linux/kernel/time, branch v2.6.30

clockevents: prevent endless loop in tick_handle_periodic()

2009-05-02T08:22:27Z

tick_handle_periodic() can lock up hard when a one shot clock event device is used in combination with jiffies clocksource. Avoid an endless loop issue by requiring that a highres valid clocksource be installed before we call tick_periodic() in a loop when using ONESHOT mode. The result is we will only increment jiffies once per interrupt until a continuous hardware clocksource is available. Without this, we can run into a endless loop, where each cycle through the loop, jiffies is updated which increments time by tick_period or more (due to clock steering), which can cause the event programming to think the next event was before the newly incremented time and fail causing tick_periodic() to be called again and the whole process loops forever. [ Impact: prevent hard lock up ] Signed-off-by: John Stultz Signed-off-by: Andrew Morton Signed-off-by: Thomas Gleixner Cc: stable@kernel.org

clocksource: add enable() and disable() callbacks

2009-04-21T20:41:47Z

Add enable() and disable() callbacks for clocksources. This allows us to put unused clocksources in power save mode. The functions clocksource_enable() and clocksource_disable() wrap the callbacks and are inserted in the timekeeping code to enable before use and disable after switching to a new clocksource. Signed-off-by: Magnus Damm Acked-by: John Stultz Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

clocksource: pass clocksource to read() callback

2009-04-21T20:41:47Z

Pass clocksource pointer to the read() callback for clocksources. This allows us to share the callback between multiple instances. [hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods] [akpm@linux-foundation.org: cleanup] Signed-off-by: Magnus Damm Acked-by: John Stultz Cc: Thomas Gleixner Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-03-26T23:05:42Z

* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (26 commits) posix timers: fix RLIMIT_CPU && fork() time: ntp: fix bug in ntp_update_offset() & do_adjtimex(), fix time: ntp: clean up second_overflow() time: ntp: simplify ntp_tick_adj calculations time: ntp: make 64-bit constants more robust time: ntp: refactor do_adjtimex() some more time: ntp: refactor do_adjtimex() time: ntp: fix bug in ntp_update_offset() & do_adjtimex() time: ntp: micro-optimize ntp_update_offset() time: ntp: simplify ntp_update_offset_fll() time: ntp: refactor and clean up ntp_update_offset() time: ntp: refactor up ntp_update_frequency() time: ntp: clean up ntp_update_frequency() time: ntp: simplify the MAX_TICKADJ_SCALED definition time: ntp: simplify the second_overflow() code flow time: ntp: clean up kernel/time/ntp.c x86: hpet: stop HPET_COUNTER when programming periodic mode x86: hpet: provide separate functions to stop and start the counter x86: hpet: print HPET registers during setup (if hpet=verbose is used) time: apply NTP frequency/tick changes immediately ...

Merge branches 'timers/new-apis', 'timers/ntp' and 'timers/urgent' into timers/core

2009-03-26T14:45:52Z

time: ntp: fix bug in ntp_update_offset() & do_adjtimex(), fix

2009-02-26T18:39:47Z

The time_status conditional was accidentally placed right after we clear the checked time_status bits, which causes us to take the conditional every time through. This fixes it by moving the conditional to before we clear the time_status bits. Signed-off-by: John Stultz Cc: Clark Williams Signed-off-by: Ingo Molnar

time: ntp: clean up second_overflow()

2009-02-25T17:38:17Z

Impact: cleanup, no functionality changed The 'time_adj' local variable is named in a very confusing way because it almost shadows the 'time_adjust' global variable - which is used in this same function. Rename it to 'delta' - to make them stand apart more clearly. kernel/time/ntp.o: text data bss dec hex filename 2545 114 144 2803 af3 ntp.o.before 2545 114 144 2803 af3 ntp.o.after md5: 1bf0b3be564512279ba7cee299d1d2be ntp.o.before.asm 1bf0b3be564512279ba7cee299d1d2be ntp.o.after.asm Signed-off-by: Ingo Molnar

time: ntp: simplify ntp_tick_adj calculations

2009-02-25T17:38:16Z

Impact: micro-optimization Convert the (internal) ntp_tick_adj value we store from unscaled units to scaled units. This is a constant that we never modify, so scaling it up once during bootup is enough - we dont have to do it for every adjustment step. Signed-off-by: Ingo Molnar

time: ntp: make 64-bit constants more robust

2009-02-25T17:38:15Z

Impact: cleanup, no functionality changed - make PPM_SCALE an explicit s64 constant, to remove (s64) casts from usage sites. kernel/time/ntp.o: text data bss dec hex filename 2536 114 136 2786 ae2 ntp.o.before 2536 114 136 2786 ae2 ntp.o.after md5: 40a7728d1188aa18e83e21a81fa7b150 ntp.o.before.asm 40a7728d1188aa18e83e21a81fa7b150 ntp.o.after.asm Signed-off-by: Ingo Molnar

time: ntp: refactor do_adjtimex() some more

2009-02-25T17:38:15Z

Impact: cleanup, no functionality changed Further simplify do_adjtimex(): - introduce the ntp_start_leap_timer() helper function - eliminate the goto adj_done complication Signed-off-by: Ingo Molnar