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Russell King b9d82c9f88 ARM: sched_clock: make minsec argument to clocks_calc_mult_shift() zero 
The purpose of the minsec argument is to prevent 64-bit math overflow
when the number of cycles is multiplied up.  However, the multipler
is 32-bit, and in the sched_clock() case, the cycle counter is up to
32-bit as well.  So the math can never overflow.

With a value of 60, and clock rates greater than 71MHz, the calculated
multiplier is unnecessarily reduced in value, which reduces accuracy by
maybe 70ppt.  It's almost not worth bothering with as the oscillator
driving the counter won't be any more than 1ppm - unless you're using
a rubidium lamp or caesium fountain frequency standard.

So, set the minsec argument to zero.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-03-11 11:37:02 +08:00
..
.gitignore [ARM] 5194/1: update .gitignore 2008-08-12 19:54:09 +01:00
armksyms.c [ARM] support tracing when using newer compilers 2009-08-13 20:34:36 +02:00
arthur.c [ARM] arm/kernel/arthur.c: add MODULE_LICENSE 2008-05-17 22:55:16 +01:00
asm-offsets.c arm: use kbuild.h instead of macros in asm-offsets.c 2008-04-29 08:06:29 -07:00
atags.c clean up atags exporting code 2008-05-30 10:33:49 +02:00
atags.h [ARM] 4736/1: Export atags to userspace and allow kexec to use customised atags 2008-02-04 13:21:03 +00:00
bios32.c PCI: arm: use generic INTx swizzle from PCI core 2009-01-07 11:13:13 -08:00
calls.S untangle the do_mremap() mess 2010-01-18 10:19:11 -08:00
compat.c
compat.h
crunch-bits.S [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach 2008-08-07 09:55:48 +01:00
crunch.c [ARM] 5577/2: ep93xx: syscon locked register functions 2009-07-09 16:10:51 +01:00
debug.S [ARM] Allow ICEDCC to work with CPU_V7 as well as CPU_V6. 2010-02-03 20:48:12 -08:00
dma-isa.c [ARM] dma: make DMA_MODE_xxx reflect ISA DMA settings 2009-01-02 12:18:53 +00:00
dma.c add dma irq mode 2010-06-21 13:35:20 +08:00
ecard.c arm: struct device - replace bus_id with dev_name(), dev_set_name() 2009-01-06 10:44:43 -08:00
ecard.h [ARM] rpc: ecard: remove deprecated ecard_address() and relatives 2008-07-03 14:25:58 +01:00
elf.c [ARM] disable NX support for OABI-supporting kernels 2009-05-23 11:36:20 +01:00
entry-armv.S HACK stay compatible with the emulated TLS register HACK 2010-02-08 15:36:09 -08:00
entry-common.S HSL: dbg:add some debug function 2011-01-27 16:17:35 +08:00
entry-header.S ARM: 5757/1: Thumb-2: Correct "mov.w pc, lr" instruction which is unpredictable 2009-10-14 10:33:05 +01:00
fiq.c [ARM] 5421/1: ftrace: fix crash due to tracing of __naked functions 2009-03-12 21:33:03 +00:00
ftrace.c small doc fix: ftrace_dyn_arch_init is called by ftrace_init 2008-12-12 11:15:45 +01:00
head-common.S ARM: 5784/1: fix early boot machine ID mismatch error display 2009-11-08 11:58:54 +00:00
head-nommu.S nommu: Do not override the CP15 control reg value returned from initfunc 2009-07-24 12:34:59 +01:00
head.S Thumb-2: Implementation of the unified start-up and exceptions code 2009-07-24 12:32:54 +01:00
init_task.c Use new __init_task_data macro in arch init_task.c files. 2009-09-21 06:27:08 +02:00
io.c [ARM] Convert asm/io.h to linux/io.h 2008-09-06 12:10:45 +01:00
irq.c ARM: Show FIQ in /proc/interrupts on CONFIG_FIQ 2009-08-17 00:00:41 +01:00
isa.c [ARM] arch/arm/kernel/isa.c: missing definition of register_isa_ports 2009-01-08 15:53:08 +00:00
iwmmxt.S
kgdb.c kgdb, x86, arm, mips, powerpc: ignore user space single stepping 2008-09-26 10:36:41 -05:00
kprobes-decode.c ARM: 6226/1: fix kprobe bug in ldr instruction emulation 2010-08-02 10:21:02 -07:00
kprobes.c ARM: 5715/1: Make kprobes unregistration SMP safe 2009-09-21 16:39:12 +01:00
machine_kexec.c [ARM] Storage class should be before const qualifier 2009-02-10 09:59:19 +00:00
Makefile ARM: sched_clock: provide common infrastructure for sched_clock() 2011-03-11 11:34:57 +08:00
module.c Thumb-2: Add support for loadable modules 2009-07-24 12:32:59 +01:00
process.c reboot function 2010-06-21 13:35:26 +08:00
ptrace.c nommu: ptrace support 2009-07-24 12:34:58 +01:00
ptrace.h
relocate_kernel.S [ARM] 4736/1: Export atags to userspace and allow kexec to use customised atags 2008-02-04 13:21:03 +00:00
return_address.c [ARM] 5613/1: implement CALLER_ADDRESSx 2009-07-21 17:21:28 +01:00
sched_clock.c ARM: sched_clock: make minsec argument to clocks_calc_mult_shift() zero 2011-03-11 11:37:02 +08:00
setup.c ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3 2009-09-15 22:11:05 +01:00
signal.c [ARM] Add code to prevent system calls from being restarted muliple times before returning from the kernel. 2010-02-03 20:48:11 -08:00
signal.h ARM: Fix signal restart issues with NX and OABI compat 2009-10-25 15:39:37 +00:00
smp.c ARM: Fix __cpuexit section mismatch warnings 2009-09-28 18:06:21 +01:00
smp_scu.c Check whether the SCU was already initialised 2009-11-05 10:10:36 +00:00
smp_twd.c ARM: Fix __cpuexit section mismatch warnings 2009-09-28 18:06:21 +01:00
stacktrace.c [ARM] 5613/1: implement CALLER_ADDRESSx 2009-07-21 17:21:28 +01:00
sys_arm.c untangle the do_mremap() mess 2010-01-18 10:19:11 -08:00
sys_oabi-compat.c Separate out common fstatat code into vfs_fstatat 2009-04-20 23:02:51 -04:00
tcm.c tcm: use dtcm instead of sram. dtcm is ok now. 2010-08-30 11:38:56 +08:00
tcm.h ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3 2009-09-15 22:11:05 +01:00
thumbee.c Fix the teehbr_read function prototype 2008-11-10 14:14:11 +00:00
time.c ARM: sched_clock: allow init_sched_clock() to be called early 2011-03-11 11:36:09 +08:00
traps.c [ARM] Do not call flush_cache_user_range with mmap_sem held 2010-05-04 18:02:20 -07:00
unwind.c ARM: 5776/1: Check compiler version and EABI support when adding ARM unwind support. 2009-11-02 16:59:45 +00:00
vmlinux.lds.S rk29: add sram support 2011-01-25 20:30:13 +08:00
xscale-cp0.c [ARM] Convert asm/io.h to linux/io.h 2008-09-06 12:10:45 +01:00