svga: cache the backing surface handle in the texture object

CinebenchR15 not only binds the same texture for rendering and sampling,
it actually changes the framebuffer buffer attachment very often, causing
a lot of backed surface view to be created and a lot of surface copies
to be done. This patch caches the backed surface handle
in the texture resource and allows the backed surface view to
reuse the backed surface handle.  With this patch, the number of
backed surface view reduces from 1312 to 3. Unfortunately, this
does not eliminate all the surface copies. There are still surface
copies involved when we switch from original to backed surface handle
for rendering.

Tested with CinebenchR15, NobelClinicianViewer, Turbine, Lightsmark2008,
            MTT glretrace, MTT piglit.

Reviewed-by: Brian Paul <brianp@vmware.com>

5 files changed, 57 insertions, 10 deletions

diff --git a/src/gallium/drivers/svga/svga_resource_texture.c b/src/gallium/drivers/svga/svga_resource_texture.c
index 20580e9dd922..1e2dfa82728b 100644
--- a/src/gallium/drivers/svga/svga_resource_texture.c
+++ b/src/gallium/drivers/svga/svga_resource_texture.c
@@ -238,6 +238,10 @@ svga_texture_destroy(struct pipe_screen *screen,
    SVGA_DBG(DEBUG_DMA, "unref sid %p (texture)\n", tex->handle);
    svga_screen_surface_destroy(ss, &tex->key, &tex->handle);
 
+   /* Destroy the backed surface handle if exists */
+   if (tex->backed_handle)
+      svga_screen_surface_destroy(ss, &tex->backed_key, &tex->backed_handle);
+      
    ss->hud.total_resource_bytes -= tex->size;
 
    FREE(tex->defined);
@@ -1119,6 +1123,9 @@ svga_texture_create(struct pipe_screen *screen,
    tex->can_use_upload = svga_texture_transfer_map_can_upload(svgascreen,
                                                               &tex->b.b);
 
+   /* Initialize the backing resource cache */
+   tex->backed_handle = NULL;
+
    svgascreen->hud.total_resource_bytes += tex->size;
    svgascreen->hud.num_resources++;
 
diff --git a/src/gallium/drivers/svga/svga_resource_texture.h b/src/gallium/drivers/svga/svga_resource_texture.h
index 9f7b0c6e6596..4cb98970a5bc 100644
--- a/src/gallium/drivers/svga/svga_resource_texture.h
+++ b/src/gallium/drivers/svga/svga_resource_texture.h
@@ -104,6 +104,16 @@ struct svga_texture
     *  Set if the level is marked as dirty.
     */ 
    ushort *dirty;
+
+   /**
+    * A cached backing host side surface to be used if this texture is being
+    * used for rendering and sampling at the same time.
+    * Currently we only cache one handle. If needed, we can extend this to
+    * support multiple handles.
+    */
+   struct svga_host_surface_cache_key backed_key;
+   struct svga_winsys_surface *backed_handle;
+   unsigned backed_age;
 };
 
 
diff --git a/src/gallium/drivers/svga/svga_sampler_view.c b/src/gallium/drivers/svga/svga_sampler_view.c
index ee4ef3ca7b07..80a1b926a997 100644
--- a/src/gallium/drivers/svga/svga_sampler_view.c
+++ b/src/gallium/drivers/svga/svga_sampler_view.c
@@ -151,7 +151,7 @@ svga_get_tex_sampler_view(struct pipe_context *pipe,
                                           flags, format,
                                           min_lod,
                                           max_lod - min_lod + 1,
-                                          -1, 1, -1,
+                                          -1, 1, -1, FALSE,
                                           &sv->key);
 
    if (!sv->handle) {
diff --git a/src/gallium/drivers/svga/svga_surface.c b/src/gallium/drivers/svga/svga_surface.c
index cbeaa2390cd8..795a7b8ffd60 100644
--- a/src/gallium/drivers/svga/svga_surface.c
+++ b/src/gallium/drivers/svga/svga_surface.c
@@ -158,11 +158,13 @@ svga_texture_view_surface(struct svga_context *svga,
                           int layer_pick,
                           unsigned num_layers,
                           int zslice_pick,
+                          boolean cacheable,
                           struct svga_host_surface_cache_key *key) /* OUT */
 {
    struct svga_screen *ss = svga_screen(svga->pipe.screen);
    struct svga_winsys_surface *handle;
    boolean validated;
+   boolean needCopyResource;
 
    SVGA_DBG(DEBUG_PERF,
             "svga: Create surface view: layer %d zslice %d mips %d..%d\n",
@@ -198,9 +200,22 @@ svga_texture_view_surface(struct svga_context *svga,
       return NULL;
    }
 
-   SVGA_DBG(DEBUG_DMA, "surface_create for texture view\n");
-   handle = svga_screen_surface_create(ss, bind_flags, PIPE_USAGE_DEFAULT,
-                                       &validated, key);
+   if (cacheable && tex->backed_handle &&
+       memcmp(key, &tex->backed_key, sizeof *key) == 0) {
+      handle = tex->backed_handle;
+      needCopyResource = tex->backed_age < tex->age;
+   } else {
+      SVGA_DBG(DEBUG_DMA, "surface_create for texture view\n");
+      handle = svga_screen_surface_create(ss, bind_flags, PIPE_USAGE_DEFAULT,
+                                          &validated, key);
+      needCopyResource = TRUE;
+
+      if (cacheable && !tex->backed_handle) {
+         tex->backed_handle = handle;
+         memcpy(&tex->backed_key, key, sizeof *key);
+      }
+   }
+
    if (!handle) {
       key->cachable = 0;
       return NULL;
@@ -211,10 +226,13 @@ svga_texture_view_surface(struct svga_context *svga,
    if (layer_pick < 0)
       layer_pick = 0;
 
-   svga_texture_copy_handle_resource(svga, tex, handle,
-                                     key->numMipLevels,
-                                     key->numFaces * key->arraySize,
-                                     zslice_pick, start_mip, layer_pick);
+   if (needCopyResource) {
+      svga_texture_copy_handle_resource(svga, tex, handle,
+                                        key->numMipLevels,
+                                        key->numFaces * key->arraySize,
+                                        zslice_pick, start_mip, layer_pick);
+      tex->backed_age = tex->age;
+   }
 
    return handle;
 }
@@ -328,7 +346,8 @@ svga_create_surface_view(struct pipe_context *pipe,
       s->handle = svga_texture_view_surface(svga, tex, bind, flags,
                                             tex->key.format,
                                             surf_tmpl->u.tex.level, 1,
-                                            layer, nlayers, zslice, &s->key);
+                                            layer, nlayers, zslice,
+                                            TRUE, &s->key);
       if (!s->handle) {
          FREE(s);
          goto done;
@@ -585,7 +604,10 @@ svga_surface_destroy(struct pipe_context *pipe,
       s->backed = NULL;
    }
 
-   if (s->handle != t->handle) {
+   /* Destroy the surface handle if this is a backed handle and
+    * it is not being cached in the texture.
+    */
+   if (s->handle != t->handle && s->handle != t->backed_handle) {
       SVGA_DBG(DEBUG_DMA, "unref sid %p (tex surface)\n", s->handle);
       svga_screen_surface_destroy(ss, &s->key, &s->handle);
    }
@@ -750,6 +772,13 @@ svga_propagate_surface(struct svga_context *svga, struct pipe_surface *surf,
 
       /* Sync the surface view age with the texture age */
       s->age = tex->age;
+
+      /* If this backed surface is cached in the texture,
+       * update the backed age as well.
+       */
+      if (tex->backed_handle == s->handle) {
+         tex->backed_age = tex->age;
+      }
    }
 
    SVGA_STATS_TIME_POP(ss->sws);
diff --git a/src/gallium/drivers/svga/svga_surface.h b/src/gallium/drivers/svga/svga_surface.h
index d1628d54525b..8df1006d2764 100644
--- a/src/gallium/drivers/svga/svga_surface.h
+++ b/src/gallium/drivers/svga/svga_surface.h
@@ -102,6 +102,7 @@ svga_texture_view_surface(struct svga_context *svga,
                           int layer_pick,
                           unsigned num_layers,
                           int zslice_pick,
+                          boolean cacheable,
                           struct svga_host_surface_cache_key *key); /* OUT */