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Diffstat (limited to 'kernel/trace/trace_selftest.c')
-rw-r--r--kernel/trace/trace_selftest.c169
1 files changed, 142 insertions, 27 deletions
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index bc8e80a86bc..08f4eb2763d 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -1,5 +1,6 @@
/* Include in trace.c */
+#include <linux/stringify.h>
#include <linux/kthread.h>
#include <linux/delay.h>
@@ -9,11 +10,12 @@ static inline int trace_valid_entry(struct trace_entry *entry)
case TRACE_FN:
case TRACE_CTX:
case TRACE_WAKE:
- case TRACE_CONT:
case TRACE_STACK:
case TRACE_PRINT:
case TRACE_SPECIAL:
case TRACE_BRANCH:
+ case TRACE_GRAPH_ENT:
+ case TRACE_GRAPH_RET:
return 1;
}
return 0;
@@ -99,9 +101,6 @@ static inline void warn_failed_init_tracer(struct tracer *trace, int init_ret)
#ifdef CONFIG_DYNAMIC_FTRACE
-#define __STR(x) #x
-#define STR(x) __STR(x)
-
/* Test dynamic code modification and ftrace filters */
int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
struct trace_array *tr,
@@ -125,17 +124,17 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
func();
/*
- * Some archs *cough*PowerPC*cough* add charachters to the
+ * Some archs *cough*PowerPC*cough* add characters to the
* start of the function names. We simply put a '*' to
- * accomodate them.
+ * accommodate them.
*/
- func_name = "*" STR(DYN_FTRACE_TEST_NAME);
+ func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
/* filter only on our function */
ftrace_set_filter(func_name, strlen(func_name), 1);
/* enable tracing */
- ret = trace->init(tr);
+ ret = tracer_init(trace, tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
goto out;
@@ -209,7 +208,7 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
ftrace_enabled = 1;
tracer_enabled = 1;
- ret = trace->init(tr);
+ ret = tracer_init(trace, tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
goto out;
@@ -247,6 +246,90 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
}
#endif /* CONFIG_FUNCTION_TRACER */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+
+/* Maximum number of functions to trace before diagnosing a hang */
+#define GRAPH_MAX_FUNC_TEST 100000000
+
+static void __ftrace_dump(bool disable_tracing);
+static unsigned int graph_hang_thresh;
+
+/* Wrap the real function entry probe to avoid possible hanging */
+static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace)
+{
+ /* This is harmlessly racy, we want to approximately detect a hang */
+ if (unlikely(++graph_hang_thresh > GRAPH_MAX_FUNC_TEST)) {
+ ftrace_graph_stop();
+ printk(KERN_WARNING "BUG: Function graph tracer hang!\n");
+ if (ftrace_dump_on_oops)
+ __ftrace_dump(false);
+ return 0;
+ }
+
+ return trace_graph_entry(trace);
+}
+
+/*
+ * Pretty much the same than for the function tracer from which the selftest
+ * has been borrowed.
+ */
+int
+trace_selftest_startup_function_graph(struct tracer *trace,
+ struct trace_array *tr)
+{
+ int ret;
+ unsigned long count;
+
+ /*
+ * Simulate the init() callback but we attach a watchdog callback
+ * to detect and recover from possible hangs
+ */
+ tracing_reset_online_cpus(tr);
+ ret = register_ftrace_graph(&trace_graph_return,
+ &trace_graph_entry_watchdog);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ goto out;
+ }
+ tracing_start_cmdline_record();
+
+ /* Sleep for a 1/10 of a second */
+ msleep(100);
+
+ /* Have we just recovered from a hang? */
+ if (graph_hang_thresh > GRAPH_MAX_FUNC_TEST) {
+ tracing_selftest_disabled = true;
+ ret = -1;
+ goto out;
+ }
+
+ tracing_stop();
+
+ /* check the trace buffer */
+ ret = trace_test_buffer(tr, &count);
+
+ trace->reset(tr);
+ tracing_start();
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ goto out;
+ }
+
+ /* Don't test dynamic tracing, the function tracer already did */
+
+out:
+ /* Stop it if we failed */
+ if (ret)
+ ftrace_graph_stop();
+
+ return ret;
+}
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+
#ifdef CONFIG_IRQSOFF_TRACER
int
trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
@@ -256,7 +339,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
int ret;
/* start the tracing */
- ret = trace->init(tr);
+ ret = tracer_init(trace, tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
@@ -268,6 +351,14 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
local_irq_disable();
udelay(100);
local_irq_enable();
+
+ /*
+ * Stop the tracer to avoid a warning subsequent
+ * to buffer flipping failure because tracing_stop()
+ * disables the tr and max buffers, making flipping impossible
+ * in case of parallels max irqs off latencies.
+ */
+ trace->stop(tr);
/* stop the tracing. */
tracing_stop();
/* check both trace buffers */
@@ -310,7 +401,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
}
/* start the tracing */
- ret = trace->init(tr);
+ ret = tracer_init(trace, tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
@@ -322,6 +413,14 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
preempt_disable();
udelay(100);
preempt_enable();
+
+ /*
+ * Stop the tracer to avoid a warning subsequent
+ * to buffer flipping failure because tracing_stop()
+ * disables the tr and max buffers, making flipping impossible
+ * in case of parallels max preempt off latencies.
+ */
+ trace->stop(tr);
/* stop the tracing. */
tracing_stop();
/* check both trace buffers */
@@ -364,10 +463,10 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
}
/* start the tracing */
- ret = trace->init(tr);
+ ret = tracer_init(trace, tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
- goto out;
+ goto out_no_start;
}
/* reset the max latency */
@@ -381,31 +480,35 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
/* reverse the order of preempt vs irqs */
local_irq_enable();
+ /*
+ * Stop the tracer to avoid a warning subsequent
+ * to buffer flipping failure because tracing_stop()
+ * disables the tr and max buffers, making flipping impossible
+ * in case of parallels max irqs/preempt off latencies.
+ */
+ trace->stop(tr);
/* stop the tracing. */
tracing_stop();
/* check both trace buffers */
ret = trace_test_buffer(tr, NULL);
- if (ret) {
- tracing_start();
+ if (ret)
goto out;
- }
ret = trace_test_buffer(&max_tr, &count);
- if (ret) {
- tracing_start();
+ if (ret)
goto out;
- }
if (!ret && !count) {
printk(KERN_CONT ".. no entries found ..");
ret = -1;
- tracing_start();
goto out;
}
/* do the test by disabling interrupts first this time */
tracing_max_latency = 0;
tracing_start();
+ trace->start(tr);
+
preempt_disable();
local_irq_disable();
udelay(100);
@@ -413,6 +516,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
/* reverse the order of preempt vs irqs */
local_irq_enable();
+ trace->stop(tr);
/* stop the tracing. */
tracing_stop();
/* check both trace buffers */
@@ -428,9 +532,10 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
goto out;
}
- out:
- trace->reset(tr);
+out:
tracing_start();
+out_no_start:
+ trace->reset(tr);
tracing_max_latency = save_max;
return ret;
@@ -496,7 +601,7 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
wait_for_completion(&isrt);
/* start the tracing */
- ret = trace->init(tr);
+ ret = tracer_init(trace, tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
@@ -557,7 +662,7 @@ trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr
int ret;
/* start the tracing */
- ret = trace->init(tr);
+ ret = tracer_init(trace, tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
@@ -589,10 +694,10 @@ trace_selftest_startup_sysprof(struct tracer *trace, struct trace_array *tr)
int ret;
/* start the tracing */
- ret = trace->init(tr);
+ ret = tracer_init(trace, tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
- return 0;
+ return ret;
}
/* Sleep for a 1/10 of a second */
@@ -604,6 +709,11 @@ trace_selftest_startup_sysprof(struct tracer *trace, struct trace_array *tr)
trace->reset(tr);
tracing_start();
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ }
+
return ret;
}
#endif /* CONFIG_SYSPROF_TRACER */
@@ -616,7 +726,7 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr)
int ret;
/* start the tracing */
- ret = trace->init(tr);
+ ret = tracer_init(trace, tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
@@ -631,6 +741,11 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr)
trace->reset(tr);
tracing_start();
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ }
+
return ret;
}
#endif /* CONFIG_BRANCH_TRACER */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-15 21:16:18 +0000