Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'trace-fixes-v3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"This includes a fix to a memory leak when adding filters to traces.
Also, Masami Hiramatsu fixed up some minor bugs that were discovered
by sparse."
* tag 'trace-fixes-v3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/kprobes: Make print_*probe_event static
tracing/kprobes: Fix a sparse warning for incorrect type in assignment
tracing/kprobes: Use rcu_dereference_raw for tp->files
tracing: Fix leaks of filter preds
+44
-13
+4
kernel/trace/trace_events_filter.c
+4
kernel/trace/trace_events_filter.c
+40
-13
kernel/trace/trace_kprobe.c
+40
-13
kernel/trace/trace_kprobe.c
···
35
35
const char *symbol; /* symbol name */
36
36
struct ftrace_event_class class;
37
37
struct ftrace_event_call call;
38
-
struct ftrace_event_file **files;
38
+
struct ftrace_event_file * __rcu *files;
39
39
ssize_t size; /* trace entry size */
40
40
unsigned int nr_args;
41
41
struct probe_arg args[];
···
185
185
186
186
static int trace_probe_nr_files(struct trace_probe *tp)
187
187
{
188
-
struct ftrace_event_file **file = tp->files;
188
+
struct ftrace_event_file **file;
189
189
int ret = 0;
190
190
191
+
/*
192
+
* Since all tp->files updater is protected by probe_enable_lock,
193
+
* we don't need to lock an rcu_read_lock.
194
+
*/
195
+
file = rcu_dereference_raw(tp->files);
191
196
if (file)
192
197
while (*(file++))
193
198
ret++;
···
214
209
mutex_lock(&probe_enable_lock);
215
210
216
211
if (file) {
217
-
struct ftrace_event_file **new, **old = tp->files;
212
+
struct ftrace_event_file **new, **old;
218
213
int n = trace_probe_nr_files(tp);
219
214
215
+
old = rcu_dereference_raw(tp->files);
220
216
/* 1 is for new one and 1 is for stopper */
221
217
new = kzalloc((n + 2) * sizeof(struct ftrace_event_file *),
222
218
GFP_KERNEL);
···
257
251
static int
258
252
trace_probe_file_index(struct trace_probe *tp, struct ftrace_event_file *file)
259
253
{
254
+
struct ftrace_event_file **files;
260
255
int i;
261
256
262
-
if (tp->files) {
263
-
for (i = 0; tp->files[i]; i++)
264
-
if (tp->files[i] == file)
257
+
/*
258
+
* Since all tp->files updater is protected by probe_enable_lock,
259
+
* we don't need to lock an rcu_read_lock.
260
+
*/
261
+
files = rcu_dereference_raw(tp->files);
262
+
if (files) {
263
+
for (i = 0; files[i]; i++)
264
+
if (files[i] == file)
265
265
return i;
266
266
}
267
267
···
286
274
mutex_lock(&probe_enable_lock);
287
275
288
276
if (file) {
289
-
struct ftrace_event_file **new, **old = tp->files;
277
+
struct ftrace_event_file **new, **old;
290
278
int n = trace_probe_nr_files(tp);
291
279
int i, j;
292
280
281
+
old = rcu_dereference_raw(tp->files);
293
282
if (n == 0 || trace_probe_file_index(tp, file) < 0) {
294
283
ret = -EINVAL;
295
284
goto out_unlock;
···
885
872
static __kprobes void
886
873
kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs)
887
874
{
888
-
struct ftrace_event_file **file = tp->files;
875
+
/*
876
+
* Note: preempt is already disabled around the kprobe handler.
877
+
* However, we still need an smp_read_barrier_depends() corresponding
878
+
* to smp_wmb() in rcu_assign_pointer() to access the pointer.
879
+
*/
880
+
struct ftrace_event_file **file = rcu_dereference_raw(tp->files);
889
881
890
-
/* Note: preempt is already disabled around the kprobe handler */
882
+
if (unlikely(!file))
883
+
return;
884
+
891
885
while (*file) {
892
886
__kprobe_trace_func(tp, regs, *file);
893
887
file++;
···
945
925
kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri,
946
926
struct pt_regs *regs)
947
927
{
948
-
struct ftrace_event_file **file = tp->files;
928
+
/*
929
+
* Note: preempt is already disabled around the kprobe handler.
930
+
* However, we still need an smp_read_barrier_depends() corresponding
931
+
* to smp_wmb() in rcu_assign_pointer() to access the pointer.
932
+
*/
933
+
struct ftrace_event_file **file = rcu_dereference_raw(tp->files);
949
934
950
-
/* Note: preempt is already disabled around the kprobe handler */
935
+
if (unlikely(!file))
936
+
return;
937
+
951
938
while (*file) {
952
939
__kretprobe_trace_func(tp, ri, regs, *file);
953
940
file++;
···
962
935
}
963
936
964
937
/* Event entry printers */
965
-
enum print_line_t
938
+
static enum print_line_t
966
939
print_kprobe_event(struct trace_iterator *iter, int flags,
967
940
struct trace_event *event)
968
941
{
···
998
971
return TRACE_TYPE_PARTIAL_LINE;
999
972
}
1000
973
1001
-
enum print_line_t
974
+
static enum print_line_t
1002
975
print_kretprobe_event(struct trace_iterator *iter, int flags,
1003
976
struct trace_event *event)
1004
977
{