Re: [Intel-gfx] [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper
On Tue, 9 Oct 2012 19:59:02 +0200, Daniel Vetter wrote: > The obj->pages to obj->pages->sgl rework introduced this helper, but > it doesn't actually work for n % SG_MAX_SINGLE_ALLOC == 0. > > This is exercised by the improved hangman tests and the gem_exec_big > test in i-g-t. > > Signed-off-by: Daniel Vetter I had to think about that harder than I should, to be sure we handled the case where the last element was a page and not a chainptr correctly. On hindsight, the code is clearly bogus for the n==SG_MAX_SINGLE_ALLOC because n is an index. My original thought was to use 'nth' instead and I believe that it would have helped prevent my confusion. Ah hindisght. Reviewed-by: Chris Wilson -Chris -- Chris Wilson, Intel Open Source Technology Centre ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper
On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter wrote: > The obj->pages to obj->pages->sgl rework introduced this helper, but > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > For simplicity (and since right now I seem to be too stupid to see > the bug), let's just grab the right page with a for_each_sg loop. > > This is exercised by the improved hangman tests and the gem_exec_big > test in i-g-t. > > v2: Compared to v1, don't try to be clever since I seemingly only > manage to prove that I'm not clever. Only I expect that loop to show up on profiles even higher than the sg_next() from pwrite. :| I expect it to have a measureable impact upon relocation throughput, so I should measure it... -Chris -- Chris Wilson, Intel Open Source Technology Centre ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper
On Tue, 09 Oct 2012 23:16:02 +0100, Chris Wilson wrote: > On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter > wrote: > > The obj->pages to obj->pages->sgl rework introduced this helper, but > > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > > > For simplicity (and since right now I seem to be too stupid to see > > the bug), let's just grab the right page with a for_each_sg loop. > > > > This is exercised by the improved hangman tests and the gem_exec_big > > test in i-g-t. > > > > v2: Compared to v1, don't try to be clever since I seemingly only > > manage to prove that I'm not clever. > > Only I expect that loop to show up on profiles even higher than the > sg_next() from pwrite. :| > > I expect it to have a measureable impact upon relocation throughput, > so I should measure it... > -Chris > > -- > Chris Wilson, Intel Open Source Technology Centre > ___ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx From: Chris Wilson Subject: Re: [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper To: Daniel Vetter , Intel Graphics Development Cc: Daniel Vetter In-Reply-To: <1349815848-1824-1-git-send-email-daniel.vet...@ffwll.ch> References: <84c8a8$624...@orsmga001.jf.intel.com> <1349815848-1824-1-git-send-email-daniel.vet...@ffwll.ch> On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter wrote: > The obj->pages to obj->pages->sgl rework introduced this helper, but > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > For simplicity (and since right now I seem to be too stupid to see > the bug), let's just grab the right page with a for_each_sg loop. > > This is exercised by the improved hangman tests and the gem_exec_big > test in i-g-t. > > v2: Compared to v1, don't try to be clever since I seemingly only > manage to prove that I'm not clever. > > Signed-off-by: Daniel Vetter Looks like my worries are baseless. It can always be attacked latter if need be. I'd still like to know what the mistake was... Reviewed-by: Chris Wilson -Chris -- Chris Wilson, Intel Open Source Technology Centre ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper
On Wed, Oct 10, 2012 at 10:01:47AM +0100, Chris Wilson wrote: > On Tue, 09 Oct 2012 23:16:02 +0100, Chris Wilson > wrote: > > On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter > > wrote: > > > The obj->pages to obj->pages->sgl rework introduced this helper, but > > > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > > > > > For simplicity (and since right now I seem to be too stupid to see > > > the bug), let's just grab the right page with a for_each_sg loop. > > > > > > This is exercised by the improved hangman tests and the gem_exec_big > > > test in i-g-t. > > > > > > v2: Compared to v1, don't try to be clever since I seemingly only > > > manage to prove that I'm not clever. > > > > Only I expect that loop to show up on profiles even higher than the > > sg_next() from pwrite. :| > > > > I expect it to have a measureable impact upon relocation throughput, > > so I should measure it... > > -Chris > > > > -- > > Chris Wilson, Intel Open Source Technology Centre > > ___ > > Intel-gfx mailing list > > Intel-gfx@lists.freedesktop.org > > http://lists.freedesktop.org/mailman/listinfo/intel-gfx > From: Chris Wilson > Subject: Re: [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper > To: Daniel Vetter , Intel Graphics Development > > Cc: Daniel Vetter > In-Reply-To: <1349815848-1824-1-git-send-email-daniel.vet...@ffwll.ch> > References: <84c8a8$624...@orsmga001.jf.intel.com> > <1349815848-1824-1-git-send-email-daniel.vet...@ffwll.ch> > > On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter > wrote: > > The obj->pages to obj->pages->sgl rework introduced this helper, but > > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > > > For simplicity (and since right now I seem to be too stupid to see > > the bug), let's just grab the right page with a for_each_sg loop. > > > > This is exercised by the improved hangman tests and the gem_exec_big > > test in i-g-t. > > > > v2: Compared to v1, don't try to be clever since I seemingly only > > manage to prove that I'm not clever. > > > > Signed-off-by: Daniel Vetter > > Looks like my worries are baseless. It can always be attacked latter if > need be. I'd still like to know what the mistake was... I think it was two mistakes: - One was the off-by-one fixed in v1. - Second seemed to be the special case that if the table fits exactly, sg_alloc doesn't set a chain ptr with another sg table with just one entry. But like the commit message says, I've failed to be clever enough yesterday to make it work. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper
On Wed, Oct 10, 2012 at 10:01:47AM +0100, Chris Wilson wrote: > On Tue, 09 Oct 2012 23:16:02 +0100, Chris Wilson > wrote: > > On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter > > wrote: > > > The obj->pages to obj->pages->sgl rework introduced this helper, but > > > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > > > > > For simplicity (and since right now I seem to be too stupid to see > > > the bug), let's just grab the right page with a for_each_sg loop. > > > > > > This is exercised by the improved hangman tests and the gem_exec_big > > > test in i-g-t. > > > > > > v2: Compared to v1, don't try to be clever since I seemingly only > > > manage to prove that I'm not clever. > > > > Only I expect that loop to show up on profiles even higher than the > > sg_next() from pwrite. :| > > > > I expect it to have a measureable impact upon relocation throughput, > > so I should measure it... > > -Chris > > > > -- > > Chris Wilson, Intel Open Source Technology Centre > > ___ > > Intel-gfx mailing list > > Intel-gfx@lists.freedesktop.org > > http://lists.freedesktop.org/mailman/listinfo/intel-gfx > From: Chris Wilson > Subject: Re: [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper > To: Daniel Vetter , Intel Graphics Development > > Cc: Daniel Vetter > In-Reply-To: <1349815848-1824-1-git-send-email-daniel.vet...@ffwll.ch> > References: <84c8a8$624...@orsmga001.jf.intel.com> > <1349815848-1824-1-git-send-email-daniel.vet...@ffwll.ch> > > On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter > wrote: > > The obj->pages to obj->pages->sgl rework introduced this helper, but > > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > > > For simplicity (and since right now I seem to be too stupid to see > > the bug), let's just grab the right page with a for_each_sg loop. > > > > This is exercised by the improved hangman tests and the gem_exec_big > > test in i-g-t. > > > > v2: Compared to v1, don't try to be clever since I seemingly only > > manage to prove that I'm not clever. > > > > Signed-off-by: Daniel Vetter > > Looks like my worries are baseless. It can always be attacked latter if > need be. I'd still like to know what the mistake was... > > Reviewed-by: Chris Wilson Merged to -fixes, with the missing regression-sha1 citation added. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper
On Wed, 10 Oct 2012 11:21:44 +0200, Daniel Vetter wrote: > On Wed, Oct 10, 2012 at 10:01:47AM +0100, Chris Wilson wrote: > > On Tue, 09 Oct 2012 23:16:02 +0100, Chris Wilson > > wrote: > > > On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter > > > wrote: > > > > The obj->pages to obj->pages->sgl rework introduced this helper, but > > > > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > > > > > > > For simplicity (and since right now I seem to be too stupid to see > > > > the bug), let's just grab the right page with a for_each_sg loop. > > > > > > > > This is exercised by the improved hangman tests and the gem_exec_big > > > > test in i-g-t. > > > > > > > > v2: Compared to v1, don't try to be clever since I seemingly only > > > > manage to prove that I'm not clever. > > > > > > Only I expect that loop to show up on profiles even higher than the > > > sg_next() from pwrite. :| > > > > > > I expect it to have a measureable impact upon relocation throughput, > > > so I should measure it... > > > -Chris > > > > > > -- > > > Chris Wilson, Intel Open Source Technology Centre > > > ___ > > > Intel-gfx mailing list > > > Intel-gfx@lists.freedesktop.org > > > http://lists.freedesktop.org/mailman/listinfo/intel-gfx > > From: Chris Wilson > > Subject: Re: [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper > > To: Daniel Vetter , Intel Graphics Development > > > > Cc: Daniel Vetter > > In-Reply-To: <1349815848-1824-1-git-send-email-daniel.vet...@ffwll.ch> > > References: <84c8a8$624...@orsmga001.jf.intel.com> > > <1349815848-1824-1-git-send-email-daniel.vet...@ffwll.ch> > > > > On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter > > wrote: > > > The obj->pages to obj->pages->sgl rework introduced this helper, but > > > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > > > > > For simplicity (and since right now I seem to be too stupid to see > > > the bug), let's just grab the right page with a for_each_sg loop. > > > > > > This is exercised by the improved hangman tests and the gem_exec_big > > > test in i-g-t. > > > > > > v2: Compared to v1, don't try to be clever since I seemingly only > > > manage to prove that I'm not clever. > > > > > > Signed-off-by: Daniel Vetter > > > > Looks like my worries are baseless. It can always be attacked latter if > > need be. I'd still like to know what the mistake was... > > > > Reviewed-by: Chris Wilson > > Merged to -fixes, with the missing regression-sha1 citation added. > -Daniel > -- > Daniel Vetter > Software Engineer, Intel Corporation > +41 (0) 79 365 57 48 - http://blog.ffwll.ch From: Chris Wilson Subject: Re: [Intel-gfx] [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper To: Daniel Vetter Cc: Daniel Vetter , Intel Graphics Development In-Reply-To: <20121010091538.GB5533@phenom.ffwll.local> References: <84c8a8$624...@orsmga001.jf.intel.com> <1349815848-1824-1-git-send-email-daniel.vet...@ffwll.ch> <6c3329$6m5...@orsmga002.jf.intel.com> <453bf0$61a...@azsmga001.ch.intel.com> <20121010091538.GB5533@phenom.ffwll.local> On Wed, 10 Oct 2012 11:15:38 +0200, Daniel Vetter wrote: > On Wed, Oct 10, 2012 at 10:01:47AM +0100, Chris Wilson wrote: > > On Tue, 09 Oct 2012 23:16:02 +0100, Chris Wilson > > wrote: > > > On Tue, 9 Oct 2012 22:50:48 +0200, Daniel Vetter > > > wrote: > > > > The obj->pages to obj->pages->sgl rework introduced this helper, but > > > > it doesn't actually work for n >= SG_MAX_SINGLE_ALLOC. > > > > > > > > For simplicity (and since right now I seem to be too stupid to see > > > > the bug), let's just grab the right page with a for_each_sg loop. > > > > > > > > This is exercised by the improved hangman tests and the gem_exec_big > > > > test in i-g-t. > > > > > > > > v2: Compared to v1, don't try to be clever since I seemingly only > > > > manage to prove that I'm not clever. > > > > > > Only I expect that loop to show up on profiles even higher than the > > > sg_next() from pwrite. :| > > > > > > I expect it to have a measureable impact
Re: [Intel-gfx] [PATCH] drm/i915: fixup i915_gem_object_get_page inline helper
On Wed, Oct 10, 2012 at 12:11:52PM +0100, Chris Wilson wrote: > Note that just because we have n == MAX elements left, does not imply > that there are only MAX elements left in the scatterlist and so we may > not be on the last chain, and the nth element may in fact be a chain ptr. > > This is exercised by the improved hangman tests and the gem_exec_big > test in i-g-t. > > This regression has been introduced in > > commit 9da3da660d8c19a54f6e93361d147509be3fff84 > Author: Chris Wilson > Date: Fri Jun 1 15:20:22 2012 +0100 > >drm/i915: Replace the array of pages with a scatterlist > > v2: KISS, replace the direct lookup with a for_each_sg() [danvet] > v3: Try to be clever again. > > Signed-off-by: Chris Wilson I've merged this one and dropped v2 from -fixes, thanks. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
