s390/spinlock: add compare-and-delay to lock wait loops

Browse source

Add the compare-and-delay instruction to the spin-lock and rw-lock
retry loops. A CPU executing the compare-and-delay instruction stops
until the lock value has changed. This is done to make the locking
code for contended locks to behave better in regard to the multi-
hreading facility. A thread of a core executing a compare-and-delay
will allow the other threads of a core to get a larger share of the
core resources.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

...

This commit is contained in:

Martin Schwidefsky 2015-01-14 17:52:33 +01:00

parent 55b5eb75e7

commit 2c72a44ecd

3 changed files with 66 additions and 7 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

3

arch/s390/include/asm/setup.h

View file

18

arch/s390/kernel/early.c

View file

52

arch/s390/lib/spinlock.c

View file