u_debug_refcnt: Don't loop for initial refcounts if the initial value is huge

Some components use very large refcounts to bypass atomics in single-threaded
cases, and this produces near-infinite loops when these resources are created.

Reviewed-by: Sil Vilerino <sivileri@microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16182>

diff --git a/src/util/u_debug_refcnt.c b/src/util/u_debug_refcnt.c
index 06498eb..566fb9c 100644 (file)
--- a/src/util/u_debug_refcnt.c
+++ b/src/util/u_debug_refcnt.c
@@ -174,10 +174,12 @@ debug_reference_slowpath(const struct pipe_reference *p,
          /* this is here to provide a gradual change even if we don't see
           * the initialization
           */
-         for (i = 1; i <= refcnt - change; ++i) {
-            fprintf(stream, "<%s> %p %u AddRef %u\n", buf, (void *) p,
-                    serial, i);
-            debug_backtrace_print(stream, frames, STACK_LEN);
+         if (refcnt <= 10) {
+            for (i = 1; i <= refcnt - change; ++i) {
+               fprintf(stream, "<%s> %p %u AddRef %u\n", buf, (void *) p,
+                  serial, i);
+               debug_backtrace_print(stream, frames, STACK_LEN);
+            }
          }
       }