aboutsummaryrefslogtreecommitdiff
path: root/kernel/trace/trace_selftest.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/trace/trace_selftest.c')
-rw-r--r--kernel/trace/trace_selftest.c1003
1 files changed, 819 insertions, 184 deletions
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 0911b7e073b..5ef60499dc8 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -1,7 +1,9 @@
/* Include in trace.c */
+#include <linux/stringify.h>
#include <linux/kthread.h>
#include <linux/delay.h>
+#include <linux/slab.h>
static inline int trace_valid_entry(struct trace_entry *entry)
{
@@ -10,64 +12,39 @@ static inline int trace_valid_entry(struct trace_entry *entry)
case TRACE_CTX:
case TRACE_WAKE:
case TRACE_STACK:
- case TRACE_SPECIAL:
+ case TRACE_PRINT:
+ case TRACE_BRANCH:
+ case TRACE_GRAPH_ENT:
+ case TRACE_GRAPH_RET:
return 1;
}
return 0;
}
-static int
-trace_test_buffer_cpu(struct trace_array *tr, struct trace_array_cpu *data)
+static int trace_test_buffer_cpu(struct trace_buffer *buf, int cpu)
{
- struct trace_entry *entries;
- struct page *page;
- int idx = 0;
- int i;
-
- BUG_ON(list_empty(&data->trace_pages));
- page = list_entry(data->trace_pages.next, struct page, lru);
- entries = page_address(page);
-
- check_pages(data);
- if (head_page(data) != entries)
- goto failed;
-
- /*
- * The starting trace buffer always has valid elements,
- * if any element exists.
- */
- entries = head_page(data);
+ struct ring_buffer_event *event;
+ struct trace_entry *entry;
+ unsigned int loops = 0;
- for (i = 0; i < tr->entries; i++) {
+ while ((event = ring_buffer_consume(buf->buffer, cpu, NULL, NULL))) {
+ entry = ring_buffer_event_data(event);
- if (i < data->trace_idx && !trace_valid_entry(&entries[idx])) {
- printk(KERN_CONT ".. invalid entry %d ",
- entries[idx].type);
+ /*
+ * The ring buffer is a size of trace_buf_size, if
+ * we loop more than the size, there's something wrong
+ * with the ring buffer.
+ */
+ if (loops++ > trace_buf_size) {
+ printk(KERN_CONT ".. bad ring buffer ");
goto failed;
}
-
- idx++;
- if (idx >= ENTRIES_PER_PAGE) {
- page = virt_to_page(entries);
- if (page->lru.next == &data->trace_pages) {
- if (i != tr->entries - 1) {
- printk(KERN_CONT ".. entries buffer mismatch");
- goto failed;
- }
- } else {
- page = list_entry(page->lru.next, struct page, lru);
- entries = page_address(page);
- }
- idx = 0;
+ if (!trace_valid_entry(entry)) {
+ printk(KERN_CONT ".. invalid entry %d ",
+ entry->type);
+ goto failed;
}
}
-
- page = virt_to_page(entries);
- if (page->lru.next != &data->trace_pages) {
- printk(KERN_CONT ".. too many entries");
- goto failed;
- }
-
return 0;
failed:
@@ -81,26 +58,33 @@ trace_test_buffer_cpu(struct trace_array *tr, struct trace_array_cpu *data)
* Test the trace buffer to see if all the elements
* are still sane.
*/
-static int trace_test_buffer(struct trace_array *tr, unsigned long *count)
+static int trace_test_buffer(struct trace_buffer *buf, unsigned long *count)
{
unsigned long flags, cnt = 0;
int cpu, ret = 0;
/* Don't allow flipping of max traces now */
- raw_local_irq_save(flags);
- __raw_spin_lock(&ftrace_max_lock);
- for_each_possible_cpu(cpu) {
- if (!head_page(tr->data[cpu]))
- continue;
+ local_irq_save(flags);
+ arch_spin_lock(&buf->tr->max_lock);
- cnt += tr->data[cpu]->trace_idx;
+ cnt = ring_buffer_entries(buf->buffer);
- ret = trace_test_buffer_cpu(tr, tr->data[cpu]);
+ /*
+ * The trace_test_buffer_cpu runs a while loop to consume all data.
+ * If the calling tracer is broken, and is constantly filling
+ * the buffer, this will run forever, and hard lock the box.
+ * We disable the ring buffer while we do this test to prevent
+ * a hard lock up.
+ */
+ tracing_off();
+ for_each_possible_cpu(cpu) {
+ ret = trace_test_buffer_cpu(buf, cpu);
if (ret)
break;
}
- __raw_spin_unlock(&ftrace_max_lock);
- raw_local_irq_restore(flags);
+ tracing_on();
+ arch_spin_unlock(&buf->tr->max_lock);
+ local_irq_restore(flags);
if (count)
*count = cnt;
@@ -108,23 +92,242 @@ static int trace_test_buffer(struct trace_array *tr, unsigned long *count)
return ret;
}
-#ifdef CONFIG_FTRACE
+static inline void warn_failed_init_tracer(struct tracer *trace, int init_ret)
+{
+ printk(KERN_WARNING "Failed to init %s tracer, init returned %d\n",
+ trace->name, init_ret);
+}
+#ifdef CONFIG_FUNCTION_TRACER
#ifdef CONFIG_DYNAMIC_FTRACE
-#define __STR(x) #x
-#define STR(x) __STR(x)
+static int trace_selftest_test_probe1_cnt;
+static void trace_selftest_test_probe1_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ trace_selftest_test_probe1_cnt++;
+}
+
+static int trace_selftest_test_probe2_cnt;
+static void trace_selftest_test_probe2_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ trace_selftest_test_probe2_cnt++;
+}
+
+static int trace_selftest_test_probe3_cnt;
+static void trace_selftest_test_probe3_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ trace_selftest_test_probe3_cnt++;
+}
+
+static int trace_selftest_test_global_cnt;
+static void trace_selftest_test_global_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ trace_selftest_test_global_cnt++;
+}
+
+static int trace_selftest_test_dyn_cnt;
+static void trace_selftest_test_dyn_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ trace_selftest_test_dyn_cnt++;
+}
+
+static struct ftrace_ops test_probe1 = {
+ .func = trace_selftest_test_probe1_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+};
+
+static struct ftrace_ops test_probe2 = {
+ .func = trace_selftest_test_probe2_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+};
+
+static struct ftrace_ops test_probe3 = {
+ .func = trace_selftest_test_probe3_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+};
+
+static void print_counts(void)
+{
+ printk("(%d %d %d %d %d) ",
+ trace_selftest_test_probe1_cnt,
+ trace_selftest_test_probe2_cnt,
+ trace_selftest_test_probe3_cnt,
+ trace_selftest_test_global_cnt,
+ trace_selftest_test_dyn_cnt);
+}
+
+static void reset_counts(void)
+{
+ trace_selftest_test_probe1_cnt = 0;
+ trace_selftest_test_probe2_cnt = 0;
+ trace_selftest_test_probe3_cnt = 0;
+ trace_selftest_test_global_cnt = 0;
+ trace_selftest_test_dyn_cnt = 0;
+}
+
+static int trace_selftest_ops(struct trace_array *tr, int cnt)
+{
+ int save_ftrace_enabled = ftrace_enabled;
+ struct ftrace_ops *dyn_ops;
+ char *func1_name;
+ char *func2_name;
+ int len1;
+ int len2;
+ int ret = -1;
+
+ printk(KERN_CONT "PASSED\n");
+ pr_info("Testing dynamic ftrace ops #%d: ", cnt);
+
+ ftrace_enabled = 1;
+ reset_counts();
+
+ /* Handle PPC64 '.' name */
+ func1_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
+ func2_name = "*" __stringify(DYN_FTRACE_TEST_NAME2);
+ len1 = strlen(func1_name);
+ len2 = strlen(func2_name);
+
+ /*
+ * Probe 1 will trace function 1.
+ * Probe 2 will trace function 2.
+ * Probe 3 will trace functions 1 and 2.
+ */
+ ftrace_set_filter(&test_probe1, func1_name, len1, 1);
+ ftrace_set_filter(&test_probe2, func2_name, len2, 1);
+ ftrace_set_filter(&test_probe3, func1_name, len1, 1);
+ ftrace_set_filter(&test_probe3, func2_name, len2, 0);
+
+ register_ftrace_function(&test_probe1);
+ register_ftrace_function(&test_probe2);
+ register_ftrace_function(&test_probe3);
+ /* First time we are running with main function */
+ if (cnt > 1) {
+ ftrace_init_array_ops(tr, trace_selftest_test_global_func);
+ register_ftrace_function(tr->ops);
+ }
+
+ DYN_FTRACE_TEST_NAME();
+
+ print_counts();
+
+ if (trace_selftest_test_probe1_cnt != 1)
+ goto out;
+ if (trace_selftest_test_probe2_cnt != 0)
+ goto out;
+ if (trace_selftest_test_probe3_cnt != 1)
+ goto out;
+ if (cnt > 1) {
+ if (trace_selftest_test_global_cnt == 0)
+ goto out;
+ }
+
+ DYN_FTRACE_TEST_NAME2();
+
+ print_counts();
+
+ if (trace_selftest_test_probe1_cnt != 1)
+ goto out;
+ if (trace_selftest_test_probe2_cnt != 1)
+ goto out;
+ if (trace_selftest_test_probe3_cnt != 2)
+ goto out;
+
+ /* Add a dynamic probe */
+ dyn_ops = kzalloc(sizeof(*dyn_ops), GFP_KERNEL);
+ if (!dyn_ops) {
+ printk("MEMORY ERROR ");
+ goto out;
+ }
+
+ dyn_ops->func = trace_selftest_test_dyn_func;
+
+ register_ftrace_function(dyn_ops);
+
+ trace_selftest_test_global_cnt = 0;
+
+ DYN_FTRACE_TEST_NAME();
+
+ print_counts();
+
+ if (trace_selftest_test_probe1_cnt != 2)
+ goto out_free;
+ if (trace_selftest_test_probe2_cnt != 1)
+ goto out_free;
+ if (trace_selftest_test_probe3_cnt != 3)
+ goto out_free;
+ if (cnt > 1) {
+ if (trace_selftest_test_global_cnt == 0)
+ goto out;
+ }
+ if (trace_selftest_test_dyn_cnt == 0)
+ goto out_free;
+
+ DYN_FTRACE_TEST_NAME2();
+
+ print_counts();
+
+ if (trace_selftest_test_probe1_cnt != 2)
+ goto out_free;
+ if (trace_selftest_test_probe2_cnt != 2)
+ goto out_free;
+ if (trace_selftest_test_probe3_cnt != 4)
+ goto out_free;
+
+ ret = 0;
+ out_free:
+ unregister_ftrace_function(dyn_ops);
+ kfree(dyn_ops);
+
+ out:
+ /* Purposely unregister in the same order */
+ unregister_ftrace_function(&test_probe1);
+ unregister_ftrace_function(&test_probe2);
+ unregister_ftrace_function(&test_probe3);
+ if (cnt > 1)
+ unregister_ftrace_function(tr->ops);
+ ftrace_reset_array_ops(tr);
+
+ /* Make sure everything is off */
+ reset_counts();
+ DYN_FTRACE_TEST_NAME();
+ DYN_FTRACE_TEST_NAME();
+
+ if (trace_selftest_test_probe1_cnt ||
+ trace_selftest_test_probe2_cnt ||
+ trace_selftest_test_probe3_cnt ||
+ trace_selftest_test_global_cnt ||
+ trace_selftest_test_dyn_cnt)
+ ret = -1;
+
+ ftrace_enabled = save_ftrace_enabled;
+
+ return ret;
+}
/* Test dynamic code modification and ftrace filters */
-int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
- struct trace_array *tr,
- int (*func)(void))
+static int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
+ struct trace_array *tr,
+ int (*func)(void))
{
- unsigned long count;
- int ret;
int save_ftrace_enabled = ftrace_enabled;
- int save_tracer_enabled = tracer_enabled;
+ unsigned long count;
char *func_name;
+ int ret;
/* The ftrace test PASSED */
printk(KERN_CONT "PASSED\n");
@@ -132,36 +335,32 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
/* enable tracing, and record the filter function */
ftrace_enabled = 1;
- tracer_enabled = 1;
/* passed in by parameter to fool gcc from optimizing */
func();
- /* update the records */
- ret = ftrace_force_update();
- if (ret) {
- printk(KERN_CONT ".. ftraced failed .. ");
- return ret;
- }
-
/*
- * 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);
+ ftrace_set_global_filter(func_name, strlen(func_name), 1);
/* enable tracing */
- tr->ctrl = 1;
- trace->init(tr);
+ ret = tracer_init(trace, tr);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ goto out;
+ }
+
/* Sleep for a 1/10 of a second */
msleep(100);
/* we should have nothing in the buffer */
- ret = trace_test_buffer(tr, &count);
+ ret = trace_test_buffer(&tr->trace_buffer, &count);
if (ret)
goto out;
@@ -178,71 +377,310 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
msleep(100);
/* stop the tracing. */
- tr->ctrl = 0;
- trace->ctrl_update(tr);
+ tracing_stop();
ftrace_enabled = 0;
/* check the trace buffer */
- ret = trace_test_buffer(tr, &count);
- trace->reset(tr);
+ ret = trace_test_buffer(&tr->trace_buffer, &count);
+ tracing_start();
/* we should only have one item */
if (!ret && count != 1) {
+ trace->reset(tr);
printk(KERN_CONT ".. filter failed count=%ld ..", count);
ret = -1;
goto out;
}
+
+ /* Test the ops with global tracing running */
+ ret = trace_selftest_ops(tr, 1);
+ trace->reset(tr);
+
out:
ftrace_enabled = save_ftrace_enabled;
- tracer_enabled = save_tracer_enabled;
/* Enable tracing on all functions again */
- ftrace_set_filter(NULL, 0, 1);
+ ftrace_set_global_filter(NULL, 0, 1);
+
+ /* Test the ops with global tracing off */
+ if (!ret)
+ ret = trace_selftest_ops(tr, 2);
+
+ return ret;
+}
+
+static int trace_selftest_recursion_cnt;
+static void trace_selftest_test_recursion_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ /*
+ * This function is registered without the recursion safe flag.
+ * The ftrace infrastructure should provide the recursion
+ * protection. If not, this will crash the kernel!
+ */
+ if (trace_selftest_recursion_cnt++ > 10)
+ return;
+ DYN_FTRACE_TEST_NAME();
+}
+
+static void trace_selftest_test_recursion_safe_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ /*
+ * We said we would provide our own recursion. By calling
+ * this function again, we should recurse back into this function
+ * and count again. But this only happens if the arch supports
+ * all of ftrace features and nothing else is using the function
+ * tracing utility.
+ */
+ if (trace_selftest_recursion_cnt++)
+ return;
+ DYN_FTRACE_TEST_NAME();
+}
+
+static struct ftrace_ops test_rec_probe = {
+ .func = trace_selftest_test_recursion_func,
+};
+
+static struct ftrace_ops test_recsafe_probe = {
+ .func = trace_selftest_test_recursion_safe_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+};
+
+static int
+trace_selftest_function_recursion(void)
+{
+ int save_ftrace_enabled = ftrace_enabled;
+ char *func_name;
+ int len;
+ int ret;
+
+ /* The previous test PASSED */
+ pr_cont("PASSED\n");
+ pr_info("Testing ftrace recursion: ");
+
+
+ /* enable tracing, and record the filter function */
+ ftrace_enabled = 1;
+
+ /* Handle PPC64 '.' name */
+ func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
+ len = strlen(func_name);
+
+ ret = ftrace_set_filter(&test_rec_probe, func_name, len, 1);
+ if (ret) {
+ pr_cont("*Could not set filter* ");
+ goto out;
+ }
+
+ ret = register_ftrace_function(&test_rec_probe);
+ if (ret) {
+ pr_cont("*could not register callback* ");
+ goto out;
+ }
+
+ DYN_FTRACE_TEST_NAME();
+
+ unregister_ftrace_function(&test_rec_probe);
+
+ ret = -1;
+ if (trace_selftest_recursion_cnt != 1) {
+ pr_cont("*callback not called once (%d)* ",
+ trace_selftest_recursion_cnt);
+ goto out;
+ }
+
+ trace_selftest_recursion_cnt = 1;
+
+ pr_cont("PASSED\n");
+ pr_info("Testing ftrace recursion safe: ");
+
+ ret = ftrace_set_filter(&test_recsafe_probe, func_name, len, 1);
+ if (ret) {
+ pr_cont("*Could not set filter* ");
+ goto out;
+ }
+
+ ret = register_ftrace_function(&test_recsafe_probe);
+ if (ret) {
+ pr_cont("*could not register callback* ");
+ goto out;
+ }
+
+ DYN_FTRACE_TEST_NAME();
+
+ unregister_ftrace_function(&test_recsafe_probe);
+
+ ret = -1;
+ if (trace_selftest_recursion_cnt != 2) {
+ pr_cont("*callback not called expected 2 times (%d)* ",
+ trace_selftest_recursion_cnt);
+ goto out;
+ }
+
+ ret = 0;
+out:
+ ftrace_enabled = save_ftrace_enabled;
return ret;
}
#else
# define trace_selftest_startup_dynamic_tracing(trace, tr, func) ({ 0; })
+# define trace_selftest_function_recursion() ({ 0; })
#endif /* CONFIG_DYNAMIC_FTRACE */
+
+static enum {
+ TRACE_SELFTEST_REGS_START,
+ TRACE_SELFTEST_REGS_FOUND,
+ TRACE_SELFTEST_REGS_NOT_FOUND,
+} trace_selftest_regs_stat;
+
+static void trace_selftest_test_regs_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ if (pt_regs)
+ trace_selftest_regs_stat = TRACE_SELFTEST_REGS_FOUND;
+ else
+ trace_selftest_regs_stat = TRACE_SELFTEST_REGS_NOT_FOUND;
+}
+
+static struct ftrace_ops test_regs_probe = {
+ .func = trace_selftest_test_regs_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_SAVE_REGS,
+};
+
+static int
+trace_selftest_function_regs(void)
+{
+ int save_ftrace_enabled = ftrace_enabled;
+ char *func_name;
+ int len;
+ int ret;
+ int supported = 0;
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+ supported = 1;
+#endif
+
+ /* The previous test PASSED */
+ pr_cont("PASSED\n");
+ pr_info("Testing ftrace regs%s: ",
+ !supported ? "(no arch support)" : "");
+
+ /* enable tracing, and record the filter function */
+ ftrace_enabled = 1;
+
+ /* Handle PPC64 '.' name */
+ func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
+ len = strlen(func_name);
+
+ ret = ftrace_set_filter(&test_regs_probe, func_name, len, 1);
+ /*
+ * If DYNAMIC_FTRACE is not set, then we just trace all functions.
+ * This test really doesn't care.
+ */
+ if (ret && ret != -ENODEV) {
+ pr_cont("*Could not set filter* ");
+ goto out;
+ }
+
+ ret = register_ftrace_function(&test_regs_probe);
+ /*
+ * Now if the arch does not support passing regs, then this should
+ * have failed.
+ */
+ if (!supported) {
+ if (!ret) {
+ pr_cont("*registered save-regs without arch support* ");
+ goto out;
+ }
+ test_regs_probe.flags |= FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED;
+ ret = register_ftrace_function(&test_regs_probe);
+ }
+ if (ret) {
+ pr_cont("*could not register callback* ");
+ goto out;
+ }
+
+
+ DYN_FTRACE_TEST_NAME();
+
+ unregister_ftrace_function(&test_regs_probe);
+
+ ret = -1;
+
+ switch (trace_selftest_regs_stat) {
+ case TRACE_SELFTEST_REGS_START:
+ pr_cont("*callback never called* ");
+ goto out;
+
+ case TRACE_SELFTEST_REGS_FOUND:
+ if (supported)
+ break;
+ pr_cont("*callback received regs without arch support* ");
+ goto out;
+
+ case TRACE_SELFTEST_REGS_NOT_FOUND:
+ if (!supported)
+ break;
+ pr_cont("*callback received NULL regs* ");
+ goto out;
+ }
+
+ ret = 0;
+out:
+ ftrace_enabled = save_ftrace_enabled;
+
+ return ret;
+}
+
/*
* Simple verification test of ftrace function tracer.
* Enable ftrace, sleep 1/10 second, and then read the trace
* buffer to see if all is in order.
*/
-int
+__init int
trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
{
+ int save_ftrace_enabled = ftrace_enabled;
unsigned long count;
int ret;
- int save_ftrace_enabled = ftrace_enabled;
- int save_tracer_enabled = tracer_enabled;
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+ if (ftrace_filter_param) {
+ printk(KERN_CONT " ... kernel command line filter set: force PASS ... ");
+ return 0;
+ }
+#endif
/* make sure msleep has been recorded */
msleep(1);
- /* force the recorded functions to be traced */
- ret = ftrace_force_update();
- if (ret) {
- printk(KERN_CONT ".. ftraced failed .. ");
- return ret;
- }
-
/* start the tracing */
ftrace_enabled = 1;
- tracer_enabled = 1;
- tr->ctrl = 1;
- trace->init(tr);
+ ret = tracer_init(trace, tr);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ goto out;
+ }
+
/* Sleep for a 1/10 of a second */
msleep(100);
/* stop the tracing. */
- tr->ctrl = 0;
- trace->ctrl_update(tr);
+ tracing_stop();
ftrace_enabled = 0;
/* check the trace buffer */
- ret = trace_test_buffer(tr, &count);
+ ret = trace_test_buffer(&tr->trace_buffer, &count);
trace->reset(tr);
+ tracing_start();
if (!ret && !count) {
printk(KERN_CONT ".. no entries found ..");
@@ -252,10 +690,16 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
ret = trace_selftest_startup_dynamic_tracing(trace, tr,
DYN_FTRACE_TEST_NAME);
+ if (ret)
+ goto out;
+ ret = trace_selftest_function_recursion();
+ if (ret)
+ goto out;
+
+ ret = trace_selftest_function_regs();
out:
ftrace_enabled = save_ftrace_enabled;
- tracer_enabled = save_tracer_enabled;
/* kill ftrace totally if we failed */
if (ret)
@@ -263,40 +707,146 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
return ret;
}
-#endif /* CONFIG_FTRACE */
+#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 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(DUMP_ALL);
+ /* ftrace_dump() disables tracing */
+ tracing_on();
+ }
+ return 0;
+ }
+
+ return trace_graph_entry(trace);
+}
+
+/*
+ * Pretty much the same than for the function tracer from which the selftest
+ * has been borrowed.
+ */
+__init int
+trace_selftest_startup_function_graph(struct tracer *trace,
+ struct trace_array *tr)
+{
+ int ret;
+ unsigned long count;
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+ if (ftrace_filter_param) {
+ printk(KERN_CONT " ... kernel command line filter set: force PASS ... ");
+ return 0;
+ }
+#endif
+
+ /*
+ * Simulate the init() callback but we attach a watchdog callback
+ * to detect and recover from possible hangs
+ */
+ tracing_reset_online_cpus(&tr->trace_buffer);
+ set_graph_array(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->trace_buffer, &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)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
unsigned long count;
int ret;
/* start the tracing */
- tr->ctrl = 1;
- trace->init(tr);
+ ret = tracer_init(trace, tr);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ return ret;
+ }
+
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
/* disable interrupts for a bit */
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. */
- tr->ctrl = 0;
- trace->ctrl_update(tr);
+ tracing_stop();
/* check both trace buffers */
- ret = trace_test_buffer(tr, NULL);
+ ret = trace_test_buffer(&tr->trace_buffer, NULL);
if (!ret)
- ret = trace_test_buffer(&max_tr, &count);
+ ret = trace_test_buffer(&tr->max_buffer, &count);
trace->reset(tr);
+ tracing_start();
if (!ret && !count) {
printk(KERN_CONT ".. no entries found ..");
ret = -1;
}
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
return ret;
}
@@ -306,34 +856,59 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
int
trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
unsigned long count;
int ret;
+ /*
+ * Now that the big kernel lock is no longer preemptable,
+ * and this is called with the BKL held, it will always
+ * fail. If preemption is already disabled, simply
+ * pass the test. When the BKL is removed, or becomes
+ * preemptible again, we will once again test this,
+ * so keep it in.
+ */
+ if (preempt_count()) {
+ printk(KERN_CONT "can not test ... force ");
+ return 0;
+ }
+
/* start the tracing */
- tr->ctrl = 1;
- trace->init(tr);
+ ret = tracer_init(trace, tr);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ return ret;
+ }
+
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
/* disable preemption for a bit */
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. */
- tr->ctrl = 0;
- trace->ctrl_update(tr);
+ tracing_stop();
/* check both trace buffers */
- ret = trace_test_buffer(tr, NULL);
+ ret = trace_test_buffer(&tr->trace_buffer, NULL);
if (!ret)
- ret = trace_test_buffer(&max_tr, &count);
+ ret = trace_test_buffer(&tr->max_buffer, &count);
trace->reset(tr);
+ tracing_start();
if (!ret && !count) {
printk(KERN_CONT ".. no entries found ..");
ret = -1;
}
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
return ret;
}
@@ -343,16 +918,32 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
int
trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
unsigned long count;
int ret;
+ /*
+ * Now that the big kernel lock is no longer preemptable,
+ * and this is called with the BKL held, it will always
+ * fail. If preemption is already disabled, simply
+ * pass the test. When the BKL is removed, or becomes
+ * preemptible again, we will once again test this,
+ * so keep it in.
+ */
+ if (preempt_count()) {
+ printk(KERN_CONT "can not test ... force ");
+ return 0;
+ }
+
/* start the tracing */
- tr->ctrl = 1;
- trace->init(tr);
+ ret = tracer_init(trace, tr);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ goto out_no_start;
+ }
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
/* disable preemption and interrupts for a bit */
preempt_disable();
@@ -362,15 +953,21 @@ 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. */
- tr->ctrl = 0;
- trace->ctrl_update(tr);
+ tracing_stop();
/* check both trace buffers */
- ret = trace_test_buffer(tr, NULL);
+ ret = trace_test_buffer(&tr->trace_buffer, NULL);
if (ret)
goto out;
- ret = trace_test_buffer(&max_tr, &count);
+ ret = trace_test_buffer(&tr->max_buffer, &count);
if (ret)
goto out;
@@ -381,9 +978,10 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
}
/* do the test by disabling interrupts first this time */
- tracing_max_latency = 0;
- tr->ctrl = 1;
- trace->ctrl_update(tr);
+ tr->max_latency = 0;
+ tracing_start();
+ trace->start(tr);
+
preempt_disable();
local_irq_disable();
udelay(100);
@@ -391,15 +989,15 @@ 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. */
- tr->ctrl = 0;
- trace->ctrl_update(tr);
+ tracing_stop();
/* check both trace buffers */
- ret = trace_test_buffer(tr, NULL);
+ ret = trace_test_buffer(&tr->trace_buffer, NULL);
if (ret)
goto out;
- ret = trace_test_buffer(&max_tr, &count);
+ ret = trace_test_buffer(&tr->max_buffer, &count);
if (!ret && !count) {
printk(KERN_CONT ".. no entries found ..");
@@ -407,22 +1005,38 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
goto out;
}
- out:
+out:
+ tracing_start();
+out_no_start:
trace->reset(tr);
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
return ret;
}
#endif /* CONFIG_IRQSOFF_TRACER && CONFIG_PREEMPT_TRACER */
+#ifdef CONFIG_NOP_TRACER
+int
+trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr)
+{
+ /* What could possibly go wrong? */
+ return 0;
+}
+#endif
+
#ifdef CONFIG_SCHED_TRACER
static int trace_wakeup_test_thread(void *data)
{
- /* Make this a RT thread, doesn't need to be too high */
- struct sched_param param = { .sched_priority = 5 };
+ /* Make this a -deadline thread */
+ static const struct sched_attr attr = {
+ .sched_policy = SCHED_DEADLINE,
+ .sched_runtime = 100000ULL,
+ .sched_deadline = 10000000ULL,
+ .sched_period = 10000000ULL
+ };
struct completion *x = data;
- sched_setscheduler(current, SCHED_FIFO, &param);
+ sched_setattr(current, &attr);
/* Make it know we have a new prio */
complete(x);
@@ -431,11 +1045,13 @@ static int trace_wakeup_test_thread(void *data)
set_current_state(TASK_INTERRUPTIBLE);
schedule();
+ complete(x);
+
/* we are awake, now wait to disappear */
while (!kthread_should_stop()) {
/*
- * This is an RT task, do short sleeps to let
- * others run.
+ * This will likely be the system top priority
+ * task, do short sleeps to let others run.
*/
msleep(100);
}
@@ -446,58 +1062,63 @@ static int trace_wakeup_test_thread(void *data)
int
trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
struct task_struct *p;
- struct completion isrt;
+ struct completion is_ready;
unsigned long count;
int ret;
- init_completion(&isrt);
+ init_completion(&is_ready);
- /* create a high prio thread */
- p = kthread_run(trace_wakeup_test_thread, &isrt, "ftrace-test");
+ /* create a -deadline thread */
+ p = kthread_run(trace_wakeup_test_thread, &is_ready, "ftrace-test");
if (IS_ERR(p)) {
printk(KERN_CONT "Failed to create ftrace wakeup test thread ");
return -1;
}
- /* make sure the thread is running at an RT prio */
- wait_for_completion(&isrt);
+ /* make sure the thread is running at -deadline policy */
+ wait_for_completion(&is_ready);
/* start the tracing */
- tr->ctrl = 1;
- trace->init(tr);
+ ret = tracer_init(trace, tr);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ return ret;
+ }
+
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
- /* sleep to let the RT thread sleep too */
- msleep(100);
+ while (p->on_rq) {
+ /*
+ * Sleep to make sure the -deadline thread is asleep too.
+ * On virtual machines we can't rely on timings,
+ * but we want to make sure this test still works.
+ */
+ msleep(100);
+ }
- /*
- * Yes this is slightly racy. It is possible that for some
- * strange reason that the RT thread we created, did not
- * call schedule for 100ms after doing the completion,
- * and we do a wakeup on a task that already is awake.
- * But that is extremely unlikely, and the worst thing that
- * happens in such a case, is that we disable tracing.
- * Honestly, if this race does happen something is horrible
- * wrong with the system.
- */
+ init_completion(&is_ready);
wake_up_process(p);
+ /* Wait for the task to wake up */
+ wait_for_completion(&is_ready);
+
/* stop the tracing. */
- tr->ctrl = 0;
- trace->ctrl_update(tr);
+ tracing_stop();
/* check both trace buffers */
- ret = trace_test_buffer(tr, NULL);
+ ret = trace_test_buffer(&tr->trace_buffer, NULL);
+ printk("ret = %d\n", ret);
if (!ret)
- ret = trace_test_buffer(&max_tr, &count);
+ ret = trace_test_buffer(&tr->max_buffer, &count);
trace->reset(tr);
+ tracing_start();
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
/* kill the thread */
kthread_stop(p);
@@ -519,16 +1140,20 @@ trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr
int ret;
/* start the tracing */
- tr->ctrl = 1;
- trace->init(tr);
+ ret = tracer_init(trace, tr);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ return ret;
+ }
+
/* Sleep for a 1/10 of a second */
msleep(100);
/* stop the tracing. */
- tr->ctrl = 0;
- trace->ctrl_update(tr);
+ tracing_stop();
/* check the trace buffer */
- ret = trace_test_buffer(tr, &count);
+ ret = trace_test_buffer(&tr->trace_buffer, &count);
trace->reset(tr);
+ tracing_start();
if (!ret && !count) {
printk(KERN_CONT ".. no entries found ..");
@@ -539,25 +1164,35 @@ trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr
}
#endif /* CONFIG_CONTEXT_SWITCH_TRACER */
-#ifdef CONFIG_SYSPROF_TRACER
+#ifdef CONFIG_BRANCH_TRACER
int
-trace_selftest_startup_sysprof(struct tracer *trace, struct trace_array *tr)
+trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr)
{
unsigned long count;
int ret;
/* start the tracing */
- tr->ctrl = 1;
- trace->init(tr);
+ ret = tracer_init(trace, tr);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ return ret;
+ }
+
/* Sleep for a 1/10 of a second */
msleep(100);
/* stop the tracing. */
- tr->ctrl = 0;
- trace->ctrl_update(tr);
+ tracing_stop();
/* check the trace buffer */
- ret = trace_test_buffer(tr, &count);
+ ret = trace_test_buffer(&tr->trace_buffer, &count);
trace->reset(tr);
+ tracing_start();
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ }
return ret;
}
-#endif /* CONFIG_SYSPROF_TRACER */
+#endif /* CONFIG_BRANCH_TRACER */
+