From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 27 Jul 2021 22:12:51 -0700 Message-ID: <87eebjnhrg.wl-ashutosh.dixit@intel.com> From: "Dixit, Ashutosh" In-Reply-To: <87fsvznqmj.wl-ashutosh.dixit@intel.com> References: <20210726120310.1115522-1-matthew.auld@intel.com> <87fsvznqmj.wl-ashutosh.dixit@intel.com> MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Subject: Re: [igt-dev] [PATCH i-g-t 1/7] lib/i915/gem_mman: add FIXED mmap mode List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: igt-dev-bounces@lists.freedesktop.org Sender: "igt-dev" To: igt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, Petri Latvala List-ID: On Tue, 27 Jul 2021 19:01:24 -0700, Dixit, Ashutosh wrote: > > On Mon, 26 Jul 2021 05:03:04 -0700, Matthew Auld wrote: > > > > diff --git a/lib/i915/gem_mman.c b/lib/i915/gem_mman.c > > index 4b4f2114..e2514f0c 100644 > > --- a/lib/i915/gem_mman.c > > +++ b/lib/i915/gem_mman.c > > @@ -497,6 +497,43 @@ void *gem_mmap_offset__cpu(int fd, uint32_t handle, uint64_t offset, > > return ptr; > > } > > > > +#define LOCAL_I915_MMAP_OFFSET_FIXED 4 > > Cc: @Petri Latvala > > This use of LOCAL declarations is more related to the methodology we follow > in IGT rather than this patch. We have seen in the past that such LOCAL's > linger on in the code for months and years till someone decides to clean > them so the question is can we prevent these LOCAL's from getting > introduced in the first place. > > One reason for these is that we sync IGT headers with drm-next whereas IGT > is used to test drm-tip. So the delta between the two results in such > LOCAL's as in this case. > > My proposal is that even if we don't start sync'ing IGT headers with > drm-tip (instead of drm-next) we allow direct modification of the headers > when needed to avoid introducing such LOCAL's. So in the above case we > would add: > > #define I915_MMAP_OFFSET_FIXED 4 > > to i915_drm.h as part of this patch and then just use > I915_MMAP_OFFSET_FIXED. If another sync happens from drm-next before this > #define has appeared there, the compile will break and whoever syncs will > need to add this again to i915_drm.h. > > What do people think about a scheme such as this? The other, perhaps > better, option of course is to sync the headers directly with drm-tip > (whenever and as often as needed). But the goal in both cases is to avoid > LOCAL's, or other things like #ifndef's distributed throughout multiple > source files which we also do in such cases. A centralized internal header > to contain such declarations might not be so bad. Thanks. I have submitted a patch based on this last statement here: https://patchwork.freedesktop.org/series/93096/ _______________________________________________ igt-dev mailing list igt-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/igt-dev