So here is another round of this series, which is the result of earlier discussions with Linus and his suggestions around improvements to clocksource validation in the hope we can more easily catch bad hardware.
There's also a few cleanups Linus suggested as well as a few I've been meaning to get to for awhile. I tried in address all the feedback that had been given, adding the checks behind CONFIG_DEBUG_TIMEKEEPING. I also sorted out a sane way to print rate-limited warnings if we see cycle deltas that are too large, or if they look like small underflows. I'd like to get this queued into -tip soon so it can get as much testing in -next as possible. If there are any objections or feedback, I'd love to hear it! New in v4: * Lots and lots of typo corrections and minor cleanups suggested by Ingo. * Dropped "Remove clocksource_max_deferment()" patch * Added "Rename __clocksource_updatefreq_*..." patch * I realized one of the patches (Improve clocksource watchdog reporting) didn't have a proper cc list, so while it was on lkml folks may not have reviewed it before. thanks -john Cc: Dave Jones <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Richard Cochran <[email protected]> Cc: Prarit Bhargava <[email protected]> Cc: Stephen Boyd <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Peter Zijlstra <[email protected]> John Stultz (12): clocksource: Simplify clocks_calc_max_nsecs logic clocksource: Simplify logic around clocksource wrapping safety margins clocksource: Add max_cycles to clocksource structure time: Add debugging checks to warn if we see delays time: Add infrastructure to cap clocksource reads to the max_cycles value time: Try to catch clocksource delta underflows time: Add warnings when overflows or underflows are observed clocksource: Improve clocksource watchdog reporting clocksource: Mostly kill clocksource_register() sparc: Convert to using clocksource_register_hz() clocksource: Add some debug info about clocksources being registered clocksource: Rename __clocksource_updatefreq_* to __clocksource_update_freq_* arch/arm/plat-omap/counter_32k.c | 2 +- arch/s390/kernel/time.c | 2 +- arch/sparc/kernel/time_32.c | 6 +- drivers/clocksource/em_sti.c | 2 +- drivers/clocksource/sh_cmt.c | 2 +- drivers/clocksource/sh_tmu.c | 2 +- include/linux/clocksource.h | 26 ++++-- kernel/time/clocksource.c | 171 ++++++++++++++++++--------------------- kernel/time/jiffies.c | 5 +- kernel/time/sched_clock.c | 6 +- kernel/time/timekeeping.c | 127 ++++++++++++++++++++++++++--- lib/Kconfig.debug | 12 +++ 12 files changed, 235 insertions(+), 128 deletions(-) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
