[PATCH 5.15 41/73] drm/i915/gt: Skip TLB invalidations once wedged

Greg Kroah-Hartman
2022-09-02T12:49:35Z

From: Chris Wilson <chris.p.wilson@intel.com>

[ Upstream commit e5a95c83ed1492c0f442b448b20c90c8faaf702b ]

Skip all further TLB invalidations once the device is wedged and
had been reset, as, on such cases, it can no longer process instructions
on the GPU and the user no longer has access to the TLB's in each engine.

So, an attempt to do a TLB cache invalidation will produce a timeout.

That helps to reduce the performance regression introduced by TLB
invalidate logic.

Cc: stable@vger.kernel.org
Fixes: 7938d61591d3 ("drm/i915: Flush TLBs before releasing backing store")
Signed-off-by: Chris Wilson <chris.p.wilson@intel.com>
Cc: Fei Yang <fei.yang@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/5aa86564b9ec5fe7fe605c1dd7de76855401ed73.1658924372.git.mchehab@kernel.org
(cherry picked from commit be0366f168033374a93e4c43fdaa1a90ab905184)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/i915/gt/intel_gt.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
index 3a76000d15bfd..ed8ad3b263959 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt.c
@@ -949,6 +949,9 @@ void intel_gt_invalidate_tlbs(struct intel_gt *gt)
if (I915_SELFTEST_ONLY(gt->awake == -ENODEV))
return;

+ if (intel_gt_is_wedged(gt))
+ return;
+
if (GRAPHICS_VER(i915) == 12) {
regs = gen12_regs;
num = ARRAY_SIZE(gen12_regs);
--
2.35.1