[PATCH] simple preemption debug check
authorRobert Love <rml@tech9.net>
Wed, 3 Apr 2002 08:45:42 +0000 (00:45 -0800)
committerDave Jones <davej@suse.de>
Wed, 3 Apr 2002 08:45:42 +0000 (00:45 -0800)
commit6a1a68c8febfc71c895a05a10afe6812b7c77584
tree3199da192742640421a049f821a3bd233d8e5599
parentda6b470391b402d49e76baf7b28dbfd390eaa7eb
[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
include/linux/spinlock.h
kernel/exit.c