diff mbox series

[mptcp-next,v3,04/10] mptcp: pm: add subflow_established() interface

Message ID 0851219a7e333127fc1dbd927c5a8bd5f11efcc5.1742521397.git.tanggeliang@kylinos.cn (mailing list archive)
State Superseded, archived
Delegated to: Matthieu Baerts
Headers show
Series BPF path manager, part 6 | expand

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Context Check Description
matttbe/checkpatch success total: 0 errors, 0 warnings, 0 checks, 73 lines checked
matttbe/shellcheck success MPTCP selftests files have not been modified
matttbe/build success Build and static analysis OK
matttbe/KVM_Validation__normal success Success! ✅
matttbe/KVM_Validation__debug success Success! ✅
matttbe/KVM_Validation__btf-normal__only_bpftest_all_ success Success! ✅
matttbe/KVM_Validation__btf-debug__only_bpftest_all_ success Success! ✅

Commit Message

Geliang Tang March 21, 2025, 1:44 a.m. UTC 
From: Geliang Tang <tanggeliang@kylinos.cn>

This patch adds a .subflow_established interface for struct mptcp_pm_ops,
and calls pm->ops->subflow_established in from mptcp_pm_worker(). Then
get rid of the corresponding code from __mptcp_pm_kernel_worker().

Since mptcp_pm_addr_send_ack() is a sleepable kfunc, which is invoked
by mptcp_pm_create_subflow_or_signal_addr(), .subflow_established()
interface of BPF PM should be invoked by __bpf_prog_enter_sleepable(),
which can't be invoked under a lock. This patch unlocks the pm lock
before invoking this interface in mptcp_pm_worker(), while holding this
lock in mptcp_pm_kernel_subflow_established().

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 include/net/mptcp.h   |  1 +
 net/mptcp/pm.c        | 13 +++++++++++--
 net/mptcp/pm_kernel.c |  9 ++++-----
 3 files changed, 16 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/include/net/mptcp.h b/include/net/mptcp.h
index d7410f08399e..4ac936e4ce0d 100644
--- a/include/net/mptcp.h
+++ b/include/net/mptcp.h
@@ -126,6 +126,7 @@  struct mptcp_pm_ops {
 
 	/* optional */
 	void (*established)(struct mptcp_sock *msk);
+	void (*subflow_established)(struct mptcp_sock *msk);
 
 	char			name[MPTCP_PM_NAME_MAX];
 	struct module		*owner;
diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index a121c08b456e..35361d525101 100644
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -544,7 +544,7 @@  void mptcp_pm_subflow_established(struct mptcp_sock *msk)
 
 	pr_debug("msk=%p\n", msk);
 
-	if (!READ_ONCE(pm->work_pending))
+	if (!READ_ONCE(pm->work_pending) || !pm->ops->subflow_established)
 		return;
 
 	spin_lock_bh(&pm->lock);
@@ -571,6 +571,9 @@  void mptcp_pm_subflow_check_next(struct mptcp_sock *msk,
 		return;
 	}
 
+	if (!pm->ops->subflow_established)
+		return;
+
 	if (!READ_ONCE(pm->work_pending) && !update_subflows)
 		return;
 
@@ -633,7 +636,7 @@  void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
 
 	pr_debug("msk=%p\n", msk);
 
-	if (!READ_ONCE(pm->work_pending))
+	if (!READ_ONCE(pm->work_pending) || !pm->ops->subflow_established)
 		return;
 
 	spin_lock_bh(&pm->lock);
@@ -971,6 +974,12 @@  void mptcp_pm_worker(struct mptcp_sock *msk)
 		pm->ops->established(msk);
 		spin_lock_bh(&pm->lock);
 	}
+	if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
+		pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
+		spin_unlock_bh(&pm->lock);
+		pm->ops->subflow_established(msk);
+		spin_lock_bh(&pm->lock);
+	}
 	__mptcp_pm_kernel_worker(msk);
 
 	spin_unlock_bh(&msk->pm.lock);
diff --git a/net/mptcp/pm_kernel.c b/net/mptcp/pm_kernel.c
index 6d30d5958f0e..bd17b1afee2c 100644
--- a/net/mptcp/pm_kernel.c
+++ b/net/mptcp/pm_kernel.c
@@ -374,9 +374,11 @@  static void mptcp_pm_kernel_established(struct mptcp_sock *msk)
 	spin_unlock_bh(&msk->pm.lock);
 }
 
-static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk)
+static void mptcp_pm_kernel_subflow_established(struct mptcp_sock *msk)
 {
+	spin_lock_bh(&msk->pm.lock);
 	mptcp_pm_create_subflow_or_signal_addr(msk);
+	spin_unlock_bh(&msk->pm.lock);
 }
 
 /* Fill all the local addresses into the array addrs[],
@@ -1350,10 +1352,6 @@  void __mptcp_pm_kernel_worker(struct mptcp_sock *msk)
 		pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED);
 		mptcp_pm_nl_add_addr_received(msk);
 	}
-	if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
-		pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
-		mptcp_pm_nl_subflow_established(msk);
-	}
 }
 
 static int __net_init pm_nl_init_net(struct net *net)
@@ -1421,6 +1419,7 @@  struct mptcp_pm_ops mptcp_pm_kernel = {
 	.get_local_id		= mptcp_pm_kernel_get_local_id,
 	.get_priority		= mptcp_pm_kernel_get_priority,
 	.established		= mptcp_pm_kernel_established,
+	.subflow_established	= mptcp_pm_kernel_subflow_established,
 	.init			= mptcp_pm_kernel_init,
 	.name			= "kernel",
 	.owner			= THIS_MODULE,