linux-stable.git/include/linux/timex.h, branch linux-2.6.25.y

time: remove obsolete CLOCK_TICK_ADJUST

2008-03-09T07:42:57+00:00

The first version of the ntp_interval/tick_length inconsistent usage patch was
recently merged as bbe4d18ac2e058c56adb0cd71f49d9ed3216a405

http://git.kernel.org/gitweb.cgi?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=bbe4d18ac2e058c56adb0cd71f49d9ed3216a405

While the fix did greatly improve the situation, it was correctly pointed out
by Roman that it does have a small bug: If the users change clocksources after
the system has been running and NTP has made corrections, the correctoins made
against the old clocksource will be applied against the new clocksource,
causing error.

The second attempt, which corrects the issue in the NTP_INTERVAL_LENGTH
definition has also made it up-stream as commit
e13a2e61dd5152f5499d2003470acf9c838eab84

http://git.kernel.org/gitweb.cgi?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=e13a2e61dd5152f5499d2003470acf9c838eab84

Roman has correctly pointed out that CLOCK_TICK_ADJUST is calculated
based on the PIT's frequency, and isn't really relevant to non-PIT
driven clocksources (that is, clocksources other then jiffies and pit).

This patch reverts both of those changes, and simply removes
CLOCK_TICK_ADJUST.

This does remove the granularity error correction for users of PIT and Jiffies
clocksource users, but the granularity error but for the majority of users, it
should be within the 500ppm range NTP can accommodate for.

For systems that have granularity errors greater then 500ppm, the
"ntp_tick_adj=" boot option can be used to compensate.

[johnstul@us.ibm.com: provided changelog]
[mattilinnanvuori@yahoo.com: maek ntp_tick_adj static]
Signed-off-by: Roman Zippel 
Acked-by: john stultz 
Signed-off-by: Matti Linnanvuori 
Signed-off-by: Andrew Morton 
Cc: mingo@elte.hu
Signed-off-by: Thomas Gleixner

ntp: correct inconsistent interval/tick_length usage

2008-02-10T09:48:03+00:00

clocksource initialization and error accumulation.  This corrects a 280ppm
drift seen on some systems using acpi_pm, and affects other clocksources as
well (likely to a lesser degree).

Signed-off-by: John Stultz 
Cc: Roman Zippel 
Cc: Steven Rostedt 
Signed-off-by: Andrew Morton 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

read_current_timer() cleanups

2008-02-06T18:41:02+00:00

- All implementations can be __devinit

- The function prototypes were in asm/timex.h but they all must be the same,
  so create a single declaration in linux/timex.h.

- uninline the sparc64 version to match the other architectures

- Don't bother #defining ARCH_HAS_READ_CURRENT_TIMER to a particular value.

[ezk@cs.sunysb.edu: fix build]
Cc: "David S. Miller" 
Cc: Haavard Skinnemoen 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

time: add ADJ_OFFSET_SS_READ

2007-11-26T19:42:19+00:00

Michael Kerrisk reported that a long standing bug in the adjtimex()
system call causes glibc's adjtime(3) function to deliver the wrong
results if 'delta' is NULL.

add the ADJ_OFFSET_SS_READ API detail, which will be used by glibc
to fix this API compatibility bug.

Also see: http://bugzilla.kernel.org/show_bug.cgi?id=6761

[ mingo@elte.hu: added patch description and made it backwards compatible ]

NOTE: the new flag is defined 0xa001 so that it returns -EINVAL on
older kernels - this way glibc can use it safely. Suggested by Ulrich
Drepper.

Acked-by: Ulrich Drepper 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

[IA64] remove time interpolator

2007-07-20T18:23:02+00:00

Remove time_interpolator code (This is generic code, but
only user was ia64.  It has been superseded by the
CONFIG_GENERIC_TIME code).

Signed-off-by: Bob Picco 
Signed-off-by: John Stultz 
Signed-off-by: Peter Keilty 
Signed-off-by: Tony Luck

[PATCH] HZ free ntp

2007-02-16T16:13:56+00:00

Distangle the NTP update from HZ.  This is necessary for dynamic tick enabled
kernels.

Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: john stultz 
Cc: Roman Zippel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] use cycle_t instead of u64 in struct time_interpolator

2007-02-11T18:51:31+00:00

The 32bit and 64bit PARISC Linux kernels suffers from the problem, that the
gettimeofday() call sometimes returns non-monotonic times.

The easiest way to fix this, is to drop the PARISC-specific implementation
and switch over to the generic TIME_INTERPOLATION framework.

But in order to make it even compile on 32bit PARISC, the patch below which
touches the generic Linux code, is mandatory.

More information and the full patch with the parisc-specific changes is included in this thread: http://lists.parisc-linux.org/pipermail/parisc-linux/2006-December/031003.html

As far as I could see, this patch does not change anything for the existing
architectures which use this framework (IA64 and SPARC64), since "cycles_t"
is defined there as unsigned 64bit-integer anyway (which then makes this
patch a no-change for them).

Signed-off-by: Helge Deller 
Cc: 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] provide tickadj define

2006-10-06T15:53:40+00:00

Provide a tickadj compatibility define for archs still using it.

Signed-off-by: Roman Zippel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] kernel/time/ntp.c: possible cleanups

2006-10-01T07:39:27+00:00

This patch contains the following possible cleanups:
- make the following needlessly global function static:
  - ntp_update_frequency()
- make the following needlessly global variables static:
  - time_state
  - time_offset
  - time_constant
  - time_reftime
- remove the following read-only global variable:
  - time_precision

Signed-off-by: Adrian Bunk 
Cc: Roman Zippel 
Cc: john stultz 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] ntp: cleanup defines and comments

2006-10-01T07:39:27+00:00

Remove a few unused defines and remove obsolete information from comments.

Signed-off-by: Roman Zippel 
Cc: john stultz 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds