From mboxrd@z Thu Jan 1 00:00:00 1970 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 5ED10225388; Wed, 26 Feb 2025 17:12:09 +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=1740589930; cv=none; b=Br0PApZQO+nAJV0rnY0J0bQAHb/EnVDPkpQK6UVnQyvpsJZdXEiu8mBMS8bBAuzo2pEfk8QazzSS1Z3Wb2faW5Cq6VYiX1/468XME0ZSXB7lTF0m8Bl2YGG9Y5Jv7MDoyKc7TOosnrUDeMqumLy9co6M4qpZPOfnTcmQMojT2XI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740589930; c=relaxed/simple; bh=bCFsSQk2TidtJIcQabLL//jFR8PWOOUExaamwCnHd/U=; h=Content-Type:Message-ID:Date:MIME-Version:Subject:To:Cc: References:From:In-Reply-To; b=a1OZDFJs+LKZxX4CmUSZjdIEPvchpA/f3zaewbZn2DhRD3m3MagrmH/QEiF2aRT1x0cLXLxV48eOsHJOUFHIUAFC3fbgfvp+mILoaCK55xGWqM1Avbl5YtUw2V/O11if7rcbS+LySYdm8JRRFu13ZAegm9aIczhPsL7OdV9oN54= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dHfN+azv; 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="dHfN+azv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2FCEDC4CEFF; Wed, 26 Feb 2025 17:12:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740589929; bh=bCFsSQk2TidtJIcQabLL//jFR8PWOOUExaamwCnHd/U=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=dHfN+azv4iTM7t4HCjo5TdiYx2W9Qt4QVAkr4RIg+WgSKht2veBXhZ2WxaYxCw8Mn d7PjK//WZFoA08BFizGZWqmP8bpY4mUVmk3oWGAo0WZImxIQPbu/UMEK71ze9QkRPG UsBfrulQdP8Sw5jszB9gnwxpDRzPt4AKeA32vJUP2QOfiCedRZc4l4bZC5ZzaouUkH Gya3V3gJr5OjCP1cS+oB7aRIf6ojECHCbIUUvPOeDt4PqU3UadBwBpEJHhEDA4SXZR KSc7H7pifNpBxvWQT1aq8OHuKlat8147i8JnYSnt+pdWFeUEgYPTNm8/SbSWDJoPuj 0+1ANN9R/aTPQ== Content-Type: multipart/mixed; boundary="------------VC1cxLU5U4YFqksw5cz0xkIc" Message-ID: <7e148fd2-b4b7-49a1-958f-4b0838571245@kernel.org> Date: Wed, 26 Feb 2025 10:12:08 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next] trace: tcp: Add tracepoint for tcp_sendmsg() Content-Language: en-US To: Breno Leitao Cc: Eric Dumazet , Neal Cardwell , Kuniyuki Iwashima , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, kernel-team@meta.com, yonghong.song@linux.dev References: <20250224-tcpsendmsg-v1-1-bac043c59cc8@debian.org> <559f3da9-4b3d-41c2-bf44-18329f76e937@kernel.org> <20250226-cunning-innocent-degu-d6c2fe@leitao> From: David Ahern In-Reply-To: <20250226-cunning-innocent-degu-d6c2fe@leitao> This is a multi-part message in MIME format. --------------VC1cxLU5U4YFqksw5cz0xkIc Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2/26/25 9:10 AM, Breno Leitao wrote: >> Also, if a tracepoint is added, inside of tcp_sendmsg_locked would cover >> more use cases (see kernel references to it). > > Agree, this seems to provide more useful information > >> We have a patch for a couple years now with a tracepoint inside the > > Sorry, where do you have this patch? is it downstream? company tree. Attached. Where to put tracepoints and what arguments to supply so that it is beneficial to multiple users is always a touchy subject :-), so I have not tried to push the patch out. sock arg should be added to it for example. The key is to see how tcp_sendmsg_locked breaks up the buffers, and then another one in tcp_write_xmit to see when the actual push out happens. 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