From e1a73a54a96e80dc6009e73c9209e4f81ae22285 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 25 Jan 2019 10:05:20 +0000 Subject: [PATCH] drm/i915: Measure the required reserved size for request emission Instead of tediously and fragilely counting up the number of dwords required to emit the breadcrumb to seal a request, fake a request and measure it automatically once during engine setup. The downside is that this requires a fair amount of mocking to create a proper breadcrumb. Still, should be less error prone in future as the breadcrumb size fluctuates! Signed-off-by: Chris Wilson Reviewed-by: Mika Kuoppala Link: https://patchwork.freedesktop.org/patch/msgid/20190125100520.20163-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/intel_engine_cs.c | 49 ++++++++++++++++++++ drivers/gpu/drm/i915/intel_lrc.c | 12 +++-- drivers/gpu/drm/i915/intel_ringbuffer.c | 24 +++++++--- drivers/gpu/drm/i915/intel_ringbuffer.h | 2 +- drivers/gpu/drm/i915/selftests/mock_engine.c | 4 +- 5 files changed, 77 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c index 2f3c71f6d313..8f738a7cd117 100644 --- a/drivers/gpu/drm/i915/intel_engine_cs.c +++ b/drivers/gpu/drm/i915/intel_engine_cs.c @@ -604,6 +604,47 @@ static void __intel_context_unpin(struct i915_gem_context *ctx, intel_context_unpin(to_intel_context(ctx, engine)); } +struct measure_breadcrumb { + struct i915_request rq; + struct i915_timeline timeline; + struct intel_ring ring; + u32 cs[1024]; +}; + +static int measure_breadcrumb_sz(struct intel_engine_cs *engine) +{ + struct measure_breadcrumb *frame; + unsigned int dw; + + GEM_BUG_ON(!engine->i915->gt.scratch); + + frame = kzalloc(sizeof(*frame), GFP_KERNEL); + if (!frame) + return -ENOMEM; + + i915_timeline_init(engine->i915, &frame->timeline, "measure"); + + INIT_LIST_HEAD(&frame->ring.request_list); + frame->ring.timeline = &frame->timeline; + frame->ring.vaddr = frame->cs; + frame->ring.size = sizeof(frame->cs); + frame->ring.effective_size = frame->ring.size; + intel_ring_update_space(&frame->ring); + + frame->rq.i915 = engine->i915; + frame->rq.engine = engine; + frame->rq.ring = &frame->ring; + frame->rq.timeline = &frame->timeline; + + dw = engine->emit_breadcrumb(&frame->rq, frame->cs) - frame->cs; + GEM_BUG_ON(dw != engine->emit_breadcrumb_sz); + + i915_timeline_fini(&frame->timeline); + kfree(frame); + + return dw; +} + /** * intel_engines_init_common - initialize cengine state which might require hw access * @engine: Engine to initialize. @@ -657,8 +698,16 @@ int intel_engine_init_common(struct intel_engine_cs *engine) if (ret) goto err_breadcrumbs; + ret = measure_breadcrumb_sz(engine); + if (ret < 0) + goto err_status_page; + + engine->emit_breadcrumb_sz = ret; + return 0; +err_status_page: + cleanup_status_page(engine); err_breadcrumbs: intel_engine_fini_breadcrumbs(engine); err_unpin_preempt: diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 9155cc675924..d2299425cf2f 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -2051,15 +2051,17 @@ static int gen8_emit_flush_render(struct i915_request *request, * used as a workaround for not being allowed to do lite * restore with HEAD==TAIL (WaIdleLiteRestore). */ -static void gen8_emit_wa_tail(struct i915_request *request, u32 *cs) +static u32 *gen8_emit_wa_tail(struct i915_request *request, u32 *cs) { /* Ensure there's always at least one preemption point per-request. */ *cs++ = MI_ARB_CHECK; *cs++ = MI_NOOP; request->wa_tail = intel_ring_offset(request, cs); + + return cs; } -static void gen8_emit_breadcrumb(struct i915_request *request, u32 *cs) +static u32 *gen8_emit_breadcrumb(struct i915_request *request, u32 *cs) { /* w/a: bit 5 needs to be zero for MI_FLUSH_DW address. */ BUILD_BUG_ON(I915_GEM_HWS_INDEX_ADDR & (1 << 5)); @@ -2071,11 +2073,11 @@ static void gen8_emit_breadcrumb(struct i915_request *request, u32 *cs) request->tail = intel_ring_offset(request, cs); assert_ring_tail_valid(request->ring, request->tail); - gen8_emit_wa_tail(request, cs); + return gen8_emit_wa_tail(request, cs); } static const int gen8_emit_breadcrumb_sz = 6 + WA_TAIL_DWORDS; -static void gen8_emit_breadcrumb_rcs(struct i915_request *request, u32 *cs) +static u32 *gen8_emit_breadcrumb_rcs(struct i915_request *request, u32 *cs) { /* We're using qword write, seqno should be aligned to 8 bytes. */ BUILD_BUG_ON(I915_GEM_HWS_INDEX & 1); @@ -2095,7 +2097,7 @@ static void gen8_emit_breadcrumb_rcs(struct i915_request *request, u32 *cs) request->tail = intel_ring_offset(request, cs); assert_ring_tail_valid(request->ring, request->tail); - gen8_emit_wa_tail(request, cs); + return gen8_emit_wa_tail(request, cs); } static const int gen8_emit_breadcrumb_rcs_sz = 8 + WA_TAIL_DWORDS; diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index e39e483d8d16..107c4934e2fa 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -299,7 +299,7 @@ gen6_render_ring_flush(struct i915_request *rq, u32 mode) return 0; } -static void gen6_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) +static u32 *gen6_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) { /* First we do the gen6_emit_post_sync_nonzero_flush w/a */ *cs++ = GFX_OP_PIPE_CONTROL(4); @@ -327,6 +327,8 @@ static void gen6_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) rq->tail = intel_ring_offset(rq, cs); assert_ring_tail_valid(rq->ring, rq->tail); + + return cs; } static const int gen6_rcs_emit_breadcrumb_sz = 14; @@ -409,7 +411,7 @@ gen7_render_ring_flush(struct i915_request *rq, u32 mode) return 0; } -static void gen7_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) +static u32 *gen7_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) { *cs++ = GFX_OP_PIPE_CONTROL(4); *cs++ = (PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH | @@ -427,10 +429,12 @@ static void gen7_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) rq->tail = intel_ring_offset(rq, cs); assert_ring_tail_valid(rq->ring, rq->tail); + + return cs; } static const int gen7_rcs_emit_breadcrumb_sz = 6; -static void gen6_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) +static u32 *gen6_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) { *cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW; *cs++ = intel_hws_seqno_address(rq->engine) | MI_FLUSH_DW_USE_GTT; @@ -439,11 +443,13 @@ static void gen6_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) rq->tail = intel_ring_offset(rq, cs); assert_ring_tail_valid(rq->ring, rq->tail); + + return cs; } static const int gen6_xcs_emit_breadcrumb_sz = 4; #define GEN7_XCS_WA 32 -static void gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) +static u32 *gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) { int i; @@ -466,6 +472,8 @@ static void gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs) rq->tail = intel_ring_offset(rq, cs); assert_ring_tail_valid(rq->ring, rq->tail); + + return cs; } static const int gen7_xcs_emit_breadcrumb_sz = 8 + GEN7_XCS_WA * 3; #undef GEN7_XCS_WA @@ -861,7 +869,7 @@ static void i9xx_submit_request(struct i915_request *request) intel_ring_set_tail(request->ring, request->tail)); } -static void i9xx_emit_breadcrumb(struct i915_request *rq, u32 *cs) +static u32 *i9xx_emit_breadcrumb(struct i915_request *rq, u32 *cs) { *cs++ = MI_FLUSH; @@ -874,11 +882,13 @@ static void i9xx_emit_breadcrumb(struct i915_request *rq, u32 *cs) rq->tail = intel_ring_offset(rq, cs); assert_ring_tail_valid(rq->ring, rq->tail); + + return cs; } static const int i9xx_emit_breadcrumb_sz = 6; #define GEN5_WA_STORES 8 /* must be at least 1! */ -static void gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs) +static u32 *gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs) { int i; @@ -895,6 +905,8 @@ static void gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs) rq->tail = intel_ring_offset(rq, cs); assert_ring_tail_valid(rq->ring, rq->tail); + + return cs; } static const int gen5_emit_breadcrumb_sz = GEN5_WA_STORES * 3 + 2; #undef GEN5_WA_STORES diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h index c3ef0f9bf321..479bd53d4ac6 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.h +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h @@ -470,7 +470,7 @@ struct intel_engine_cs { unsigned int dispatch_flags); #define I915_DISPATCH_SECURE BIT(0) #define I915_DISPATCH_PINNED BIT(1) - void (*emit_breadcrumb)(struct i915_request *rq, u32 *cs); + u32 *(*emit_breadcrumb)(struct i915_request *rq, u32 *cs); int emit_breadcrumb_sz; /* Pass the request to the hardware queue (e.g. directly into diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c index 442ec2aeec81..905318b7ae18 100644 --- a/drivers/gpu/drm/i915/selftests/mock_engine.c +++ b/drivers/gpu/drm/i915/selftests/mock_engine.c @@ -159,9 +159,9 @@ static int mock_emit_flush(struct i915_request *request, return 0; } -static void mock_emit_breadcrumb(struct i915_request *request, - u32 *flags) +static u32 *mock_emit_breadcrumb(struct i915_request *request, u32 *cs) { + return cs; } static void mock_submit_request(struct i915_request *request)