systemtap-sdt: init (#392921)

pkgs/by-name/gl/glib/package.nix

@@ -65,7 +65,7 @@ let
     else
       "2.0-0.lib";
 
-  systemtap' = buildPackages.linuxPackages.systemtap.override { withStap = false; };
+  systemtap' = buildPackages.systemtap-sdt;
 
   withDtrace =
     lib.meta.availableOn stdenv.buildPlatform systemtap'

pkgs/by-name/sy/systemtap-sdt/package.nix

@@ -0,0 +1,10 @@
+{ linuxPackages }:
+linuxPackages.systemtap.override {
+  withStap = false;
+}
+// {
+  meta = linuxPackages.systemtap.meta // {
+    description = "Build USDT tracepoints with the 'dtrace' executable on Linux";
+    mainProgram = "dtrace";
+  };
+}

pkgs/development/tools/profiling/systemtap/default.nix

@@ -11,7 +11,7 @@
   gnumake,
   python3,
   nixosTests,
-  withStap ? true, # avoid cyclic dependency with glib
+  withStap ? true, # avoid cyclic dependency with glib, reduce closure size substantially
 }:
 
 let