s390/spinlock: remove compare and delay instruction
authorMartin Schwidefsky <schwidefsky@de.ibm.com>
Fri, 24 Mar 2017 16:00:45 +0000 (17:00 +0100)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Wed, 12 Apr 2017 06:43:33 +0000 (08:43 +0200)
commitb13de4b7adeb7a5e37a5aa78d5a4926c3cd4e131
tree472c2bdb751e5529b403dd297b76ae08f25a7d9a
parent02c503ff237cdcd8e012a122a638295550db10a5
s390/spinlock: remove compare and delay instruction

The CAD instruction never worked quite as expected for the spinlock
code. It has been disabled by default with git commit 61b0b01686d48220,
if the "cad" kernel parameter is specified it is enabled for both user
space and the spinlock code. Leave the option to enable the instruction
for user space but remove it from the spinlock code.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
arch/s390/include/asm/setup.h
arch/s390/kernel/early.c
arch/s390/lib/spinlock.c