From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <45C618FA.3060000@us.ibm.com> Date: Sun, 04 Feb 2007 11:33:46 -0600 From: Maynard Johnson MIME-Version: 1.0 To: Arnd Bergmann Subject: Re: [Cbe-oss-dev] [RFC, PATCH 4/4] Add support to OProfile for profiling Cell BE SPUs -- update References: <45BE4ED0.5030808@us.ibm.com> <200701300839.05144.arnd@arndb.de> <45C51F6C.7080300@us.ibm.com> <200702040352.03792.arnd@arndb.de> In-Reply-To: <200702040352.03792.arnd@arndb.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linuxppc-dev@ozlabs.org, cbe-oss-dev@ozlabs.org, oprofile-list@lists.sourceforge.net, linux-kernel@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Arnd Bergmann wrote: >On Sunday 04 February 2007 00:49, Maynard Johnson wrote: > > >>I seem to recall looking at this option a while back, but didn't go that >>route since struct spu_context is opaque to me. With such a teqnique, I >>could then use a simple 16-element array of pointers to cached_info >>objects, creating them as needed when spu_context->profile_private is >>NULL. I suppose the better option for now is to add a >>get_profile_private() function to SPUFs, rather than requiring >>spu_context to be visible. >> >> > >Yes, that sounds good. Note that the file providing the >spufs_get_profile_private (and respective spufs_set_profile_private) >functions needs to be compiled into the kernel then in case oprofile >gets linked in but spufs is a module. > > Hmm . . . we already depend on the register/unregister functions in sched.c, so my patch changes the oprofile Kconfig to default to 'm' and 'depends on SPU_FS'. >I think it would also be necessary to have another interface for cleaning >up this data when spufs destroys the context. That could possibly >a variation of the existing notifier call, or a new call, or you >establish the convention that if the private pointer is non-NULL, >spufs will kfree it. > > Yes, I was thnking along the lines of your last suggestion. I presume OProfile gets notified (object_id == 0) before the context is actually destroyed. At that time, we would NULL-out the reference to the cached_info, so then SPUFS would kfree it at destroy time. -Maynard > Arnd <>< > >