path: root/lib/kernel_lock.c
diff options
authorFrederic Weisbecker <>2009-09-28 17:12:49 +0200
committerFrederic Weisbecker <>2009-09-28 18:00:48 +0200
commit925936ebf35a95c290e010b784c962164e6728f3 (patch)
treee0bae3a2655f84dcf238c9acacd158e5ce422b32 /lib/kernel_lock.c
parent3f6fe06dbf67b46d36fedec502300e04dffeb67a (diff)
tracing: Pushdown the bkl tracepoints calls
Currently we are calling the bkl tracepoint callbacks just before the bkl lock/unlock operations, ie the tracepoint call is not inside a lock_kernel() function but inside a lock_kernel() macro. Hence the bkl trace event header must be included from smp_lock.h. This raises some nasty circular header dependencies: linux/smp_lock.h -> trace/events/bkl.h -> trace/define_trace.h -> trace/ftrace.h -> linux/ftrace_event.h -> linux/hardirq.h -> linux/smp_lock.h This results in incomplete event declarations, spurious event definitions and other kind of funny behaviours. This is hardly fixable without ugly workarounds. So instead, we push the file name, line number and function name as lock_kernel() parameters, so that we only deal with the trace event header from lib/kernel_lock.c This adds two parameters to lock_kernel() and unlock_kernel() but it should be fine wrt to performances because this pair dos not seem to be called in fast paths. Signed-off-by: Frederic Weisbecker <> Cc: Steven Rostedt <> Cc: Ingo Molnar <> Cc: Li Zefan <>
Diffstat (limited to 'lib/kernel_lock.c')
1 files changed, 11 insertions, 4 deletions
diff --git a/lib/kernel_lock.c b/lib/kernel_lock.c
index 5c10b2e1fd08..4ebfa5a164d7 100644
--- a/lib/kernel_lock.c
+++ b/lib/kernel_lock.c
@@ -8,9 +8,11 @@
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/semaphore.h>
#include <linux/smp_lock.h>
+#include <trace/events/bkl.h>
* The 'big kernel lock'
@@ -114,19 +116,24 @@ static inline void __unlock_kernel(void)
* This cannot happen asynchronously, so we only need to
* worry about other CPU's.
-void __lockfunc _lock_kernel(void)
+void __lockfunc _lock_kernel(const char *func, const char *file, int line)
- int depth = current->lock_depth+1;
+ int depth = current->lock_depth + 1;
+ trace_lock_kernel(func, file, line);
if (likely(!depth))
current->lock_depth = depth;
-void __lockfunc _unlock_kernel(void)
+void __lockfunc _unlock_kernel(const char *func, const char *file, int line)
BUG_ON(current->lock_depth < 0);
if (likely(--current->lock_depth < 0))
+ trace_unlock_kernel(func, file, line);