From: Paolo Abeni Date: Thu, 8 Feb 2024 18:03:49 +0000 (+0100) Subject: mptcp: drop the push_pending field X-Git-Tag: v6.7.6~192 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=427ef4ad502be5460aa5cfe87a7c021390481f26;p=thirdparty%2Fkernel%2Fstable.git mptcp: drop the push_pending field commit bdd70eb68913c960acb895b00a8c62eb64715b1f upstream. Such field is there to avoid acquiring the data lock in a few spots, but it adds complexity to the already non trivial locking schema. All the relevant call sites (mptcp-level re-injection, set socket options), are slow-path, drop such field in favor of 'cb_flags', adding the relevant locking. This patch could be seen as an improvement, instead of a fix. But it simplifies the next patch. The 'Fixes' tag has been added to help having this series backported to stable. Fixes: e9d09baca676 ("mptcp: avoid atomic bit manipulation when possible") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni Reviewed-by: Mat Martineau Signed-off-by: Matthieu Baerts (NGI0) Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 1ad94b3695408..5e7dfe69e1532 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1519,8 +1519,11 @@ static void mptcp_update_post_push(struct mptcp_sock *msk, void mptcp_check_and_set_pending(struct sock *sk) { - if (mptcp_send_head(sk)) - mptcp_sk(sk)->push_pending |= BIT(MPTCP_PUSH_PENDING); + if (mptcp_send_head(sk)) { + mptcp_data_lock(sk); + mptcp_sk(sk)->cb_flags |= BIT(MPTCP_PUSH_PENDING); + mptcp_data_unlock(sk); + } } static int __subflow_push_pending(struct sock *sk, struct sock *ssk, @@ -3138,7 +3141,6 @@ static int mptcp_disconnect(struct sock *sk, int flags) mptcp_destroy_common(msk, MPTCP_CF_FASTCLOSE); WRITE_ONCE(msk->flags, 0); msk->cb_flags = 0; - msk->push_pending = 0; msk->recovery = false; msk->can_ack = false; msk->fully_established = false; @@ -3364,8 +3366,7 @@ static void mptcp_release_cb(struct sock *sk) struct mptcp_sock *msk = mptcp_sk(sk); for (;;) { - unsigned long flags = (msk->cb_flags & MPTCP_FLAGS_PROCESS_CTX_NEED) | - msk->push_pending; + unsigned long flags = (msk->cb_flags & MPTCP_FLAGS_PROCESS_CTX_NEED); struct list_head join_list; if (!flags) @@ -3381,7 +3382,6 @@ static void mptcp_release_cb(struct sock *sk) * datapath acquires the msk socket spinlock while helding * the subflow socket lock */ - msk->push_pending = 0; msk->cb_flags &= ~flags; spin_unlock_bh(&sk->sk_lock.slock); diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index aa1a93fe40ffa..90265b865fb5a 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -286,7 +286,6 @@ struct mptcp_sock { int rmem_released; unsigned long flags; unsigned long cb_flags; - unsigned long push_pending; bool recovery; /* closing subflow write queue reinjected */ bool can_ack; bool fully_established;