1
linux/arch/powerpc/kernel
Paul Mackerras 0a45d4491d powerpc: Fix problem with time going backwards
The recent changes to keep gettimeofday in sync with xtime had the side
effect that it was occasionally possible for the time reported by
gettimeofday to go back by a microsecond.  There were two reasons:
(1) when we recalculated the offsets used by gettimeofday every 2^31
timebase ticks, we lost an accumulated fractional microsecond, and
(2) because the update is done some time after the notional start of
jiffy, if ntp is slowing the clock, it is possible to see time go backwards
when the timebase factor gets reduced.

This fixes it by (a) slowing the gettimeofday clock by about 1us in
2^31 timebase ticks (a factor of less than 1 in 3.7 million), and (b)
adjusting the timebase offsets in the rare case that the gettimeofday
result could possibly go backwards (i.e. when ntp is slowing the clock
and the timer interrupt is late).  In this case the adjustment will
reduce to zero eventually because of (a).

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-16 16:54:55 +11:00
..
vdso32 [PATCH] powerpc: Add some missing .gitignore's 2006-01-11 15:35:35 +11:00
vdso64 [PATCH] powerpc: vdso 64bits gettimeofday bug 2006-02-28 16:25:54 +11:00
align.c [PATCH] powerpc: merge align.c 2005-11-18 14:39:23 +11:00
asm-offsets.c powerpc: Fix various syscall/signal/swapcontext bugs 2006-03-08 13:24:22 +11:00
binfmt_elf32.c ppc64: merge binfmt_elf32.c 2005-10-13 13:40:54 +10:00
btext.c [PATCH] powerpc: Remove device_node addrs/n_addr 2006-01-09 14:53:55 +11:00
cpu_setup_power4.S [PATCH] powerpc: Cleanup LOADADDR etc. asm macros 2006-01-13 21:16:23 +11:00
cputable.c [PATCH] powerpc: Expose SMT and L1 icache snoop userland features 2006-03-03 22:00:23 +11:00
crash_dump.c powerpc: Fix compile error when CONFIG_PROC_VMCORE is not defined 2006-01-11 15:30:07 +11:00
crash.c [PATCH] powerpc: Trivial fix to set the proper timeout value for kdump 2006-02-24 11:36:21 +11:00
dma_64.c [PATCH] powerpc: IBMEBUS bus support 2006-01-09 14:49:06 +11:00
entry_32.S powerpc: Fix various syscall/signal/swapcontext bugs 2006-03-08 13:24:22 +11:00
entry_64.S powerpc: Fix various syscall/signal/swapcontext bugs 2006-03-08 13:24:22 +11:00
firmware.c [PATCH] powerpc: Move various ppc64 files with no ppc32 equivalent to powerpc 2005-11-10 11:24:04 +11:00
fpu.S powerpc/64: Fix bug in setting floating-point exception mode 2006-02-07 13:55:30 +11:00
head_4xx.S powerpc: Rename asm offset TRAP to _TRAP for 32-bit 2005-10-28 22:45:25 +10:00
head_8xx.S powerpc: Rename asm offset TRAP to _TRAP for 32-bit 2005-10-28 22:45:25 +10:00
head_32.S [PATCH] powerpc: fix altivec_unavailable_exception Oopses 2006-02-24 11:36:23 +11:00
head_44x.S [PATCH] powerpc: replace use of _GLOBAL with .globl 2005-10-17 21:43:12 +10:00
head_64.S ppc64: make sure to align stack pointer to 16 bytes at boot 2006-03-04 15:00:45 -08:00
head_fsl_booke.S [PATCH] Update email address for Kumar 2005-11-13 18:14:10 -08:00
ibmebus.c [PATCH] powerpc: IBMEBUS bus support 2006-01-09 14:49:06 +11:00
idle_6xx.S powerpc: Use reg.h instead of processor.h when we just want reg names 2005-10-10 22:20:10 +10:00
idle_64.c powerpc: Move remaining .c files from arch/ppc64 to arch/powerpc 2005-11-18 15:43:34 +11:00
idle_power4.S [PATCH] powerpc: Cleanup LOADADDR etc. asm macros 2006-01-13 21:16:23 +11:00
init_task.c powerpc: make process.c suitable for both 32-bit and 64-bit 2005-10-10 22:29:05 +10:00
iomap.c powerpc: Move most remaining ppc64 files over to arch/powerpc 2005-11-14 17:30:17 +11:00
iommu.c [PATCH] powerpc: IOMMU SG paranoia 2006-02-07 21:28:38 +11:00
irq.c [PATCH] powerpc: Remove lppaca structure from the PACA 2006-01-13 21:17:39 +11:00
kprobes.c [PATCH] kprobes: fix race in recovery of reentrant probe 2006-01-11 18:42:12 -08:00
legacy_serial.c [PATCH] CONFIG_ISA does not make sense for CONFIG_PPC_PSERIES 2006-02-01 08:53:08 -08:00
lparcfg.c [PATCH] powerpc: Fix OOPS in lparcfg on G5 2006-02-20 10:44:34 +11:00
lparmap.c [PATCH] powerpc: Fix iSeries bug in VMALLOCBASE/VMALLOC_START consolidation 2006-01-09 15:06:06 +11:00
machine_kexec_32.c [PATCH] powerpc: Merge kexec 2006-01-09 14:48:52 +11:00
machine_kexec_64.c [PATCH] powerpc: Only calculate htab_size in one place for kexec 2006-02-24 11:36:18 +11:00
machine_kexec.c [PATCH] powerpc: remove remaining crash_notes variable from machine_kexec.c 2006-01-11 14:48:02 +11:00
Makefile ppc: Use the system call table from arch/powerpc/kernel/systbl.S 2006-02-10 16:02:20 +11:00
misc_32.S [PATCH] powerpc: Cleanup LOADADDR etc. asm macros 2006-01-13 21:16:23 +11:00
misc_64.S [PATCH] powerpc: Cleanup LOADADDR etc. asm macros 2006-01-13 21:16:23 +11:00
module_64.c powerpc: Move most remaining ppc64 files over to arch/powerpc 2005-11-14 17:30:17 +11:00
nvram_64.c [PATCH] powerpc: fix large nvram access 2006-01-09 14:53:31 +11:00
of_device.c [PATCH] Add of_platform_bus_type probe and remove methods 2006-01-13 11:26:06 -08:00
paca.c [PATCH] powerpc: Remove lppaca structure from the PACA 2006-01-13 21:17:39 +11:00
pci_32.c powerpc/32: Restore previous version of 32-bit PCI code 2006-01-15 22:05:47 +11:00
pci_64.c [PATCH] powerpc: small pci cleanups 2006-01-12 20:09:30 +11:00
pci_direct_iommu.c powerpc: Move most remaining ppc64 files over to arch/powerpc 2005-11-14 17:30:17 +11:00
pci_dn.c powerpc: Move most remaining ppc64 files over to arch/powerpc 2005-11-14 17:30:17 +11:00
pci_iommu.c powerpc: Move most remaining ppc64 files over to arch/powerpc 2005-11-14 17:30:17 +11:00
pmc.c [PATCH] powerpc: G4+ oprofile support 2006-01-09 15:06:03 +11:00
ppc32.h powerpc: move include/asm-ppc64/ppc32.h to arch/powerpc/kernel 2005-11-03 16:03:28 +11:00
ppc_ksyms.c [PATCH] powerpc: remove duplicate exports 2006-02-20 10:44:31 +11:00
proc_ppc64.c [PATCH] powerpc: Merge vdso's and add vdso support to 32 bits kernel 2005-11-11 22:25:39 +11:00
process.c [PATCH] powerpc: Fix runlatch performance issues 2006-02-24 11:36:31 +11:00
prom_init.c [PATCH] powerpc: incorrect rmo_top handling in prom_init 2006-03-03 22:01:05 +11:00
prom_parse.c [PATCH] powerpc: add refcounting to setup_peg2 and of_get_pci_address 2006-02-07 21:32:45 +11:00
prom.c [PATCH] powerpc: Fix mem= cmdline handling on arch/powerpc for !MULTIPLATFORM 2006-02-24 14:34:50 -08:00
ptrace32.c [PATCH] use ptrace_get_task_struct in various places 2006-01-08 20:13:51 -08:00
ptrace-common.h [PATCH] powerpc: task_thread_info() 2006-01-12 09:08:57 -08:00
ptrace.c powerpc: Fix various syscall/signal/swapcontext bugs 2006-03-08 13:24:22 +11:00
rtas_flash.c [PATCH] Don't check pointer for NULL before passing it to kfree [arch/powerpc/kernel/rtas_flash.c] 2006-02-07 21:51:53 +11:00
rtas_pci.c [PATCH] powerpc: Save device BARs much earlier in the boot sequence 2006-01-10 15:30:39 +11:00
rtas-proc.c [PATCH] powerpc: Merge vdso's and add vdso support to 32 bits kernel 2005-11-11 22:25:39 +11:00
rtas-rtc.c powerpc: time-of-day fixes for 32-bit CHRP systems 2005-11-18 15:52:38 +11:00
rtas.c [PATCH] powerpc: remove useless call to touch_softlockup_watchdog 2006-02-07 21:32:44 +11:00
semaphore.c powerpc: Merge enough to start building in arch/powerpc. 2005-09-26 16:04:21 +10:00
setup_32.c powerpc: Introduce a new config symbol to control 16550 early debug code 2006-01-10 16:19:05 +11:00
setup_64.c [PATCH] powerpc: Don't start secondary CPUs in a UP && KEXEC kernel 2006-02-20 12:03:34 +11:00
setup-common.c [PATCH] powerpc: Allow for ppc_md restart, power_off, and halt to be NULL 2006-01-14 11:12:23 +11:00
setup.h powerpc: create kernel/setup.h 2005-11-09 11:35:26 +11:00
signal_32.c powerpc: Fix various syscall/signal/swapcontext bugs 2006-03-08 13:24:22 +11:00
signal_64.c powerpc: Fix various syscall/signal/swapcontext bugs 2006-03-08 13:24:22 +11:00
smp-tbsync.c powerpc: Merge smp-tbsync.c (the generic timebase sync routine) 2005-11-04 13:28:58 +11:00
smp.c [PATCH] powerpc: avoid timer interrupt replay effect when onlining cpu 2006-02-07 21:51:54 +11:00
sys_ppc32.c powerpc: Keep xtime and gettimeofday in sync 2006-02-20 10:38:56 +11:00
syscalls.c [PATCH] ppc64: fix time syscall 2006-01-09 15:47:13 +11:00
sysfs.c [PATCH] powerpc: Merge vdso's and add vdso support to 32 bits kernel 2005-11-11 22:25:39 +11:00
systbl.S powerpc: Fix various syscall/signal/swapcontext bugs 2006-03-08 13:24:22 +11:00
time.c powerpc: Fix problem with time going backwards 2006-03-16 16:54:55 +11:00
traps.c powerpc: Fix might-sleep warning in program check exception handler 2006-03-03 17:11:40 +11:00
udbg_16550.c [PATCH] powerpc: fix compile warning in udbg_init_maple_realmode 2006-02-07 21:51:52 +11:00
udbg.c [PATCH] powerpc: Make early debugging configurable via Kconfig 2006-01-11 14:48:26 +11:00
vdso.c [PATCH] Add mm->task_size and fix powerpc vdso 2006-02-28 20:53:44 -08:00
vecemu.c [PATCH] powerpc: Move arch/ppc*/kernel/vecemu.c to arch/powerpc 2005-09-21 19:21:07 +10:00
vector.S powerpc: Use reg.h instead of processor.h when we just want reg names 2005-10-10 22:20:10 +10:00
vio.c [PATCH] Add vio_bus_type probe and remove methods 2006-01-13 11:26:07 -08:00
vmlinux.lds.S powerpc: Fix vmlinux.lds.S for 32-bit 2005-11-05 10:36:59 +11:00