kbuild: dummy-tools: pretend we understand -fpatchable-function-entry

Commit 0f71dcfb4aef ("powerpc/ftrace: Add support for
-fpatchable-function-entry") added a script to check for
-fpatchable-function-entry compiler support. The script expects compiler
to emit the section __patchable_function_entries and few nops after a
function entry.

If the compiler understands and emits the above,
CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY is set.

So teach dummy-tools' gcc about this.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

diff --git a/scripts/dummy-tools/gcc b/scripts/dummy-tools/gcc
index 07f6dc4c5cf695c7c23a5ca9964c313953eb13a8..e6c41427c02f32a01861ee74e6797fe8719e415c 100755 (executable)
--- a/scripts/dummy-tools/gcc
+++ b/scripts/dummy-tools/gcc
@@ -91,6 +91,16 @@ if arg_contain -S "$@"; then
                fi
                exit 0
        fi
+
+       # For arch/powerpc/tools/gcc-check-fpatchable-function-entry.sh
+       if arg_contain -m64 "$@" && arg_contain -fpatchable-function-entry=2 "$@"; then
+               echo "func:"
+               echo ".section __patchable_function_entries"
+               echo ".localentry"
+               echo "  nop"
+               echo "  nop"
+               exit 0
+       fi
 fi
 
 # To set GCC_PLUGINS