 +1578,13 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
mptcp_for_each_subflow(msk, subflow) {
if (READ_ONCE(subflow->scheduled)) {
+ if (i > 0) {
+ WRITE_ONCE(msk->first_pending, head);
+ mptcp_push_release(ssk, &info);
+ __mptcp_retrans(sk, true);
+ goto out;
+ }
+
mptcp_subflow_set_scheduled(subflow, false);
prev_ssk = ssk;
@@ -1599,6 +1613,7 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
push_count--;
continue;
}
+ i++;
do_check_data_fin = true;
msk->last_snd = ssk;
}
@@ -1609,6 +1624,7 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
if (ssk)
mptcp_push_release(ssk, &info);
+out:
/* ensure the rtx timer is running */
if (!mptcp_timer_pending(sk))
mptcp_reset_timer(sk);
@@ -1623,14 +1639,19 @@ static void __mptcp_subflow_push_pending(struct sock *sk, struct sock *ssk, bool
struct mptcp_sendmsg_info info = {
.data_lock_held = true,
};
+ struct mptcp_data_frag *head;
struct sock *xmit_ssk;
bool push = true;
int copied = 0;
+ head = mptcp_send_head(sk);
+ if (!head)
+ goto out;
+
info.flags = 0;
while (mptcp_send_head(sk) && push) {
bool delegate = false;
- int ret = 0;
+ int ret = 0, i = 0;
/* check for a different subflow usage only after
* spooling the first chunk of data
@@ -1650,6 +1671,12 @@ static void __mptcp_subflow_push_pending(struct sock *sk, struct sock *ssk, bool
mptcp_for_each_subflow(msk, subflow) {
if (READ_ONCE(subflow->scheduled)) {
+ if (i > 0) {
+ WRITE_ONCE(msk->first_pending, head);
+ __mptcp_retrans(sk, false);
+ goto out;
+ }
+
mptcp_subflow_set_scheduled(subflow, false);
xmit_ssk = mptcp_subflow_tcp_sock(subflow);
@@ -1660,6 +1687,7 @@ static void __mptcp_subflow_push_pending(struct sock *sk, struct sock *ssk, bool
goto out;
mptcp_subflow_delegate(subflow,
MPTCP_DELEGATE_SEND);
+ i++;
msk->last_snd = ssk;
delegate = true;
push = false;
@@ -1671,6 +1699,7 @@ static void __mptcp_subflow_push_pending(struct sock *sk, struct sock *ssk, bool
push = false;
continue;
}
+ i++;
copied += ret;
msk->last_snd = ssk;
}
--
2.35.3
^ permalink raw reply related [flat|nested] 3+ messages in thread