From patchwork Thu Apr 18 07:32:37 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 13634256 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) (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 8EF1D53E3F for ; Thu, 18 Apr 2024 07:32:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713425578; cv=none; b=PUw/ncJbfkkgT4P9CyoXAXAViWPpXtbCleK3AAvvntwOJvxIWEef6hjOdeYwMeOGKgu2I9jkYiD5XE2nfmQ6jIYKYRF10CMjCtpqAg8HpOrc/xXRL8TUY7fe76NK86gUMFaTR6vWFGc97sHOodv2vZZlHG+58n3Xsrmq6ZpWfEE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713425578; c=relaxed/simple; bh=o1C4rkkaRhTIn8JKPJwSZY4szztCcHHb3B+Gqgn7Lf8=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=YQe+MWMqbLCCZZ/TpUKcnem3jrhGDqIpnYqJXz5r/pBvO0jjJR4kqDBcNm29M+2orMlI7u5+p+peGnvG88+HpeZI8CiEcNQA0GgYAoPJIVeLyWtKo62PjkyzVjEYJNLgU+NTFZlThrnhqbgvQXNQZXGnorD5XeGROItpPoRlRDY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=F5ahAiP7; arc=none smtp.client-ip=209.85.219.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="F5ahAiP7" Received: by mail-yb1-f202.google.com with SMTP id 3f1490d57ef6-de4691a0918so603051276.0 for ; Thu, 18 Apr 2024 00:32:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1713425575; x=1714030375; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=C2eTMFAEJNkYixMviBRtFiCkX59OC1AUV6clrpwB4sk=; b=F5ahAiP782aNdklTiepRv3LeTZrM8IshnhMtgXDBWeTkIORQyWNZrC3lOIfsDSKt4d FedVxykQqS7jrPHPLPG1lGtT9YDHm77AZgeA+CEZyXSdYcKBGov6mZGygsO09c8vziEf GK1xtMcQS43Tu3hra+HLmLGddtLBFU7tZ6uC/7vw6R7/A4C0k4WD9D28i8SYqWj4I2OC YKxzvqs0cts+4PdfUULUJsn7h8H+pAt93lL6HrnZSNfOBdCd0EJIy18+zC13S7l2V+l5 H4yMQM5IJcbw6/QRk+713sRVLCBFWe24MXJonTJEirk2AJVnJWwK7FjEj7+WK+uHQT7x EWDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713425575; x=1714030375; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=C2eTMFAEJNkYixMviBRtFiCkX59OC1AUV6clrpwB4sk=; b=cnfxfNpNCcO6m4dwC+JQwqBzFw8tjYLAJYDHnwOZzUo1ojsFgRduS/9nARUlvv8/Y+ F/HkXD6bvnqgL2m7YxBe8pkBUDaYHL3AtwflIdJXIRhb+w0UzuUJ4i8VXhq8nCG5A5rl M+81bAs5ClNfpgSDi6mv6QrXT5vkyYETiGBthRLiiOFZZKtW2907RfwJw/AF7M2KTB/u +2SgAuso+4mRUqf1aetwrhsmxfsfC+rdkdOblEfqOJPyipDf8Vm4kW9EyHF/vywPqLBy Qay+STWhKmrQ6h9PRwEngbf8YM0lggEoEOu3AAYYX6xY1vK7O5zWffGZLoMiTLhFfzo6 Cq6A== X-Forwarded-Encrypted: i=1; AJvYcCX27TJTD4O7HTYxFNKkH5q88eVH4g5j1VAhX17nh9F0sLHHEZPBnA3rKAH2yvPR9PxZ2EUG8diRTsTHY4+N44MivZEsU6Nv X-Gm-Message-State: AOJu0YzspD5MK1XL4J1ZsO8dyqluzD8gdngDg59YfThGTI+GSCLwzRVX zVS/Nu3e8YywhTipn2TF8qaGc6p/uZ1f7wCyh3FWx2zIp7hOCzfHuytEKBnM7t0exie2Ud6zi4j 7QWHpLgaqMg== X-Google-Smtp-Source: AGHT+IFH59AxRrWBkRPNTeChaBvTZL4dve5kvy/nSuVhcqBVrBxiO/FVIp+nqFF1JVAjYp9JVEdTmkwwcv/41g== X-Received: from edumazet1.c.googlers.com ([fda3:e722:ac3:cc00:2b:7d90:c0a8:395a]) (user=edumazet job=sendgmr) by 2002:a05:6902:1001:b0:dda:c4ec:7db5 with SMTP id w1-20020a056902100100b00ddac4ec7db5mr449112ybt.4.1713425575648; Thu, 18 Apr 2024 00:32:55 -0700 (PDT) Date: Thu, 18 Apr 2024 07:32:37 +0000 In-Reply-To: <20240418073248.2952954-1-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240418073248.2952954-1-edumazet@google.com> X-Mailer: git-send-email 2.44.0.683.g7961c838ac-goog Message-ID: <20240418073248.2952954-4-edumazet@google.com> Subject: [PATCH v2 net-next 03/14] net_sched: sch_cbs: implement lockless cbs_dump() From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: Jamal Hadi Salim , Simon Horman , " =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= " , Cong Wang , Jiri Pirko , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet X-Patchwork-Delegate: kuba@kernel.org Instead of relying on RTNL, cbs_dump() can use READ_ONCE() annotations, paired with WRITE_ONCE() ones in cbs_change(). Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman --- net/sched/sch_cbs.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/net/sched/sch_cbs.c b/net/sched/sch_cbs.c index 69001eff0315584df23a24f81ae3b4cf7bf5fd79..939425da18955bc8a3f3d2d5b852b2585e9bcaee 100644 --- a/net/sched/sch_cbs.c +++ b/net/sched/sch_cbs.c @@ -389,11 +389,11 @@ static int cbs_change(struct Qdisc *sch, struct nlattr *opt, } /* Everything went OK, save the parameters used. */ - q->hicredit = qopt->hicredit; - q->locredit = qopt->locredit; - q->idleslope = qopt->idleslope * BYTES_PER_KBIT; - q->sendslope = qopt->sendslope * BYTES_PER_KBIT; - q->offload = qopt->offload; + WRITE_ONCE(q->hicredit, qopt->hicredit); + WRITE_ONCE(q->locredit, qopt->locredit); + WRITE_ONCE(q->idleslope, qopt->idleslope * BYTES_PER_KBIT); + WRITE_ONCE(q->sendslope, qopt->sendslope * BYTES_PER_KBIT); + WRITE_ONCE(q->offload, qopt->offload); return 0; } @@ -459,11 +459,11 @@ static int cbs_dump(struct Qdisc *sch, struct sk_buff *skb) if (!nest) goto nla_put_failure; - opt.hicredit = q->hicredit; - opt.locredit = q->locredit; - opt.sendslope = div64_s64(q->sendslope, BYTES_PER_KBIT); - opt.idleslope = div64_s64(q->idleslope, BYTES_PER_KBIT); - opt.offload = q->offload; + opt.hicredit = READ_ONCE(q->hicredit); + opt.locredit = READ_ONCE(q->locredit); + opt.sendslope = div64_s64(READ_ONCE(q->sendslope), BYTES_PER_KBIT); + opt.idleslope = div64_s64(READ_ONCE(q->idleslope), BYTES_PER_KBIT); + opt.offload = READ_ONCE(q->offload); if (nla_put(skb, TCA_CBS_PARMS, sizeof(opt), &opt)) goto nla_put_failure;