Merge branch 'tracing/core-v2' into tracing-for-linus

Conflicts:
	include/linux/slub_def.h
	lib/Kconfig.debug
	mm/slob.c
	mm/slub.c

1 files changed, 142 insertions, 27 deletions

diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index bc8e80a86bca..08f4eb2763d1 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 */