[Mesa-dev] [PATCH 1/2] i965: add missing rollback of URB requirements

[asimiklit.work at gmail.com]

From: Andrii Simiklit <andrii.simiklit at globallogic.com>

This patch is needed to avoid missing 3DSTATE_URB_* commands in a batch after
rollback operation.

To be able to test easily this issue
the following workaround is necessary:
-if (!brw_batch_has_aperture_space(brw, 0)) {
by:
+if (true) {
in brw_draw_single_prim function.

This workaround forces a rollback for each batch.
The "gl-3.2-adj-prims pv-first -auto -fbo" piglit test with this workaround
led to a hung. The hung investigation helped to find that some batches
didn't have the 3DSTATE_URB_* commands in compare to batches which were
generated without this workaround.

Reported-by: Kenneth Graunke <kenneth at whitecape.org>
Signed-off-by: Andrii Simiklit <andrii.simiklit at globallogic.com>
---
 src/mesa/drivers/dri/i965/brw_context.h       |  8 ++++++++
 src/mesa/drivers/dri/i965/intel_batchbuffer.c | 12 ++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
index 7fd15669eb..4e1682ba5c 100644
--- a/src/mesa/drivers/dri/i965/brw_context.h
+++ b/src/mesa/drivers/dri/i965/brw_context.h
@@ -521,6 +521,14 @@ struct intel_batchbuffer {
       int batch_reloc_count;
       int state_reloc_count;
       int exec_count;
+      struct {
+         GLuint vsize;
+         GLuint gsize;
+         GLuint hsize;
+         GLuint dsize;
+         bool gs_present;
+         bool tess_present;
+      } urb;
    } saved;
 
    /** Map from batch offset to brw_state_batch data (with DEBUG_BATCH) */
diff --git a/src/mesa/drivers/dri/i965/intel_batchbuffer.c b/src/mesa/drivers/dri/i965/intel_batchbuffer.c
index 353fcba18f..bae9f2ffed 100644
--- a/src/mesa/drivers/dri/i965/intel_batchbuffer.c
+++ b/src/mesa/drivers/dri/i965/intel_batchbuffer.c
@@ -299,6 +299,12 @@ intel_batchbuffer_save_state(struct brw_context *brw)
    brw->batch.saved.batch_reloc_count = brw->batch.batch_relocs.reloc_count;
    brw->batch.saved.state_reloc_count = brw->batch.state_relocs.reloc_count;
    brw->batch.saved.exec_count = brw->batch.exec_count;
+   brw->batch.saved.urb.vsize = brw->urb.vsize;
+   brw->batch.saved.urb.gs_present = brw->urb.gs_present;
+   brw->batch.saved.urb.gsize = brw->urb.gsize;
+   brw->batch.saved.urb.tess_present = brw->urb.tess_present;
+   brw->batch.saved.urb.hsize = brw->urb.hsize;
+   brw->batch.saved.urb.dsize = brw->urb.dsize;
 }
 
 void
@@ -313,6 +319,12 @@ intel_batchbuffer_reset_to_saved(struct brw_context *brw)
    brw->batch.exec_count = brw->batch.saved.exec_count;
 
    brw->batch.map_next = brw->batch.saved.map_next;
+   brw->urb.vsize = brw->batch.saved.urb.vsize;
+   brw->urb.gs_present = brw->batch.saved.urb.gs_present;
+   brw->urb.gsize = brw->batch.saved.urb.gsize;
+   brw->urb.tess_present = brw->batch.saved.urb.tess_present;
+   brw->urb.hsize = brw->batch.saved.urb.hsize;
+   brw->urb.dsize = brw->batch.saved.urb.dsize;
    if (USED_BATCH(brw->batch) == 0)
       brw_new_batch(brw);
 }
-- 
2.17.1