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 23DF81F8F0B for ; Thu, 14 Nov 2024 11:41:47 +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=1731584508; cv=none; b=qskUtSxySWaS+8lvGBcqNlzXGjkkSWVRwx6kFUOVnZre4PbHHHA12W9wR2VsAMpFotcm1eP6wPGuuqxF/m2vQIGru0UHmao9UGPMAl6UGtxry2ASU1B4Z8ee9jAp+dorDq1plng70FlAX32mZKTThvGR8X1q7UTNrOWUh1x/BVk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731584508; c=relaxed/simple; bh=gLgSyFYZ3SCU8+lxwN27I+1S8Wg6qKlEwHT6pGuDXAc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jdWo4eaXpKwI9OsXgNh61Ekn5G2MzdKaPjuMVaZJEY02eV6A3+h9wmD7d4gSkOBk5qFqzo5f9pwnMfKLUlTvW7obOvVjrSadlgQF5ExIBbje20E+pG+Hq6w0mfVC2rqej9EWj8fH6VMjceBioNHdRoBDo21yXWm+YHWPrywG8qw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=H/UuOO+1; 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="H/UuOO+1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1EB59C4CECD; Thu, 14 Nov 2024 11:41:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731584507; bh=gLgSyFYZ3SCU8+lxwN27I+1S8Wg6qKlEwHT6pGuDXAc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=H/UuOO+1dHRbtiUQMAwHdUHJyMyGDRV4dkOpY36fx+0/c41RlLNuOT9n7EyKRAHjv 1Svy29btIjERuHVKPAlsKFyixzc4brgcqssEBNtqP6e2OzXgCRWnkAp0Am3+Cv3bJS qv9tB2kEBsbbib/7SNXL8LHzXIXGAYwTZp40ZtbHtd5VM/e1uZrmny66c8qkLfx2OM SjHsx/njLH1oH/sZGaWoO54WdpiRcGsSWAP1OJ591H6BWslbfdEwaPhh4FFsbO/zBR yRUOluZaAE9qtHdyg4BKVMjAuKLvFQWJ4AVKogX25M8V+HuEe3M3RxB4HLoIx94gaP DpU6qv9pVnQaQ== Date: Thu, 14 Nov 2024 13:41:41 +0200 From: Leon Romanovsky To: Junxian Huang Cc: linux-rdma , Jason Gunthorpe , ynachum@amazon.com, Linuxarm , Chengchang Tang , wenglianfa Subject: Re: Why is the DENABLE_LTTNG compiler option in rdma-core disabled by default? Message-ID: <20241114114141.GE499069@unreal> References: <8fe49262-98cf-6b43-4f55-b09a8ae449ca@hisilicon.com> Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8fe49262-98cf-6b43-4f55-b09a8ae449ca@hisilicon.com> On Thu, Nov 14, 2024 at 02:57:21PM +0800, Junxian Huang wrote: > Hi all! > > We've been working on LTTng tracing for hns userspace provider > recently, and we wonder why the DENABLE_LTTNG compiler option > in rdma-core is disabled by default. > > If it's due to the concern about performance degradation, we have > tested it on hns and found no significant performance difference > when the tracepoints are disabled. > > Or is it because it introduces additional compilation dependency > on LTTng library? Yes, this is the reason. Most rdma-core users who use release version will never need trace library in their life. They don't need an extra dependency. Thanks > > Thanks, > Junxian