Russell King 112f38a4a3 ARM: sched_clock: provide common infrastructure for sched_clock() ... Provide common sched_clock() infrastructure for platforms to use to create a 64-bit ns based sched_clock() implementation from a counter running at a non-variable clock rate. This implementation is based upon maintaining an epoch for the counter and an epoch for the nanosecond time. When we desire a sched_clock() time, we calculate the number of counter ticks since the last epoch update, convert this to nanoseconds and add to the epoch nanoseconds. We regularly refresh these epochs within the counter wrap interval. We perform a similar calculation as above, and store the new epochs. We read and write the epochs in such a way that sched_clock() can easily (and locklessly) detect when an update is in progress, and repeat the loading of these constants when they're known not to be stable. The one caveat is that sched_clock() is not called in the middle of an update. We achieve that by disabling IRQs. Finally, if the clock rate is known at compile time, the counter to ns conversion factors can be specified, allowing sched_clock() to be tightly optimized. We ensure that these factors are correct by providing an initialization function which performs a run-time check. Acked-by: Peter Zijlstra <peterz@infradead.org> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Tested-by: Eric Miao <eric.y.miao@gmail.com> Tested-by: Olof Johansson <olof@lixom.net> Tested-by: Jamie Iles <jamie@jamieiles.com> Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>		2010-12-22 22:44:43 +00:00
..
hardware	ARM: pxa: fix the missing definition of IRQ_BOARD_END	2010-11-03 23:11:17 +08:00
mach	arm: remove machine_desc.io_pg_offst and .phys_io	2010-10-20 00:27:46 -04:00
a.out-core.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
a.out.h	headers_check fix: arm, a.out.h	2009-02-01 11:01:22 +05:30
asm-offsets.h	kbuild: move asm-offsets.h to include/generated	2009-12-12 13:08:14 +01:00
assembler.h	ARM: 6489/1: thumb2: fix incorrect optimisation in usracc	2010-11-21 22:05:58 +00:00
atomic.h	ARM: 6212/1: atomic ops: add memory constraints to inline asm	2010-07-09 11:29:35 +01:00
auxvec.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
bitops.h	ARM: boolean bit testing	2009-10-11 16:25:06 +01:00
bitsperlong.h	asm-generic: introduce asm/bitsperlong.h	2009-06-11 21:02:14 +02:00
bug.h	[ARM] 5211/2: fix a couple warnings from BUG() usage	2008-09-01 12:06:27 +01:00
bugs.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
byteorder.h	byteorder: make swab.h include asm/swab.h like a regular header	2009-01-14 19:56:50 -08:00
cache.h	dma-mapping: rename ARCH_KMALLOC_MINALIGN to ARCH_DMA_MINALIGN	2010-08-11 08:59:21 -07:00
cacheflush.h	Merge branches 'at91', 'dcache', 'ftrace', 'hwbpt', 'misc', 'mmci', 's3c', 'st-ux' and 'unwind' into devel	2010-10-18 22:34:25 +01:00
cachetype.h	ARM: 6385/1: setup: detect aliasing I-cache when D-cache is non-aliasing	2010-10-04 20:57:09 +01:00
checksum.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
clkdev.h	ARM: 6001/1: removing compilation warning comming from clkdev.h	2010-03-29 17:33:32 +01:00
cpu-multi32.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
cpu-single.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
cpu.h	ARM: 5872/1: ARM: include needed linux/cpu.h in asm/cpu.h	2010-01-10 13:03:52 +00:00
cputime.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
cputype.h	Merge branch 'devel' of git://git.kernel.org/pub/scm/linux/kernel/git/ycmiao/pxa-linux-2.6 into devel	2009-09-21 16:02:30 +01:00
current.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
delay.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
device.h	Driver Core: Add platform device arch data V3	2009-07-22 00:28:38 +02:00
div64.h	[ARM] 5320/1: fix assembly constraints in implementation of do_div()	2008-10-23 12:53:32 +01:00
dma-mapping.h	Revert "[ARM] pxa: remove now unnecessary dma_needs_bounce()"	2010-09-08 12:28:39 +01:00
dma.h	ARM: 5870/1: arch/arm: Fix build failure for defconfigs without CONFIG_ISA_DMA_API set	2010-01-10 00:08:03 +00:00
domain.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
ecard.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
elf.h	ARM: add a vma entry for the user accessible vector page	2010-10-01 22:35:19 -04:00
emergency-restart.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
entry-macro-vic2.S	ARM: Add common entry code for system with two VICs	2010-01-15 17:10:14 +09:00
errno.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
fb.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
fcntl.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
fiq.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
fixmap.h	[ARM] fixmap support	2009-03-15 21:01:20 -04:00
flat.h	flat: fix data sections alignment	2009-05-29 08:40:02 -07:00
floppy.h	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
fpstate.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
ftrace.h	ARM: 6319/1: ftrace: add Thumb-2 support to dynamic ftrace	2010-09-02 15:28:43 +01:00
futex.h	ARM: fix build error in arch/arm/kernel/process.c	2010-04-21 08:45:21 +01:00
glue.h	ARM: 5727/1: Pass IFSR register to do_PrefetchAbort()	2009-10-02 22:34:32 +01:00
gpio.h	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
hardirq.h	ARM: 6138/1: Add support for 10 hardirq bits	2010-05-20 23:51:07 +01:00
highmem.h	mm: stack based kmap_atomic()	2010-10-26 16:52:08 -07:00
hw_breakpoint.h	ARM: 6357/1: hw-breakpoint: add new ptrace requests for hw-breakpoint interaction	2010-09-08 10:05:00 +01:00
hw_irq.h	arm: Use ARCH_IRQ_INIT_FLAGS	2010-10-16 22:57:38 +02:00
hwcap.h	ARM: 6207/1: Replace CONFIG_HAS_TLS_REG with HWCAP_TLS and check for it on V6	2010-07-09 14:41:35 +01:00
ide.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
io.h	ARM: implement CONFIG_STRICT_DEVMEM by disabling access to RAM via /dev/mem	2010-10-01 22:31:34 -04:00
ioctl.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
ioctls.h	ioctl: Use asm-generic/ioctls.h on arm (enables termiox)	2010-10-22 10:19:59 -07:00
ipcbuf.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
irq_regs.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
irq.h	ARM: 6197/2: preliminary support for sparse IRQ	2010-07-09 14:41:33 +01:00
irqflags.h	Fix IRQ flag handling naming	2010-10-07 14:08:55 +01:00
Kbuild	archs: replace unifdef-y with header-y	2010-08-14 22:26:51 +02:00
kdebug.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
kexec.h	ARM: 6117/1: kdump: implement crash_setup_regs()	2010-07-09 15:00:51 +01:00
kgdb.h	kgdb,arm: fix register dump	2010-10-29 13:14:40 -05:00
kmap_types.h	kdb: core for kgdb back end (2 of 2)	2010-05-20 21:04:21 -05:00
kprobes.h	[ARM] 5206/1: remove kprobe_trap_handler() hack	2008-09-01 12:06:26 +01:00
leds.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
limits.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
linkage.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
local64.h	arch: Implement local64_t	2010-06-09 11:12:36 +02:00
local.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
localtimer.h	[ARM] smp: allow re-use of realview localtimer TWD support	2009-05-17 19:16:41 +01:00
locks.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
mach-types.h	arm: move mach-types to include/generated	2009-12-12 13:08:14 +01:00
mc146818rtc.h	[ARM] Convert asm/io.h to linux/io.h	2008-09-06 12:10:45 +01:00
memblock.h	ARM: fix memblock breakage	2010-10-27 21:41:39 +01:00
memory.h	Merge branch 'misc' into devel	2010-07-31 14:20:02 +01:00
mman.h	arm: add arch_mmap_check(), get rid of sys_arm_mremap()	2009-12-11 06:34:09 -05:00
mmu_context.h	ARM: add a vma entry for the user accessible vector page	2010-10-01 22:35:19 -04:00
mmu.h	ARM: 6490/1: MM: bugfix: initialize spinlock for init_mm.context	2010-11-23 22:46:12 +00:00
module.h	ARM: 6340/1: module - additional unwind tables for exit/devexit sections	2010-09-02 15:31:35 +01:00
msgbuf.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
mtd-xip.h	[ARM] move asm/xip.h's mach/hardware.h include to mach/xip.h	2008-12-14 13:22:51 +00:00
mutex.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
nwflash.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
outercache.h	arm: Disable outer (L2) cache in kexec	2010-10-26 11:39:56 +05:30
page-nommu.h	nommu: Remove the memory_start/end variables from ARM page-nommu.h	2009-07-24 12:35:01 +01:00
page.h	ARM: Pass VMA to copy_user_highpage() implementations	2009-10-05 15:17:45 +01:00
param.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
parport.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
pci.h	ARM: 6058/1: Add support for PCI domains	2010-04-22 21:38:11 +01:00
percpu.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
perf_event.h	irq_work: Add generic hardirq context callbacks	2010-10-18 19:58:50 +02:00
pgalloc.h	ARM: implement highpte	2009-08-17 20:02:06 +01:00
pgtable-hwdef.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
pgtable-nommu.h	ARM: 5988/1: pgprot_dmacoherent() for non-mmu builds	2010-03-13 10:48:22 +00:00
pgtable.h	ARM: improve compiler's ability to optimize page tables	2010-11-21 14:42:47 +00:00
pmu.h	ARM: 6064/1: pmu: register IRQs at runtime	2010-05-17 11:53:57 +01:00
poll.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
posix_types.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
proc-fns.h	ARM: Kill CONFIG_CPU_32	2009-12-18 16:07:53 +00:00
processor.h	ARM: 6357/1: hw-breakpoint: add new ptrace requests for hw-breakpoint interaction	2010-09-08 10:05:00 +01:00
procinfo.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
ptrace.h	ARM: 6357/1: hw-breakpoint: add new ptrace requests for hw-breakpoint interaction	2010-09-08 10:05:00 +01:00
resource.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
scatterlist.h	asm-generic: remove ARCH_HAS_SG_CHAIN in scatterlist.h	2010-05-27 09:12:54 -07:00
sched_clock.h	ARM: sched_clock: provide common infrastructure for sched_clock()	2010-12-22 22:44:43 +00:00
seccomp.h	ARM: SECCOMP support	2010-10-01 22:32:18 -04:00
sections.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
segment.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
sembuf.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
serial.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
setup.h	ARM: Remove DISCONTIGMEM support	2010-07-16 10:57:35 +01:00
shmbuf.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
shmparam.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
sigcontext.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
siginfo.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
signal.h	asm-generic: rename termios.h, signal.h and mman.h	2009-06-11 21:01:52 +02:00
sizes.h	[ARM] Kirkwood: create a mapping for the Security Accelerator SRAM	2009-06-08 13:05:02 -04:00
smp_mpidr.h	ARM: Allow SMP kernels to boot on UP systems	2010-10-04 20:23:36 +01:00
smp_plat.h	Merge branches 'at91', 'dcache', 'ftrace', 'hwbpt', 'misc', 'mmci', 's3c', 'st-ux' and 'unwind' into devel	2010-10-18 22:34:25 +01:00
smp_scu.h	[ARM] smp: separate SCU support code from realview	2009-05-17 19:00:37 +01:00
smp_twd.h	ARM: 6125/1: ARM TWD: move TWD registers to common header	2010-05-12 11:18:13 +01:00
smp.h	ARM: rename mach_cpu_disable() to platform_cpu_disable()	2010-05-15 15:03:51 +01:00
socket.h	net: Generalize socket rx gap / receive queue overflow cmsg	2009-10-12 13:26:31 -07:00
sockios.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
sparsemem.h	[ARM] mm: enable sparsemem on clps7500 and RiscPC	2008-10-01 17:24:04 +01:00
spinlock_types.h	locking: Convert raw_rwlock to arch_rwlock	2009-12-14 23:55:32 +01:00
spinlock.h	ARM: 5897/1: spinlock: don't use deprecated barriers on ARMv7	2010-02-15 21:39:50 +00:00
stackprotector.h	ARM: initial stack protector (-fstack-protector) support	2010-06-14 21:31:00 -04:00
stacktrace.h	[ARM] 5382/1: unwind: Reorganise the stacktrace support	2009-02-12 13:21:17 +00:00
stat.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
statfs.h	ARM: Use <asm-generic/statfs.h>	2008-09-04 09:46:11 +01:00
string.h	[ARM] remove memzero()	2008-11-27 12:37:59 +00:00
swab.h	ARM: 5772/1: Use REV and REV16 for byte swapping on ARMv6+	2009-10-25 15:59:53 +00:00
system.h	ARM: place C irq handlers in IRQ_ENTRY for ftrace	2010-11-19 21:43:26 +05:30
tcm.h	ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3	2009-09-15 22:11:05 +01:00
termbits.h	tty: Add EXTPROC support for LINEMODE	2010-08-10 13:47:39 -07:00
termios.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
therm.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
thread_info.h	ARM: SECCOMP support	2010-10-01 22:32:18 -04:00
thread_notify.h	ARM: Convert VFP/Crunch/XscaleCP thread_release() to exit_thread()	2009-12-18 14:53:41 +00:00
timex.h	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
tlb.h	mm: Pass virtual address to [__]p{te,ud,md}_free_tlb()	2009-07-27 12:10:38 -07:00
tlbflush.h	Merge branches 'at91', 'dcache', 'ftrace', 'hwbpt', 'misc', 'mmci', 's3c', 'st-ux' and 'unwind' into devel	2010-10-18 22:34:25 +01:00
tls.h	ARM: 6207/1: Replace CONFIG_HAS_TLS_REG with HWCAP_TLS and check for it on V6	2010-07-09 14:41:35 +01:00
topology.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
traps.h	ARM: place C irq handlers in IRQ_ENTRY for ftrace	2010-11-19 21:43:26 +05:30
types.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
uaccess.h	ARM: fix build error in arch/arm/kernel/process.c	2010-04-21 08:45:21 +01:00
ucontext.h	ARM: 6051/1: VFP: preserve the HW context when calling signal handlers	2010-04-14 11:11:30 +01:00
unaligned.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
unified.h	Fix "W" macro in arch/arm/include/asm/unified.h	2009-09-18 23:30:11 +01:00
unistd.h	ARM: 6343/1: wire up fanotify and prlimit64 syscalls on ARM	2010-09-01 10:06:08 +01:00
unwind.h	[ARM] 5383/2: unwind: Add core support for ARM stack unwinding	2009-02-19 11:26:24 +00:00
user.h	ARM: 6051/1: VFP: preserve the HW context when calling signal handlers	2010-04-14 11:11:30 +01:00
vfp.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00
vfpmacros.h	ARM: 6203/1: Make VFPv3 usable on ARMv6	2010-07-09 14:41:34 +01:00
vga.h	[ARM] Convert asm/io.h to linux/io.h	2008-09-06 12:10:45 +01:00
xor.h	[ARM] move include/asm-arm to arch/arm/include/asm	2008-08-02 21:32:35 +01:00