linux-stable-rt/arch
Aaro Koskinen 80ea3bac3a ARM: OMAP: sched_clock() corrected
After my OMAP3 board has been running for a while, I'm seeing weird
latency traces like this:

      sh-1574    0d.h2  153us : do_timer (tick_do_update_jiffies64)
      sh-1574    0d.h2  153us : update_wall_time (do_timer)
      sh-1574    0d.h2  153us!: omap_32k_read (update_wall_time)
      sh-1574    0d.h2 1883us : update_xtime_cache (update_wall_time)
      sh-1574    0d.h2 1883us : clocksource_get_next (update_wall_time)
      sh-1574    0d.h2 1883us+: _spin_lock_irqsave (clocksource_get_next)

and after a while:

      sh-17818   0d.h3  153us : do_timer (tick_do_update_jiffies64)
      sh-17818   0d.h3  153us : update_wall_time (do_timer)
      sh-17818   0d.h3  153us!: omap_32k_read (update_wall_time)
      sh-17818   0d.h3 1915us : update_xtime_cache (update_wall_time)
      sh-17818   0d.h3 1915us+: clocksource_get_next (update_wall_time)
      sh-17818   0d.h3 1945us : _spin_lock_irqsave (clocksource_get_next)

Turns out that sched_clock() is using cyc2ns(), which returns NTP
adjusted time. The sched_clock() frequency should not be adjusted. The
patch deletes omap_32k_ticks_to_nsecs() and rewrites sched_clock()
to do the conversion using the constant multiplier.

Signed-off-by: Aaro Koskinen <Aaro.Koskinen@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2009-03-04 10:07:41 -08:00
..
alpha
arm ARM: OMAP: sched_clock() corrected 2009-03-04 10:07:41 -08:00
avr32
blackfin
cris
frv
h8300
ia64 [IA64] Don't go beyond iosapic_intr_info's arraysize 2009-02-25 11:50:53 -08:00
m32r
m68k m68k: atari - Rename "mfp" to "st_mfp" 2009-02-22 09:23:02 -08:00
m68knommu
mips x86-64: seccomp: fix 32/64 syscall hole 2009-03-02 15:41:30 -08:00
mn10300 mn10300: fix typo && -> || in arch/mn10300/unit-asb2305/pci.c 2009-02-20 17:57:48 -08:00
parisc
powerpc x86-64: seccomp: fix 32/64 syscall hole 2009-03-02 15:41:30 -08:00
s390 Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2009-03-03 17:05:08 -08:00
sh sh: ap325rxa: Revert ov772x support. 2009-02-27 15:41:14 +09:00
sparc x86-64: seccomp: fix 32/64 syscall hole 2009-03-02 15:41:30 -08:00
um uml: fix vde network backend in user mode linux 2009-02-20 17:57:48 -08:00
x86 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-03-03 14:32:55 -08:00
xtensa
.gitignore
Kconfig