Mesa (main): panfrost: Avoid duplicate entries in access->readers

[GitLab Mirror]

Module: Mesa
Branch: main
Commit: 82571f977ae0cf927f65df85e683a211cf7b077e
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=82571f977ae0cf927f65df85e683a211cf7b077e

Author: Boris Brezillon <boris.brezillon at collabora.com>
Date:   Wed May 12 13:24:03 2021 +0200

panfrost: Avoid duplicate entries in access->readers

The PAN_BATCH_DEBUG section was too wide, potentially leading to
double insertion of the same batch in the readers array. Let's get rid
of this already_accessed parameter and make sure
panfrost_batch_update_bo_access() is only called if the RW flags have
changed.

Signed-off-by: Boris Brezillon <boris.brezillon at collabora.com>
Reviewed-by:  Alyssa Rosenzweig <alyssa at collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10842>

---

 src/gallium/drivers/panfrost/pan_job.c | 37 ++++++++--------------------------
 1 file changed, 8 insertions(+), 29 deletions(-)

diff --git a/src/gallium/drivers/panfrost/pan_job.c b/src/gallium/drivers/panfrost/pan_job.c
index d61567d28fe..5096a836cc4 100644
--- a/src/gallium/drivers/panfrost/pan_job.c
+++ b/src/gallium/drivers/panfrost/pan_job.c
@@ -397,25 +397,9 @@ panfrost_gc_fences(struct panfrost_context *ctx)
         }
 }
 
-#ifdef PAN_BATCH_DEBUG
-static bool
-panfrost_batch_in_readers(struct panfrost_batch *batch,
-                          struct panfrost_bo_access *access)
-{
-        util_dynarray_foreach(&access->readers, struct panfrost_batch_fence *,
-                              reader) {
-                if (*reader && (*reader)->batch == batch)
-                        return true;
-        }
-
-        return false;
-}
-#endif
-
 static void
 panfrost_batch_update_bo_access(struct panfrost_batch *batch,
-                                struct panfrost_bo *bo, bool writes,
-                                bool already_accessed)
+                                struct panfrost_bo *bo, bool writes)
 {
         struct panfrost_context *ctx = batch->ctx;
         struct panfrost_bo_access *access;
@@ -507,16 +491,6 @@ panfrost_batch_update_bo_access(struct panfrost_batch *batch,
                                              batch->out_sync);
                 }
         } else {
-                /* We already accessed this BO before, so we should already be
-                 * in the reader array.
-                 */
-#ifdef PAN_BATCH_DEBUG
-                if (already_accessed) {
-                        assert(panfrost_batch_in_readers(batch, access));
-                        return;
-                }
-#endif
-
                 /* Previous access was a read and we want to read this BO.
                  * Add ourselves to the readers array and add a dependency on
                  * the previous writer if any.
@@ -570,9 +544,14 @@ panfrost_batch_add_bo(struct panfrost_batch *batch, struct panfrost_bo *bo,
         if (!(flags & PAN_BO_ACCESS_SHARED))
                 return;
 
+        /* RW flags didn't change since our last access, no need to update the
+         * BO access entry.
+         */
+        if ((old_flags & PAN_BO_ACCESS_RW) == (flags & PAN_BO_ACCESS_RW))
+                return;
+
         assert(flags & PAN_BO_ACCESS_RW);
-        panfrost_batch_update_bo_access(batch, bo, flags & PAN_BO_ACCESS_WRITE,
-                        old_flags != 0);
+        panfrost_batch_update_bo_access(batch, bo, flags & PAN_BO_ACCESS_WRITE);
 }
 
 static void