From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750721AbWHYHFI (ORCPT ); Fri, 25 Aug 2006 03:05:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750929AbWHYHFI (ORCPT ); Fri, 25 Aug 2006 03:05:08 -0400 Received: from liaag1af.mx.compuserve.com ([149.174.40.32]:45518 "EHLO liaag1af.mx.compuserve.com") by vger.kernel.org with ESMTP id S1750721AbWHYHFG (ORCPT ); Fri, 25 Aug 2006 03:05:06 -0400 Date: Fri, 25 Aug 2006 02:56:37 -0400 From: Chuck Ebbert <76306.1226@compuserve.com> Subject: Re: [PATCH 9/18] 2.6.17.9 perfmon2 patch for review: kernel-level interface To: Andrew Morton Cc: Christoph Hellwig , linux-kernel , Stephane Eranian Message-ID: <200608250300_MC3-1-C942-6359@compuserve.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 23 Aug 2006 15:54:47 -0700, Andrew Morton wrote: > > > Some users have requested the ability to create a monitoring session > > > with perfmon2 from iside the kernel using a kernel thread. Perfmon2 > > > leverages a lot of kernel mechanisms which are not easy to use for > > > inside the kernel: e.g. file descriptor, signals, system calls. > > > > Again, please drop this. There are no planned intree kernel users > > so far, and once we add them we can architect a proper API for them. > > Getting rid of this should also help to collapse the tons of useless > > abstractions layers in the current perfmon code. > > > > Yes, I think we either need a stronger argument for including this code, or > we drop it. This interface is for people writing kprobes who want to do performance monitoring within their probe code. There will probably never be any in-kernel users, just like there are no in-kernel users of kprobes. > It is especially worrisome that the exports which are added here are plain > old EXPORT_SYMBOL(). kprobes exports are all GPL, so these should be too. -- Chuck