present: Add present_vblank::exec_msc field

For tracking the MSC when the present can be executed separately from
the target MSC.

Allows removing the requeue field instead, plus more later.

v2:
* Rename wait_msc → exec_msc (Roman Gilg)
* Use exec_msc = target_msc instead of exec_msc++, for clarity.
* Bug fix: Set exec_msc = target_msc also if present_flip returned
  false in present_execute.
v3:
* Set exec_msc = target_msc also if present_wnmd_flip returned
  false in present_wnmd_execute, for consistency.
v4:
* Specifically check for exec_msc == crtc_msc + 1 in
  present_execute_wait/copy, to avoid re-introducing
  https://bugs.freedesktop.org/show_bug.cgi?id=94596 .

Reviewed-by: Roman Gilg <subdiff@gmail.com>
Tested-by: Roman Gilg <subdiff@gmail.com>

5 files changed, 31 insertions, 31 deletions

diff --git a/present/present_execute.c b/present/present_execute.c
index 8d1ef4a8c..58066db86 100644
--- a/present/present_execute.c
+++ b/present/present_execute.c
@@ -48,16 +48,13 @@ present_execute_wait(present_vblank_ptr vblank, uint64_t crtc_msc)
     ScreenPtr                   screen = window->drawable.pScreen;
     present_screen_priv_ptr screen_priv = present_screen_priv(screen);
 
-    if (vblank->requeue) {
-        vblank->requeue = FALSE;
-        if (msc_is_after(vblank->target_msc, crtc_msc) &&
-            Success == screen_priv->queue_vblank(screen,
-                                                 window,
-                                                 vblank->crtc,
-                                                 vblank->event_id,
-                                                 vblank->target_msc))
-            return TRUE;
-    }
+    /* We may have to requeue for the next MSC if check_flip_window prevented
+     * using a flip.
+     */
+    if (vblank->exec_msc == crtc_msc + 1 &&
+        screen_priv->queue_vblank(screen, window, vblank->crtc, vblank->event_id,
+                                  vblank->exec_msc) == Success)
+        return TRUE;
 
     if (vblank->wait_fence) {
         if (!present_fence_check_triggered(vblank->wait_fence)) {
@@ -75,13 +72,13 @@ present_execute_copy(present_vblank_ptr vblank, uint64_t crtc_msc)
     ScreenPtr                   screen = window->drawable.pScreen;
     present_screen_priv_ptr screen_priv = present_screen_priv(screen);
 
-    /* If present_flip failed, we may have to requeue for the target MSC */
-    if (vblank->target_msc == crtc_msc + 1 &&
+    /* If present_flip failed, we may have to requeue for the next MSC */
+    if (vblank->exec_msc == crtc_msc + 1 &&
         Success == screen_priv->queue_vblank(screen,
                                              window,
                                              vblank->crtc,
                                              vblank->event_id,
-                                             vblank->target_msc)) {
+                                             vblank->exec_msc)) {
         vblank->queued = TRUE;
         return;
     }
diff --git a/present/present_priv.h b/present/present_priv.h
index 7f9d82d8d..bce67b21e 100644
--- a/present/present_priv.h
+++ b/present/present_priv.h
@@ -70,14 +70,14 @@ struct present_vblank {
     int16_t             y_off;
     CARD16              kind;
     uint64_t            event_id;
-    uint64_t            target_msc;
+    uint64_t            target_msc;     /* target MSC when present should complete */
+    uint64_t            exec_msc;       /* MSC at which present can be executed */
     uint64_t            msc_offset;
     present_fence_ptr   idle_fence;
     present_fence_ptr   wait_fence;
     present_notify_ptr  notifies;
     int                 num_notifies;
     Bool                queued;         /* on present_exec_queue */
-    Bool                requeue;        /* on queue, but target_msc has changed */
     Bool                flip;           /* planning on using flip */
     Bool                flip_ready;     /* wants to flip, but waiting for previous flip or unflip */
     Bool                flip_idler;     /* driver explicitly permitted idling */
diff --git a/present/present_scmd.c b/present/present_scmd.c
index a5a36f2a2..c7184e793 100644
--- a/present/present_scmd.c
+++ b/present/present_scmd.c
@@ -335,8 +335,8 @@ present_flip_notify(present_vblank_ptr vblank, uint64_t ust, uint64_t crtc_msc)
     ScreenPtr                   screen = vblank->screen;
     present_screen_priv_ptr     screen_priv = present_screen_priv(screen);
 
-    DebugPresent(("\tn %" PRIu64 " %p %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 "\n",
-                  vblank->event_id, vblank, vblank->target_msc,
+    DebugPresent(("\tn %" PRIu64 " %p %" PRIu64 " %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 "\n",
+                  vblank->event_id, vblank, vblank->exec_msc, vblank->target_msc,
                   vblank->pixmap ? vblank->pixmap->drawable.id : 0,
                   vblank->window ? vblank->window->drawable.id : 0));
 
@@ -456,7 +456,7 @@ present_check_flip_window (WindowPtr window)
             vblank->flip = FALSE;
             vblank->reason = reason;
             if (vblank->sync_flip)
-                vblank->requeue = TRUE;
+                vblank->exec_msc = vblank->target_msc;
         }
     }
 }
@@ -582,6 +582,7 @@ present_execute(present_vblank_ptr vblank, uint64_t ust, uint64_t crtc_msc)
               */
             screen_priv->flip_pending = NULL;
             vblank->flip = FALSE;
+            vblank->exec_msc = vblank->target_msc;
         }
         DebugPresent(("\tc %p %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 "\n",
                       vblank, crtc_msc, vblank->pixmap->drawable.id, vblank->window->drawable.id));
@@ -739,12 +740,12 @@ present_scmd_pixmap(WindowPtr window,
         return BadAlloc;
 
     if (vblank->flip && vblank->sync_flip)
-        target_msc--;
+        vblank->exec_msc--;
 
     xorg_list_append(&vblank->event_queue, &present_exec_queue);
     vblank->queued = TRUE;
-    if (msc_is_after(target_msc, crtc_msc)) {
-        ret = present_queue_vblank(screen, window, target_crtc, vblank->event_id, target_msc);
+    if (msc_is_after(vblank->exec_msc, crtc_msc)) {
+        ret = present_queue_vblank(screen, window, target_crtc, vblank->event_id, vblank->exec_msc);
         if (ret == Success)
             return Success;
 
diff --git a/present/present_vblank.c b/present/present_vblank.c
index a4b70c0d9..af14fe134 100644
--- a/present/present_vblank.c
+++ b/present/present_vblank.c
@@ -101,6 +101,7 @@ present_vblank_create(WindowPtr window,
     vblank->x_off = x_off;
     vblank->y_off = y_off;
     vblank->target_msc = target_msc;
+    vblank->exec_msc = target_msc;
     vblank->crtc = target_crtc;
     vblank->msc_offset = window_priv->msc_offset;
     vblank->notifies = notifies;
@@ -152,8 +153,8 @@ no_mem:
 void
 present_vblank_scrap(present_vblank_ptr vblank)
 {
-    DebugPresent(("\tx %" PRIu64 " %p %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 " (crtc %p)\n",
-                  vblank->event_id, vblank, vblank->target_msc,
+    DebugPresent(("\tx %" PRIu64 " %p %" PRIu64 " %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 " (crtc %p)\n",
+                  vblank->event_id, vblank, vblank->exec_msc, vblank->target_msc,
                   vblank->pixmap->drawable.id, vblank->window->drawable.id,
                   vblank->crtc));
 
@@ -174,8 +175,8 @@ present_vblank_destroy(present_vblank_ptr vblank)
     /* Also make sure vblank is removed from event queue (wnmd) */
     xorg_list_del(&vblank->event_queue);
 
-    DebugPresent(("\td %" PRIu64 " %p %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 "\n",
-                  vblank->event_id, vblank, vblank->target_msc,
+    DebugPresent(("\td %" PRIu64 " %p %" PRIu64 " %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 "\n",
+                  vblank->event_id, vblank, vblank->exec_msc, vblank->target_msc,
                   vblank->pixmap ? vblank->pixmap->drawable.id : 0,
                   vblank->window ? vblank->window->drawable.id : 0));
 
diff --git a/present/present_wnmd.c b/present/present_wnmd.c
index 922b877e7..f97083f7b 100644
--- a/present/present_wnmd.c
+++ b/present/present_wnmd.c
@@ -158,8 +158,8 @@ present_wnmd_flip_notify_vblank(present_vblank_ptr vblank, uint64_t ust, uint64_
     WindowPtr                   window = vblank->window;
     present_window_priv_ptr     window_priv = present_window_priv(window);
 
-    DebugPresent(("\tn %" PRIu64 " %p %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 "\n",
-                  vblank->event_id, vblank, vblank->target_msc,
+    DebugPresent(("\tn %" PRIu64 " %p %" PRIu64 " %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 "\n",
+                  vblank->event_id, vblank, vblank->exec_msc, vblank->target_msc,
                   vblank->pixmap ? vblank->pixmap->drawable.id : 0,
                   vblank->window ? vblank->window->drawable.id : 0));
 
@@ -359,7 +359,7 @@ present_wnmd_check_flip_window (WindowPtr window)
             vblank->flip = FALSE;
             vblank->reason = reason;
             if (vblank->sync_flip)
-                vblank->requeue = TRUE;
+                vblank->exec_msc = vblank->target_msc;
         }
     }
 }
@@ -507,6 +507,7 @@ present_wnmd_execute(present_vblank_ptr vblank, uint64_t ust, uint64_t crtc_msc)
               */
             window_priv->flip_pending = NULL;
             vblank->flip = FALSE;
+            vblank->exec_msc = vblank->target_msc;
         }
         DebugPresent(("\tc %p %" PRIu64 ": %08" PRIx32 " -> %08" PRIx32 "\n",
                       vblank, crtc_msc, vblank->pixmap->drawable.id, vblank->window->drawable.id));
@@ -651,12 +652,12 @@ present_wnmd_pixmap(WindowPtr window,
         return BadAlloc;
 
     if (vblank->flip && vblank->sync_flip)
-        target_msc--;
+        vblank->exec_msc--;
 
     xorg_list_append(&vblank->event_queue, &window_priv->exec_queue);
     vblank->queued = TRUE;
-    if (crtc_msc < target_msc) {
-        if (present_wnmd_queue_vblank(screen, window, target_crtc, vblank->event_id, target_msc) == Success) {
+    if (crtc_msc < vblank->exec_msc) {
+        if (present_wnmd_queue_vblank(screen, window, target_crtc, vblank->event_id, vblank->exec_msc) == Success) {
             return Success;
         }
         DebugPresent(("present_queue_vblank failed\n"));