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
..
arch-aaec2000	[ARM] 3631/1: Remove legacy __mem_isa() definitions	2006-06-24 10:34:48 +01:00
arch-at91rm9200	[ARM] 3870/1: AT91: Start removing static memory mappings	2006-09-28 18:11:22 +01:00
arch-cl7500
arch-clps711x	[PATCH] simplify update_times (avoid jiffies/jiffies_64 aliasing problem)	2006-09-29 09:18:15 -07:00
arch-ebsa110
arch-ebsa285	[ARM] 3631/1: Remove legacy __mem_isa() definitions	2006-06-24 10:34:48 +01:00
arch-ep93xx	[PATCH] Cirrus Logic ep93xx ethernet driver	2006-09-22 20:13:23 -04:00
arch-h720x	[ARM] 3660/1: Remove legacy defines	2006-06-28 17:54:55 +01:00
arch-imx	[ARM] 3660/1: Remove legacy defines	2006-06-28 17:54:55 +01:00
arch-integrator	[ARM] 3631/1: Remove legacy __mem_isa() definitions	2006-06-24 10:34:48 +01:00
arch-iop32x	[ARM] 3851/1: iop3xx: add io-data glantank support	2006-09-25 10:34:02 +01:00
arch-iop33x	[ARM] 3832/1: iop3xx: coding style cleanup	2006-09-25 10:25:53 +01:00
arch-ixp4xx	[ARM] 3856/1: Add clocksource for Intel IXP4xx platforms	2006-09-28 20:59:25 +01:00
arch-ixp23xx	[ARM] 3662/1: ixp23xx: don't include asm/hardware.h in uncompress.h	2006-06-28 17:54:56 +01:00
arch-ixp2000
arch-l7200	[PATCH] simplify update_times (avoid jiffies/jiffies_64 aliasing problem)	2006-09-29 09:18:15 -07:00
arch-lh7a40x	[ARM] 3631/1: Remove legacy __mem_isa() definitions	2006-06-24 10:34:48 +01:00
arch-netx	[ARM] 3631/1: Remove legacy __mem_isa() definitions	2006-06-24 10:34:48 +01:00
arch-omap	[PATCH] OMAP: Add keypad driver	2006-09-29 09:18:07 -07:00
arch-pnx4008	[ARM] 3621/1: fix compilation breakage for pnx4008	2006-06-22 10:27:15 +01:00
arch-pxa	USB: pxa2xx_udc understands GPIO based VBUS sensing	2006-09-27 11:58:48 -07:00
arch-realview	[ARM] 3631/1: Remove legacy __mem_isa() definitions	2006-06-24 10:34:48 +01:00
arch-rpc
arch-s3c2410	[ARM] 3846/1: S3C24XX: Fix osiris memory map	2006-09-25 10:33:59 +01:00
arch-sa1100	[ARM] 3631/1: Remove legacy __mem_isa() definitions	2006-06-24 10:34:48 +01:00
arch-shark
arch-versatile	[ARM] Allow Versatile to be built for AB and PB	2006-07-11 21:10:42 +01:00
hardware	[ARM] 3864/1: Refactore sharpsl_pm	2006-09-27 20:59:22 +01:00
mach	[ARM] 3855/1: Add generic time support	2006-09-28 20:59:24 +01:00
a.out.h
apm.h
assembler.h	[ARM] Remove MODE_(SVC|IRQ|FIQ|USR) and DEFAULT_FIQ	2006-06-25 12:01:48 +01:00
atomic.h	[ARM] 3810/1: switch atomic helpers over to raw_local_irq_{save,restore}	2006-09-25 10:25:24 +01:00
auxvec.h
bitops.h	[ARM] 3852/1: convert atomic bitops and __xchg over to raw_local_irq_{save,restore}	2006-09-25 10:34:03 +01:00
bug.h	Remove obsolete #include <linux/config.h>	2006-06-30 19:25:36 +02:00
bugs.h	[ARM] nommu: adjust headers for !MMU ARM systems	2006-06-28 17:59:45 +01:00
byteorder.h
cache.h
cacheflush.h	[ARM] Use CPU_CACHE_* where possible in asm/cacheflush.h	2006-09-27 18:00:35 +01:00
checksum.h
cpu-multi32.h
cpu-single.h
cpu.h
cputime.h
current.h
delay.h
div64.h
dma-mapping.h
dma.h
domain.h	[ARM] nommu: adjust headers for !MMU ARM systems	2006-06-28 17:59:45 +01:00
dyntick.h	[ARM] 3692/1: ARM: coswitch irq handling to the generic implementation	2006-07-01 22:30:09 +01:00
ecard.h
elf.h	[HEADERS] Fix ARM 'make headers_check'	2006-09-21 08:34:39 +01:00
emergency-restart.h
errno.h
fcntl.h
fiq.h
flat.h	[ARM] nommu: create flat.h to support uClinux flat binaries	2006-09-20 14:58:35 +01:00
floppy.h	[PATCH] ARM: fixup irqflags breakage after ARM genirq merge	2006-07-02 17:29:22 -07:00
fpstate.h	[ARM] 3370/2: ep93xx: add crunch support	2006-06-28 17:55:01 +01:00
futex.h
glue.h
hardirq.h
hardware.h
hw_irq.h	[PATCH] ARM: fixup irqflags breakage after ARM genirq merge	2006-07-02 17:29:22 -07:00
ide.h
io.h	[ARM] 3813/1: prevent >= 4G /dev/mem mmap()	2006-09-25 10:25:26 +01:00
ioctl.h
ioctls.h
ipc.h
ipcbuf.h
irq.h	[ARM] 3692/1: ARM: coswitch irq handling to the generic implementation	2006-07-01 22:30:09 +01:00
irqflags.h	[ARM] Add ARM irqtrace support	2006-09-20 14:58:35 +01:00
Kbuild
kmap_types.h
leds.h
limits.h
linkage.h
local.h
locks.h
mc146818rtc.h
memory.h	[ARM] 3705/1: add supersection support to ioremap()	2006-07-01 19:58:20 +01:00
mman.h
mmu_context.h	[ARM] Add section support to ioremap	2006-06-29 22:14:30 +01:00
mmu.h	[ARM] Add section support to ioremap	2006-06-29 22:14:30 +01:00
mmzone.h
module.h
msgbuf.h
mtd-xip.h
mutex.h
namei.h
nwflash.h
page-nommu.h	[ARM] nommu: adjust headers for !MMU ARM systems	2006-06-28 17:59:45 +01:00
page.h	Merge master.kernel.org:/pub/scm/linux/kernel/git/tmlind/linux-omap-upstream into devel	2006-09-27 19:57:54 +01:00
param.h
parport.h
pci.h
percpu.h
pgalloc.h	[ARM] nommu: adjust headers for !MMU ARM systems	2006-06-28 17:59:45 +01:00
pgtable-hwdef.h	[ARM] Set bit 4 on section mappings correctly depending on CPU	2006-06-29 18:24:21 +01:00
pgtable-nommu.h	[ARM] nommu: adjust headers for !MMU ARM systems	2006-06-28 17:59:45 +01:00
pgtable.h	Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm	2006-09-28 14:40:39 -07:00
poll.h
posix_types.h
proc-fns.h	[ARM] nommu: add ARM946E-S core support	2006-09-27 17:39:19 +01:00
processor.h
procinfo.h	[ARM] 3756/1: Assign value for HWCAP_IWMMXT	2006-08-18 15:32:17 +01:00
ptrace.h	[ARM] 3665/1: crunch: add ptrace support	2006-06-28 17:55:00 +01:00
resource.h
rtc.h
scatterlist.h
sections.h
segment.h
semaphore-helper.h
semaphore.h
sembuf.h
serial.h
setup.h	[ARM] Separate page table manipulation code from bootmem initialisation	2006-09-27 10:10:58 +01:00
shmbuf.h
shmparam.h
sigcontext.h
siginfo.h
signal.h	[PATCH] ARM: fixup irqflags breakage after ARM genirq merge	2006-07-02 17:29:22 -07:00
sizes.h
smp.h
socket.h	[AF_UNIX]: Datagram getpeersec	2006-06-29 16:58:06 -07:00
sockios.h
spinlock_types.h
spinlock.h	[PATCH] Directed yield: cpu_relax variants for spinlocks and rw-locks	2006-10-01 00:39:21 -07:00
stat.h
statfs.h
string.h
suspend.h
system.h	[ARM] nommu: manage the CP15 things	2006-09-27 17:34:30 +01:00
termbits.h
termios.h
therm.h
thread_info.h	Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm	2006-07-02 15:04:12 -07:00
thread_notify.h	[ARM] Add thread_notify infrastructure	2006-06-22 10:24:18 +01:00
timeofday.h	[ARM] 3855/1: Add generic time support	2006-09-28 20:59:24 +01:00
timex.h
tlb.h
tlbflush.h	[ARM] 3759/2: Remove uses of %?	2006-09-20 14:58:35 +01:00
topology.h
traps.h
types.h
uaccess.h	[ARM] nommu: uaccess tweaks	2006-06-28 17:59:46 +01:00
ucontext.h	[ARM] 3664/1: crunch: add signal frame save/restore	2006-06-28 17:54:59 +01:00
unaligned.h	[ARM] 3849/1: fix get_unaligned() for gcc >= 4.1	2006-09-25 10:34:00 +01:00
unistd.h	[PATCH] consistently use MAX_ERRNO in __syscall_return	2006-09-27 08:26:18 -07:00
user.h
vfp.h
vfpmacros.h
vga.h	[PATCH] vgacon: make VGA_MAP_MEM take size, remove extra use	2006-06-22 15:05:58 -07:00
xor.h