Messages in this thread | | | Date | Sat, 27 Mar 2010 15:03:55 -0700 | From | Joel Becker <> | Subject | Re: [PATCH] hangcheck-timer is broken on x86 |
| |
On Fri, Mar 26, 2010 at 10:02:59PM -0400, Yury Polyanskiy wrote: > Joel, just realized there is a slight mistake in what I said before. > getrawmonotonic() is a refined jiffies (and actually resolves to > get_cycles() on my system in the end). Thus it doesn't count while in > suspend. However, jiffies-based timers (aka timer-wheel) are also > stopped while in suspend. So getrawmonotonic() is the right call to > check the precision of the jiffies-based timer (i.e. you dont need to > make a correction by calling monotonic_to_bootbased()).
It's OK to tell hangcheck-timer users that suspend is not allowed. After all, you're running something that you don't want to see hang. Is there a clock in the system that is a true wallclock? I'm guessing, since getrawmonotonic() is get_cycles() based, that it doesn't provide accurate time in the face of cpufreq changes. Is that true?
Joel
--
Life's Little Instruction Book #497
"Go down swinging."
Joel Becker Principal Software Developer Oracle E-mail: joel.becker@oracle.com Phone: (650) 506-8127
| |