perf_counter: Sanitize counter->mutex
s/counter->mutex/counter->child_mutex/ and make sure its only
used to protect child_list.
The usage in __perf_counter_exit_task() doesn't appear to be
problematic since ctx->mutex also covers anything related to fd
tear-down.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090523163012.533186528@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index 23ddd29..4ab8050 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -452,9 +452,6 @@
struct perf_counter_context *ctx;
struct file *filp;
- struct perf_counter *parent;
- struct list_head child_list;
-
/*
* These accumulate total time (in nanoseconds) that children
* counters have been enabled and running, respectively.
@@ -465,7 +462,9 @@
/*
* Protect attach/detach and child_list:
*/
- struct mutex mutex;
+ struct mutex child_mutex;
+ struct list_head child_list;
+ struct perf_counter *parent;
int oncpu;
int cpu;