linux/include/asm-arm
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 Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
arch-clps711x [PATCH] simplify update_times (avoid jiffies/jiffies_64 aliasing problem) 2006-09-29 09:18:15 -07:00
arch-ebsa110 [ARM] ebsa110: Fix incorrect serial port address 2006-04-07 13:23:48 +01:00
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 [ARM] Fix decompressor serial IO to give CRLF not LFCR 2006-03-28 10:24:33 +01:00
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 [ARM] Move FLUSH_BASE macros to asm/arch/memory.h 2006-04-07 13:22:21 +01:00
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 [ARM] Move FLUSH_BASE macros to asm/arch/memory.h 2006-04-07 13:22:21 +01:00
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
Kbuild Add empty Kbuild files for 'make headers_install' in remaining arches. 2006-06-18 12:58:53 +01:00
a.out.h
apm.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
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 [PATCH] auxiliary vector cleanups 2005-09-07 16:57:21 -07:00
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 [ARM] Fix byte order macros for Thumb 2006-06-19 15:35:36 +01:00
cache.h [PATCH] Kill L1_CACHE_SHIFT_MAX 2006-01-08 20:13:39 -08:00
cacheflush.h [ARM] Use CPU_CACHE_* where possible in asm/cacheflush.h 2006-09-27 18:00:35 +01:00
checksum.h [ARM] 3292/1: Fix memory corruption in asm-arm/checksum.h: ip_fast_csum() 2006-02-01 19:26:00 +00:00
cpu-multi32.h [PATCH] qualifiers in return types - easy cases 2005-08-23 18:43:45 -07:00
cpu-single.h [PATCH] qualifiers in return types - easy cases 2005-08-23 18:43:45 -07:00
cpu.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
cputime.h
current.h
delay.h [ARM] 3346/1: Fix udelay() for HZ values different from 100 2006-03-21 22:06:07 +00:00
div64.h
dma-mapping.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
dma.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
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 [PATCH] Add emergency_restart() 2005-07-26 14:35:41 -07:00
errno.h
fcntl.h [PATCH] Clean up struct flock64 definitions 2005-09-07 16:57:38 -07:00
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 [PATCH] consolidate asm/futex.h 2006-01-08 20:13:39 -08:00
glue.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
hardirq.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
hardware.h
hw_irq.h [PATCH] ARM: fixup irqflags breakage after ARM genirq merge 2006-07-02 17:29:22 -07:00
ide.h [PATCH] ARM: 2758/1: Fix comment in file header to read "ARM" instead i386 2005-06-27 15:58:39 +01:00
io.h [ARM] 3813/1: prevent >= 4G /dev/mem mmap() 2006-09-25 10:25:26 +01:00
ioctl.h [PATCH] Generic ioctl.h 2006-01-10 08:01:34 -08:00
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
kmap_types.h
leds.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
limits.h
linkage.h
local.h
locks.h [ARM] 3019/1: fix wrong comments 2005-10-18 07:51:34 +01:00
mc146818rtc.h
memory.h [ARM] 3705/1: add supersection support to ioremap() 2006-07-01 19:58:20 +01:00
mman.h [PATCH] add asm-generic/mman.h 2006-02-15 15:32:22 -08:00
mmu.h [ARM] Add section support to ioremap 2006-06-29 22:14:30 +01:00
mmu_context.h [ARM] Add section support to ioremap 2006-06-29 22:14:30 +01:00
mmzone.h
module.h
msgbuf.h
mtd-xip.h [MTD] XIP cleanup 2005-07-07 16:50:16 +02:00
mutex.h [ARM] 3311/1: clean up include/asm-arm/mutex.h 2006-02-08 21:19:38 +00:00
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 [ARM] Move HZ definition into Kconfig 2006-03-21 22:05:45 +00:00
parport.h
pci.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
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 [PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications 2006-03-25 08:22:56 -08:00
posix_types.h
proc-fns.h [ARM] nommu: add ARM946E-S core support 2006-09-27 17:39:19 +01:00
processor.h [ARM] start_thread fixup for nommu mode 2006-01-13 21:04:17 +00:00
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 [PATCH] RTC subsystem: ARM cleanup 2006-03-27 08:44:50 -08:00
scatterlist.h [ARM] Remove '__address' from scatterlist and convert to DMA API 2006-01-04 15:08:30 +00:00
sections.h
segment.h
semaphore-helper.h
semaphore.h [ARM] sema_count() removal 2005-12-01 20:58:01 +00:00
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 Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
socket.h [AF_UNIX]: Datagram getpeersec 2006-06-29 16:58:06 -07:00
sockios.h
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 [ARM] 3106/2: ARM EABI: some syscall adjustments 2006-01-14 16:32:12 +00:00
statfs.h [ARM] 3108/2: old ABI compat: statfs64 and fstatfs64 2006-01-14 16:35:03 +00:00
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 [ARM] noMMU: removes TLB codes in nommu mode 2006-03-21 22:03:20 +00:00
tlbflush.h [ARM] 3759/2: Remove uses of %? 2006-09-20 14:58:35 +01:00
topology.h
traps.h
types.h [PATCH] sab: consolidate kmem_bufctl_t 2005-09-05 00:05:48 -07:00
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 [ARM] 3472/1: Use the D variants of FLDMIA/FSTMIA on ARMv6 2006-04-10 21:32:42 +01:00
vga.h [PATCH] vgacon: make VGA_MAP_MEM take size, remove extra use 2006-06-22 15:05:58 -07:00
xor.h