Weird ISR accounting in 10-STABLE

[Vlad Galu]

CPU information:
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FreeBSD/SMP: Multiprocessor System Detected: 8 CPUs
FreeBSD/SMP: 1 package(s) x 4 core(s) x 2 SMT threads
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top output:
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last pid: 51987;  load averages:  2.00,  2.00,  2.00



                                     up 8+18:47:58  13:07:02
520 processes: 11 running, 489 sleeping, 20 waiting
CPU 0:  0.0% user,  0.0% nice,  0.0% system,  0.0% interrupt,  100% idle
CPU 1:  0.0% user,  0.0% nice,  0.0% system,  100% interrupt,  0.0% idle
CPU 2:  0.0% user,  0.0% nice,  0.4% system,  0.0% interrupt, 99.6% idle
CPU 3:  0.4% user,  0.0% nice,  0.0% system,  0.0% interrupt, 99.6% idle
CPU 4:  0.0% user,  0.0% nice,  0.0% system,  0.0% interrupt,  100% idle
CPU 5:  0.0% user,  0.0% nice,  0.8% system,  0.0% interrupt, 99.2% idle
CPU 6:  0.0% user,  0.0% nice,  0.4% system,  0.0% interrupt, 99.6% idle
CPU 7:  0.0% user,  0.0% nice,  0.0% system,  0.4% interrupt, 99.6% idle
Mem: 87M Active, 2102M Inact, 11G Wired, 3656K Cache, 17G Free
ARC: 8192M Total, 4089M MFU, 3372M MRU, 1936K Anon, 66M Header, 663M Other
Swap: 32G Total, 32G Free

  PID USERNAME      PRI NICE   SIZE    RES STATE   C   TIME    WCPU COMMAND
   11 root          155 ki31     0K   128K CPU0    0 210.1H 100.00%
idle{idle: cpu0}
   11 root          155 ki31     0K   128K CPU5    5 209.9H 100.00%
idle{idle: cpu5}
   11 root          155 ki31     0K   128K CPU7    7 209.9H 100.00%
idle{idle: cpu7}
   11 root          155 ki31     0K   128K CPU4    4 209.1H 100.00%
idle{idle: cpu4}
   11 root          155 ki31     0K   128K RUN     3 189.9H 100.00%
idle{idle: cpu3}
   11 root          155 ki31     0K   128K CPU2    2 173.3H 100.00%
idle{idle: cpu2}
   11 root          155 ki31     0K   128K CPU6    6 163.4H 100.00%
idle{idle: cpu6}
   12 root          -72    -     0K   336K CPU1    1 141.0H 100.00%
intr{swi1: netisr 0}
   11 root          155 ki31     0K   128K RUN     1 169.3H   0.00%
idle{idle: cpu1}
   12 root          -92    -     0K   336K WAIT    7  31:16   0.00%
intr{irq265: re0}
   23 root           16    -     0K    16K syncer  2   9:38   0.00% syncer
    7 root          -16    -     0K    16K pftm    5   9:35   0.00% pf purge
   12 root          -60    -     0K   336K WAIT    0   4:26   0.00%
intr{swi4: clock}
   15 root          -16    -     0K    16K -       5   3:13   0.00%
rand_harvestq
   12 root          -88    -     0K   336K WAIT    3   1:15   0.00%
intr{irq266: ahci0}
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vmstat output:
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interrupt                          total       rate
irq1: atkbd0                          76          0
irq16: ehci0                     1312187          1
irq23: ehci1                     2365530          3
cpu0:timer                     840112732       1106
irq265: re0                    490701654        646
irq266: ahci0                   20242836         26
cpu1:timer                     842936638       1110
cpu4:timer                     840150578       1106
cpu6:timer                     842568978       1110
cpu7:timer                     839981052       1106
cpu3:timer                     841067527       1108
cpu5:timer                     839980632       1106
cpu2:timer                     842451888       1109
Total                         7243872308       9543
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This idle system runs #r267282. I can't figure out what is getting
accounted towards interrupt handling.

P.S. Please CC me, thanks.
Vlad