Re: [Crash-utility] patch for slight modification to runq -g command
----- Original Message -----
The "runq -g" output for that cpu looks like this:
CPU 1
CURRENT: PID: 1212 CFS: ffff880035cc2f00 TASK: ffff880035f60000
COMMAND: "bash"
TASK_GROUP RT_RQ: ffff88007fa541e8
RT PRIO_ARRAY: ffff88007fa541e8
[no tasks queued]
TASK_GROUP CFS_RQ: ffff88007fa540f0
CFS RB_ROOT: ffff88007fa54118
GROUP: ffff880078af7800 CFS_RQ: ffff880035cc2f00 RB_ROOT: ffff880035cc2f28
nr_running: 4294967297 h_nr_running: 201908650262921217
[120] PID: 1212 TASK: ffff880035f60000 COMMAND: "bash"
I don't understand where those values are coming from, because if
I look at the CFS_RQ, it shows this:
crash> cfs_rq.nr_running,h_nr_running ffff880035cc2f00
nr_running = 1
h_nr_running = 1
crash>
The problem above is due to the fact that both nr_running and h_nr_running
are of type unsigned int but your patch reads each of them as a ulong:
crash> eval 4294967297
hexadecimal: 100000001
decimal: 4294967297
octal: 40000000001
binary: 0000000000000000000000000000000100000000000000000000000000000001
crash> eval 201908650262921217
hexadecimal: 2cd52d900000001
decimal: 201908650262921217
octal: 13152455440000000001
binary: 0000001011001101010100101101100100000000000000000000000000000001
crash>
+ readmem(cfs_rq + OFFSET(cfs_rq_nr_running), KVADDR,
+ &nr_running, sizeof(ulong), "cfs_rq nr_running",
+ FAULT_ON_ERROR);
+ if (VALID_MEMBER(cfs_rq_h_nr_running)) {
+ readmem(cfs_rq + OFFSET(cfs_rq_h_nr_running), KVADDR,
+ &h_nr_running, sizeof(ulong), "cfs_rq
h_nr_running",
+ FAULT_ON_ERROR);
+ fprintf(fp, " nr_running: %lu h_nr_running: %lu ", nr_running,
h_nr_running);
+ } else {
+ fprintf(fp, " nr_running: %lu ", nr_running);
+ }
But again, I don't seen any compelling reason to display them at all -- especially
now that your patch displays the cfs_rq from which they come. If you really
need to see their values, just dump the data structure.
And as I mentioned earlier, the CFS address in the CURRENT: line is confusing and
redundant. Perhaps you could clarify things by appending "[CURRENT]" after
the task identifier in the queue, i.e., like:
[120] PID: 9048 TASK: ffff8808b07e4200 COMMAND: "actmain" [CURRENT]
Thanks,
Dave