s390/rwlock: use directed yield for write-locked rwlocks
authorMartin Schwidefsky <schwidefsky@de.ibm.com>
Fri, 19 Sep 2014 12:29:31 +0000 (14:29 +0200)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Thu, 25 Sep 2014 08:52:05 +0000 (10:52 +0200)
commitd59b93da5e572703e1a7311c13dd3472a4e56e30
tree4c75073780f54bc9785433256eee3d6d70eaf868
parent46b05c7bd51edafb8c8da088b49bddf7f78d48f9
s390/rwlock: use directed yield for write-locked rwlocks

Add an owner field to the arch_rwlock_t to be able to pass the timeslice
of a virtual CPU with diagnose 0x9c to the lock owner in case the rwlock
is write-locked. The undirected yield in case the rwlock is acquired
writable but the lock is read-locked is removed.

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