On Thu, 2013-01-10 at 13:58 -0600, Shawn Bohrer wrote: > Here is the output: > > [ 81.278842] SysRq : Changing Loglevel > [ 81.279027] Loglevel set to 9 > [ 83.285456] Initial want: 50000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 900000000 > [ 85.286452] Initial want: 50000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 900000000 > [ 85.289625] Initial want: 50000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 900000000 > [ 87.287435] Initial want: 100000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 850000000 > [ 87.290718] Initial want: 50000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 900000000 > [ 89.288469] Initial want: -50000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 1000000000 > [ 89.291550] Initial want: 150000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 800000000 > [ 89.292940] Initial want: 100000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 850000000 > [ 89.294082] Initial want: 100000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 850000000 > [ 89.295194] Initial want: 50000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 900000000 > [ 89.296274] Initial want: 50000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 900000000 > [ 90.959004] [sched_delayed] sched: RT throttling activated > [ 91.289470] Initial want: 200000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 750000000 > [ 91.292767] Initial want: 200000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 750000000 > [ 91.294037] Initial want: 200000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 750000000 > [ 91.295364] Initial want: 200000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 750000000 > [ 91.296355] BUG triggered, want: 200000000 > [ 91.296355] > [ 91.296355] rt_rq[7]: > [ 91.296355] .rt_nr_running : 0 > [ 91.296355] .rt_throttled : 0 > [ 91.296355] .rt_time : 0.000000 > [ 91.296355] .rt_runtime : 750.000000 > [ 91.307332] Initial want: -50000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 1000000000 > [ 91.308440] Initial want: -100000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 1050000000 > [ 91.309586] Initial want: -150000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 1100000000 > [ 91.310716] Initial want: -200000000 rt_b->rt_runtime: 950000000 > rt_rq->rt_runtime: 1150000000 > [ 91.311707] BUG triggered, want: -200000000 > [ 91.311707] > [ 91.311707] rt_rq[6]: > [ 91.311707] .rt_nr_running : 1 > [ 91.311707] .rt_throttled : 0 > [ 91.311707] .rt_time : 307.209987 > [ 91.311707] .rt_runtime : 1150.000000
That makes about as much sense as my crash did. There is no leak, but cpu found nada. So rd/span is changing on us? We saw nada as we traversed, release locks, poof, it's there. In my dump, at crash time, rd/span was fine, but at the top of the stack, I found a mighty suspicious reference to def_root_domain.span. At _crash_ time, both it and rq->rd.span had pilfer-able goodies, but whatever it was that we traversed had nada just a wee bit earlier. If the darn thing would trigger for me again, I'd use trace_printk(), check rd and cpumask_weight(rd->span) before/after traverse, print cpu and rt_runtime as we traverse, set /proc/sys/kernel/ftrace_dump_on_oops to 1.. and hope bug doesn't like to play heisenbug games. -Mike -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
