x86/xen: Move hypercall_page to top of the file
Because hypercall_page is page-aligned, the assembler inexplicably adds
an unreachable jump from after the end of the previous code to the
beginning of hypercall_page.
That confuses objtool, understandably. It also creates significant text
fragmentation. As a result, much of the object file is wasted text
(nops).
Move hypercall_page to the beginning of the file to both prevent the
text fragmentation and avoid the dead jump instruction.
$ size /tmp/head_64.before.o /tmp/head_64.after.o
text data bss dec hex filename
10924 307252 4096 322272 4eae0 /tmp/head_64.before.o
6823 307252 4096 318171 4dadb /tmp/head_64.after.o
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20210820193107.omvshmsqbpxufzkc@treble