From patchwork Mon Apr 14 16:07:51 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 14050690 X-Patchwork-Delegate: kuba@kernel.org Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 029F7288C89 for ; Mon, 14 Apr 2025 16:08:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744646900; cv=none; b=EGdsg5MiXVPo5//07N7dJdz+eyKsSOvx6KVaPbOrNz2z9yELsowzjlYiVzSL/i7USc4PKGfhOtEDfst/7Xkp9Ie9vLDlkr254k2fJVlNhrCYUl6WgVpj9wl12YqIKBKagubLNYI794846FmULcpbGdnrTGvwlhQfNOf9aCEUNMI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744646900; c=relaxed/simple; bh=VXleKi/U/kMgP7jABQMiZxQCqP98FQpEysCuzMoNYOk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bPW7qyc8UGSHAmRU/4IRbRWA6DO9ocLvjl0hOc/xqXB2bS8lfB38so1ztAMTZRrwL/krMqFnEUprw8efFbdNcRIiDKuIq8IgIRAP/hYY8dZ0alaM7Gmq17KSBuQH/yn+zMVtY9bL7Sw0VrCgZYBAHFlG2cRzA2IZ1j3/bBZY604= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=A4btqFw1; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=SQlwiqz3; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="A4btqFw1"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="SQlwiqz3" From: Sebastian Andrzej Siewior DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1744646894; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qqlT1nY5GZsGQPH1WnHjRykG1pCxKAGysrL3Y4gboDY=; b=A4btqFw1KJRKMgA//iPQ2lSLtXHxDhLxKddQFKfGMck/CV00tCkRjTOfQ3v8RaMOJ1XEKN 48vH7AIoHs42bYSLn7yq0T5jPEWcj0K/KQVQbwsbTGjwgkj4Ndb996RPXi9nqpv7A1VPUk GPCv1PPSWzVyW3KMpXrvk1WM6w4aF3GWWNIoRLESy9VKO5HvCQ8SemmIlZRIJNVd2frdeI tAbEjNsByqGOLna5zFAZtKBV8hpaPxZ6JlbMrtwbb9NemHxiIWxUbvT68BKkYPfHaUibZf 5Um5FVvbq/zXHIcU1RBypdwI7o/823+7xN7P+IGyw+gu1OOFpb9lhe1vSHVFgw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1744646894; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qqlT1nY5GZsGQPH1WnHjRykG1pCxKAGysrL3Y4gboDY=; b=SQlwiqz3R7oKpmeWQF5x5Y45PppgcM2ywQuRcopP29s0xrNdA89Vfo+dquqwoCsTU1X2Ut dV865SCjPje6XuBQ== To: netdev@vger.kernel.org, linux-rt-devel@lists.linux.dev Cc: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Thomas Gleixner , Sebastian Andrzej Siewior , Matthieu Baerts , Mat Martineau , Geliang Tang , mptcp@lists.linux.dev Subject: [PATCH net-next v2 15/18] mptcp: Use nested-BH locking for hmac_storage Date: Mon, 14 Apr 2025 18:07:51 +0200 Message-ID: <20250414160754.503321-16-bigeasy@linutronix.de> In-Reply-To: <20250414160754.503321-1-bigeasy@linutronix.de> References: <20250414160754.503321-1-bigeasy@linutronix.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org mptcp_delegated_actions is a per-CPU variable and relies on disabled BH for its locking. Without per-CPU locking in local_bh_disable() on PREEMPT_RT this data structure requires explicit locking. Add a local_lock_t to the data structure and use local_lock_nested_bh() for locking. This change adds only lockdep coverage and does not alter the functional behaviour for !PREEMPT_RT. Cc: Matthieu Baerts Cc: Mat Martineau Cc: Geliang Tang Cc: mptcp@lists.linux.dev Signed-off-by: Sebastian Andrzej Siewior --- net/mptcp/protocol.c | 4 +++- net/mptcp/protocol.h | 9 ++++++++- 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 44f7ab463d755..b6cb93a3f9a2d 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -46,7 +46,9 @@ 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); -DEFINE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); +DEFINE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions) = { + .bh_lock = INIT_LOCAL_LOCK(bh_lock), +}; static struct net_device *mptcp_napi_dev; /* Returns end sequence number of the receiver's advertised window */ diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index d409586b5977f..88cc2a857adce 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -479,6 +479,7 @@ mptcp_subflow_rsk(const struct request_sock *rsk) struct mptcp_delegated_action { struct napi_struct napi; + local_lock_t bh_lock; struct list_head head; }; @@ -670,9 +671,11 @@ static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node))) return; + local_lock_nested_bh(&mptcp_delegated_actions.bh_lock); delegated = this_cpu_ptr(&mptcp_delegated_actions); schedule = list_empty(&delegated->head); list_add_tail(&subflow->delegated_node, &delegated->head); + local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock); sock_hold(mptcp_subflow_tcp_sock(subflow)); if (schedule) napi_schedule(&delegated->napi); @@ -684,11 +687,15 @@ mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) { struct mptcp_subflow_context *ret; - if (list_empty(&delegated->head)) + local_lock_nested_bh(&mptcp_delegated_actions.bh_lock); + if (list_empty(&delegated->head)) { + local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock); return NULL; + } ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); list_del_init(&ret->delegated_node); + local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock); return ret; }