linux/drivers/gpu
Chris Wilson 9107e9d227 drm/i915: Only slightly increment hangcheck score if we succesfully kick a ring
After kicking a ring, it should be free to make progress again and so
should not be accused of being stuck until hangcheck fires once more. In
order to catch a denial-of-service within a batch or across multiple
batches, we still do increment the hangcheck score - just not as
severely so that it takes multiple kicks to fail.

This should address part of Ben's justified criticism of

commit 05407ff889
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Thu May 30 09:04:29 2013 +0300

    drm/i915: detect hang using per ring hangcheck_score

"There's also another corner case on the kick. If the seqno = 2
(though not stuck), and on the 3rd hangcheck, the ring is stuck, and
we try to kick it... we don't actually try to find out if the kick
helped."

v2: Make sure we catch DoS attempts with batches full of invalid WAITs.
v3: Preserve the ability to detect loops by always charging the ring
    if it is busy on the same request.
v4: Make sure we queue another check if on a new batch

References: https://bugs.freedesktop.org/show_bug.cgi?id=65394
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-06-11 11:44:00 +02:00
..
drm drm/i915: Only slightly increment hangcheck score if we succesfully kick a ring 2013-06-11 11:44:00 +02:00
host1x drivers/gpu/host1x/drm: don't check resource with devm_ioremap_resource 2013-05-18 11:55:30 +02:00
vga fbcon: fix locking harder 2013-02-08 12:02:43 +10:00
Makefile gpu: host1x: Add host1x driver 2013-04-22 12:32:40 +02:00