The SET_TILING is pernicious in that it overwrites the input arguments
following an error in order to report the current tiling state of the
buffer. This caught us by surprise as we then fed those arguments back
into to the ioctl unmodified following an EINTR and so the kernel then
reported success for the no-op. We interpreted this success as meaning
that the tiling on the buffer had changed so updated our state and
started using the buffer incorrectly in the new tiled/untiled manner.
This lead to all sorts of random corruption and GPU hangs, even though
the batch buffers would look sane (when the GPU had not wandered off
into forbidden territory).
References:
Bug 25475 - [i915] Xorg crash / Execbuf while wedged
http://bugs.freedesktop.org/show_bug.cgi?id=25475
Bug 25554 - i830_uxa_prepare_access: gtt bo map failed: Input/output error
http://bugs.freedesktop.org/show_bug.cgi?id=25554
(And probably every other weird bug in the last few months.)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
As the kernel reports the total number of fences, we must guess how many
fences are likely to be pinned. In the typical system these will be only
used by the scanout buffers, of which there may be one per pipe, and any
number of manually pinned fenced buffers. So take a conservative guess
and reserve two fences for use by the system.
Note this reduces the number of fences to 3 for i915 and prior.
Reference:
http://bugs.freedesktop.org/show_bug.cgi?id=25911
The latest intel driver 2.10.0 causes kernel oops and system hangs
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Don't store the error return in bo_gem->gtt_virtual or else we will
attempt to use that as a valid pointer in future mappings.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
This removes the foremost prolific user of mutexes in libdrm_intel.so.
The other uses of the bufmgr_gem->mutex to serial access to individual
bos are currently required by Mesa, and are far less frequent.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[anholt: This chunk looks good...]
Acked-by: Eric Anholt <eric@anholt.net>
This has the unfortunate behaviour of releasing our malloc cache, but
the alternative is for X to consume a couple of gigabytes of ram and
die during testing. Fortunately the extra mallocs have little impact on
performance whereas avoiding swap and death, lots.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Instead of forcing the caller to check after every emit_reloc(), we can
flag the object as being in error, propagating that error upwards through
the relocation tree, and failing the eventual batch buffer execution.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
EAGAIN cannot be raised by the current code, but the system call maybe
interrupted and so return EINTR.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Hitting this error lead to a segfault:
intel_bufmgr_gem.c:919: Error mapping buffer 48607 (pixmap):
Cannot allocate memory.
because the errno was reused as the function return value after being
reset by the fprintf(), so caller thought the mapping had succeeded. The
convention established by libdrm is that the return value is the
negative errno and that uses of libdrm cannot trust the value of errno
afterwards, but must use the return code.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Buffers on the relocation tree are guarded by the reference to the batch
object and so do not need an extra reference whilst constructing the
list of execution buffer objects.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Having been bitten by a missing EINTR check during mmap_gtt(), I thought
it prudent to add some more protection around the ioctls.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
This allows us to keep the assert added in the previous commit that we do
not modify the tree_reloc_size after inserting the buffer into a relocation
tree, which was being hit here:
#0 0xb78c2424 in __kernel_vsyscall ()
#1 0xb74f6401 in raise () from /lib/libc.so.6
#2 0xb74f7b42 in abort () from /lib/libc.so.6
#3 0xb74ef5a8 in __assert_fail () from /lib/libc.so.6
#4 0xb737e78b in drm_intel_bo_gem_set_in_aperture_size (bufmgr_gem=<value optimized out>, bo_gem=0x6) at intel_bufmgr_gem.c:373
#5 0xb737f519 in drm_intel_gem_bo_set_tiling (bo=0xa1030a0, tiling_mode=0xbff6c85c, stride=0) at intel_bufmgr_gem.c:1386
#6 0xb737f67f in drm_intel_gem_bo_unreference_final (bo=0xa1030a0, time=<value optimized out>) at intel_bufmgr_gem.c:768
#7 0xb737f5e3 in drm_intel_gem_bo_unreference_locked_timed (bo=0xa1e50d0, time=<value optimized out>) at intel_bufmgr_gem.c:805
#8 drm_intel_gem_bo_unreference_final (bo=0xa1e50d0, time=<value optimized out>) at intel_bufmgr_gem.c:756
#9 0xb737fcbb in drm_intel_gem_bo_unreference (bo=0xa1e50d0) at intel_bufmgr_gem.c:821
#10 0xb737b4e6 in drm_intel_bo_unreference (bo=0x0) at intel_bufmgr.c:80
#11 0xb7325625 in intel_batch_flush (scrn=0x9d91f78, flush=1) at i830_batchbuffer.c:200
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
For the older chipsets, i.e. pre-i965, which have severe alignment
restrictions for tiled buffers we need to pessimistically assume that we
will waste the size of buffer to meet those alignment constraints.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
If the kernel immediately frees the backing store for a buffer when
marking it purgeable, then there is not point adding to the cache. Free
it immediately, instead.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Eric Anholt
Chris Wilson
Dave Airlie
Kristian Høgsberg