In theory this will have performance and power improvements. Performance
because we don't need to stall when the scanout BO is busy, and power
because we don't have to stall when the BO is busy (and the ring can
even go to sleep if the HW supports it).
v2:
squash 2 patches into 1 (me)
un-inline the enable_semaphores function (Daniel)
remove comment about SNB hangs from i915_gem_object_sync (Chris)
rename intel_enable_semaphores to i915_semaphore_is_enabled (me)
removed page flip comment; "no why" (Chris)
To address other comments from Daniel (irc):
update the comment to say 'vt-d is crap, don't enable semaphores'
- I think you misinterpreted Chris' comment, it already exists.
checking out whether we can pageflip on the render ring on ivb (didn't
work on early silicon)
- We don't want to enable workarounds for early silicon unless we have
to.
- I can't find any references in the docs about this.
optionally use it if the fb is already busy on the render ring
- This should be how the code already worked, unless I am
misunderstanding your meaning.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
By simplifying the rules to calling get_fence when writing to the
through the GTT in a tiled manner, and calling put_fence before writing
to the object through the GTT in a linear manner, the code becomes
clearer and there is less chance of making a mistake.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[danvet: fixed up conflict with ppgtt code and spelling in a new
comment.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Daniel Vetter wrote
First pull request for 3.5-next, slightly large than usual because new
things kept coming in since the last pull for 3.4.
Highlights:
- first batch of hw enablement for vlv (Jesse et al) and hsw (Eugeni). pci
ids are not yet added, and there's still quite a few patches to merge
(mostly modesetting). To make QA easier I've decided to merge this stuff
in pieces.
- loads of cleanups and prep patches spurred by the above. Especially vlv
is a real frankenstein chip, but also hsw is stretching our driver's
code design. Expect more to come in this area for 3.5.
- more gmbus fixes, cleanups and improvements by Daniel Kurtz. Again,
there are more patches needed (and some already queued up), but I wanted
to split this a bit for better testing.
- pwrite/pread rework and retuning. This series has been in the works for
a few months already and a lot of i-g-t tests have been created for it.
Now it's finally ready to be merged. Note that one patch in this series
touches include/pagemap.h, that patch is acked-by akpm.
- reduce mappable pressure and relocation throughput improvements from
Chris.
- mmap offset exhaustion mitigation by Chris Wilson.
- a start at figuring out which codepaths in our messy dri1/ums+gem/kms
driver we actually need to support by bailing out of unsupported case.
The driver now refuses to load without kms on gen6+ and disallows a few
ioctls that userspace never used in certain cases. More of this will
definitely come.
- More decoupling of global gtt and ppgtt.
- Improved dual-link lvds detection by Takashi Iwai.
- Shut up the compiler + plus fix the fallout (Ben)
- Inverted panel brightness handling (mostly Acer manages to break things
in this way).
- Small fixlets and adjustements and some minor things to help debugging.
Regression-wise QA reported quite a few issues on ivb, but all of them
turned out to be hw stability issues which are already fixed in
drm-intel-fixes (QA runs the nightly regression tests on -next alone,
without -fixes automatically merged in). There's still one issue open on
snb, it looks like occlusion query writes are not quite as cache coherent
as we've expected. With some of the pwrite adjustements we can now
reliably hit this. Kernel workaround for it is in the works."
* 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel: (101 commits)
drm/i915: VCS is not the last ring
drm/i915: Add a dual link lvds quirk for MacBook Pro 8,2
drm/i915: make quirks more verbose
drm/i915: dump the DMA fetch addr register on pre-gen6
drm/i915/sdvo: Include YRPB as an additional TV output type
drm/i915: disallow gem init ioctl on ilk
drm/i915: refuse to load on gen6+ without kms
drm/i915: extract gt interrupt handler
drm/i915: use render gen to switch ring irq functions
drm/i915: rip out old HWSTAM missed irq WA for vlv
drm/i915: open code gen6+ ring irqs
drm/i915: ring irq cleanups
drm/i915: add SFUSE_STRAP registers for digital port detection
drm/i915: add WM_LINETIME registers
drm/i915: add WRPLL clocks
drm/i915: add LCPLL control registers
drm/i915: add SSC offsets for SBI access
drm/i915: add port clock selection support for HSW
drm/i915: add S PLL control
drm/i915: add PIXCLK_GATE register
...
Conflicts:
drivers/char/agp/intel-agp.h
drivers/char/agp/intel-gtt.c
drivers/gpu/drm/i915/i915_debugfs.c
The BLT commands on gen2/3 utilize the fence registers and so we cannot
modify any fences for the object whilst those commands are in flight.
Currently we marked tiled commands as occupying a fence, but forgot to
restrict the untiled commands from preventing a fence being assigned
before they were completed.
One side-effect is that we ten have to double check that a fence was
allocated for a fenced buffer during move-to-active.
Reported-by: Jiri Slaby <jirislaby@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=43427
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=47990
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Testcase: i-g-t/tests/gem_tiled_after_untiled_blt
Tested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drm/i915 wants to read/write more than one page in its fastpath
and hence needs to prefault more than PAGE_SIZE bytes.
Add new functions in filemap.h to make that possible.
Also kill a copy&pasted spurious space in both functions while at it.
v2: As suggested by Andrew Morton, add a multipage parameter to both
functions to avoid the additional branch for the pagemap.c hotpath.
My gcc 4.6 here seems to dtrt and indeed reap these branches where not
needed.
v3: Becaus I couldn't find a way around adding a uaddr += PAGE_SIZE to
the filemap.c hotpaths (that the compiler couldn't remove again),
let's go with separate new functions for the multipage use-case.
v4: Adjust comment to CodingStlye and fix spelling.
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We try to avoid writing the relocations through the uncached GTT, if the
buffer is currently in the CPU write domain and so will be flushed out to
main memory afterwards anyway. Also on SandyBridge we can safely write
to the pages in cacheable memory, so long as the buffer is LLC mapped.
In either of these cases, we therefore do not need to force the
reallocation of the buffer into the mappable region of the GTT, reducing
the aperture pressure.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Originally the code tried to allocate a large enough array to perform
the copy using vmalloc, performance wasn't great and throughput was
improved by processing each individual relocation entry separately.
This too is not as efficient as one would desire. A compromise would be
to allocate a single page, or to allocate a few entries on the stack,
and process the copy in batches. The latter gives simpler code and more
consistent performance due to a lack of heuristic.
x11perf -copywinwin10: n450/pnv i3-330m i5-2520m (cpu)
before: 249000 785000 1280000 (80%)
page: 264000 896000 1280000 (65%)
on-stack: 264000 902000 1280000 (67%)
v2: Use 512-bytes of stack for batching rather than allocate a page.
v3: Tidy the code slightly with more descriptive variable names
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
PIPE_CONTROL on snb needs global gtt mappings in place to workaround a
hw gotcha. No other commands need such a workaround. Luckily we can
detect a PIPE_CONTROL commands easily because they have a write_domain
= I915_GEM_DOMAIN_INSTRUCTION (and nothing else has that).
v2: Binding the target of such a reloc into the global gtt actually
works instead of binding the source, which is rather pointless ...
v3: Kill a superflous has_global_gtt_mapping assignement noticed by
Chris Wilson.
Reviewed-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Back-merge from drm-fixes into drm-intel-next to sort out two things:
- interlaced support: -fixes contains a bugfix to correctly clear
interlaced configuration bits in case the bios sets up an interlaced
mode and we want to set up the progressive mode (current kernels
don't support interlaced). The actual feature work to support
interlaced depends upon (and conflicts with) this bugfix.
- forcewake voodoo to workaround missed IRQ issues: -fixes only enabled
this for ivybridge, but some recent bug reports indicate that we
need this on Sandybridge, too. But in a slightly different flavour
and with other fixes and reworks on top. Additionally there are some
forcewake cleanup patches heading to -next that would conflict with
currrent -fixes.
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This adds support to bind/unbind objects and wires it up. Objects are
only put into the ppgtt when necessary, i.e. at execbuf time.
Objects are still unconditionally put into the global gtt.
v2: Kill the quick hack and explicitly pass cache_level to ppgtt_bind
like for the global gtt function. Noticed by Chris Wilson.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
These are all user-trigerable, so tune down their loudness a notch.
For some of these we have i-g-t tests (because they prevent
newly-discovered bugs), without this patches running the test suite
leaves behind a dirty dmesg.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This confuses our domain tracking and can (for gtt write domains) lead
to a subsequent oops.
Tested by tests/gem_exec_bad_domains from i-g-t.
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
In order to correctly account for reserving space in the GTT and fences
for a batch buffer, we need to independently track whether the fence is
pinned due to a fenced GPU access in the batch or whether the buffer is
pinned in the aperture. Currently we count the fenced as pinned if the
buffer has already been seen in the execbuffer. This leads to a false
accounting of available fence registers, causing frequent mass evictions.
Worse, if coupled with the change to make i915_gem_object_get_fence()
report EDADLK upon fence starvation, the batchbuffer can fail with only
one fence required...
Fixes intel-gpu-tools/tests/gem_fenced_exec_thrash
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=38735
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Paul Neumann <paul104x@yahoo.de>
[danvet: Resolve the functional conflict with Jesse Barnes sprite
patches, acked by Chris Wilson on irc.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
... and add a helpr function for the places where we want a flag.
This way we can use ring->id to index into arrays.
v2: Resurrect the missing beautification-space Chris Wilson noted.
I'm moving this space around because I'll reuse ring_str in the next
patch.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Sometimes it may be the case when we idle the gpu or wait on something
we don't actually want to process the retiring list. This patch allows
callers to choose the behavior.
Reviewed-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* 'drm-core-next' of git://people.freedesktop.org/~airlied/linux: (307 commits)
drm/nouveau/pm: fix build with HWMON off
gma500: silence gcc warnings in mid_get_vbt_data()
drm/ttm: fix condition (and vs or)
drm/radeon: double lock typo in radeon_vm_bo_rmv()
drm/radeon: use after free in radeon_vm_bo_add()
drm/sis|via: don't return stack garbage from free_mem ioctl
drm/radeon/kms: remove pointless CS flags priority struct
drm/radeon/kms: check if vm is supported in VA ioctl
drm: introduce drm_can_sleep and use in intel/radeon drivers. (v2)
radeon: Fix disabling PCI bus mastering on big endian hosts.
ttm: fix agp since ttm tt rework
agp: Fix multi-line warning message whitespace
drm/ttm/dma: Fix accounting error when calling ttm_mem_global_free_page and don't try to free freed pages.
drm/ttm/dma: Only call set_pages_array_wb when the page is not in WB pool.
drm/radeon/kms: sync across multiple rings when doing bo moves v3
drm/radeon/kms: Add support for multi-ring sync in CS ioctl (v2)
drm/radeon: GPU virtual memory support v22
drm: make DRM_UNLOCKED ioctls with their own mutex
drm: no need to hold global mutex for static data
drm/radeon/benchmark: common modes sweep ignores 640x480@32
...
Fix up trivial conflicts in radeon/evergreen.c and vmwgfx/vmwgfx_kms.c
These registers are automatically incremented by the hardware during
transform feedback to track where the next streamed vertex output
should go. Unlike the previous generation, which had a packet for
setting the corresponding registers to a defined value, gen7 only has
MI_LOAD_REGISTER_IMM to do so. That's a secure packet (since it loads
an arbitrary register), so we need to do it from the kernel, and it
needs to be settable atomically with the batchbuffer execution so that
two clients doing transform feedback don't stomp on each others'
state.
Instead of building a more complicated interface involcing setting the
registers to a specific value, just set them to 0 when asked and
userland can tweak its pointers accordingly.
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
The docs say this is required for Gen7, and since the bit was added for
Gen6, we are also setting it there pit pf paranoia. Particularly as
Chris points out, if PIPE_CONTROL counts as a 3d state packet.
This was found through doc inspection by Ken and applies to Gen6+;
Reported-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Keith Packard <keithp@keithp.com>
dev_priv keeps track of the current addressing mode that gets set at
execbuffer time. Unfortunately the existing code was doing this before
acquiring struct_mutex which leaves a race with another thread also
doing an execbuffer. If that wasn't bad enough, relocate_slow drops
struct_mutex which opens a much more likely error where another thread
comes in and modifies the state while relocate_slow is being slow.
The solution here is to just defer setting this state until we
absolutely need it, and we know we'll have struct_mutex for the
remainder of our code path.
v2: Keith noticed a bug in the original patch.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Keith Packard <keithp@keithp.com>
Semaphores still cause problems on some machines:
> From Udo Steinberg:
>
> With Linux-3.2-rc6 I'm frequently seeing GPU hangs when large amounts of
> text scroll in an xterm, such as when extracting a tar archive. Such as this
> one (note the timestamps):
>
> I can reproduce it fairly easily with something
> as simple as:
>
> while true; do dmesg; done
This patch turns them off on SNB while leaving them on for IVB.
Reported-by: Udo Steinberg <udo@hypervisor.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Eugeni Dodonov <eugeni@dodonov.net>
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds a default setting for semaphores parameter, and enables
semaphores by default on IVB.
For now, as semaphores interaction with VTd causes random issues on
SNB, we do not enable them by default. But they can still be enabled
via the semaphores=1 kernel parameter.
v2: enables semaphores on SNB when IO remapping is disabled, with base
on Keith Packard patch.
CC: Daniel Vetter <daniel.vetter@ffwll.ch>
CC: Ben Widawsky <ben@bwidawsk.net>
CC: Keith Packard <keithp@keithp.com>
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
CC: Chris Wilson <chris@chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=42696
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=40564
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=41353
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=38862
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
While I think the previous code is correct, it was hard to follow and
hard to debug. Since we already have a ring abstraction, might as well
use it to handle the semaphore updates and compares.
I don't expect this code to make semaphores better or worse, but you
never know...
v2:
Remove magic per Keith's suggestions.
Ran Daniel's gem_ring_sync_loop test on this.
v3:
Ignored one of Keith's suggestions.
v4:
Removed some bloat per Daniel's recommendation.
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Keith Packard <keithp@keithp.com>
This reverts commit 4a684a4117.
Userland has always been required to set the object's domain to GTT
before using it through a GTT mapping, it's not something that the
kernel is supposed to enforce. (The pagefault support is so that we
can handle multiple mappings without userland having to pin across
them, not so that userland can use GTT after GPU domains without
telling the kernel).
Fixes 19.2% +/- 0.8% (n=6) performance regression in cairo-gl
firefox-talos-gfx on my T420 latop.
Signed-off-by: Keith Packard <keithp@keithp.com>
Along the fast path for relocation handling, we attempt to copy directly
from the user data structures whilst holding our mutex. This causes
lockdep to warn about circular lock dependencies if we need to pagefault
the user pages. [Since when handling a page fault on a mmapped bo, we
need to acquire the struct mutex whilst already holding the mm
semaphore, it is then verboten to acquire the mm semaphore when already
holding the struct mutex. The likelihood of the user passing in the
relocations contained in a GTT mmaped bo is low, but conceivable for
extreme pathology.] In order to force the mm to return EFAULT rather
than handle the pagefault, we therefore need to disable pagefaults
across the relocation fast path.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Andi Kleen narrowed his GPU hangs on his Sugar Bay (SNB desktop) rev 09
down to the use of GPU semaphores, and we already know that they appear
broken up to Huron River (mobile) rev 08. (I'm optimistic that disabling
GPU semaphores is simply hiding another bug by the latency and
side-effects of the additional device interaction it introduces...)
However, use of semaphores is a massive performance improvement... Only
as long as the system remains stable. Enable at your peril.
Reported-by: Andi Kleen <andi-fd@firstfloor.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=33921
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
This seems to be running stably on my test laptop, so hopefully the
reported hangs where just symptoms of other bugs.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Userspace has a legitimate requirement to use a delta that points to
outside of the target bo, and so we need to enable this. (As this is an
abi break, albeit a relaxation of the current restrictions, mark the change
with a new flag.)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
The code paths for modesetting are growing in complexity as we may need
to move the buffers around in order to fit the scanout in the aperture.
Therefore we face a choice as to whether to thread the interruptible status
through the entire pinning and unbinding code paths or to add a flag to
the device when we may not be interrupted by a signal. This does the
latter and so fixes a few instances of modesetting failures under stress.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
As we just need a temporary array whilst performing the relocations for
the execbuffer, first attempt to allocate using kmalloc even if it is
not of order page-0. This avoids the overhead of remapping the
discontiguous array and so gives a moderate boost to execution
throughput.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Dave Airlie spotted that we had a potential bug should we ever rearrange
the drm_i915_gem_object so not the base drm_gem_object was not its first
member. He noticed that we often convert the return of
drm_gem_object_lookup() immediately into drm_i915_gem_object and then
check the result for nullity. This is only valid when the base object is
the first member and so the superobject has the same address. Play safe
instead and use the compiler to convert back to the original return
address for sanity testing.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
A lot of minor tweaks to fix the tracepoints, improve the outputting for
ftrace, and to generally make the tracepoints useful again. It is a start
and enough to begin identifying performance issues and gaps in our
coverage.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
There are I915_NUM_RINGS-1 inter-ring synchronisation counters, but we
were clearing I915_NUM_RINGS of them. Oops.
Reported-by: Jiri Slaby <jirislaby@gmail.com>
Tested-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Move code around and invoke iomem annotation in a few more places in
order to silence sparse. Still a few more iomem annotations to go...
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Hopefully, this is a temporary measure whilst the root cause is
understood. At the moment, we experience a hard hang whilst looping
urbanterror that has been identified as a result of the use of
semaphores, but so far only on SNB mobile.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=32752
Tested-by: mengmeng.meng@intel.com
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
After reordering the sequence of relocating objects, commit 6fe4f1404,
we can no longer rely on seeing all reloc targets prior to performing
the relocation. As a result we were ignoring the need to flush objects
from the render cache and invalidate the sampler caches, resulting in
rendering glitches. So we need to clear the relocation domains earlier.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
On the fault path, commit 6fe4f140 introduction a regression whereby it
changed the sequence of the objects but continued to use the original
ordering of relocation entries. The result was that incorrect GTT offsets
were being fed into the execbuffer causing lots of misrendering and
potential hangs.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
As the mappable portion of the aperture is always a small subset at the
start of the GTT, it is allocated preferentially by drm_mm. This is
useful in case we ever need to map an object later. However, if you have
a large object that can consume the entire mappable region of the
GTT this prevents the batchbuffer from fitting and so causing an error.
Instead allocate all those that require a mapping up front in order to
improve the likelihood of finding sufficient space to bind them.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Before releasing the lock in order to copy the relocation list from user
pages, we need to drop all the object references as another thread may
usurp and execute another batchbuffer before we reacquire the lock.
However, the code was buggy and failed to clear the list...
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
We need to ensure that writes through the GTT land before any
modification to the MMIO registers and so must impose a mandatory write
barrier when flushing the GTT domain. This was revealed by relaxing the
write ordering by experimentally mapping the registers and the GATT as
write-combining.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
The relative-to-general state default is useless as it means having to
rewrite the streaming kernels for each batch. Relative-to-surface is
more useful, as that stream usually needs to be rewritten for each
batch. And absolute addressing mode, vital if you start streaming
state, is also only available by adjusting the register...
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
As we provide a list of all objects that will be accessed from the
batchbuffer, we can build a lut of the handles associated with those
objects for this invocation and use that to avoid the overhead of
looking up those objects again for every relocation.
The cost of building and searching a small hash table is much less than
that of acquiring a spinlock, searching a radix tree and manipulating an
atomic refcnt per relocation.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Userspace should not have been declaring that it needed fenced GPU
access with gen4+ as those GPUs have no fenced commands, but to be on
the safe side it is easier to ignore userspace in case they did.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
The bulk of the change is to convert the growing list of rings into an
array so that the relationship between the rings and the semaphore sync
registers can be easily computed.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
With this change, every batchbuffer can use all available fences (save
pinned and scanout, of course) without ever stalling the gpu!
In theory. Currently the actual pipelined update of the register is
disabled due to some stability issues. However, just the deferred update
is a significant win.
Based on a series of patches by Daniel Vetter.
The premise is that before every access to a buffer through the GTT we
have to declare whether we need a register or not. If the access is by
the GPU, a pipelined update to the register is made via the ringbuffer,
and we track the last seqno of the batches that access it. If by the
CPU we wait for the last GPU access and update the register (either
to clear or to set it for the current buffer).
One advantage of being able to pipeline changes is that we can defer the
actual updating of the fence register until we first need to access the
object through the GTT, i.e. we can eliminate the stall on set_tiling.
This is important as the userspace bo cache does not track the tiling
status of active buffers which generate frequent stalls on gen3 when
enabling tiling for an already bound buffer.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This makes the various rings more consistent by removing the anomalous
handing of the rendering ring execbuffer dispatch.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
As the error occurred on the current object, it means that its state was
not changed and so it should be excluded from the unwind.
Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Besides the minimal improvement in reducing the execbuffer overhead, the
real benefit is clarifying a few routines.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
A number of dragons have been seen lurking within the execbuffer code.
The first step is then to isolate them from the rest and begin to
scrutinise them in depth. Suggested by Daniel Vetter.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Ben Widawsky