Messages in this thread | | | Date | Fri, 11 Apr 2008 18:43:52 -0300 | From | "Gary Shi" <> | Subject | get a still sysrq-t call trace, not a moving one |
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Hi friends,
when I read sysrq-t call trace, I find the collected call trace for some cases is not a still snapshot, but a moving one. After checking show_state src, I realize other cpus are not frozen when one cpu is doing show_state; thus some task switching can occur among those cpus, even the cpu doing sysrq for some kind of kernels.
This moving call traces make debugging much more difficult, or even impossible for some cases, since some tasks have been switched in/out which make us lose the trace of some important data, like who is holding a lock when lots of threads are blocked on the lock.
In order to get a still image of sysrq-t call trace, I'd like to suggest freezing all other cpus and disabling irq of local cpu.
Any ideas about this?
Thanx -gys
pls cc me when you reply since I haven't subscribed to the mailing list.
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