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Diffstat (limited to 'kernel/trace/trace_kprobe.c')
-rw-r--r--kernel/trace/trace_kprobe.c47
1 files changed, 36 insertions, 11 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index eb6c9f1d3a93..a133ecd741e4 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -73,6 +73,17 @@ static nokprobe_inline bool trace_kprobe_is_on_module(struct trace_kprobe *tk)
return !!strchr(trace_kprobe_symbol(tk), ':');
}
+static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk)
+{
+ unsigned long nhit = 0;
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ nhit += *per_cpu_ptr(tk->nhit, cpu);
+
+ return nhit;
+}
+
static int register_kprobe_event(struct trace_kprobe *tk);
static int unregister_kprobe_event(struct trace_kprobe *tk);
@@ -882,14 +893,10 @@ static const struct file_operations kprobe_events_ops = {
static int probes_profile_seq_show(struct seq_file *m, void *v)
{
struct trace_kprobe *tk = v;
- unsigned long nhit = 0;
- int cpu;
-
- for_each_possible_cpu(cpu)
- nhit += *per_cpu_ptr(tk->nhit, cpu);
seq_printf(m, " %-44s %15lu %15lu\n",
- trace_event_name(&tk->tp.call), nhit,
+ trace_event_name(&tk->tp.call),
+ trace_kprobe_nhit(tk),
tk->rp.kp.nmissed);
return 0;
@@ -1354,18 +1361,18 @@ fs_initcall(init_kprobe_trace);
#ifdef CONFIG_FTRACE_STARTUP_TEST
-
/*
* The "__used" keeps gcc from removing the function symbol
- * from the kallsyms table.
+ * from the kallsyms table. 'noinline' makes sure that there
+ * isn't an inlined version used by the test method below
*/
-static __used int kprobe_trace_selftest_target(int a1, int a2, int a3,
- int a4, int a5, int a6)
+static __used __init noinline int
+kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int a5, int a6)
{
return a1 + a2 + a3 + a4 + a5 + a6;
}
-static struct trace_event_file *
+static struct __init trace_event_file *
find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr)
{
struct trace_event_file *file;
@@ -1443,12 +1450,25 @@ static __init int kprobe_trace_self_tests_init(void)
ret = target(1, 2, 3, 4, 5, 6);
+ /*
+ * Not expecting an error here, the check is only to prevent the
+ * optimizer from removing the call to target() as otherwise there
+ * are no side-effects and the call is never performed.
+ */
+ if (ret != 21)
+ warn++;
+
/* Disable trace points before removing it */
tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM);
if (WARN_ON_ONCE(tk == NULL)) {
pr_warn("error on getting test probe.\n");
warn++;
} else {
+ if (trace_kprobe_nhit(tk) != 1) {
+ pr_warn("incorrect number of testprobe hits\n");
+ warn++;
+ }
+
file = find_trace_probe_file(tk, top_trace_array());
if (WARN_ON_ONCE(file == NULL)) {
pr_warn("error on getting probe file.\n");
@@ -1462,6 +1482,11 @@ static __init int kprobe_trace_self_tests_init(void)
pr_warn("error on getting 2nd test probe.\n");
warn++;
} else {
+ if (trace_kprobe_nhit(tk) != 1) {
+ pr_warn("incorrect number of testprobe2 hits\n");
+ warn++;
+ }
+
file = find_trace_probe_file(tk, top_trace_array());
if (WARN_ON_ONCE(file == NULL)) {
pr_warn("error on getting probe file.\n");