From patchwork Mon Oct 14 20:55:43 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kuniyuki Iwashima X-Patchwork-Id: 835774 Received: from smtp-fw-80009.amazon.com (smtp-fw-80009.amazon.com [99.78.197.220]) (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 3C6961D1518 for ; Mon, 14 Oct 2024 20:56:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=99.78.197.220 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728939410; cv=none; b=jqzPvnSUk8QE8y8UrBKkQBk9WBl0jM9z0GXEi82ZYYXzPX+Powr6HAGX4A1XGilFKtgHoR30ytvbQxBI1/O8LwNMDO3LgL1ddnCh1MQE0s10rATYs6dhuA4mi5tt9ZJwaq06u3ovQvIOL7zH4oOrta3nzTzskE/uNlqqRsEgZ/o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728939410; c=relaxed/simple; bh=zoVxVHxBOoITHvYx/wds+4nlVcC3Cw40aNA88OH+CAs=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=gwy9zJT0KwraEqFVYEW1qtETonL4N4Qd49rLm2R/GZoLtLb3wZa0EFxp8z4cVvfcAZjz9d9jtCeJrYASi3ueDhYuW1cds7XH+nEic7gkKMLHBE9kj9YWL2kPF2aHflOxIn8K6mHLq3zDaahqIj+ZOugXsXmB2sOUtgIDWrWMNVI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com; spf=pass smtp.mailfrom=amazon.co.jp; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b=t8V+pgkW; arc=none smtp.client-ip=99.78.197.220 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=amazon.co.jp Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="t8V+pgkW" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1728939409; x=1760475409; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=cIC71K1ngjjnOWz/tQ2pY1RF/NWPWwSpvGOAjVKxY74=; b=t8V+pgkWsSXYvn36WzvBwNaqxX9D/4iG+f2+xmb8+SKdAMYcLsY1285N gyKNECj5PhB/NxSXKYir3tz7I0X562sOPH9Z/7RgbPPsqPwynBXfvxF+E wmIakueGeN/ykVtxKs3ij1rrZHlhKK1c//jnZYJokZa7sfPTsWX9sdF3f s=; X-IronPort-AV: E=Sophos;i="6.11,203,1725321600"; d="scan'208";a="138018246" Received: from pdx4-co-svc-p1-lb2-vlan2.amazon.com (HELO smtpout.prod.us-west-2.prod.farcaster.email.amazon.dev) ([10.25.36.210]) by smtp-border-fw-80009.pdx80.corp.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Oct 2024 20:56:47 +0000 Received: from EX19MTAUWA002.ant.amazon.com [10.0.21.151:43461] by smtpin.naws.us-west-2.prod.farcaster.email.amazon.dev [10.0.59.23:2525] with esmtp (Farcaster) id a1983923-8adc-4ffd-b998-fc6d6b098004; Mon, 14 Oct 2024 20:56:47 +0000 (UTC) X-Farcaster-Flow-ID: a1983923-8adc-4ffd-b998-fc6d6b098004 Received: from EX19D004ANA001.ant.amazon.com (10.37.240.138) by EX19MTAUWA002.ant.amazon.com (10.250.64.202) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1258.34; Mon, 14 Oct 2024 20:56:47 +0000 Received: from 6c7e67c6786f.amazon.com (10.106.101.44) by EX19D004ANA001.ant.amazon.com (10.37.240.138) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1258.35; Mon, 14 Oct 2024 20:56:44 +0000 From: Kuniyuki Iwashima To: Johannes Berg CC: Alexandre Ferrieux , Kuniyuki Iwashima , Kuniyuki Iwashima , Subject: [PATCH v1 wl-next 3/3] wifi: wext: Don't iterate all netns in wireless_nlevent_flush(). Date: Mon, 14 Oct 2024 13:55:43 -0700 Message-ID: <20241014205543.94787-4-kuniyu@amazon.com> X-Mailer: git-send-email 2.39.5 (Apple Git-154) In-Reply-To: <20241014205543.94787-1-kuniyu@amazon.com> References: <20241014205543.94787-1-kuniyu@amazon.com> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: EX19D045UWC001.ant.amazon.com (10.13.139.223) To EX19D004ANA001.ant.amazon.com (10.37.240.138) Commit 8bf862739a77 ("wext: fix message delay/ordering") introduced wext_netdev_notifier_call() to avoid message delay and out-of-order. The notifier calls wireless_nlevent_flush(), which iterates all netns. The problem is that this happens for any event and netdev, even if the host does not have a wext device. This is too noisy, especially on a host with thousands of netns as reported by Alexandre Ferrieux. Given that the wext event queue was implemented in struct net, wireless_nlevent_flush() does not need to iterate all netns. Let's avoid unnecessary netns iteration in wireless_nlevent_flush(). Reported-by: Alexandre Ferrieux Closes: https://lore.kernel.org/netdev/CAKYWH0Ti3=4GeeuVyWKJ9LyTuRnf3Wy9GKg4Jb7tdeaT39qADA@mail.gmail.com/ Signed-off-by: Kuniyuki Iwashima --- include/net/iw_handler.h | 4 ++-- net/wireless/core.c | 2 +- net/wireless/wext-core.c | 25 +++++++++++++------------ 3 files changed, 16 insertions(+), 15 deletions(-) diff --git a/include/net/iw_handler.h b/include/net/iw_handler.h index b80e474cb0aa..e6acff086d39 100644 --- a/include/net/iw_handler.h +++ b/include/net/iw_handler.h @@ -412,9 +412,9 @@ void wireless_send_event(struct net_device *dev, unsigned int cmd, union iwreq_data *wrqu, const char *extra); #ifdef CONFIG_WEXT_CORE /* flush all previous wext events - if work is done from netdev notifiers */ -void wireless_nlevent_flush(void); +void wireless_nlevent_flush(struct net *net); #else -static inline void wireless_nlevent_flush(void) {} +static inline void wireless_nlevent_flush(struct net *net) {} #endif /* We may need a function to send a stream of events to user space. diff --git a/net/wireless/core.c b/net/wireless/core.c index 4c8d8f167409..a864ec889de3 100644 --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -1629,7 +1629,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb, return NOTIFY_DONE; } - wireless_nlevent_flush(); + wireless_nlevent_flush(dev_net(dev)); return NOTIFY_OK; } diff --git a/net/wireless/wext-core.c b/net/wireless/wext-core.c index 4d7699135f46..28033211c9e3 100644 --- a/net/wireless/wext-core.c +++ b/net/wireless/wext-core.c @@ -345,6 +345,7 @@ static const int compat_event_type_size[] = { /* IW event code */ struct wext_net { + struct net *net; struct sk_buff_head nlevents; struct work_struct nlevent_work; }; @@ -356,26 +357,22 @@ static struct wext_net *wext_net(struct net *net) return net_generic(net, wext_net_id); } -void wireless_nlevent_flush(void) +void wireless_nlevent_flush(struct net *net) { + struct wext_net *wnet = wext_net(net); struct sk_buff *skb; - struct net *net; - down_read(&net_rwsem); - for_each_net(net) { - struct wext_net *wnet = wext_net(net); - while ((skb = skb_dequeue(&wnet->nlevents))) - rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, - GFP_KERNEL); - } - up_read(&net_rwsem); + while ((skb = skb_dequeue(&wnet->nlevents))) + rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_KERNEL); } EXPORT_SYMBOL_GPL(wireless_nlevent_flush); static int wext_netdev_notifier_call(struct notifier_block *nb, unsigned long state, void *ptr) { + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + /* * When a netdev changes state in any way, flush all pending messages * to avoid them going out in a strange order, e.g. RTM_NEWLINK after @@ -383,7 +380,7 @@ static int wext_netdev_notifier_call(struct notifier_block *nb, * or similar - all of which could otherwise happen due to delays from * schedule_work(). */ - wireless_nlevent_flush(); + wireless_nlevent_flush(dev_net(dev)); return NOTIFY_OK; } @@ -395,13 +392,17 @@ static struct notifier_block wext_netdev_notifier = { /* Process events generated by the wireless layer or the driver. */ static void wireless_nlevent_process(struct work_struct *work) { - wireless_nlevent_flush(); + struct wext_net *wnet; + + wnet = container_of(work, struct wext_net, nlevent_work); + wireless_nlevent_flush(wnet->net); } static int __net_init wext_pernet_init(struct net *net) { struct wext_net *wnet = wext_net(net); + wnet->net = net; skb_queue_head_init(&wnet->nlevents); INIT_WORK(&wnet->nlevent_work, wireless_nlevent_process);