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| author | Vegard Nossum <vegard.nossum@oracle.com> | 2016-07-23 10:46:39 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-08-10 17:07:20 +0300 |
| commit | d1c6d149cf04d6c7c3c3ebf4b66c82500cbcf6e1 (patch) | |
| tree | 3d01d827276831e14611dec9bbe889cd9139bc85 /include/linux/sched.h | |
| parent | 98b0a857805080db04f50b8c71438c9c369ef0b3 (diff) | |
| download | linux-d1c6d149cf04d6c7c3c3ebf4b66c82500cbcf6e1.tar.xz | |
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>
Diffstat (limited to 'include/linux/sched.h')
| -rw-r--r-- | include/linux/sched.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index f3db596efd2c..7f64e89a5873 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -3236,6 +3236,15 @@ static inline void cond_resched_rcu(void) #endif } +static inline unsigned long get_preempt_disable_ip(struct task_struct *p) +{ +#ifdef CONFIG_DEBUG_PREEMPT + return p->preempt_disable_ip; +#else + return 0; +#endif +} + /* * Does a critical section need to be broken due to another * task waiting?: (technically does not depend on CONFIG_PREEMPT, |