panfrost: Don't update access with a single batch

drawoverhead test 25 from 462->492

Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21848>

1 files changed, 23 insertions, 4 deletions

diff --git a/src/gallium/drivers/panfrost/pan_job.c b/src/gallium/drivers/panfrost/pan_job.c
index 171f3dc8d78..a318f753ac6 100644
--- a/src/gallium/drivers/panfrost/pan_job.c
+++ b/src/gallium/drivers/panfrost/pan_job.c
@@ -48,6 +48,18 @@ panfrost_batch_idx(struct panfrost_batch *batch)
    return batch - batch->ctx->batches.slots;
 }
 
+static bool
+panfrost_any_batch_other_than(struct panfrost_context *ctx, unsigned index)
+{
+   unsigned i;
+   foreach_batch(ctx, i) {
+      if (i != index)
+         return true;
+   }
+
+   return false;
+}
+
 /* Adds the BO backing surface to a batch if the surface is non-null */
 
 static void
@@ -235,6 +247,17 @@ panfrost_batch_update_access(struct panfrost_batch *batch,
 {
    struct panfrost_context *ctx = batch->ctx;
    uint32_t batch_idx = panfrost_batch_idx(batch);
+
+   if (writes) {
+      _mesa_hash_table_insert(ctx->writers, rsrc, batch);
+   }
+
+   /* The rest of this routine is just about flushing other batches. If there
+    * aren't any, we can skip a lot of work.
+    */
+   if (!panfrost_any_batch_other_than(ctx, batch_idx))
+      return;
+
    struct hash_entry *entry = _mesa_hash_table_search(ctx->writers, rsrc);
    struct panfrost_batch *writer = entry ? entry->data : NULL;
 
@@ -257,10 +280,6 @@ panfrost_batch_update_access(struct panfrost_batch *batch,
             panfrost_batch_submit(ctx, batch);
       }
    }
-
-   if (writes) {
-      _mesa_hash_table_insert(ctx->writers, rsrc, batch);
-   }
 }
 
 static pan_bo_access *