Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934258AbaFSSPV (ORCPT ); Thu, 19 Jun 2014 14:15:21 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:50416 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933173AbaFSSPS (ORCPT ); Thu, 19 Jun 2014 14:15:18 -0400 Date: Thu, 19 Jun 2014 11:19:18 -0700 From: Greg KH To: Rob Clark Cc: Maarten Lankhorst , linux-arch@vger.kernel.org, Thomas Hellstrom , Linux Kernel Mailing List , "dri-devel@lists.freedesktop.org" , "linaro-mm-sig@lists.linaro.org" , Thierry Reding , Colin Cross , Daniel Vetter , Sumit Semwal , "linux-media@vger.kernel.org" Subject: Re: [REPOST PATCH 1/8] fence: dma-buf cross-device synchronization (v17) Message-ID: <20140619181918.GA24155@kroah.com> References: <20140618102957.15728.43525.stgit@patser> <20140618103653.15728.4942.stgit@patser> <20140619011327.GC10921@kroah.com> <20140619170059.GA1224@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 19, 2014 at 01:45:30PM -0400, Rob Clark wrote: > On Thu, Jun 19, 2014 at 1:00 PM, Greg KH wrote: > > On Thu, Jun 19, 2014 at 10:00:18AM -0400, Rob Clark wrote: > >> On Wed, Jun 18, 2014 at 9:13 PM, Greg KH wrote: > >> > On Wed, Jun 18, 2014 at 12:36:54PM +0200, Maarten Lankhorst wrote: > >> >> +#define CREATE_TRACE_POINTS > >> >> +#include > >> >> + > >> >> +EXPORT_TRACEPOINT_SYMBOL(fence_annotate_wait_on); > >> >> +EXPORT_TRACEPOINT_SYMBOL(fence_emit); > >> > > >> > Are you really willing to live with these as tracepoints for forever? > >> > What is the use of them in debugging? Was it just for debugging the > >> > fence code, or for something else? > >> > > >> >> +/** > >> >> + * fence_context_alloc - allocate an array of fence contexts > >> >> + * @num: [in] amount of contexts to allocate > >> >> + * > >> >> + * This function will return the first index of the number of fences allocated. > >> >> + * The fence context is used for setting fence->context to a unique number. > >> >> + */ > >> >> +unsigned fence_context_alloc(unsigned num) > >> >> +{ > >> >> + BUG_ON(!num); > >> >> + return atomic_add_return(num, &fence_context_counter) - num; > >> >> +} > >> >> +EXPORT_SYMBOL(fence_context_alloc); > >> > > >> > EXPORT_SYMBOL_GPL()? Same goes for all of the exports in here. > >> > Traditionally all of the driver core exports have been with this > >> > marking, any objection to making that change here as well? > >> > >> tbh, I prefer EXPORT_SYMBOL().. well, I'd prefer even more if there > >> wasn't even a need for EXPORT_SYMBOL_GPL(), but sadly it is a fact of > >> life. We already went through this debate once with dma-buf. We > >> aren't going to change $evil_vendor's mind about non-gpl modules. The > >> only result will be a more flugly convoluted solution (ie. use syncpt > >> EXPORT_SYMBOL() on top of fence EXPORT_SYMBOL_GPL()) just as a > >> workaround, with the result that no-one benefits. > > > > It has been proven that using _GPL() exports have caused companies to > > release their code "properly" over the years, so as these really are > > Linux-only apis, please change them to be marked this way, it helps > > everyone out in the end. > > Well, maybe that is the true in some cases. But it certainly didn't > work out that way for dma-buf. And I think the end result is worse. > > I don't really like coming down on the side of EXPORT_SYMBOL() instead > of EXPORT_SYMBOL_GPL(), but if we do use EXPORT_SYMBOL_GPL() then the > result will only be creative workarounds using the _GPL symbols > indirectly by whatever is available via EXPORT_SYMBOL(). I don't > really see how that will be better. You are saying that you _know_ companies will violate our license, so you should just "give up"? And how do you know people aren't working on preventing those "indirect" usages as well? :) Sorry, I'm not going to give up here, again, it has proven to work in the past in changing the ways of _very_ large companies, why stop now? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/