[PATCH] mutex subsystem, more debugging code

more mutex debugging: check for held locks during memory freeing,
task exit, enable sysrq printouts, etc.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>

kernel/exit.c

diff --git a/kernel/exit.c b/kernel/exit.c
index caceabf..309a46f 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -29,6 +29,7 @@
 #include <linux/syscalls.h>
 #include <linux/signal.h>
 #include <linux/cn_proc.h>
+#include <linux/mutex.h>
 
 #include <asm/uaccess.h>
 #include <asm/unistd.h>
@@ -869,6 +870,10 @@
 	mpol_free(tsk->mempolicy);
 	tsk->mempolicy = NULL;
 #endif
+	/*
+	 * If DEBUG_MUTEXES is on, make sure we are holding no locks:
+	 */
+	mutex_debug_check_no_locks_held(tsk);
 
 	/* PF_DEAD causes final put_task_struct after we schedule. */
 	preempt_disable();

kernel/sched.c

diff --git a/kernel/sched.c b/kernel/sched.c
index 9273309..34a945b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4386,6 +4386,7 @@
 	} while_each_thread(g, p);
 
 	read_unlock(&tasklist_lock);
+	mutex_debug_show_all_locks();
 }
 
 /**