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 D747EEE49B6 for ; Thu, 24 Aug 2023 15:04:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242060AbjHXPDt (ORCPT ); Thu, 24 Aug 2023 11:03:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54382 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242123AbjHXPDb (ORCPT ); Thu, 24 Aug 2023 11:03:31 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC95C1BD9 for ; Thu, 24 Aug 2023 08:03:17 -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 BBC06671A1 for ; Thu, 24 Aug 2023 15:03:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CCE4EC433C7; Thu, 24 Aug 2023 15:03:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1692889397; bh=wx+HxgQNOJajXthNIzHsTKh/AY8ani5R2DHWD5DhKiQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EkIcGxBwkfDWfFGZB70YSWnPzB6bzr6DbqZh7oGe4HlPfQJbdYKYZvFgpRcdjuQ1W 53z3z9A+dvBw2p8TnpkDMGlJmVlehvw3eaz5Lz0T+lJCwq9lrgBzZTFLEPJoB0+ALi cv34OO0i9kICW6fyoTFKha/jCUKoJxnqtYMe/79s= 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 5.10 092/135] sock: Fix misuse of sk_under_memory_pressure() Date: Thu, 24 Aug 2023 16:50:35 +0200 Message-ID: <20230824145030.894984496@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230824145027.008282920@linuxfoundation.org> References: <20230824145027.008282920@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 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 1fb5c535537c1..665e388593752 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1346,6 +1346,12 @@ 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 98f4b4a80de42..742356cfd07c4 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2724,7 +2724,7 @@ 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