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trace_selftest.c
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// SPDX-License-Identifier: GPL-2.0
/* Include in trace.c */
#include <uapi/linux/sched/types.h>
#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)
{
switch (entry->type) {
case TRACE_FN:
case TRACE_CTX:
case TRACE_WAKE:
case TRACE_STACK:
case TRACE_PRINT:
case TRACE_BRANCH:
case TRACE_GRAPH_ENT:
case TRACE_GRAPH_RETADDR_ENT:
case TRACE_GRAPH_RET:
return 1;
}
return 0;
}
static int trace_test_buffer_cpu(struct array_buffer *buf, int cpu)
{
struct ring_buffer_event *event;
struct trace_entry *entry;
unsigned int loops = 0;
while ((event = ring_buffer_consume(buf->buffer, cpu, NULL, NULL))) {
entry = ring_buffer_event_data(event);
/*
* 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;
}
if (!trace_valid_entry(entry)) {
printk(KERN_CONT ".. invalid entry %d ",
entry->type);
goto failed;
}
}
return 0;
failed:
/* disable tracing */
tracing_disabled = 1;
printk(KERN_CONT ".. corrupted trace buffer .. ");
return -1;
}
/*
* Test the trace buffer to see if all the elements
* are still sane.
*/
static int __maybe_unused trace_test_buffer(struct array_buffer *buf, unsigned long *count)
{
unsigned long flags, cnt = 0;
int cpu, ret = 0;
/* Don't allow flipping of max traces now */
local_irq_save(flags);
arch_spin_lock(&buf->tr->max_lock);
cnt = ring_buffer_entries(buf->buffer);
/*
* 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;
}
tracing_on();
arch_spin_unlock(&buf->tr->max_lock);
local_irq_restore(flags);
if (count)
*count = cnt;
return ret;
}
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
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 ftrace_regs *fregs)
{
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 ftrace_regs *fregs)
{
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 ftrace_regs *fregs)
{
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 ftrace_regs *fregs)
{
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 ftrace_regs *fregs)
{
trace_selftest_test_dyn_cnt++;
}
static struct ftrace_ops test_probe1 = {
.func = trace_selftest_test_probe1_func,
};
static struct ftrace_ops test_probe2 = {
.func = trace_selftest_test_probe2_func,
};
static struct ftrace_ops test_probe3 = {
.func = trace_selftest_test_probe3_func,
};
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_free;
}
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;
/* Remove trace function from probe 3 */
func1_name = "!" __stringify(DYN_FTRACE_TEST_NAME);
len1 = strlen(func1_name);
ftrace_set_filter(&test_probe3, func1_name, len1, 0);
DYN_FTRACE_TEST_NAME();
print_counts();
if (trace_selftest_test_probe1_cnt != 3)
goto out_free;
if (trace_selftest_test_probe2_cnt != 2)
goto out_free;
if (trace_selftest_test_probe3_cnt != 4)
goto out_free;
if (cnt > 1) {
if (trace_selftest_test_global_cnt == 0)
goto out_free;
}
if (trace_selftest_test_dyn_cnt == 0)
goto out_free;
DYN_FTRACE_TEST_NAME2();
print_counts();
if (trace_selftest_test_probe1_cnt != 3)
goto out_free;
if (trace_selftest_test_probe2_cnt != 3)
goto out_free;
if (trace_selftest_test_probe3_cnt != 5)
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 */
static int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
struct trace_array *tr,
int (*func)(void))
{
int save_ftrace_enabled = ftrace_enabled;
unsigned long count;
char *func_name;
int ret;
/* The ftrace test PASSED */
printk(KERN_CONT "PASSED\n");
pr_info("Testing dynamic ftrace: ");
/* enable tracing, and record the filter function */
ftrace_enabled = 1;
/* passed in by parameter to fool gcc from optimizing */
func();
/*
* Some archs *cough*PowerPC*cough* add characters to the
* start of the function names. We simply put a '*' to
* accommodate them.
*/
func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
/* filter only on our function */
ftrace_set_global_filter(func_name, strlen(func_name), 1);
/* enable tracing */
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->array_buffer, &count);
if (ret)
goto out;
if (count) {
ret = -1;
printk(KERN_CONT ".. filter did not filter .. ");
goto out;
}
/* call our function again */
func();
/* sleep again */
msleep(100);
/* stop the tracing. */
tracing_stop();
ftrace_enabled = 0;
/* check the trace buffer */
ret = trace_test_buffer(&tr->array_buffer, &count);
ftrace_enabled = 1;
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;
/* Enable tracing on all functions again */
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 ftrace_regs *fregs)
{
/*
* 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 ftrace_regs *fregs)
{
/*
* 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,
.flags = FTRACE_OPS_FL_RECURSION,
};
static struct ftrace_ops test_recsafe_probe = {
.func = trace_selftest_test_recursion_safe_func,
};
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;
/*
* Recursion allows for transitions between context,
* and may call the callback twice.
*/
if (trace_selftest_recursion_cnt != 1 &&
trace_selftest_recursion_cnt != 2) {
pr_cont("*callback not called once (or twice) (%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 ftrace_regs *fregs)
{
struct pt_regs *regs = ftrace_get_regs(fregs);
if (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_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.
*/
__init int
trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
{
int save_ftrace_enabled = ftrace_enabled;
unsigned long count;
int ret;
#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);
/* start the tracing */
ftrace_enabled = 1;
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. */
tracing_stop();
ftrace_enabled = 0;
/* check the trace buffer */
ret = trace_test_buffer(&tr->array_buffer, &count);
ftrace_enabled = 1;
trace->reset(tr);
tracing_start();
if (!ret && !count) {
printk(KERN_CONT ".. no entries found ..");
ret = -1;
goto out;
}
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;
/* kill ftrace totally if we failed */
if (ret)
ftrace_kill();
return ret;
}
#endif /* CONFIG_FUNCTION_TRACER */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
#ifdef CONFIG_DYNAMIC_FTRACE
#define CHAR_NUMBER 123
#define SHORT_NUMBER 12345
#define WORD_NUMBER 1234567890
#define LONG_NUMBER 1234567890123456789LL
#define ERRSTR_BUFLEN 128
struct fgraph_fixture {
struct fgraph_ops gops;
int store_size;
const char *store_type_name;
char error_str_buf[ERRSTR_BUFLEN];
char *error_str;
};
static __init int store_entry(struct ftrace_graph_ent *trace,
struct fgraph_ops *gops)
{
struct fgraph_fixture *fixture = container_of(gops, struct fgraph_fixture, gops);
const char *type = fixture->store_type_name;
int size = fixture->store_size;
void *p;
p = fgraph_reserve_data(gops->idx, size);
if (!p) {
snprintf(fixture->error_str_buf, ERRSTR_BUFLEN,
"Failed to reserve %s\n", type);
return 0;
}
switch (size) {
case 1:
*(char *)p = CHAR_NUMBER;
break;
case 2:
*(short *)p = SHORT_NUMBER;
break;
case 4:
*(int *)p = WORD_NUMBER;
break;
case 8:
*(long long *)p = LONG_NUMBER;
break;
}
return 1;
}
static __init void store_return(struct ftrace_graph_ret *trace,
struct fgraph_ops *gops)
{
struct fgraph_fixture *fixture = container_of(gops, struct fgraph_fixture, gops);
const char *type = fixture->store_type_name;
long long expect = 0;
long long found = -1;
int size;
char *p;
p = fgraph_retrieve_data(gops->idx, &size);
if (!p) {
snprintf(fixture->error_str_buf, ERRSTR_BUFLEN,
"Failed to retrieve %s\n", type);
return;
}
if (fixture->store_size > size) {
snprintf(fixture->error_str_buf, ERRSTR_BUFLEN,
"Retrieved size %d is smaller than expected %d\n",
size, (int)fixture->store_size);
return;
}
switch (fixture->store_size) {
case 1:
expect = CHAR_NUMBER;
found = *(char *)p;
break;
case 2:
expect = SHORT_NUMBER;
found = *(short *)p;
break;
case 4:
expect = WORD_NUMBER;
found = *(int *)p;
break;
case 8:
expect = LONG_NUMBER;
found = *(long long *)p;
break;
}
if (found != expect) {
snprintf(fixture->error_str_buf, ERRSTR_BUFLEN,
"%s returned not %lld but %lld\n", type, expect, found);
return;
}
fixture->error_str = NULL;
}
static int __init init_fgraph_fixture(struct fgraph_fixture *fixture)
{
char *func_name;
int len;
snprintf(fixture->error_str_buf, ERRSTR_BUFLEN,
"Failed to execute storage %s\n", fixture->store_type_name);
fixture->error_str = fixture->error_str_buf;
func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
len = strlen(func_name);
return ftrace_set_filter(&fixture->gops.ops, func_name, len, 1);
}
/* Test fgraph storage for each size */
static int __init test_graph_storage_single(struct fgraph_fixture *fixture)
{
int size = fixture->store_size;
int ret;
pr_cont("PASSED\n");
pr_info("Testing fgraph storage of %d byte%s: ", size, str_plural(size));
ret = init_fgraph_fixture(fixture);
if (ret && ret != -ENODEV) {
pr_cont("*Could not set filter* ");
return -1;
}
ret = register_ftrace_graph(&fixture->gops);
if (ret) {
pr_warn("Failed to init store_bytes fgraph tracing\n");
return -1;
}
DYN_FTRACE_TEST_NAME();
unregister_ftrace_graph(&fixture->gops);
if (fixture->error_str) {
pr_cont("*** %s ***", fixture->error_str);
return -1;
}
return 0;
}
static struct fgraph_fixture store_bytes[4] __initdata = {
[0] = {
.gops = {
.entryfunc = store_entry,
.retfunc = store_return,
},
.store_size = 1,
.store_type_name = "byte",
},
[1] = {
.gops = {
.entryfunc = store_entry,
.retfunc = store_return,
},
.store_size = 2,
.store_type_name = "short",
},
[2] = {
.gops = {
.entryfunc = store_entry,
.retfunc = store_return,
},
.store_size = 4,
.store_type_name = "word",
},
[3] = {
.gops = {
.entryfunc = store_entry,
.retfunc = store_return,
},
.store_size = 8,
.store_type_name = "long long",
},
};
static __init int test_graph_storage_multi(void)
{
struct fgraph_fixture *fixture;
bool printed = false;
int i, j, ret;
pr_cont("PASSED\n");
pr_info("Testing multiple fgraph storage on a function: ");
for (i = 0; i < ARRAY_SIZE(store_bytes); i++) {
fixture = &store_bytes[i];
ret = init_fgraph_fixture(fixture);
if (ret && ret != -ENODEV) {
pr_cont("*Could not set filter* ");
printed = true;
goto out2;
}
}
for (j = 0; j < ARRAY_SIZE(store_bytes); j++) {
fixture = &store_bytes[j];
ret = register_ftrace_graph(&fixture->gops);
if (ret) {
pr_warn("Failed to init store_bytes fgraph tracing\n");
printed = true;
goto out1;
}
}
DYN_FTRACE_TEST_NAME();
out1:
while (--j >= 0) {
fixture = &store_bytes[j];
unregister_ftrace_graph(&fixture->gops);
if (fixture->error_str && !printed) {
pr_cont("*** %s ***", fixture->error_str);
printed = true;
}
}
out2:
while (--i >= 0) {
fixture = &store_bytes[i];
ftrace_free_filter(&fixture->gops.ops);
if (fixture->error_str && !printed) {
pr_cont("*** %s ***", fixture->error_str);
printed = true;
}
}
return printed ? -1 : 0;
}
/* Test the storage passed across function_graph entry and return */
static __init int test_graph_storage(void)
{
int ret;
ret = test_graph_storage_single(&store_bytes[0]);