Daniel Vetter 53d227f282 drm/i915: fixup seqno allocation logic for lazy_request ... Currently we reserve seqnos only when we emit the request to the ring (by bumping dev_priv->next_seqno), but start using it much earlier for ring->oustanding_lazy_request. When 2 threads compete for the gpu and run on two different rings (e.g. ddx on blitter vs. compositor) hilarity ensued, especially when we get constantly interrupted while reserving buffers. Breakage seems to have been introduced in commit 6f392d5486 Author: Chris Wilson <chris@chris-wilson.co.uk> Date: Sat Aug 7 11:01:22 2010 +0100 drm/i915: Use a common seqno for all rings. This patch fixes up the seqno reservation logic by moving it into i915_gem_next_request_seqno. The ring->add_request functions now superflously still return the new seqno through a pointer, that will be refactored in the next patch. Note that with this change we now unconditionally allocate a seqno, even when ->add_request might fail because the rings are full and the gpu died. But this does not open up a new can of worms because we can already leave behind an outstanding_request_seqno if e.g. the caller gets interrupted with a signal while stalling for the gpu in the eviciton paths. And with the bugfix we only ever have one seqno allocated per ring (and only that ring), so there are no ordering issues with multiple outstanding seqnos on the same ring. v2: Keep i915_gem_get_seqno (but move it to i915_gem.c) to make it clear that we only have one seqno counter for all rings. Suggested by Chris Wilson. v3: As suggested by Chris Wilson use i915_gem_next_request_seqno instead of ring->oustanding_lazy_request to make the follow-up refactoring more clearly correct. Also improve the commit message with issues discussed on irc. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45181 Tested-by: Nicolas Kalkhof nkalkhof()at()web.de Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>		2012-02-13 10:55:57 +01:00
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drm	drm/i915: fixup seqno allocation logic for lazy_request	2012-02-13 10:55:57 +01:00
stub	i915: select VIDEO_OUTPUT_CONTROL for ACPI_VIDEO	2011-04-13 09:10:25 +10:00
vga	drivers/gpu/vga/vgaarb.c: add missing kfree	2011-11-22 20:21:10 +00:00
Makefile	gpu: Add Intel GMA500(Poulsbo) Stub Driver	2010-10-26 11:00:13 +10:00