[Mesa-dev] [PATCH v4 1/2] i965/batch: avoid reverting batch buffer if saved state is an empty

[asimiklit.work at gmail.com]

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

There's no point reverting to the last saved point if that save point is
the empty batch, we will just repeat ourselves.

v2: Merge with new commits, changes was minimized, added the 'fixes' tag
v3: Added in to patch series
v4: Fixed the regression which was introduced by this patch
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108630
    Reported-by:  Mark Janes <mark.a.janes at intel.com>
    The solution provided by: Jordan Justen <jordan.l.justen at intel.com>

CC: Chris Wilson <chris at chris-wilson.co.uk>
Fixes: 3faf56ffbdeb "intel: Add an interface for saving/restoring
                     the batchbuffer state."
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107626
Signed-off-by: Andrii Simiklit <andrii.simiklit at globallogic.com>
---
 src/mesa/drivers/dri/i965/brw_compute.c       | 3 ++-
 src/mesa/drivers/dri/i965/brw_draw.c          | 3 ++-
 src/mesa/drivers/dri/i965/genX_blorp_exec.c   | 1 +
 src/mesa/drivers/dri/i965/intel_batchbuffer.c | 7 +++++++
 src/mesa/drivers/dri/i965/intel_batchbuffer.h | 1 +
 5 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_compute.c b/src/mesa/drivers/dri/i965/brw_compute.c
index de08fc3ac1..5c8e3a5d4d 100644
--- a/src/mesa/drivers/dri/i965/brw_compute.c
+++ b/src/mesa/drivers/dri/i965/brw_compute.c
@@ -167,7 +167,7 @@ static void
 brw_dispatch_compute_common(struct gl_context *ctx)
 {
    struct brw_context *brw = brw_context(ctx);
-   bool fail_next = false;
+   bool fail_next;
 
    if (!_mesa_check_conditional_render(ctx))
       return;
@@ -185,6 +185,7 @@ brw_dispatch_compute_common(struct gl_context *ctx)
    intel_batchbuffer_require_space(brw, 600);
    brw_require_statebuffer_space(brw, 2500);
    intel_batchbuffer_save_state(brw);
+   fail_next = intel_batchbuffer_saved_state_is_empty(brw);
 
  retry:
    brw->batch.no_wrap = true;
diff --git a/src/mesa/drivers/dri/i965/brw_draw.c b/src/mesa/drivers/dri/i965/brw_draw.c
index 8536c04010..19ee3962d7 100644
--- a/src/mesa/drivers/dri/i965/brw_draw.c
+++ b/src/mesa/drivers/dri/i965/brw_draw.c
@@ -885,7 +885,7 @@ brw_draw_single_prim(struct gl_context *ctx,
 {
    struct brw_context *brw = brw_context(ctx);
    const struct gen_device_info *devinfo = &brw->screen->devinfo;
-   bool fail_next = false;
+   bool fail_next;
 
    /* Flag BRW_NEW_DRAW_CALL on every draw.  This allows us to have
     * atoms that happen on every draw call.
@@ -898,6 +898,7 @@ brw_draw_single_prim(struct gl_context *ctx,
    intel_batchbuffer_require_space(brw, 1500);
    brw_require_statebuffer_space(brw, 2400);
    intel_batchbuffer_save_state(brw);
+   fail_next = intel_batchbuffer_saved_state_is_empty(brw);
 
    if (brw->num_instances != prim->num_instances ||
        brw->basevertex != prim->basevertex ||
diff --git a/src/mesa/drivers/dri/i965/genX_blorp_exec.c b/src/mesa/drivers/dri/i965/genX_blorp_exec.c
index 34bfcad03e..a62b88e166 100644
--- a/src/mesa/drivers/dri/i965/genX_blorp_exec.c
+++ b/src/mesa/drivers/dri/i965/genX_blorp_exec.c
@@ -309,6 +309,7 @@ retry:
    intel_batchbuffer_require_space(brw, 1400);
    brw_require_statebuffer_space(brw, 600);
    intel_batchbuffer_save_state(brw);
+   check_aperture_failed_once |= intel_batchbuffer_saved_state_is_empty(brw);
    brw->batch.no_wrap = true;
 
 #if GEN_GEN == 6
diff --git a/src/mesa/drivers/dri/i965/intel_batchbuffer.c b/src/mesa/drivers/dri/i965/intel_batchbuffer.c
index 8b769eaf53..6207de5a06 100644
--- a/src/mesa/drivers/dri/i965/intel_batchbuffer.c
+++ b/src/mesa/drivers/dri/i965/intel_batchbuffer.c
@@ -301,6 +301,13 @@ intel_batchbuffer_save_state(struct brw_context *brw)
    brw->batch.saved.exec_count = brw->batch.exec_count;
 }
 
+bool
+intel_batchbuffer_saved_state_is_empty(struct brw_context *brw)
+{
+   struct intel_batchbuffer *batch = &brw->batch;
+   return (batch->saved.map_next == batch->batch.map);
+}
+
 void
 intel_batchbuffer_reset_to_saved(struct brw_context *brw)
 {
diff --git a/src/mesa/drivers/dri/i965/intel_batchbuffer.h b/src/mesa/drivers/dri/i965/intel_batchbuffer.h
index 0632142cd3..91720dad5b 100644
--- a/src/mesa/drivers/dri/i965/intel_batchbuffer.h
+++ b/src/mesa/drivers/dri/i965/intel_batchbuffer.h
@@ -24,6 +24,7 @@ struct intel_batchbuffer;
 void intel_batchbuffer_init(struct brw_context *brw);
 void intel_batchbuffer_free(struct intel_batchbuffer *batch);
 void intel_batchbuffer_save_state(struct brw_context *brw);
+bool intel_batchbuffer_saved_state_is_empty(struct brw_context *brw);
 void intel_batchbuffer_reset_to_saved(struct brw_context *brw);
 void intel_batchbuffer_require_space(struct brw_context *brw, GLuint sz);
 int _intel_batchbuffer_flush_fence(struct brw_context *brw,
-- 
2.17.1