linux_dsm_epyc7002/kernel/sched
Vegard Nossum d1c6d149cf sched/debug: Make the "Preemption disabled at ..." message more useful
This message is currently really useless since it always prints a value
that comes from the printk() we just did, e.g.:

    BUG: sleeping function called from invalid context at mm/slab.h:388
    in_atomic(): 0, irqs_disabled(): 0, pid: 31996, name: trinity-c1
    Preemption disabled at:[<ffffffff8119db33>] down_trylock+0x13/0x80

    BUG: sleeping function called from invalid context at include/linux/freezer.h:56
    in_atomic(): 0, irqs_disabled(): 0, pid: 31996, name: trinity-c1
    Preemption disabled at:[<ffffffff811aaa37>] console_unlock+0x2f7/0x930

Here, both down_trylock() and console_unlock() is somewhere in the
printk() path.

We should save the value before calling printk() and use the saved value
instead. That immediately reveals the offending callsite:

    BUG: sleeping function called from invalid context at mm/slab.h:388
    in_atomic(): 0, irqs_disabled(): 0, pid: 14971, name: trinity-c2
    Preemption disabled at:[<ffffffff819bcd46>] rhashtable_walk_start+0x46/0x150

Bug report:

  http://marc.info/?l=linux-netdev&m=146925979821849&w=2

Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russel <rusty@rustcorp.com.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 16:07:20 +02:00
..
auto_group.c sched/core: Move the sched_to_prio[] arrays out of line 2015-12-04 10:34:46 +01:00
auto_group.h sched, timer: Convert usages of ACCESS_ONCE() in the scheduler to READ_ONCE()/WRITE_ONCE() 2015-05-08 12:11:32 +02:00
clock.c sched/clock: Make local_clock()/cpu_clock() inline 2016-04-13 12:25:22 +02:00
completion.c sched/completion: Serialize completion_done() with complete() 2015-02-18 14:27:40 +01:00
core.c sched/debug: Make the "Preemption disabled at ..." message more useful 2016-08-10 16:07:20 +02:00
cpuacct.c sched/cpuacct: Introduce cpuacct.usage_all to show all CPU stats together 2016-07-09 13:56:15 +02:00
cpuacct.h sched/cpuacct: Simplify the cpuacct code 2016-03-21 11:00:28 +01:00
cpudeadline.c sched/deadline: Fix wrap-around in DL heap 2016-08-10 13:32:55 +02:00
cpudeadline.h sched/deadline: Unify dl_time_before() usage 2015-09-23 09:51:25 +02:00
cpufreq_schedutil.c cpufreq: schedutil: map raw required frequency to driver frequency 2016-07-21 22:28:21 +02:00
cpufreq.c cpufreq: sched: Helpers to add and remove update_util hooks 2016-04-02 01:08:43 +02:00
cpupri.c sched/core: Use tsk_cpus_allowed() instead of accessing ->cpus_allowed 2016-05-12 09:55:35 +02:00
cpupri.h sched/cpupri: Remove unnecessary definitions in cpupri.h 2014-11-16 10:58:59 +01:00
cputime.c xen: features and fixes for 4.8-rc0 2016-07-27 11:35:37 -07:00
deadline.c sched/deadline: Remove useless parameter from setup_new_dl_entity() 2016-08-10 14:03:32 +02:00
debug.c sched/debug: Always show 'nr_migrations' 2016-06-08 14:34:49 +02:00
fair.c sched/fair: Optimize find_idlest_cpu() when there is no choice 2016-08-10 14:03:32 +02:00
features.h sched/fair: Convert arch_scale_cpu_capacity() from weak function to #define 2015-09-13 09:52:55 +02:00
idle_task.c locking/lockdep, sched/core: Implement a better lock pinning scheme 2016-05-05 09:23:59 +02:00
idle.c Merge branch 'sched/urgent' into sched/core, to pick up fixes 2016-06-14 11:04:13 +02:00
loadavg.c sched/core: Correct off by one bug in load migration calculation 2016-07-13 14:58:20 +02:00
Makefile cpufreq: schedutil: New governor based on scheduler utilization data 2016-04-02 01:09:12 +02:00
rt.c sched/core: Provide a tsk_nr_cpus_allowed() helper 2016-05-12 09:55:36 +02:00
sched.h Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-07-25 13:59:34 -07:00
stats.c sched: use %*pb[l] to print bitmaps including cpumasks and nodemasks 2015-02-13 21:21:37 -08:00
stats.h sched/debug: Fix /proc/sched_debug regression 2016-06-08 14:31:58 +02:00
stop_task.c locking/lockdep, sched/core: Implement a better lock pinning scheme 2016-05-05 09:23:59 +02:00
swait.c wait.[ch]: Introduce the simple waitqueue (swait) implementation 2016-02-25 11:27:16 +01:00
wait.c sched/wait: Fix the signal handling fix 2015-12-13 14:30:59 -08:00