1 files changed, 16 insertions, 21 deletions

diff --git a/libsmctrl.c b/libsmctrl.c
index 5a45611..5ee94fb 100644
--- a/libsmctrl.c
+++ b/libsmctrl.c
@@ -119,10 +119,23 @@ static void setup_sm_control_callback() {
         int (*enable)(uint32_t enable, uint32_t hndl, int domain, int cbid);
         uintptr_t* tbl_base;
         uint32_t my_hndl;
-        // Avoid race conditions (setup can only be called once)
+        // Avoid race conditions (setup should only run once)
         if (__atomic_test_and_set(&sm_control_setup_called, __ATOMIC_SEQ_CST))
                 return;
 
+#if CUDA_VERSION <= 6050
+        // Verify supported CUDA version
+        // It's impossible for us to run with a version of CUDA older than we were
+        // built by, so this check is excluded if built with CUDA > 6.5.
+        int ver = 0;
+        cuDriverGetVersion(&ver);
+        if (ver < 6050)
+                abort(1, ENOSYS, "Global or next masking requires at least CUDA 6.5; "
+                                 "this application is using CUDA %d.%d",
+                                 ver / 1000, (ver % 100));
+#endif
+
+        // Set up callback
         cuGetExportTable((const void**)&tbl_base, &callback_funcs_id);
         uintptr_t subscribe_func_addr = *(tbl_base + 3);
         uintptr_t enable_func_addr = *(tbl_base + 6);
@@ -139,31 +152,13 @@ static void setup_sm_control_callback() {
 
 // Set default mask for all launches
 void libsmctrl_set_global_mask(uint64_t mask) {
-        if (!sm_control_setup_called) {
-                // The version will not change while running, so only check once
-                int ver = 0;
-                cuDriverGetVersion(&ver);
-                if (ver < 6050)
-                        abort(1, ENOSYS, "Global masking requires at least CUDA 6.5; "
-                                         "this application is using CUDA %d.%d",
-                                         ver / 1000, (ver % 100));
-                setup_sm_control_callback();
-        }
+        setup_sm_control_callback();
         g_sm_mask = mask;
 }
 
 // Set mask for next launch from this thread
 void libsmctrl_set_next_mask(uint64_t mask) {
-        if (!sm_control_setup_called) {
-                // The version will not change while running, so only check once
-                int ver = 0;
-                cuDriverGetVersion(&ver);
-                if (ver < 6050)
-                        abort(1, ENOSYS, "Next masking requires at least CUDA 6.5; "
-                                         "this application is using CUDA %d.%d",
-                                         ver / 1000, (ver % 100));
-                setup_sm_control_callback();
-        }
+        setup_sm_control_callback();
         g_next_sm_mask = mask;
 }