From: Kenneth Graunke <kenneth@whitecape.org>
Date: Fri, 8 Sep 2017 22:00:14 +0000 (-0700)
Subject: i965: Use a WC map and memcpy for the batch instead of pwrite.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=717e7539124dc459276385a02847b06ea1989973;p=mesa.git

i965: Use a WC map and memcpy for the batch instead of pwrite.

We'd like to eliminate the malloc'd shadow copy eventually, but there
are still unresolved performance problems.  In the meantime, let's at
least get rid of pwrite.

On Apollolake, improves Synmark OglBatch6 performance by:
1.53581% +/- 0.269589% (n=108).

Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
---

diff --git a/src/mesa/drivers/dri/i965/intel_batchbuffer.c b/src/mesa/drivers/dri/i965/intel_batchbuffer.c
index 276fe458a13..9cd491b5ace 100644
--- a/src/mesa/drivers/dri/i965/intel_batchbuffer.c
+++ b/src/mesa/drivers/dri/i965/intel_batchbuffer.c
@@ -629,18 +629,16 @@ do_flush_locked(struct brw_context *brw, int in_fence_fd, int *out_fence_fd)
    struct intel_batchbuffer *batch = &brw->batch;
    int ret = 0;
 
-   if (devinfo->has_llc) {
-      brw_bo_unmap(batch->bo);
-   } else {
-      ret = brw_bo_subdata(batch->bo, 0, 4 * USED_BATCH(*batch), batch->map);
-      if (ret == 0 && batch->state_batch_offset != batch->bo->size) {
-         ret = brw_bo_subdata(batch->bo,
-                              batch->state_batch_offset,
-                              batch->bo->size - batch->state_batch_offset,
-                              (char *)batch->map + batch->state_batch_offset);
-      }
+   if (batch->cpu_map) {
+      void *bo_map = brw_bo_map(brw, batch->bo, MAP_WRITE);
+      memcpy(bo_map, batch->cpu_map, 4 * USED_BATCH(*batch));
+      memcpy(bo_map + batch->state_batch_offset,
+             (char *) batch->cpu_map + batch->state_batch_offset,
+             batch->bo->size - batch->state_batch_offset);
    }
 
+   brw_bo_unmap(batch->bo);
+
    if (!brw->screen->no_hw) {
       /* The requirement for using I915_EXEC_NO_RELOC are:
        *