From patchwork Fri Mar 1 23:05:40 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jakub Kicinski X-Patchwork-Id: 13579236 X-Patchwork-Delegate: kuba@kernel.org Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CCCA35EE87 for ; Fri, 1 Mar 2024 23:05:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709334352; cv=none; b=fWpLPdWRxJgHlRDiRf5QW50kAhnZe6NmZE68ZEZo44pd0BWGO2rhWpamaMoXNE3EH+9kbVhzQhdtXXdYDH7k1YYB9JkLY5lTrt91v2rLbXFY/cRCHzirAl4qUfjFWbC87f72QvqsRZ5xUMK6vFsmkSm9OBCYJDFFOy42z2DVj+c= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709334352; c=relaxed/simple; bh=R79Jbbmzra6Cjtq8MYHP5ttSVah2jSDgzWPs1rikcWM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mVA+wrb9f0lsVw1rR7GIcuQ/X7JdPiNrbcVpoObptPwXgRKDtxi6up+kAzjo9f3ENWy62YokvEc8TLSFK9E46UcSlS05cvMLkpl0+OrQ2G2suUsNIhvoeiusq1YaQyBGxgD0Rlm0oxRZsduhGO2UzTOO/a3YQ78tJnf0ei25eQw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rnEDAvW1; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rnEDAvW1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 28952C43394; Fri, 1 Mar 2024 23:05:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709334352; bh=R79Jbbmzra6Cjtq8MYHP5ttSVah2jSDgzWPs1rikcWM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rnEDAvW1cgiXJvJvduBqkCSTdZoXmyObuTyS1wvmD4jnAdJ/5j00MLZuryfc6wxbu Lxrm+0eiaMDkPHM1NUm4DxkSj3OaMQ7HbWm69DS1sXgL6vJD1d+52kjPPaCbzSiFUm vFXA4wFLICrgd9eORLOirK2NvA9LwsU5vHiGrS7bwPpJCfQyNwSPtvHI5xbMFlCJ3X 6pu/Z+cJRpOw60qDUzPDHYhTGU9iCfC7IWhAaZPcnnZJtWSBzaCyan2bMtljhO0rOr y3KHeV8I/0G0guUZUEd8/ujuEgBGqKeKcT1qpCbtCnpfqpYCrkEbTzzoaPqIrkEunf WjTfG1w4Vk1Xg== From: Jakub Kicinski To: davem@davemloft.net Cc: netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, jiri@resnulli.us, donald.hunter@gmail.com, Jakub Kicinski Subject: [PATCH net-next 2/4] tools: ynl: allow setting recv() size Date: Fri, 1 Mar 2024 15:05:40 -0800 Message-ID: <20240301230542.116823-3-kuba@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240301230542.116823-1-kuba@kernel.org> References: <20240301230542.116823-1-kuba@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org Make the size of the buffer we use for recv() configurable. The details of the buffer sizing in netlink are somewhat arcane, we could spend a lot of time polishing this API. Let's just leave some hopefully helpful comments for now. This is a for-developers-only feature, anyway. Signed-off-by: Jakub Kicinski --- tools/net/ynl/lib/ynl.py | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py index 92ade9105f31..bc5a526dbb99 100644 --- a/tools/net/ynl/lib/ynl.py +++ b/tools/net/ynl/lib/ynl.py @@ -84,6 +84,10 @@ from .nlspec import SpecFamily return f"Netlink error: {os.strerror(-self.nl_msg.error)}\n{self.nl_msg}" +class ConfigError(Exception): + pass + + class NlAttr: ScalarFormat = namedtuple('ScalarFormat', ['native', 'big', 'little']) type_formats = { @@ -400,7 +404,8 @@ genl_family_name_to_id = None class YnlFamily(SpecFamily): - def __init__(self, def_path, schema=None, process_unknown=False): + def __init__(self, def_path, schema=None, process_unknown=False, + recv_size=131072): super().__init__(def_path, schema) self.include_raw = False @@ -423,6 +428,16 @@ genl_family_name_to_id = None self.async_msg_ids = set() self.async_msg_queue = [] + # Note that netlink will use conservative (min) message size for + # the first dump recv() on the socket, our setting will only matter + # from the second recv() on. + self._recv_size = recv_size + # Netlink will always allocate at least PAGE_SIZE - sizeof(skb_shinfo) + # for a message, so smaller receive sizes will lead to truncation. + # Note that the min size for other families may be larger than 4k! + if self._recv_size < 4000: + raise ConfigError() + for msg in self.msgs.values(): if msg.is_async: self.async_msg_ids.add(msg.rsp_value) @@ -799,7 +814,7 @@ genl_family_name_to_id = None def check_ntf(self): while True: try: - reply = self.sock.recv(128 * 1024, socket.MSG_DONTWAIT) + reply = self.sock.recv(self._recv_size, socket.MSG_DONTWAIT) except BlockingIOError: return @@ -854,7 +869,7 @@ genl_family_name_to_id = None done = False rsp = [] while not done: - reply = self.sock.recv(128 * 1024) + reply = self.sock.recv(self._recv_size) nms = NlMsgs(reply, attr_space=op.attr_set) for nl_msg in nms: if nl_msg.extack: