We are not allowed to touch the GTT entries underneath an atomic section,
as they take a rpm wakelock (which is illegal from atomic context) and
in the near future acquiring the DMA address for a page within an object
may sleep for an allocation. This makes the current shortcircuit in
relocation_iomap() for performing a second relocation on an adjacent page
illegal, and we need to release the atomic iomapping, lookup the DMA,
insert it into the GTT before reentering the atomic iomap section.
As it happens, this is precisely what we do on if we are using an
iomapping over the full object and not just a single page and by
removing the shortcut, we do the right thing.
Fixes: 9c870d0367 ("drm/i915: Use RPM as the barrier for controlling...")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028142756.3850-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
- first slice of the gvt device model (Zhenyu et al)
- compression support for gpu error states (Chris)
- sunset clause on gpu errors resulting in dmesg noise telling users
how to report them
- .rodata diet from Tvrtko
- switch over lots of macros to only take dev_priv (Tvrtko)
- underrun suppression for dp link training (Ville)
- lspcon (hmdi 2.0 on skl/bxt) support from Shashank Sharma, polish
from Jani
- gen9 wm fixes from Paulo&Lyude
- updated ddi programming for kbl (Rodrigo)
- respect alternate aux/ddc pins (from vbt) for all ddi ports (Ville)
* tag 'drm-intel-next-2016-10-24' of git://anongit.freedesktop.org/drm-intel: (227 commits)
drm/i915: Update DRIVER_DATE to 20161024
drm/i915: Stop setting SNB min-freq-table 0 on powersave setup
drm/i915/dp: add lane_count check in intel_dp_check_link_status
drm/i915: Fix whitespace issues
drm/i915: Clean up DDI DDC/AUX CH sanitation
drm/i915: Respect alternate_ddc_pin for all DDI ports
drm/i915: Respect alternate_aux_channel for all DDI ports
drm/i915/gen9: Remove WaEnableYV12BugFixInHalfSliceChicken7
drm/i915: KBL - Recommended buffer translation programming for DisplayPort
drm/i915: Move down skl/kbl ddi iboost and n_edp_entires fixup
drm/i915: Add a sunset clause to GPU hang logging
drm/i915: Stop reporting error details in dmesg as well as the error-state
drm/i915/gvt: do not ignore return value of create_scratch_page
drm/i915/gvt: fix spare warnings on odd constant _Bool cast
drm/i915/gvt: mark symbols static where possible
drm/i915/gvt: fix sparse warnings on different address spaces
drm/i915/gvt: properly access enabled intel_engine_cs
drm/i915/gvt: Remove defunct vmap_batch()
drm/i915/gvt: Use common mapping routines for shadow_bb object
drm/i915/gvt: Use common mapping routines for indirect_ctx object
...
When handling execbuf relocations, we play a delicate dance with
pagefault. We first try to access the user pages underneath our
struct_mutex. However, if those pages were inside a GEM object, we may
trigger a pagefault and deadlock as i915_gem_fault() tries to
recursively acquire struct_mutex. Instead, we choose to disable
pagefaulting around the copy_from_user whilst inside the struct_mutex
and handle the EFAULT by falling back to a copy outside the
struct_mutex.
We however presumed that disabling pagefaults would be expensive. It is
just an operation on the local current task. Cheap enough that we can
restrict the disable/enable to the critical section around the copy, and
so avoid having to handle the atomic sections within the relocation
handling itself.
v2: Just illustrate the broken error handling rather than argue why it
is safer to ignore it, for now.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161018120251.25043-4-chris@chris-wilson.co.uk
With the possibility of addition of many more number of rings in future,
the drm_i915_private structure could bloat as an array, of type
intel_engine_cs, is embedded inside it.
struct intel_engine_cs engine[I915_NUM_ENGINES];
Though this is still fine as generally there is only a single instance of
drm_i915_private structure used, but not all of the possible rings would be
enabled or active on most of the platforms. Some memory can be saved by
allocating intel_engine_cs structure only for the enabled/active engines.
Currently the engine/ring ID is kept static and dev_priv->engine[] is simply
indexed using the enums defined in intel_engine_id.
To save memory and continue using the static engine/ring IDs, 'engine' is
defined as an array of pointers.
struct intel_engine_cs *engine[I915_NUM_ENGINES];
dev_priv->engine[engine_ID] will be NULL for disabled engine instances.
There is a text size reduction of 928 bytes, from 1028200 to 1027272, for
i915.o file (but for i915.ko file text size remain same as 1193131 bytes).
v2:
- Remove the engine iterator field added in drm_i915_private structure,
instead pass a local iterator variable to the for_each_engine**
macros. (Chris)
- Do away with intel_engine_initialized() and instead directly use the
NULL pointer check on engine pointer. (Chris)
v3:
- Remove for_each_engine_id() macro, as the updated macro for_each_engine()
can be used in place of it. (Chris)
- Protect the access to Render engine Fault register with a NULL check, as
engine specific init is done later in Driver load sequence.
v4:
- Use !!dev_priv->engine[VCS] style for the engine check in getparam. (Chris)
- Kill the superfluous init_engine_lists().
v5:
- Cleanup the intel_engines_init() & intel_engines_setup(), with respect to
allocation of intel_engine_cs structure. (Chris)
v6:
- Rebase.
v7:
- Optimize the for_each_engine_masked() macro. (Chris)
- Change the type of 'iter' local variable to enum intel_engine_id. (Chris)
- Rebase.
v8: Rebase.
v9: Rebase.
v10:
- For index calculation use engine ID instead of pointer based arithmetic in
intel_engine_sync_index() as engine pointers are not contiguous now (Chris)
- For appropriateness, rename local enum variable 'iter' to 'id'. (Joonas)
- Use for_each_engine macro for cleanup in intel_engines_init() and remove
check for NULL engine pointer in cleanup() routines. (Joonas)
v11: Rebase.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476378888-7372-1-git-send-email-akash.goel@intel.com
Pull drm updates from Dave Airlie:
"Core:
- Fence destaging work
- DRIVER_LEGACY to split off legacy drm drivers
- drm_mm refactoring
- Splitting drm_crtc.c into chunks and documenting better
- Display info fixes
- rbtree support for prime buffer lookup
- Simple VGA DAC driver
Panel:
- Add Nexus 7 panel
- More simple panels
i915:
- Refactoring GEM naming
- Refactored vma/active tracking
- Lockless request lookups
- Better stolen memory support
- FBC fixes
- SKL watermark fixes
- VGPU improvements
- dma-buf fencing support
- Better DP dongle support
amdgpu:
- Powerplay for Iceland asics
- Improved GPU reset support
- UVD/VEC powergating support for CZ/ST
- Preinitialised VRAM buffer support
- Virtual display support
- Initial SI support
- GTT rework
- PCI shutdown callback support
- HPD IRQ storm fixes
amdkfd:
- bugfixes
tilcdc:
- Atomic modesetting support
mediatek:
- AAL + GAMMA engine support
- Hook up gamma LUT
- Temporal dithering support
imx:
- Pixel clock from devicetree
- drm bridge support for LVDS bridges
- active plane reconfiguration
- VDIC deinterlacer support
- Frame synchronisation unit support
- Color space conversion support
analogix:
- PSR support
- Better panel on/off support
rockchip:
- rk3399 vop/crtc support
- PSR support
vc4:
- Interlaced vblank timing
- 3D rendering CPU overhead reduction
- HDMI output fixes
tda998x:
- HDMI audio ASoC support
sunxi:
- Allwinner A33 support
- better TCON support
msm:
- DT binding cleanups
- Explicit fence-fd support
sti:
- remove sti415/416 support
etnaviv:
- MMUv2 refactoring
- GC3000 support
exynos:
- Refactoring HDMI DCC/PHY
- G2D pm regression fix
- Page fault issues with wait for vblank
There is no nouveau work in this tree, as Ben didn't get a pull
request in, and he was fighting moving to atomic and adding mst
support, so maybe best it waits for a cycle"
* tag 'drm-for-v4.9' of git://people.freedesktop.org/~airlied/linux: (1412 commits)
drm/crtc: constify drm_crtc_index parameter
drm/i915: Fix conflict resolution from backmerge of v4.8-rc8 to drm-next
drm/i915/guc: Unwind GuC workqueue reservation if request construction fails
drm/i915: Reset the breadcrumbs IRQ more carefully
drm/i915: Force relocations via cpu if we run out of idle aperture
drm/i915: Distinguish last emitted request from last submitted request
drm/i915: Allow DP to work w/o EDID
drm/i915: Move long hpd handling into the hotplug work
drm/i915/execlists: Reinitialise context image after GPU hang
drm/i915: Use correct index for backtracking HUNG semaphores
drm/i915: Unalias obj->phys_handle and obj->userptr
drm/i915: Just clear the mmiodebug before a register access
drm/i915/gen9: only add the planes actually affected by ddb changes
drm/i915: Allow PCH DPLL sharing regardless of DPLL_SDVO_HIGH_SPEED
drm/i915/bxt: Fix HDMI DPLL configuration
drm/i915/gen9: fix the watermark res_blocks value
drm/i915/gen9: fix plane_blocks_per_line on watermarks calculations
drm/i915/gen9: minimum scanlines for Y tile is not always 4
drm/i915/gen9: fix the WaWmMemoryReadLatency implementation
drm/i915/kbl: KBL also needs to run the SAGV code
...
* the only remaining callers of "short" fault-ins are just as happy with generic
variants (both in lib/iov_iter.c); switch them to multipage variants, kill the
"short" ones
* rename the multipage variants to now available plain ones.
* get rid of compat macro defining iov_iter_fault_in_multipage_readable by
expanding it in its only user.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The single largest factor in the overhead of parsing the commands is the
setup of the virtual mapping to provide a continuous block for the batch
buffer. If we keep those vmappings around (against the better judgement
of mm/vmalloc.c, which we offset by handwaving and looking suggestively
at the shrinker) we can dramatically improve the performance of the
parser for small batches (such as media workloads). Furthermore, we can
use the prepare shmem read/write functions to determine how best we
need to clflush the range (rather than every page of the object).
The impact of caching both src/dst vmaps is +80% on ivb and +140% on byt
for the throughput on small batches. (Caching just the dst vmap and
iterating over the src, doing a page by page copy is roughly 5% slower
on both platforms. That may be an acceptable trade-off to eliminate one
cached vmapping, and we may be able to reduce the per-page copying overhead
further.) For *this* simple test case, the cmdparser is now within a
factor of 2 of ideal performance.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160818161718.27187-33-chris@chris-wilson.co.uk
With the introduction of the reloc page cache, we are just one step away
from refactoring the relocation write functions into one. Not only does
it tidy the code (slightly), but it greatly simplifies the control logic
much to gcc's satisfaction.
v2: Add selftests to document the relationship between the clflush
flags, the KMAP bit and packing into the page-aligned pointer.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160818161718.27187-13-chris@chris-wilson.co.uk
When doing relocations, we have to obtain a mapping to the page
containing the target address. This is either a kmap or iomap depending
on GPU and its cache coherency. Neighbouring relocation entries are
typically within the same page and so we can cache our kmapping between
them and avoid those pesky TLB flushes.
Note that there is some sleight-of-hand in how the slow relocate works
as the reloc_entry_cache implies pagefaults disabled (as we are inside a
kmap_atomic section). However, the slow relocate code is meant to be the
fallback from the atomic fast path failing. Fortunately it works as we
already have performed the copy_from_user for the relocation array (no
more pagefaults there) and the kmap_atomic cache is enabled after we
have waited upon an active buffer (so no more sleeping in atomic).
Magic!
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160818161718.27187-7-chris@chris-wilson.co.uk
We are motivated to avoid using a bitfield for obj->active for a couple
of reasons. Firstly, we wish to document our lockless read of obj->active
using READ_ONCE inside i915_gem_busy_ioctl() and that requires an
integral type (i.e. not a bitfield). Secondly, gcc produces abysmal code
when presented with a bitfield and that shows up high on the profiles of
request tracking (mainly due to excess memory traffic as it converts
the bitfield to a register and back and generates frequent AGI in the
process).
v2: BIT, break up a long line in compute the other engines, new paint
for i915_gem_object_is_active (now i915_gem_object_get_active).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-23-git-send-email-chris@chris-wilson.co.uk
Our GPUs impose certain requirements upon buffers that depend upon how
exactly they are used. Typically this is expressed as that they require
a larger surface than would be naively computed by pitch * height.
Normally such requirements are hidden away in the userspace driver, but
when we accept pointers from strangers and later impose extra conditions
on them, the original client allocator has no idea about the
monstrosities in the GPU and we require the userspace driver to inform
the kernel how many padding pages are required beyond the client
allocation.
v2: Long time, no see
v3: Try an anonymous union for uapi struct compatibility
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-7-git-send-email-chris@chris-wilson.co.uk
This reimplements the denial-of-service protection against igt from
commit 227f782e46 ("drm/i915: Retire requests before creating a new
one") and transfers the stall from before each batch into get_pages().
The issue is that the stall is increasing latency between batches which
is detrimental in some cases (especially coupled with execlists) to
keeping the GPU well fed. Also we have made the observation that retiring
requests can of itself free objects (and requests) and therefore makes
a good first step when shrinking.
v2: Recycle objects prior to i915_gem_object_get_pages()
v3: Remove the reference to the ring from i915_gem_requests_ring() as it
operates on an intel_engine_cs.
v4: Since commit 9b5f4e5ed6 ("drm/i915: Retire oldest completed request
before allocating next") we no longer need the safeguard to retire
requests before get_pages(). We no longer see the huge latencies when
hitting the shrinker between allocations.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-4-git-send-email-chris@chris-wilson.co.uk
Hook the vma itself into the i915_gem_request_retire() so that we can
accurately track when a solitary vma is inactive (as opposed to having
to wait for the entire object to be idle). This improves the interaction
when using multiple contexts (with full-ppgtt) and eliminates some
frequent list walking when retiring objects after a completed request.
A side-effect is that we get an active vma reference for free. The
consequence of this is shown in the next patch...
v2: Update inline names to be consistent with
i915_gem_object_get_active()
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-25-git-send-email-chris@chris-wilson.co.uk
This patch is broken out of the next just to remove the code motion from
that patch and make it more readable. What we do here is move the
i915_vma_move_to_active() to i915_gem_execbuffer.c and put the three
stages (read, write, fenced) together so that future modifications to
active handling are all located in the same spot. The importance of this
is so that we can more simply control the order in which the requests
are place in the retirement list (i.e. control the order at which we
retire and so control the lifetimes to avoid having to hold onto
references).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-24-git-send-email-chris@chris-wilson.co.uk
In the next patch, request tracking is made more generic and for that we
need a new expanded struct and to separate out the logic changes from
the mechanical churn, we split out the structure renaming into this
patch.
v2: Writer's block. Add some spiel about why we track requests.
v3: Now i915_gem_active.
v4: Now with i915_gem_active_set() for attaching to the active request.
v5: Use i915_gem_active_set() from inside the retirement handlers
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-10-git-send-email-chris@chris-wilson.co.uk