From patchwork Thu Nov 7 15:57:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Breno Leitao X-Patchwork-Id: 13866656 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-ej1-f44.google.com (mail-ej1-f44.google.com [209.85.218.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A1CEA215C73; Thu, 7 Nov 2024 15:57:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.44 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730995042; cv=none; b=ElxX38etUUep2ep2BAHiHmHUsstBkm12XPo3xld4St7MT0uBdQnwReX84xH4V78qh4tmkCKYesvLOHK8BTFwRNCo/GrTRs3TgUC0uOnxX11GxlGj8WnvYiHsc1h81UIYbIIRmybUUDAWnkIzPq3zjnO/o6VqpbiO/qobdNxl35E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730995042; c=relaxed/simple; bh=O6G3z98wXMU2YHskw+iWUsDZqJS9nuyfK8uqaz/Y0D4=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=PrM37apsp0grTUOk5TuTi2O+nJUJmqseaApV3j3MYDQ0zHwElB3Pv0Yd0YQx3KcqRd1u2sxVEbmwvpfbwGLko95Kla/lqatOSesDKx0gSPthEs11+gtADVCtxrHEPLhVxB9AP4xDMkYRJ8wvov2yfuw8RvusxuzS6El6udYWMso= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=debian.org; spf=pass smtp.mailfrom=gmail.com; arc=none smtp.client-ip=209.85.218.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-ej1-f44.google.com with SMTP id a640c23a62f3a-a99f1fd20c4so157879566b.0; Thu, 07 Nov 2024 07:57:20 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1730995038; x=1731599838; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=IqS89/NeNKi4uydQWItWI4zKvSn/L7HP4SPCkznjfEg=; b=Ir5k2JdPzAIewW5ggXfQiPw+A9VHI/kDcsWQ2l6K3uz7K1ajW4lsbPtNTc0rcDekUj FuDJTaOZdeQQP6yHtZOI64CwCux2IJJoEFNWasylq9D5LMH8S4cRCUNQwom7q7tbm5hM O6vjyVi8PGeTs8Aqo2YrAZtWqDaaHrrlnCBWCp+1DT46H+hpxtNEFCmlj3h00WN4jIzH zD8gm33tL9AJXRMYpxx6iJXKzJv9pIumRo0XYaIrm/EA2lKlDtc2Gmt8obZZ2Y4gXM+t scOwM08j75BMwZpr3Uk84qEjif93gFHApX1KcNRBLINYQFXdSLtXPN4hopOEgyYeuc8B cPcw== X-Forwarded-Encrypted: i=1; AJvYcCXSwFSSk5IVhFLPGz0yBWp/N9n9dBqsvz2DdrnOcJdFvpYBoTjnClO2vDksznopXE8khDNm78qlQKalNbI=@vger.kernel.org X-Gm-Message-State: AOJu0Yy6QmEvzA5e7lu2N63Cn7hDqVZQUmtJfk+lf077aKaXc0Bg6I1K 2N6gLadnL1qBoPLghd+HgVC1galSnHf9bDxOj6sYI4mzjaO9auTgouUkHA== X-Google-Smtp-Source: AGHT+IFZsXP79pPfpJZ4CyW5PRH8wvT1NzyJot5WN9TK02OPh2rk1OeSeDDBjvHvwRHy2R4aGqRH4Q== X-Received: by 2002:a17:907:d0c:b0:a99:fb56:39cc with SMTP id a640c23a62f3a-a9eeafc8be9mr48057866b.38.1730995038081; Thu, 07 Nov 2024 07:57:18 -0800 (PST) Received: from localhost (fwdproxy-lla-116.fbsv.net. [2a03:2880:30ff:74::face:b00c]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a9ee0e0faaesm107761666b.175.2024.11.07.07.57.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Nov 2024 07:57:17 -0800 (PST) From: Breno Leitao Date: Thu, 07 Nov 2024 07:57:07 -0800 Subject: [PATCH net-next v2 2/2] net: netpoll: flush skb pool during cleanup Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241107-skb_buffers_v2-v2-2-288c6264ba4f@debian.org> References: <20241107-skb_buffers_v2-v2-0-288c6264ba4f@debian.org> In-Reply-To: <20241107-skb_buffers_v2-v2-0-288c6264ba4f@debian.org> To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Breno Leitao X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=1806; i=leitao@debian.org; h=from:subject:message-id; bh=O6G3z98wXMU2YHskw+iWUsDZqJS9nuyfK8uqaz/Y0D4=; b=owEBbQKS/ZANAwAIATWjk5/8eHdtAcsmYgBnLONZV4J75wiXQl5WtSLzAYYRB+uRtpMLkAIcC NUfli+1ivOJAjMEAAEIAB0WIQSshTmm6PRnAspKQ5s1o5Of/Hh3bQUCZyzjWQAKCRA1o5Of/Hh3 bd1BD/9/rVU0n1pYI4bVOAX3Nfg3FE+c7qVkbcY3wGSSAj5h2aPYGM6NL/zBw1bjIxGiG6Z6j5e t/XxJMEk8Y+HqipaV0uj4yjl2aYXT0S6RHkrh69b4fotmzTtRzct6bbD1tqUGU9RVZeOaq8z4UG hvd3s1ypGU/94F6PkticqmdUDUdvlIE8wimHSl7FLtlavSvSt0ys0y6NFgNyRKn70ON3orbBc2V q50UMc7qfYIWsNll281x3f8lm0gCFLqjALrQpytx4FID+y2SRMxz85q8ePkOdKY9bGoEtPTbTa3 s2SVSEE73DkgFgkJOzUnpeEJYpjkRLhBIZz2hwW5GD7fxskv4vMnSmrm9hL6XOELU/g1oFPJDRi 7Wp+UM6a7fCV7XGkZAIDf+22Df29M+RyJVvFGyZrozBA8yvuxunBeLQGmRo+LVFQ4wq/ORgXu7G HmGTOC5/41SFxfP0qRcH3Ows4QVniQpInCdLyvQ9Ao3Oete+ShN5m+ZK+NztxDCHi07jcnFwCKI rhIQ0rs5KSPHBtmBBwkRNgzaSH1B6rSYa99klzGK6H4KYv4mln62Hr0TLmkPO3p6BOAWq1ftKGP Q1/talQ+ckI+SASkT2vI1C5nydrotzSmHx8cD0oy4OZa/ka4h4tmpxt6rc0Xps/rBIxHoONLgW4 PGsB7Ikpn+Z1aNA== X-Developer-Key: i=leitao@debian.org; a=openpgp; fpr=AC8539A6E8F46702CA4A439B35A3939FFC78776D X-Patchwork-Delegate: kuba@kernel.org The netpoll subsystem maintains a pool of 32 pre-allocated SKBs per instance, but these SKBs are not freed when the netpoll user is brought down. This leads to memory waste as these buffers remain allocated but unused. Add skb_pool_flush() to properly clean up these SKBs when netconsole is terminated, improving memory efficiency. Signed-off-by: Breno Leitao --- net/core/netpoll.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 719c9aae845fbeb6f5b53a2bef675d3cb8cd44a7..498cc38073a3dc9f829f74f254bc70b26ef3856c 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -531,6 +531,22 @@ static int netpoll_parse_ip_addr(const char *str, union inet_addr *addr) return -1; } +static void skb_pool_flush(struct netpoll *np) +{ + struct sk_buff_head *skb_pool; + struct sk_buff *skb; + unsigned long flags; + + skb_pool = &np->skb_pool; + + spin_lock_irqsave(&skb_pool->lock, flags); + while (skb_pool->qlen > 0) { + skb = __skb_dequeue(skb_pool); + kfree_skb(skb); + } + spin_unlock_irqrestore(&skb_pool->lock, flags); +} + int netpoll_parse_options(struct netpoll *np, char *opt) { char *cur=opt, *delim; @@ -779,10 +795,12 @@ int netpoll_setup(struct netpoll *np) err = __netpoll_setup(np, ndev); if (err) - goto put; + goto flush; rtnl_unlock(); return 0; +flush: + skb_pool_flush(np); put: DEBUG_NET_WARN_ON_ONCE(np->dev); if (ip_overwritten) @@ -830,6 +848,8 @@ void __netpoll_cleanup(struct netpoll *np) call_rcu(&npinfo->rcu, rcu_cleanup_netpoll_info); } else RCU_INIT_POINTER(np->dev->npinfo, NULL); + + skb_pool_flush(np); } EXPORT_SYMBOL_GPL(__netpoll_cleanup);