x86/ftrace: Remove mcount support from x86_64
Now that the oldest compiler to build the Linux kernel is gcc 4.6, we no
longer need to support mcount (-pg without -mfentry) as the fentry caller
takes precedence. The build process checks if -mfentry is supported by the
compiler and will use that if it is. The -mfentry option was added to gcc
4.6 for x86_64, and since 4.6 is the oldest compiler to build the Linux
kernel, it will only be build with -mfentry support for x86_64.
There's no reason to keep the mcount code around anymore, as it can't be
built. Removing it simplifies the code.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
1 file changed
