amdgcn, openmp: Fix concurrency in low-latency allocator

The previous code works fine on Fiji and Vega 10 devices, but bogs down in The
spin locks on Vega 20 or newer.  Adding the sleep instructions fixes the
problem.

libgomp/ChangeLog:

	* basic-allocator.c (basic_alloc_free): Use BASIC_ALLOC_YIELD.
	(basic_alloc_realloc): Use BASIC_ALLOC_YIELD.

2 files changed, 7 insertions, 0 deletions

diff --git a/libgomp/ChangeLog.omp b/libgomp/ChangeLog.omp
index 09cf9c6..32bc3b0 100644
--- a/libgomp/ChangeLog.omp
+++ b/libgomp/ChangeLog.omp
@@ -1,3 +1,8 @@
+2023-04-20  Andrew Stubbs  <ams@codesourcery.com>
+
+	* basic-allocator.c (basic_alloc_free): Use BASIC_ALLOC_YIELD.
+	(basic_alloc_realloc): Use BASIC_ALLOC_YIELD.
+
 2023-04-03  Thomas Schwinge  <thomas@codesourcery.com>
 
 	* target.c (gomp_map_vars_internal)
diff --git a/libgomp/basic-allocator.c b/libgomp/basic-allocator.c
index b4b9e4b..a61828e 100644
--- a/libgomp/basic-allocator.c
+++ b/libgomp/basic-allocator.c
@@ -188,6 +188,7 @@ basic_alloc_free (char *heap, void *addr, size_t size)
 	  break;
 	}
       /* Spin.  */
+      BASIC_ALLOC_YIELD;
     }
   while (1);
 
@@ -267,6 +268,7 @@ basic_alloc_realloc (char *heap, void *addr, size_t oldsize,
 	  break;
 	}
       /* Spin.  */
+      BASIC_ALLOC_YIELD;
     }
   while (1);