linux/include/asm-s390
Martin Schwidefsky ef6edc9746 [PATCH] Directed yield: cpu_relax variants for spinlocks and rw-locks
On systems running with virtual cpus there is optimization potential in
regard to spinlocks and rw-locks.  If the virtual cpu that has taken a lock
is known to a cpu that wants to acquire the same lock it is beneficial to
yield the timeslice of the virtual cpu in favour of the cpu that has the
lock (directed yield).

With CONFIG_PREEMPT="n" this can be implemented by the architecture without
common code changes.  Powerpc already does this.

With CONFIG_PREEMPT="y" the lock loops are coded with _raw_spin_trylock,
_raw_read_trylock and _raw_write_trylock in kernel/spinlock.c.  If the lock
could not be taken cpu_relax is called.  A directed yield is not possible
because cpu_relax doesn't know anything about the lock.  To be able to
yield the lock in favour of the current lock holder variants of cpu_relax
for spinlocks and rw-locks are needed.  The new _raw_spin_relax,
_raw_read_relax and _raw_write_relax primitives differ from cpu_relax
insofar that they have an argument: a pointer to the lock structure.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:21 -07:00
..
a.out.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
appldata.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
atomic.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
auxvec.h [PATCH] auxiliary vector cleanups 2005-09-07 16:57:21 -07:00
bitops.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
bug.h [S390] __builtin_trap() and gcc version. 2006-07-12 16:39:42 +02:00
bugs.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
byteorder.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
cache.h [PATCH] s390: add read_mostly optimization 2006-04-28 08:33:48 -07:00
cacheflush.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ccwdev.h [S390] Fix sparse warnings. 2006-07-12 16:41:55 +02:00
ccwgroup.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
checksum.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
cio.h [S390] ipl/dump on panic. 2006-09-20 15:58:49 +02:00
cmb.h [S390] rework of channel measurement facility. 2006-06-29 15:08:41 +02:00
compat.h [PATCH] s390: add ptr_to_compat() 2006-03-27 08:44:48 -08:00
cpcmd.h [PATCH] s390: add vmcp interface 2005-06-25 16:24:37 -07:00
cputime.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
current.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
dasd.h [S390] add PAV support to the dasd driver. 2006-06-29 15:08:18 +02:00
debug.h [PATCH] Fix 'make headers_check' on s390 2006-09-16 12:54:31 -07:00
delay.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
div64.h [S390] __div64_32 for 31 bit. 2006-09-28 16:55:39 +02:00
dma-mapping.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
dma.h [S390] empty function defines. 2006-09-20 15:58:51 +02:00
ebcdic.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
elf.h [PATCH] Fix 'make headers_check' on s390 2006-09-16 12:54:31 -07:00
emergency-restart.h [PATCH] Add emergency_restart() 2005-07-26 14:35:41 -07:00
errno.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
extmem.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
fcntl.h [PATCH] Clean up struct flock64 definitions 2005-09-07 16:57:38 -07:00
futex.h [S390] Make user-copy operations run-time configurable. 2006-09-20 15:59:42 +02:00
hardirq.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
idals.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
io.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
ioctl.h [PATCH] Generic ioctl.h 2006-01-10 08:01:34 -08:00
ioctls.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ipc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
ipcbuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
irq.h [PATCH] Make touch_nmi_watchdog imply touch_softlockup_watchdog on all archs 2006-09-29 09:18:05 -07:00
irqflags.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
Kbuild [S390] Unexport <asm/z90crypt.h>, export <asm/zcrypt.h> in its place. 2006-09-24 22:07:25 +01:00
kdebug.h [S390] add kprobes support. 2006-09-20 15:58:39 +02:00
kexec.h [PATCH] Kdump: powerpc and s390 build failure fix 2006-01-10 08:01:27 -08:00
kmap_types.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
kprobes.h [S390] add kprobes support. 2006-09-20 15:58:39 +02:00
linkage.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
local.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
lowcore.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
mathemu.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mman.h [PATCH] add asm-generic/mman.h 2006-02-15 15:32:22 -08:00
mmu.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mmu_context.h [PATCH] s390: "extern inline" -> "static inline" 2005-11-09 07:55:52 -08:00
module.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
monwriter.h [S390] Linux API for writing z/VM APPLDATA Monitor records. 2006-09-20 15:59:34 +02:00
msgbuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mutex.h [PATCH] mutex subsystem, add default include/asm-*/mutex.h files 2006-01-09 15:59:19 -08:00
namei.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
page.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
param.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
pci.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
percpu.h [PATCH] trigger a syntax error if percpu macros are incorrectly used 2006-09-26 08:48:44 -07:00
pgalloc.h [S390] Cleanup in page table related code. 2006-09-20 15:59:37 +02:00
pgtable.h [PATCH] convert s390 page handling macros to functions 2006-09-29 09:18:03 -07:00
poll.h [PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications 2006-03-25 08:22:56 -08:00
posix_types.h [S390] __FD_foo definitions. 2006-06-14 14:10:51 +01:00
processor.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
ptrace.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
qdio.h [PATCH] s390: Remove CVS generated information 2006-02-01 08:53:23 -08:00
qeth.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
resource.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
rwsem.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
s390_ext.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
s390_rdev.h [PATCH] s390: email-address change 2006-01-14 18:27:10 -08:00
scatterlist.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sections.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
segment.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
semaphore.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
sembuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
setup.h [S390] Use alternative user-copy operations for new hardware. 2006-09-20 15:59:44 +02:00
sfp-machine.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
shmbuf.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
shmparam.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sigcontext.h [PATCH] s390: sigcontext.h vs __user 2006-01-14 18:27:08 -08:00
siginfo.h [PATCH] consolidate SIGEV_PAD_SIZE 2005-05-01 08:59:08 -07:00
signal.h [PATCH] irq-flags: S390: Use the new IRQF_ constants 2006-07-02 13:58:48 -07:00
sigp.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
smp.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
socket.h [AF_UNIX]: Datagram getpeersec 2006-06-29 16:58:06 -07:00
sockios.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
spinlock.h [PATCH] Directed yield: cpu_relax variants for spinlocks and rw-locks 2006-10-01 00:39:21 -07:00
spinlock_types.h [PATCH] spinlock consolidation 2005-09-10 10:06:21 -07:00
stat.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
statfs.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
string.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
suspend.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
system.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
tape390.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
termbits.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
termios.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
thread_info.h [S390] preempt_count initialization. 2006-06-29 15:02:47 +02:00
timer.h [PATCH] s390: timer interface visibility 2006-02-03 08:32:01 -08:00
timex.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
tlb.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
tlbflush.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
todclk.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
topology.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
types.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
uaccess.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
ucontext.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
unaligned.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
unistd.h [S390] Inline assembly cleanup. 2006-09-28 16:56:43 +02:00
user.h [PATCH] s390: uml ptrace fixes 2005-06-04 17:13:00 -07:00
vtoc.h Use __uXX types for S390 DASD volume label definitions which are user-visible 2006-05-04 01:18:33 +01:00
xor.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
zcrypt.h [S390] zcrypt secure key cryptography extension. 2006-09-20 15:58:36 +02:00