Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'trace-v4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix a bug caused by not cleaning up the new instance unique triggers
when deleting an instance. It also creates a selftest that triggers
that bug.
- Fix the delayed optimization happening after kprobes boot up self
tests being removed by freeing of init memory.
- Comment kprobes on why the delay optimization is not a problem for
removal of modules, to keep other developers from searching that
riddle.
- Fix another case of rcu not watching in stack trace tracing.
* tag 'trace-v4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Make sure RCU is watching before calling a stack trace
kprobes: Document how optimized kprobes are removed from module unload
selftests/ftrace: Add test to remove instance with active event triggers
selftests/ftrace: Fix bashisms
ftrace: Remove #ifdef from code and add clear_ftrace_function_probes() stub
ftrace/instances: Clear function triggers when removing instances
ftrace: Simplify glob handling in unregister_ftrace_function_probe_func()
tracing/kprobes: Enforce kprobes teardown after testing
tracing: Move postpone selftests to core from early_initcall
+72
-11
+3
include/linux/kprobes.h
+3
include/linux/kprobes.h
···
349
349
int write, void __user *buffer,
350
350
size_t *length, loff_t *ppos);
351
351
#endif
352
+
extern void wait_for_kprobe_optimizer(void);
353
+
#else
354
+
static inline void wait_for_kprobe_optimizer(void) { }
352
355
#endif /* CONFIG_OPTPROBES */
353
356
#ifdef CONFIG_KPROBES_ON_FTRACE
354
357
extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
+7
-1
kernel/kprobes.c
+7
-1
kernel/kprobes.c
···
595
595
}
596
596
597
597
/* Wait for completing optimization and unoptimization */
598
-
static void wait_for_kprobe_optimizer(void)
598
+
void wait_for_kprobe_optimizer(void)
599
599
{
600
600
mutex_lock(&kprobe_mutex);
601
601
···
2183
2183
* The vaddr this probe is installed will soon
2184
2184
* be vfreed buy not synced to disk. Hence,
2185
2185
* disarming the breakpoint isn't needed.
2186
+
*
2187
+
* Note, this will also move any optimized probes
2188
+
* that are pending to be removed from their
2189
+
* corresponding lists to the freeing_list and
2190
+
* will not be touched by the delayed
2191
+
* kprobe_optimizer work handler.
2186
2192
*/
2187
2193
kill_kprobe(p);
2188
2194
}
+10
-2
kernel/trace/ftrace.c
+10
-2
kernel/trace/ftrace.c
···
4144
4144
int i, ret = -ENODEV;
4145
4145
int size;
4146
4146
4147
-
if (glob && (strcmp(glob, "*") == 0 || !strlen(glob)))
4147
+
if (!glob || !strlen(glob) || !strcmp(glob, "*"))
4148
4148
func_g.search = NULL;
4149
-
else if (glob) {
4149
+
else {
4150
4150
int not;
4151
4151
4152
4152
func_g.type = filter_parse_regex(glob, strlen(glob),
···
4254
4254
err_unlock_ftrace:
4255
4255
mutex_unlock(&ftrace_lock);
4256
4256
return ret;
4257
+
}
4258
+
4259
+
void clear_ftrace_function_probes(struct trace_array *tr)
4260
+
{
4261
+
struct ftrace_func_probe *probe, *n;
4262
+
4263
+
list_for_each_entry_safe(probe, n, &tr->func_probes, list)
4264
+
unregister_ftrace_function_probe_func(NULL, tr, probe->probe_ops);
4257
4265
}
4258
4266
4259
4267
static LIST_HEAD(ftrace_commands);
+32
-2
kernel/trace/trace.c
+32
-2
kernel/trace/trace.c
···
1558
1558
1559
1559
return 0;
1560
1560
}
1561
-
early_initcall(init_trace_selftests);
1561
+
core_initcall(init_trace_selftests);
1562
1562
#else
1563
1563
static inline int run_tracer_selftest(struct tracer *type)
1564
1564
{
···
2568
2568
void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
2569
2569
int pc)
2570
2570
{
2571
-
__ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL);
2571
+
struct ring_buffer *buffer = tr->trace_buffer.buffer;
2572
+
2573
+
if (rcu_is_watching()) {
2574
+
__ftrace_trace_stack(buffer, flags, skip, pc, NULL);
2575
+
return;
2576
+
}
2577
+
2578
+
/*
2579
+
* When an NMI triggers, RCU is enabled via rcu_nmi_enter(),
2580
+
* but if the above rcu_is_watching() failed, then the NMI
2581
+
* triggered someplace critical, and rcu_irq_enter() should
2582
+
* not be called from NMI.
2583
+
*/
2584
+
if (unlikely(in_nmi()))
2585
+
return;
2586
+
2587
+
/*
2588
+
* It is possible that a function is being traced in a
2589
+
* location that RCU is not watching. A call to
2590
+
* rcu_irq_enter() will make sure that it is, but there's
2591
+
* a few internal rcu functions that could be traced
2592
+
* where that wont work either. In those cases, we just
2593
+
* do nothing.
2594
+
*/
2595
+
if (unlikely(rcu_irq_enter_disabled()))
2596
+
return;
2597
+
2598
+
rcu_irq_enter_irqson();
2599
+
__ftrace_trace_stack(buffer, flags, skip, pc, NULL);
2600
+
rcu_irq_exit_irqson();
2572
2601
}
2573
2602
2574
2603
/**
···
7579
7550
}
7580
7551
7581
7552
tracing_set_nop(tr);
7553
+
clear_ftrace_function_probes(tr);
7582
7554
event_trace_del_tracer(tr);
7583
7555
ftrace_clear_pids(tr);
7584
7556
ftrace_destroy_function_files(tr);
+5
kernel/trace/trace.h
+5
kernel/trace/trace.h
···
980
980
extern int
981
981
unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
982
982
struct ftrace_probe_ops *ops);
983
+
extern void clear_ftrace_function_probes(struct trace_array *tr);
983
984
984
985
int register_ftrace_command(struct ftrace_func_command *cmd);
985
986
int unregister_ftrace_command(struct ftrace_func_command *cmd);
···
999
998
{
1000
999
return -EINVAL;
1001
1000
}
1001
+
static inline void clear_ftrace_function_probes(struct trace_array *tr)
1002
+
{
1003
+
}
1004
+
1002
1005
/*
1003
1006
* The ops parameter passed in is usually undefined.
1004
1007
* This must be a macro.
+5
kernel/trace/trace_kprobe.c
+5
kernel/trace/trace_kprobe.c
···
1535
1535
1536
1536
end:
1537
1537
release_all_trace_kprobes();
1538
+
/*
1539
+
* Wait for the optimizer work to finish. Otherwise it might fiddle
1540
+
* with probes in already freed __init text.
1541
+
*/
1542
+
wait_for_kprobe_optimizer();
1538
1543
if (warn)
1539
1544
pr_cont("NG: Some tests are failed. Please check them.\n");
1540
1545
else
+1
-1
tools/testing/selftests/ftrace/ftracetest
+1
-1
tools/testing/selftests/ftrace/ftracetest
+1
-1
tools/testing/selftests/ftrace/test.d/ftrace/func_event_triggers.tc
+1
-1
tools/testing/selftests/ftrace/test.d/ftrace/func_event_triggers.tc
+2
-2
tools/testing/selftests/ftrace/test.d/functions
+2
-2
tools/testing/selftests/ftrace/test.d/functions
···
34
34
echo > set_ftrace_filter
35
35
grep -v '^#' set_ftrace_filter | while read t; do
36
36
tr=`echo $t | cut -d: -f2`
37
-
if [ "$tr" == "" ]; then
37
+
if [ "$tr" = "" ]; then
38
38
continue
39
39
fi
40
-
if [ $tr == "enable_event" -o $tr == "disable_event" ]; then
40
+
if [ $tr = "enable_event" -o $tr = "disable_event" ]; then
41
41
tr=`echo $t | cut -d: -f1-4`
42
42
limit=`echo $t | cut -d: -f5`
43
43
else
+6
-2
tools/testing/selftests/ftrace/test.d/instances/instance-event.tc
+6
-2
tools/testing/selftests/ftrace/test.d/instances/instance-event.tc