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-rw-r--r--debian/patches-rt/drm-i915-Do-not-disable-preemption-for-resets.patch99
1 files changed, 0 insertions, 99 deletions
diff --git a/debian/patches-rt/drm-i915-Do-not-disable-preemption-for-resets.patch b/debian/patches-rt/drm-i915-Do-not-disable-preemption-for-resets.patch
deleted file mode 100644
index 5869667030..0000000000
--- a/debian/patches-rt/drm-i915-Do-not-disable-preemption-for-resets.patch
+++ /dev/null
@@ -1,99 +0,0 @@
-From: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
-Date: Wed, 5 Jul 2023 10:30:25 +0100
-Subject: [PATCH] drm/i915: Do not disable preemption for resets
-Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.6/older/patches-6.6.7-rt18.tar.xz
-
-Commit ade8a0f59844 ("drm/i915: Make all GPU resets atomic") added a
-preempt disable section over the hardware reset callback to prepare the
-driver for being able to reset from atomic contexts.
-
-In retrospect I can see that the work item at a time was about removing
-the struct mutex from the reset path. Code base also briefly entertained
-the idea of doing the reset under stop_machine in order to serialize
-userspace mmap and temporary glitch in the fence registers (see
-eb8d0f5af4ec ("drm/i915: Remove GPU reset dependence on struct_mutex"),
-but that never materialized and was soon removed in 2caffbf11762
-("drm/i915: Revoke mmaps and prevent access to fence registers across
-reset") and replaced with a SRCU based solution.
-
-As such, as far as I can see, today we still have a requirement that
-resets must not sleep (invoked from submission tasklets), but no need to
-support invoking them from a truly atomic context.
-
-Given that the preemption section is problematic on RT kernels, since the
-uncore lock becomes a sleeping lock and so is invalid in such section,
-lets try and remove it. Potential downside is that our short waits on GPU
-to complete the reset may get extended if CPU scheduling interferes, but
-in practice that probably isn't a deal breaker.
-
-In terms of mechanics, since the preemption disabled block is being
-removed we just need to replace a few of the wait_for_atomic macros into
-busy looping versions which will work (and not complain) when called from
-non-atomic sections.
-
-Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
-Cc: Chris Wilson <chris.p.wilson@intel.com>
-Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
-Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
-Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
-Link: https://lore.kernel.org/r/20230705093025.3689748-1-tvrtko.ursulin@linux.intel.com
-Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
----
- drivers/gpu/drm/i915/gt/intel_reset.c | 12 +++++-------
- 1 file changed, 5 insertions(+), 7 deletions(-)
-
---- a/drivers/gpu/drm/i915/gt/intel_reset.c
-+++ b/drivers/gpu/drm/i915/gt/intel_reset.c
-@@ -164,13 +164,13 @@ static int i915_do_reset(struct intel_gt
- /* Assert reset for at least 20 usec, and wait for acknowledgement. */
- pci_write_config_byte(pdev, I915_GDRST, GRDOM_RESET_ENABLE);
- udelay(50);
-- err = wait_for_atomic(i915_in_reset(pdev), 50);
-+ err = _wait_for_atomic(i915_in_reset(pdev), 50, 0);
-
- /* Clear the reset request. */
- pci_write_config_byte(pdev, I915_GDRST, 0);
- udelay(50);
- if (!err)
-- err = wait_for_atomic(!i915_in_reset(pdev), 50);
-+ err = _wait_for_atomic(!i915_in_reset(pdev), 50, 0);
-
- return err;
- }
-@@ -190,7 +190,7 @@ static int g33_do_reset(struct intel_gt
- struct pci_dev *pdev = to_pci_dev(gt->i915->drm.dev);
-
- pci_write_config_byte(pdev, I915_GDRST, GRDOM_RESET_ENABLE);
-- return wait_for_atomic(g4x_reset_complete(pdev), 50);
-+ return _wait_for_atomic(g4x_reset_complete(pdev), 50, 0);
- }
-
- static int g4x_do_reset(struct intel_gt *gt,
-@@ -207,7 +207,7 @@ static int g4x_do_reset(struct intel_gt
-
- pci_write_config_byte(pdev, I915_GDRST,
- GRDOM_MEDIA | GRDOM_RESET_ENABLE);
-- ret = wait_for_atomic(g4x_reset_complete(pdev), 50);
-+ ret = _wait_for_atomic(g4x_reset_complete(pdev), 50, 0);
- if (ret) {
- GT_TRACE(gt, "Wait for media reset failed\n");
- goto out;
-@@ -215,7 +215,7 @@ static int g4x_do_reset(struct intel_gt
-
- pci_write_config_byte(pdev, I915_GDRST,
- GRDOM_RENDER | GRDOM_RESET_ENABLE);
-- ret = wait_for_atomic(g4x_reset_complete(pdev), 50);
-+ ret = _wait_for_atomic(g4x_reset_complete(pdev), 50, 0);
- if (ret) {
- GT_TRACE(gt, "Wait for render reset failed\n");
- goto out;
-@@ -785,9 +785,7 @@ int __intel_gt_reset(struct intel_gt *gt
- reset_mask = wa_14015076503_start(gt, engine_mask, !retry);
-
- GT_TRACE(gt, "engine_mask=%x\n", reset_mask);
-- preempt_disable();
- ret = reset(gt, reset_mask, retry);
-- preempt_enable();
-
- wa_14015076503_end(gt, reset_mask);
- }