glamor: Remove the FBO cache.

It is a modest performance improvement (2.7% on Intel), with the
significant downside that it keeps extra pixmap contents laying around
for 1000 BlockHandlers without the ability for the system to purge
them when under memory pressure, and tiled renderers don't know that
we could avoid reading their current contents when beginning to render
again.  We could use the FB invalidate functions, but they aren't
always available, aren't hooked up well in Mesa, and would eat into
the performance gains of having the cache.

[ajax: rebased to master]

Reviewed-by: Adam Jackson <ajax@redhat.com>

3 files changed, 6 insertions, 275 deletions

diff --git a/glamor/glamor.c b/glamor/glamor.c
index 7d82ce806..867c53dd6 100644
--- a/glamor/glamor.c
+++ b/glamor/glamor.c
@@ -110,7 +110,6 @@ glamor_set_pixmap_texture(PixmapPtr pixmap, unsigned int tex)
         ErrorF("XXX fail to create fbo.\n");
         return;
     }
-    fbo->external = TRUE;
 
     glamor_pixmap_attach_fbo(pixmap, fbo);
 }
@@ -254,9 +253,7 @@ glamor_block_handler(ScreenPtr screen)
     glamor_screen_private *glamor_priv = glamor_get_screen_private(screen);
 
     glamor_make_current(glamor_priv);
-    glamor_priv->tick++;
     glFlush();
-    glamor_fbo_expire(glamor_priv);
 }
 
 static void
@@ -709,7 +706,6 @@ glamor_init(ScreenPtr screen, unsigned int flags)
     ps->Glyphs = glamor_composite_glyphs;
 
     glamor_init_vbo(screen);
-    glamor_init_pixmap_fbo(screen);
 
 #ifdef GLAMOR_GRADIENT_SHADER
     glamor_init_gradient_shader(screen);
@@ -734,7 +730,6 @@ glamor_release_screen_priv(ScreenPtr screen)
 
     glamor_priv = glamor_get_screen_private(screen);
     glamor_fini_vbo(screen);
-    glamor_fini_pixmap_fbo(screen);
     glamor_pixmap_fini(screen);
     free(glamor_priv);
 
diff --git a/glamor/glamor_fbo.c b/glamor/glamor_fbo.c
index a531f6052..988bb585b 100644
--- a/glamor/glamor_fbo.c
+++ b/glamor/glamor_fbo.c
@@ -30,107 +30,9 @@
 
 #include "glamor_priv.h"
 
-#define GLAMOR_CACHE_EXPIRE_MAX 100
-
-#define GLAMOR_CACHE_DEFAULT    0
-#define GLAMOR_CACHE_EXACT_SIZE 1
-
-//#define NO_FBO_CACHE 1
-#define FBO_CACHE_THRESHOLD  (256*1024*1024)
-
-/* Loop from the tail to the head. */
-#define xorg_list_for_each_entry_reverse(pos, head, member)             \
-    for (pos = __container_of((head)->prev, pos, member);               \
-         &pos->member != (head);                                        \
-         pos = __container_of(pos->member.prev, pos, member))
-
-#define xorg_list_for_each_entry_safe_reverse(pos, tmp, head, member)   \
-    for (pos = __container_of((head)->prev, pos, member),               \
-         tmp = __container_of(pos->member.prev, pos, member);           \
-         &pos->member != (head);                                        \
-         pos = tmp, tmp = __container_of(pos->member.prev, tmp, member))
-
-inline static int
-cache_wbucket(int size)
-{
-    int order = __fls(size / 32);
-
-    if (order >= CACHE_BUCKET_WCOUNT)
-        order = CACHE_BUCKET_WCOUNT - 1;
-    return order;
-}
-
-inline static int
-cache_hbucket(int size)
-{
-    int order = __fls(size / 32);
-
-    if (order >= CACHE_BUCKET_HCOUNT)
-        order = CACHE_BUCKET_HCOUNT - 1;
-    return order;
-}
-
-static int
-cache_format(GLenum format)
-{
-    switch (format) {
-    case GL_ALPHA:
-    case GL_LUMINANCE:
-    case GL_RED:
-        return 2;
-    case GL_RGB:
-        return 1;
-    case GL_RGBA:
-        return 0;
-    default:
-        return -1;
-    }
-}
-
-static glamor_pixmap_fbo *
-glamor_pixmap_fbo_cache_get(glamor_screen_private *glamor_priv,
-                            int w, int h, GLenum format)
-{
-    struct xorg_list *cache;
-    glamor_pixmap_fbo *fbo_entry, *ret_fbo = NULL;
-    int n_format;
-
-#ifdef NO_FBO_CACHE
-    return NULL;
-#else
-    n_format = cache_format(format);
-    if (n_format == -1)
-        return NULL;
-    cache = &glamor_priv->fbo_cache[n_format]
-        [cache_wbucket(w)]
-        [cache_hbucket(h)];
-
-    xorg_list_for_each_entry(fbo_entry, cache, list) {
-        if (fbo_entry->width == w && fbo_entry->height == h) {
-
-            DEBUGF("Request w %d h %d format %x \n", w, h, format);
-            DEBUGF("got cache entry %p w %d h %d fbo %d tex %d format %x\n",
-                   fbo_entry, fbo_entry->width, fbo_entry->height,
-                   fbo_entry->fb, fbo_entry->tex, fbo_entry->format);
-            assert(format == fbo_entry->format);
-            xorg_list_del(&fbo_entry->list);
-            ret_fbo = fbo_entry;
-            break;
-        }
-    }
-
-    if (ret_fbo)
-        glamor_priv->fbo_cache_watermark -= ret_fbo->width * ret_fbo->height;
-
-    assert(glamor_priv->fbo_cache_watermark >= 0);
-
-    return ret_fbo;
-#endif
-}
-
-static void
-glamor_purge_fbo(glamor_screen_private *glamor_priv,
-                 glamor_pixmap_fbo *fbo)
+void
+glamor_destroy_fbo(glamor_screen_private *glamor_priv,
+                   glamor_pixmap_fbo *fbo)
 {
     glamor_make_current(glamor_priv);
 
@@ -142,52 +44,6 @@ glamor_purge_fbo(glamor_screen_private *glamor_priv,
     free(fbo);
 }
 
-static void
-glamor_pixmap_fbo_cache_put(glamor_screen_private *glamor_priv,
-                            glamor_pixmap_fbo *fbo)
-{
-    struct xorg_list *cache;
-    int n_format;
-
-#ifdef NO_FBO_CACHE
-    glamor_purge_fbo(fbo);
-    return;
-#else
-    n_format = cache_format(fbo->format);
-
-    if (fbo->fb == 0 || fbo->external || n_format == -1
-        || glamor_priv->fbo_cache_watermark >= FBO_CACHE_THRESHOLD) {
-        glamor_priv->tick += GLAMOR_CACHE_EXPIRE_MAX;
-        glamor_fbo_expire(glamor_priv);
-        glamor_purge_fbo(glamor_priv, fbo);
-        return;
-    }
-
-    cache = &glamor_priv->fbo_cache[n_format]
-        [cache_wbucket(fbo->width)]
-        [cache_hbucket(fbo->height)];
-    DEBUGF
-        ("Put cache entry %p to cache %p w %d h %d format %x fbo %d tex %d \n",
-         fbo, cache, fbo->width, fbo->height, fbo->format, fbo->fb, fbo->tex);
-
-    /* Reset the texture swizzle that may have been set by
-     * glamor_picture.c.  Don't reset GL_RED -> GL_ALPHA swizzle, though
-     */
-    if (glamor_priv->has_texture_swizzle && n_format != 2) {
-        glamor_make_current(glamor_priv);
-        glBindTexture(GL_TEXTURE_2D, fbo->tex);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_R, GL_RED);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_G, GL_GREEN);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_B, GL_BLUE);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_A, GL_ALPHA);
-    }
-
-    glamor_priv->fbo_cache_watermark += fbo->width * fbo->height;
-    xorg_list_add(&fbo->list, cache);
-    fbo->expire = glamor_priv->tick + GLAMOR_CACHE_EXPIRE_MAX;
-#endif
-}
-
 static int
 glamor_pixmap_ensure_fb(glamor_screen_private *glamor_priv,
                         glamor_pixmap_fbo *fbo)
@@ -247,20 +103,14 @@ glamor_create_fbo_from_tex(glamor_screen_private *glamor_priv,
     if (fbo == NULL)
         return NULL;
 
-    xorg_list_init(&fbo->list);
-
     fbo->tex = tex;
     fbo->width = w;
     fbo->height = h;
-    fbo->external = FALSE;
     fbo->format = format;
 
-    if (flag == CREATE_PIXMAP_USAGE_SHARED)
-        fbo->external = TRUE;
-
     if (flag != GLAMOR_CREATE_FBO_NO_FBO) {
         if (glamor_pixmap_ensure_fb(glamor_priv, fbo) != 0) {
-            glamor_purge_fbo(glamor_priv, fbo);
+            glamor_destroy_fbo(glamor_priv, fbo);
             fbo = NULL;
         }
     }
@@ -268,79 +118,6 @@ glamor_create_fbo_from_tex(glamor_screen_private *glamor_priv,
     return fbo;
 }
 
-void
-glamor_fbo_expire(glamor_screen_private *glamor_priv)
-{
-    struct xorg_list *cache;
-    glamor_pixmap_fbo *fbo_entry, *tmp;
-    int i, j, k;
-
-    for (i = 0; i < CACHE_FORMAT_COUNT; i++)
-        for (j = 0; j < CACHE_BUCKET_WCOUNT; j++)
-            for (k = 0; k < CACHE_BUCKET_HCOUNT; k++) {
-                cache = &glamor_priv->fbo_cache[i][j][k];
-                xorg_list_for_each_entry_safe_reverse(fbo_entry, tmp, cache,
-                                                      list) {
-                    if (GLAMOR_TICK_AFTER(fbo_entry->expire, glamor_priv->tick)) {
-                        break;
-                    }
-
-                    glamor_priv->fbo_cache_watermark -=
-                        fbo_entry->width * fbo_entry->height;
-                    xorg_list_del(&fbo_entry->list);
-                    DEBUGF("cache %p fbo %p expired %d current %d \n", cache,
-                           fbo_entry, fbo_entry->expire, glamor_priv->tick);
-                    glamor_purge_fbo(glamor_priv, fbo_entry);
-                }
-            }
-
-}
-
-void
-glamor_init_pixmap_fbo(ScreenPtr screen)
-{
-    glamor_screen_private *glamor_priv;
-    int i, j, k;
-
-    glamor_priv = glamor_get_screen_private(screen);
-    for (i = 0; i < CACHE_FORMAT_COUNT; i++)
-        for (j = 0; j < CACHE_BUCKET_WCOUNT; j++)
-            for (k = 0; k < CACHE_BUCKET_HCOUNT; k++) {
-                xorg_list_init(&glamor_priv->fbo_cache[i][j][k]);
-            }
-    glamor_priv->fbo_cache_watermark = 0;
-}
-
-void
-glamor_fini_pixmap_fbo(ScreenPtr screen)
-{
-    struct xorg_list *cache;
-    glamor_screen_private *glamor_priv;
-    glamor_pixmap_fbo *fbo_entry, *tmp;
-    int i, j, k;
-
-    glamor_priv = glamor_get_screen_private(screen);
-    for (i = 0; i < CACHE_FORMAT_COUNT; i++)
-        for (j = 0; j < CACHE_BUCKET_WCOUNT; j++)
-            for (k = 0; k < CACHE_BUCKET_HCOUNT; k++) {
-                cache = &glamor_priv->fbo_cache[i][j][k];
-                xorg_list_for_each_entry_safe_reverse(fbo_entry, tmp, cache,
-                                                      list) {
-                    xorg_list_del(&fbo_entry->list);
-                    glamor_purge_fbo(glamor_priv, fbo_entry);
-                }
-            }
-}
-
-void
-glamor_destroy_fbo(glamor_screen_private *glamor_priv,
-                   glamor_pixmap_fbo *fbo)
-{
-    xorg_list_del(&fbo->list);
-    glamor_pixmap_fbo_cache_put(glamor_priv, fbo);
-
-}
-
 static int
 _glamor_create_tex(glamor_screen_private *glamor_priv,
                    int w, int h, GLenum format)
@@ -378,22 +155,8 @@ glamor_pixmap_fbo *
 glamor_create_fbo(glamor_screen_private *glamor_priv,
                   int w, int h, GLenum format, int flag)
 {
-    glamor_pixmap_fbo *fbo;
-    GLint tex = 0;
-
-    if (flag == GLAMOR_CREATE_FBO_NO_FBO || flag == CREATE_PIXMAP_USAGE_SHARED)
-        goto new_fbo;
-
-    fbo = glamor_pixmap_fbo_cache_get(glamor_priv, w, h, format);
-    if (fbo)
-        return fbo;
- new_fbo:
-    tex = _glamor_create_tex(glamor_priv, w, h, format);
-    if (!tex)
-        return NULL;
-    fbo = glamor_create_fbo_from_tex(glamor_priv, w, h, format, tex, flag);
-
-    return fbo;
+    GLint tex = _glamor_create_tex(glamor_priv, w, h, format);
+    return glamor_create_fbo_from_tex(glamor_priv, w, h, format, tex, flag);
 }
 
 /**
diff --git a/glamor/glamor_priv.h b/glamor/glamor_priv.h
index c34eb84c0..2e491a689 100644
--- a/glamor/glamor_priv.h
+++ b/glamor/glamor_priv.h
@@ -184,16 +184,7 @@ struct glamor_saved_procs {
     ScreenBlockHandlerProcPtr block_handler;
 };
 
-#define CACHE_FORMAT_COUNT 3
-
-#define CACHE_BUCKET_WCOUNT 4
-#define CACHE_BUCKET_HCOUNT 4
-
-#define GLAMOR_TICK_AFTER(t0, t1) 	\
-	(((int)(t1) - (int)(t0)) < 0)
-
 typedef struct glamor_screen_private {
-    unsigned int tick;
     enum glamor_gl_flavor gl_flavor;
     int glsl_version;
     Bool has_pack_invert;
@@ -214,10 +205,6 @@ typedef struct glamor_screen_private {
 
     GLuint one_channel_format;
 
-    struct xorg_list
-        fbo_cache[CACHE_FORMAT_COUNT][CACHE_BUCKET_WCOUNT][CACHE_BUCKET_HCOUNT];
-    unsigned long fbo_cache_watermark;
-
     /* glamor point shader */
     glamor_program point_prog;
 
@@ -326,21 +313,10 @@ enum glamor_fbo_state {
 };
 
 typedef struct glamor_pixmap_fbo {
-    struct xorg_list list; /**< linked list pointers when in the fbo cache */
-    /** glamor_priv->tick number when this FBO will be expired from the cache. */
-    unsigned int expire;
     GLuint tex; /**< GL texture name */
     GLuint fb; /**< GL FBO name */
     int width; /**< width in pixels */
     int height; /**< height in pixels */
-    /**
-     * Flag for when texture contents might be shared with a
-     * non-glamor user.
-     *
-     * This is used to avoid putting textures used by other clients
-     * into the FBO cache.
-     */
-    Bool external;
     GLenum format; /**< GL format used to create the texture. */
     GLenum type; /**< GL type used to create the texture. */
 } glamor_pixmap_fbo;
@@ -568,10 +544,7 @@ glamor_pixmap_fbo *glamor_create_fbo(glamor_screen_private *glamor_priv, int w,
 void glamor_destroy_fbo(glamor_screen_private *glamor_priv,
                         glamor_pixmap_fbo *fbo);
 void glamor_pixmap_destroy_fbo(PixmapPtr pixmap);
-void glamor_init_pixmap_fbo(ScreenPtr screen);
-void glamor_fini_pixmap_fbo(ScreenPtr screen);
 Bool glamor_pixmap_fbo_fixup(ScreenPtr screen, PixmapPtr pixmap);
-void glamor_fbo_expire(glamor_screen_private *glamor_priv);
 
 /* Return whether 'picture' is alpha-only */
 static inline Bool glamor_picture_is_alpha(PicturePtr picture)