Re: [PATCH 03/23] drm/i915: Remove lrc default desc from GEM context

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 23/07/2019 19:38, Chris Wilson wrote:
We only compute the lrc_descriptor() on pinning the context, i.e.
infrequently, so we do not benefit from storing the template as the
addressing mode is also fixed for the lifetime of the intel_context.

Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
---
  drivers/gpu/drm/i915/gem/i915_gem_context.c   | 28 ++-----------------
  .../gpu/drm/i915/gem/i915_gem_context_types.h |  2 --
  drivers/gpu/drm/i915/gt/intel_lrc.c           | 12 +++++---
  drivers/gpu/drm/i915/gvt/scheduler.c          |  3 --
  4 files changed, 10 insertions(+), 35 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index b28c7ca681a8..1b3dc7258ef2 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -397,30 +397,6 @@ static void context_close(struct i915_gem_context *ctx)
  	i915_gem_context_put(ctx);
  }
-static u32 default_desc_template(const struct drm_i915_private *i915,
-				 const struct i915_address_space *vm)
-{
-	u32 address_mode;
-	u32 desc;
-
-	desc = GEN8_CTX_VALID | GEN8_CTX_PRIVILEGE;
-
-	address_mode = INTEL_LEGACY_32B_CONTEXT;
-	if (vm && i915_vm_is_4lvl(vm))
-		address_mode = INTEL_LEGACY_64B_CONTEXT;
-	desc |= address_mode << GEN8_CTX_ADDRESSING_MODE_SHIFT;
-
-	if (IS_GEN(i915, 8))
-		desc |= GEN8_CTX_L3LLC_COHERENT;
-
-	/* TODO: WaDisableLiteRestore when we start using semaphore
-	 * signalling between Command Streamers
-	 * ring->ctx_desc_template |= GEN8_CTX_FORCE_RESTORE;
-	 */
-
-	return desc;
-}
-
  static struct i915_gem_context *
  __create_context(struct drm_i915_private *i915)
  {
@@ -459,7 +435,6 @@ __create_context(struct drm_i915_private *i915)
  	i915_gem_context_set_recoverable(ctx);
ctx->ring_size = 4 * PAGE_SIZE;
-	ctx->desc_template = default_desc_template(i915, NULL);
for (i = 0; i < ARRAY_SIZE(ctx->hang_timestamp); i++)
  		ctx->hang_timestamp[i] = jiffies - CONTEXT_FAST_HANG_JIFFIES;
@@ -478,8 +453,9 @@ __set_ppgtt(struct i915_gem_context *ctx, struct i915_address_space *vm)
  	struct i915_gem_engines_iter it;
  	struct intel_context *ce;
+ GEM_BUG_ON(old && i915_vm_is_4lvl(vm) != i915_vm_is_4lvl(old));
+
  	ctx->vm = i915_vm_get(vm);
-	ctx->desc_template = default_desc_template(ctx->i915, vm);
for_each_gem_engine(ce, i915_gem_context_lock_engines(ctx), it) {
  		i915_vm_put(ce->vm);
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
index 0ee61482ef94..a02d98494078 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
@@ -171,8 +171,6 @@ struct i915_gem_context {
/** ring_size: size for allocating the per-engine ring buffer */
  	u32 ring_size;
-	/** desc_template: invariant fields for the HW context descriptor */
-	u32 desc_template;
/** guilty_count: How many times this context has caused a GPU hang. */
  	atomic_t guilty_count;
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 632344c163a8..5fdac40015cf 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -418,13 +418,17 @@ lrc_descriptor(struct intel_context *ce, struct intel_engine_cs *engine)
  	BUILD_BUG_ON(MAX_CONTEXT_HW_ID > (BIT(GEN8_CTX_ID_WIDTH)));
  	BUILD_BUG_ON(GEN11_MAX_CONTEXT_HW_ID > (BIT(GEN11_SW_CTX_ID_WIDTH)));
- desc = ctx->desc_template; /* bits 0-11 */
-	GEM_BUG_ON(desc & GENMASK_ULL(63, 12));
+	desc = INTEL_LEGACY_32B_CONTEXT;
+	if (i915_vm_is_4lvl(ce->vm))
+		desc = INTEL_LEGACY_64B_CONTEXT;

if-else now that the vm null check is gone.

+	desc <<= GEN8_CTX_ADDRESSING_MODE_SHIFT;
+
+	desc |= GEN8_CTX_VALID | GEN8_CTX_PRIVILEGE;
+	if (IS_GEN(engine->i915, 8))
+		desc |= GEN8_CTX_L3LLC_COHERENT;

Don't know.. it's nicer to keep it stored it both for Gen and context state. What's the problem with it?

Regards,

Tvrtko

desc |= i915_ggtt_offset(ce->state) + LRC_HEADER_PAGES * PAGE_SIZE;
  								/* bits 12-31 */
-	GEM_BUG_ON(desc & GENMASK_ULL(63, 32));
-
  	/*
  	 * The following 32bits are copied into the OA reports (dword 2).
  	 * Consider updating oa_get_render_ctx_id in i915_perf.c when changing
diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c
index f68798ab1e7c..4c018fb1359c 100644
--- a/drivers/gpu/drm/i915/gvt/scheduler.c
+++ b/drivers/gpu/drm/i915/gvt/scheduler.c
@@ -291,9 +291,6 @@ shadow_context_descriptor_update(struct intel_context *ce,
  	 * Update bits 0-11 of the context descriptor which includes flags
  	 * like GEN8_CTX_* cached in desc_template
  	 */
-	desc &= U64_MAX << 12;
-	desc |= ce->gem_context->desc_template & ((1ULL << 12) - 1);
-
  	desc &= ~(0x3 << GEN8_CTX_ADDRESSING_MODE_SHIFT);
  	desc |= workload->ctx_desc.addressing_mode <<
  		GEN8_CTX_ADDRESSING_MODE_SHIFT;

_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx




[Index of Archives]     [AMD Graphics]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux