First, I don't think this whole series is ready for merge yet. It is
however ready for a review, and I think a lot of the prep patches in the
series could be merged to make my rebasing life a bit easier. I cannot
continue ignoring pretty much all emails/bugs as I have for the last
month to wrap up this series. The current state is on my IVB, things are
pretty stable. I've seen one unexplained hang, but I'm hopeful review
might help me uncover/explain.
This patch series introduces the next step in enabling full PPGTT, which
is per fd address space/context, and it also contains the previously
unmerged patches (some of which have been reworked, modified, or
rebased). In regards to the continued VMA changes, I think in these, the
delta with regard to the last posting is the bound list was per VM. It
is now global. I've also moved the active list to per VM.
Brand new in the series we take the previous series' context per fd
(with address space) one step further and actually switch the address
spaces when we do context switches. In order to make this happen, the
series continues to chip away at removing the notion of an object only
ever being bound into one address space via the struct
i915_address_space and struct i915_vma data structures which are really
abstractions for a page directory, and current mapped ptes respectively.
The error state is improved since the last series (though still some
work there is probably needed). It also serves to remove the notion of
the aliasing PPGTT since in theory everything bound into the GGTT
shouldn't benefit from an aliasing PPGTT (fact check).
With every context having it's own address space, and every open DRM fd
having it's own context, it's trivial on execbuf to lookup a context and
do the pinning in the proper address space. More importantly, it's
implicit that a context exists, which made this impossible to do
earlier.
*A note on patch ordering:* In order to work this series incrementally, the
final patch ordering is admittedly a little bit strange. I'm more than willing
to rework these as requested, but I'd really prefer not to do really heavy
reordering unless there is a major benefit, or of course to fix bugs.
# What is not in this patch series in the order I think we should handle it
(and I acknowledge some of this stuff is non-trivial):
## Review + QA coverage
## Porting to HSW
It shouldn't be too much extra work, if any, to add support. I haven't looked
into it yet.
## Better vm/ppgtt info in error state collection
In particular, I want to dump all the PTEs at hang, and at the very least the
guilt PTEs. This isn't difficult, and can be done with copypasta from the
existing dumper I have.
## User space and the implications
Now that contexts are valid on all rings, userspace should begin emitting the
context for all rings if it expects both rings to be able to access both
objects in the same offset. The mesa change looks to be just one line which
simplies emits the context for batch->is_blit, I doubt libva is using contexts,
and SNA seems not to. The plan to support mesa will be to do the detection in
libdrm, and go ahead with the simple mesa one liner. I've been using the
oneliner if mesa for a while now, but we will need to support old user space in
the kernel. So there might be a bit of work even on the kernel side here. We
also need some IGT tools test updates. I have messy versions of these locally
already.
## Performance data
I think it doesn't preclude preliminary review of the patches since the main
goal of PPGTT is really abourt security, correctness, and enabling other
things. I will update with some numbers after I work on it a bit more.
## Testing on SNB
If our current code is correct, then I think these patches might work on SNB
as is, but it's untested. There is currently no way to disconnect contexts +
PPGTT from the whole thing; so if this doesn't work - we'll need rework some of
the code. I think it should just entail bringing back aliasing ppgtt, and not
doing the address space switch when switching contexts (aliasing ppgtt will
have a null switch_mm()).
## Soft pin interface
I'd like to defer the discussion until these patches are merged.
## On demand page table allocation
This is a potentially very useful optimization for at least the following
reasons:
* any app using contexts will have an extra set of page tables it isn't using;
wasted memory
* Reduce DCLV to reduce pd fetch latency
* Allows Better use of a switch to default context for low memory situations
(evicting unused page tables for example)
## Per VMA cache levels/control
There are situations in the code where we have to flush the GPU pipeline in
order to change cache levels. This should no longer be the case for unaffected
VMs (I think). The same may be true with domain tracking.
## dmabuf/prime integration
I haven't looked into what's missing to support it. If I'm lucky, it just works.
With that, if you haven't already moved on, chanting tl;dr - all comments
welcome.
---
Ben Widawsky (65):
drm/i915: Remove extra error state NULL
drm/i915: Extract error buffer capture
drm/i915: make PDE|PTE platform specific
drm/i915: Don't clear gtt with 0 entries
drm/i915: Conditionally use guard page based on PPGTT
drm/i915: Use drm_mm for PPGTT PDEs
drm/i915: cleanup context fini
drm/i915: Do a fuller init after reset
drm/i915: Split context enabling from init
drm/i915: destroy i915_gem_init_global_gtt
drm/i915: Embed PPGTT into the context
drm/i915: Unify PPGTT codepaths on gen6+
drm/i915: Move ppgtt initialization down
drm/i915: Tie context to PPGTT
drm/i915: Really share scratch page
drm/i915: Combine scratch members into a struct
drm/i915: Drop dev from pte_encode
drm/i915: Use gtt shortform where possible
drm/i915: Move fbc members out of line
drm/i915: Move gtt and ppgtt under address space umbrella
drm/i915: Move gtt_mtrr to i915_gtt
drm/i915: Move stolen stuff to i915_gtt
drm/i915: Move aliasing_ppgtt
drm/i915: Put the mm in the parent address space
drm/i915: Move active/inactive lists to new mm
drm/i915: Create a global list of vms
drm/i915: Remove object's gtt_offset
drm: pre allocate node for create_block
drm/i915: Getter/setter for object attributes
drm/i915: Create VMAs (part 1)
drm/i915: Create VMAs (part 2) - kill gtt space
drm/i915: Create VMAs (part 3) - plumbing
drm/i915: Create VMAs (part 3.5) - map and fenceable tracking
drm/i915: Create VMAs (part 4) - Error capture
drm/i915: Create VMAs (part 5) - move mm_list
drm/i915: Create VMAs (part 6) - finish error plumbing
drm/i915: create an object_is_active()
drm/i915: Move active to vma
drm/i915: Track all VMAs per VM
drm/i915: Defer request freeing
drm/i915: Clean up VMAs before freeing
drm/i915: Replace has_bsd/blt with a mask
drm/i915: Catch missed context unref earlier
drm/i915: Add a context open function
drm/i915: Permit contexts on all rings
drm/i915: Fix context fini refcounts
drm/i915: Better reset handling for contexts
drm/i915: Create a per file_priv default context
drm/i915: Remove ring specificity from contexts
drm/i915: Track which ring a context ran on
drm/i915: dump error state based on capture
drm/i915: PPGTT should take a ppgtt argument
drm/i915: USE LRI for switching PP_DIR_BASE
drm/i915: Extract mm switching to function
drm/i915: Write PDEs at init instead of enable
drm/i915: Disallow pin with full ppgtt
drm/i915: Get context early in execbuf
drm/i915: Pass ctx directly to switch/hangstat
drm/i915: Actually add the new address spaces
drm/i915: Use multiple VMs
drm/i915: Kill now unused ppgtt_{un,}bind
drm/i915: Add PPGTT dumper
drm/i915: Dump all ppgtt
drm/i915: Add debugfs for vma info per vm
drm/i915: Getparam full ppgtt
Chris Wilson (1):
drm: Optionally create mm blocks from top-to-bottom
drivers/gpu/drm/drm_mm.c | 134 +++---
drivers/gpu/drm/i915/i915_debugfs.c | 215 ++++++++--
drivers/gpu/drm/i915/i915_dma.c | 25 +-
drivers/gpu/drm/i915/i915_drv.c | 57 ++-
drivers/gpu/drm/i915/i915_drv.h | 353 ++++++++++------
drivers/gpu/drm/i915/i915_gem.c | 639 +++++++++++++++++++++--------
drivers/gpu/drm/i915/i915_gem_context.c | 279 +++++++++----
drivers/gpu/drm/i915/i915_gem_debug.c | 11 +-
drivers/gpu/drm/i915/i915_gem_evict.c | 64 +--
drivers/gpu/drm/i915/i915_gem_execbuffer.c | 138 ++++---
drivers/gpu/drm/i915/i915_gem_gtt.c | 541 ++++++++++++++----------
drivers/gpu/drm/i915/i915_gem_stolen.c | 87 ++--
drivers/gpu/drm/i915/i915_gem_tiling.c | 21 +-
drivers/gpu/drm/i915/i915_irq.c | 197 ++++++---
drivers/gpu/drm/i915/i915_trace.h | 38 +-
drivers/gpu/drm/i915/intel_display.c | 40 +-
drivers/gpu/drm/i915/intel_drv.h | 7 -
drivers/gpu/drm/i915/intel_fb.c | 8 +-
drivers/gpu/drm/i915/intel_overlay.c | 26 +-
drivers/gpu/drm/i915/intel_pm.c | 65 +--
drivers/gpu/drm/i915/intel_ringbuffer.c | 32 +-
drivers/gpu/drm/i915/intel_sprite.c | 8 +-
include/drm/drm_mm.h | 147 ++++---
include/uapi/drm/i915_drm.h | 1 +
24 files changed, 2044 insertions(+), 1089 deletions(-)
--
1.8.3.1
