From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 277CDC433FE for ; Mon, 20 Dec 2021 15:20:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239244AbhLTPUj (ORCPT ); Mon, 20 Dec 2021 10:20:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238599AbhLTPSj (ORCPT ); Mon, 20 Dec 2021 10:18:39 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62BF2C019D8B; Mon, 20 Dec 2021 06:59:37 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E270A6119E; Mon, 20 Dec 2021 14:59:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C54A1C36AE7; Mon, 20 Dec 2021 14:59:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1640012376; bh=WALEW7ISEHxknQeaXMMMR5mST5iAFqOYUjiAfuUwv4c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=x2vtoZLEcUedU+LkbHVFrQ3UK9tlVzz6fdekrcGC2f8OpDOAcfBFZYji3a/thUZj0 dv0FOBxhN0F6hnP3370XadLAB/8j6XYveVd8E+XNK7iEVIXq3QzoxscDkre1BWGP0t bK37vDIZyNOlPpLfdUrkPhHR8SbuIH7lxxKkZMzc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Magnus Karlsson , Daniel Borkmann Subject: [PATCH 5.15 172/177] Revert "xsk: Do not sleep in poll() when need_wakeup set" Date: Mon, 20 Dec 2021 15:35:22 +0100 Message-Id: <20211220143045.857712350@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211220143040.058287525@linuxfoundation.org> References: <20211220143040.058287525@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Magnus Karlsson commit 0706a78f31c4217ca144f630063ec9561a21548d upstream. This reverts commit bd0687c18e635b63233dc87f38058cd728802ab4. This patch causes a Tx only workload to go to sleep even when it does not have to, leading to misserable performance in skb mode. It fixed one rare problem but created a much worse one, so this need to be reverted while I try to craft a proper solution to the original problem. Fixes: bd0687c18e63 ("xsk: Do not sleep in poll() when need_wakeup set") Signed-off-by: Magnus Karlsson Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20211217145646.26449-1-magnus.karlsson@gmail.com Signed-off-by: Greg Kroah-Hartman --- net/xdp/xsk.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -692,6 +692,8 @@ static __poll_t xsk_poll(struct file *fi struct xdp_sock *xs = xdp_sk(sk); struct xsk_buff_pool *pool; + sock_poll_wait(file, sock, wait); + if (unlikely(!xsk_is_bound(xs))) return mask; @@ -703,8 +705,6 @@ static __poll_t xsk_poll(struct file *fi else /* Poll needs to drive Tx also in copy mode */ __xsk_sendmsg(sk); - } else { - sock_poll_wait(file, sock, wait); } if (xs->rx && !xskq_prod_is_empty(xs->rx))