diff options
| author | Robert Love <rml@tech9.net> | 2002-04-03 00:45:42 -0800 |
|---|---|---|
| committer | Dave Jones <davej@suse.de> | 2002-04-03 00:45:42 -0800 |
| commit | 6a1a68c8febfc71c895a05a10afe6812b7c77584 (patch) | |
| tree | 3199da192742640421a049f821a3bd233d8e5599 /kernel/exit.c | |
| parent | da6b470391b402d49e76baf7b28dbfd390eaa7eb (diff) | |
[PATCH] simple preemption debug check
This simple check was first suggested by Andrew Morton. Pretty basic -
whines if a task exits with a nonzero preempt_count value.
I put an identical check in the 2.4 preempt-kernel patch and - sure
enough - it was found that XFS essentially disables preemption as it
destroys data structures containing locks without first unlocking. The
SGI folks are working on that.
Anyhow, its a quick and clean solution to debugging potential problems.
Patch is against 2.5.7, please apply.
Robert Love
Diffstat (limited to 'kernel/exit.c')
| -rw-r--r-- | kernel/exit.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index d1a6b1451619..96472474ada7 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -490,6 +490,11 @@ NORET_TYPE void do_exit(long code) tsk->flags |= PF_EXITING; del_timer_sync(&tsk->real_timer); + if (unlikely(preempt_get_count())) + printk(KERN_ERR "error: %s[%d] exited with preempt_count %d\n", + current->comm, current->pid, + preempt_get_count()); + fake_volatile: acct_process(code); __exit_mm(tsk); |