xtensa: Emulate two-byte cmpxchg

Xtensa has no two-byte atomic compare and swap, so the __cmpxchg()
switch lets case 2 fall through to __cmpxchg_called_with_bad_pointer(),
which is declared but never defined, so a two-byte cmpxchg() fails
at link time.

Route case 2 through the new cmpxchg_emu_u16(), which takes the
old and new values as unsigned long and narrows them itself, so
the call needs no extra casts.

Signed-off-by: Bradley Morgan <brads@mainlining.org>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

0 files changed, 0 insertions, 0 deletions