drm/i915: Do one shot unclaimed mmio detection less frequently
authorMika Kuoppala <mika.kuoppala@linux.intel.com>
Wed, 16 Dec 2015 07:26:48 +0000 (09:26 +0200)
committerMika Kuoppala <mika.kuoppala@intel.com>
Fri, 8 Jan 2016 11:13:50 +0000 (13:13 +0200)
commit7571494004d88249bcee2a20fa74cb50753676fe
tree1f1e51b4ad0482bad782071eebdc64b9aa2b1bcd
parent55ec45c2ced1a4b1e7cd2e7e306101f328958760
drm/i915: Do one shot unclaimed mmio detection less frequently

We have done unclaimed register access check in normal
(mmio_debug=0) mode once per write. This adds probability
of finding the exact sequence where we did the bad access, but
also adds burden to each write.

As we have mmio_debug available for more fine grained analysis,
give up accuracy of detecting correct spot at the first occurrence
by doing the one shot detection and arming of mmio_debug in hangcheck
and in modeset. This removes the write path performance burden.

v2: Remove gratuitous DRM_DEBUG and return value, comments (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450250808-14864-1-git-send-email-mika.kuoppala@intel.com
drivers/gpu/drm/i915/i915_drv.h
drivers/gpu/drm/i915/i915_irq.c
drivers/gpu/drm/i915/intel_display.c
drivers/gpu/drm/i915/intel_uncore.c