From 494593e6b2b989c2c17c52c989dde625d301a494 Mon Sep 17 00:00:00 2001 From: Kenneth Graunke Date: Thu, 14 Aug 2014 22:46:54 -0700 Subject: [PATCH] i965: Use the upload BO for push constants on Gen9+. Shaders can use quite a bit of uniform data. Better to put it in the upload buffers, like we do for client vertex data, rather than the batch buffer state area, which is primarly used for indirect state. This should free up batch space, allowing us to emit more commands in a batch before flushing. Because BRW_NEW_BATCH also causes a lot of state to be re-emitted, it may also reduce CPU overhead a little bit. We took this approach on Gen4-5, but switched to using the batch area on Gen6+ because buffer 0 is relative to Dynamic State Base Address by default, which is set to the start of the batch. On Gen9+, we already use a relocation due to a workaround, so this is trivial to change and has basically no downside. Unfortunately we can't change compute shader push constants because MEDIA_CURBE_LOAD always uses an offset from dynamic state base address. Improves performance in GLBenchmark 2.7/TRex Offscreen by: - Skylake GT4e: 0.52821% +/- 0.113402% (n = 190) - Apollolake: 0.510225% +/- 0.273064% (n = 70) Reviewed-by: Chris Forbes --- src/mesa/drivers/dri/i965/gen6_constant_state.c | 15 ++++++++++----- src/mesa/drivers/dri/i965/genX_state_upload.c | 2 +- 2 files changed, 11 insertions(+), 6 deletions(-) diff --git a/src/mesa/drivers/dri/i965/gen6_constant_state.c b/src/mesa/drivers/dri/i965/gen6_constant_state.c index 460f1c5..749e77e 100644 --- a/src/mesa/drivers/dri/i965/gen6_constant_state.c +++ b/src/mesa/drivers/dri/i965/gen6_constant_state.c @@ -25,6 +25,7 @@ #include "brw_state.h" #include "brw_defines.h" #include "intel_batchbuffer.h" +#include "intel_buffer_objects.h" #include "program/prog_parameter.h" /** @@ -60,12 +61,16 @@ gen6_upload_push_constants(struct brw_context *brw, if (prog) _mesa_load_state_parameters(ctx, prog->Parameters); - gl_constant_value *param; int i; - - param = brw_state_batch(brw, - prog_data->nr_params * sizeof(gl_constant_value), - 32, &stage_state->push_const_offset); + const int size = prog_data->nr_params * sizeof(gl_constant_value); + gl_constant_value *param; + if (brw->gen >= 9) { + param = intel_upload_space(brw, size, 32, &brw->curbe.curbe_bo, + &stage_state->push_const_offset); + } else { + param = brw_state_batch(brw, size, 32, + &stage_state->push_const_offset); + } STATIC_ASSERT(sizeof(gl_constant_value) == sizeof(float)); diff --git a/src/mesa/drivers/dri/i965/genX_state_upload.c b/src/mesa/drivers/dri/i965/genX_state_upload.c index 64ba357..f7128ae 100644 --- a/src/mesa/drivers/dri/i965/genX_state_upload.c +++ b/src/mesa/drivers/dri/i965/genX_state_upload.c @@ -2601,7 +2601,7 @@ upload_constant_state(struct brw_context *brw, pkt.ConstantBody.ConstantBuffer2ReadLength = stage_state->push_const_size; pkt.ConstantBody.PointerToConstantBuffer2 = - render_ro_bo(brw->batch.bo, stage_state->push_const_offset); + render_ro_bo(brw->curbe.curbe_bo, stage_state->push_const_offset); #else pkt.ConstantBody.ConstantBuffer0ReadLength = stage_state->push_const_size; -- 2.7.4