diff --git a/openmp/libomptarget/deviceRTLs/amdgcn/src/target_impl.hip b/openmp/libomptarget/deviceRTLs/amdgcn/src/target_impl.hip
--- a/openmp/libomptarget/deviceRTLs/amdgcn/src/target_impl.hip
+++ b/openmp/libomptarget/deviceRTLs/amdgcn/src/target_impl.hip
@@ -56,7 +56,7 @@
 {
   __atomic_thread_fence(__ATOMIC_ACQUIRE);
 
-  uint32_t num_waves = num_threads / WARPSIZE;
+  uint32_t num_waves = (num_threads + WARPSIZE - 1) / WARPSIZE;
 
   // Partial barrier implementation for amdgcn.
   // Uses two 16 bit unsigned counters. One for the number of waves to have