Messages in this thread | | | Date | Mon, 13 Feb 2012 19:15:07 +0100 | From | Igor Mammedov <> | Subject | Re: [PATCH RFC] pvclock: Make pv_clock more robust and fixup it if overflow happens |
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On 02/13/2012 06:48 PM, Marcelo Tosatti wrote: > On Mon, Feb 13, 2012 at 04:45:59PM +0100, Igor Mammedov wrote: >> Instead of hunting misterious stalls/hungs all over the kernel when >> overflow occurs at pvclock.c:pvclock_get_nsec_offset >> >> u64 delta = native_read_tsc() - shadow->tsc_timestamp; >> >> and introducing hooks when places of unexpected access found, pv_clock >> should be initialized for the calling cpu if overflow condition is detected. >> >> Signed-off-by: Igor Mammedov<imammedo@redhat.com> > > Igor, > > I disagree. This is fixing the symptom not the root cause. Additionally, > Xen also uses pvclock_clocksource_read. > > How about adding a BUG_ON to detect the overflow, this way hunting for > the problem is not necessary. > Ok, I'll repost bug_on version.
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