From 9c4ddd6abc204e440549bff1859a428548d90686 Mon Sep 17 00:00:00 2001
From: Matthew Brost <matthew.brost@intel.com>
Date: Wed, 21 Jul 2021 14:50:52 -0700
Subject: drm/i915/guc: Disable engine barriers with GuC during unpin
Git-commit: b8b183abca5108ad67b0b9e23b6d407347bc4aa8
Patch-mainline: v5.15-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
Disable engine barriers for unpinning with GuC. This feature isn't
needed with the GuC as it disables context scheduling before unpinning
which guarantees the HW will not reference the context. Hence it is
not necessary to defer unpinning until a kernel context request
completes on each engine in the context engine mask.
Cc: John Harrison <john.c.harrison@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210721215101.139794-10-matthew.brost@intel.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/gt/intel_context.c | 2 +-
drivers/gpu/drm/i915/gt/selftest_context.c | 10 ++++++++++
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
index dca25b6569aa..cba2521d26f4 100644
--- a/drivers/gpu/drm/i915/gt/intel_context.c
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -80,7 +80,7 @@ static int intel_context_active_acquire(struct intel_context *ce)
__i915_active_acquire(&ce->active);
- if (intel_context_is_barrier(ce))
+ if (intel_context_is_barrier(ce) || intel_engine_uses_guc(ce->engine))
return 0;
/* Preallocate tracking nodes */
diff --git a/drivers/gpu/drm/i915/gt/selftest_context.c b/drivers/gpu/drm/i915/gt/selftest_context.c
index 26685b927169..fa7b99a671dd 100644
--- a/drivers/gpu/drm/i915/gt/selftest_context.c
+++ b/drivers/gpu/drm/i915/gt/selftest_context.c
@@ -209,7 +209,13 @@ static int __live_active_context(struct intel_engine_cs *engine)
* This test makes sure that the context is kept alive until a
* subsequent idle-barrier (emitted when the engine wakeref hits 0
* with no more outstanding requests).
+ *
+ * In GuC submission mode we don't use idle barriers and we instead
+ * get a message from the GuC to signal that it is safe to unpin the
+ * context from memory.
*/
+ if (intel_engine_uses_guc(engine))
+ return 0;
if (intel_engine_pm_is_awake(engine)) {
pr_err("%s is awake before starting %s!\n",
@@ -357,7 +363,11 @@ static int __live_remote_context(struct intel_engine_cs *engine)
* on the context image remotely (intel_context_prepare_remote_request),
* which inserts foreign fences into intel_context.active, does not
* clobber the idle-barrier.
+ *
+ * In GuC submission mode we don't use idle barriers.
*/
+ if (intel_engine_uses_guc(engine))
+ return 0;
if (intel_engine_pm_is_awake(engine)) {
pr_err("%s is awake before starting %s!\n",
--
2.38.1