linux-stable-rt/arch/arm/plat-omap
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
..
include/mach ARM: OMAP: Fix compile error if pm.h is included 2009-03-04 10:07:40 -08:00
Kconfig
Makefile
clock.c
common.c ARM: OMAP: sched_clock() corrected 2009-03-04 10:07:41 -08:00
cpu-omap.c
debug-devices.c
debug-leds.c
devices.c ARM: OMAP: Fix hsmmc init, v2 2009-01-29 08:57:16 -08:00
dma.c ARM: OMAP: DMA: Fix uninitialized channel flags 2009-01-29 08:57:12 -08:00
dmtimer.c
fb.c
gpio.c ARM: OMAP: Fix gpio.c compile on 15xx with CONFIG_DEBUGFS 2009-01-15 13:09:53 +02:00
i2c.c [ARM] fix AT91, davinci, h720x, ks8695, msm, mx2, mx3, netx, omap1, omap2, pxa, s3c 2009-01-08 16:29:42 +00:00
io.c
mailbox.c
mailbox.h
mcbsp.c ARM: OMAP: Fix McBSP spin_lock deadlock 2009-01-29 08:57:12 -08:00
mux.c
ocpi.c
sram.c
usb.c [ARM] omap: usb: thou shalt not provide empty release functions 2009-01-24 17:00:45 +00:00