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 C17ABC83F1F for ; Mon, 28 Aug 2023 10:39:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231672AbjH1Ki6 (ORCPT ); Mon, 28 Aug 2023 06:38:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58544 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231658AbjH1Ki0 (ORCPT ); Mon, 28 Aug 2023 06:38:26 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 167F6131 for ; Mon, 28 Aug 2023 03:38:20 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9FBE263F91 for ; Mon, 28 Aug 2023 10:38:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AEB7AC433CA; Mon, 28 Aug 2023 10:38:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1693219099; bh=ZIucK3oRjNS1SD2iAoSgDvO2XJ3s1uvgf5dOpYYZzeU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TKztHXTpa0U9NLbxzllkIxQ3S7fk3DZQDAp94Vxa5njkgcjOtD21aqZY8uxi96/9Q IzxhhtsjHvBAjCM3p39sQgUIaN2oGNzlQjTJE6uzHCO1nytUKWQNLeD+22kdjRUD37 GbZdUehRdssZVylljjObyDimtjAJhrBwKtFOT2Hs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Abel Wu , Shakeel Butt , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.4 073/158] sock: Fix misuse of sk_under_memory_pressure() Date: Mon, 28 Aug 2023 12:12:50 +0200 Message-ID: <20230828101159.744863359@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230828101157.322319621@linuxfoundation.org> References: <20230828101157.322319621@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Abel Wu [ Upstream commit 2d0c88e84e483982067a82073f6125490ddf3614 ] The status of global socket memory pressure is updated when: a) __sk_mem_raise_allocated(): enter: sk_memory_allocated(sk) > sysctl_mem[1] leave: sk_memory_allocated(sk) <= sysctl_mem[0] b) __sk_mem_reduce_allocated(): leave: sk_under_memory_pressure(sk) && sk_memory_allocated(sk) < sysctl_mem[0] So the conditions of leaving global pressure are inconstant, which may lead to the situation that one pressured net-memcg prevents the global pressure from being cleared when there is indeed no global pressure, thus the global constrains are still in effect unexpectedly on the other sockets. This patch fixes this by ignoring the net-memcg's pressure when deciding whether should leave global memory pressure. Fixes: e1aab161e013 ("socket: initial cgroup code.") Signed-off-by: Abel Wu Acked-by: Shakeel Butt Link: https://lore.kernel.org/r/20230816091226.1542-1-wuyun.abel@bytedance.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- include/net/sock.h | 6 ++++++ net/core/sock.c | 2 +- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/include/net/sock.h b/include/net/sock.h index ee8630d6abc16..61f5872aac24f 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1274,6 +1274,12 @@ static inline bool sk_has_memory_pressure(const struct sock *sk) return sk->sk_prot->memory_pressure != NULL; } +static inline bool sk_under_global_memory_pressure(const struct sock *sk) +{ + return sk->sk_prot->memory_pressure && + !!*sk->sk_prot->memory_pressure; +} + static inline bool sk_under_memory_pressure(const struct sock *sk) { if (!sk->sk_prot->memory_pressure) diff --git a/net/core/sock.c b/net/core/sock.c index 636427d400d7f..69b4158a29f74 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2631,7 +2631,7 @@ void __sk_mem_reduce_allocated(struct sock *sk, int amount) if (mem_cgroup_sockets_enabled && sk->sk_memcg) mem_cgroup_uncharge_skmem(sk->sk_memcg, amount); - if (sk_under_memory_pressure(sk) && + if (sk_under_global_memory_pressure(sk) && (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) sk_leave_memory_pressure(sk); } -- 2.40.1