Re: [Crash-utility] patch for slight modification to runq -g command

-----Original Message----- From: crash-utility-bounces(a)redhat.com [mailto:crash-utility- bounces(a)redhat.com] On Behalf Of Dave Anderson Sent: Friday, November 08, 2013 5:58 AM To: Discussion list for crash utility usage, maintenance and development Subject: 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: 000000000000000000000000000000010000000000000000000000000000000 1 crash> eval 201908650262921217 hexadecimal: 2cd52d900000001 decimal: 201908650262921217 octal: 13152455440000000001 binary: 000000101100110101010010110110010000000000000000000000000000000 1 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 -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility