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-rw-r--r--kernel/trace/fgraph.c33
-rw-r--r--kernel/trace/preemptirq_delay_test.c2
-rw-r--r--kernel/trace/ring_buffer.c12
-rw-r--r--kernel/trace/trace.c8
-rw-r--r--kernel/trace/trace.h23
-rw-r--r--kernel/trace/trace_events.c41
-rw-r--r--kernel/trace/trace_events_hist.c4
-rw-r--r--kernel/trace/trace_events_inject.c2
-rw-r--r--kernel/trace/trace_events_trigger.c6
-rw-r--r--kernel/trace/trace_osnoise.c54
-rw-r--r--kernel/trace/trace_selftest.c23
-rw-r--r--kernel/trace/tracing_map.c6
12 files changed, 132 insertions, 82 deletions
diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c
index fc205ad167a9..d7d4fb403f6f 100644
--- a/kernel/trace/fgraph.c
+++ b/kernel/trace/fgraph.c
@@ -902,7 +902,7 @@ unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx,
i = *idx ? : task->curr_ret_stack;
while (i > 0) {
- ret_stack = get_ret_stack(current, i, &i);
+ ret_stack = get_ret_stack(task, i, &i);
if (!ret_stack)
break;
/*
@@ -1206,18 +1206,24 @@ static void init_task_vars(int idx)
read_unlock(&tasklist_lock);
}
-static void ftrace_graph_enable_direct(bool enable_branch)
+static void ftrace_graph_enable_direct(bool enable_branch, struct fgraph_ops *gops)
{
trace_func_graph_ent_t func = NULL;
trace_func_graph_ret_t retfunc = NULL;
int i;
- for_each_set_bit(i, &fgraph_array_bitmask,
- sizeof(fgraph_array_bitmask) * BITS_PER_BYTE) {
- func = fgraph_array[i]->entryfunc;
- retfunc = fgraph_array[i]->retfunc;
- fgraph_direct_gops = fgraph_array[i];
- }
+ if (gops) {
+ func = gops->entryfunc;
+ retfunc = gops->retfunc;
+ fgraph_direct_gops = gops;
+ } else {
+ for_each_set_bit(i, &fgraph_array_bitmask,
+ sizeof(fgraph_array_bitmask) * BITS_PER_BYTE) {
+ func = fgraph_array[i]->entryfunc;
+ retfunc = fgraph_array[i]->retfunc;
+ fgraph_direct_gops = fgraph_array[i];
+ }
+ }
if (WARN_ON_ONCE(!func))
return;
@@ -1256,8 +1262,6 @@ int register_ftrace_graph(struct fgraph_ops *gops)
ret = -ENOSPC;
goto out;
}
-
- fgraph_array[i] = gops;
gops->idx = i;
ftrace_graph_active++;
@@ -1266,7 +1270,7 @@ int register_ftrace_graph(struct fgraph_ops *gops)
ftrace_graph_disable_direct(true);
if (ftrace_graph_active == 1) {
- ftrace_graph_enable_direct(false);
+ ftrace_graph_enable_direct(false, gops);
register_pm_notifier(&ftrace_suspend_notifier);
ret = start_graph_tracing();
if (ret)
@@ -1281,14 +1285,15 @@ int register_ftrace_graph(struct fgraph_ops *gops)
} else {
init_task_vars(gops->idx);
}
-
/* Always save the function, and reset at unregistering */
gops->saved_func = gops->entryfunc;
ret = ftrace_startup_subops(&graph_ops, &gops->ops, command);
+ if (!ret)
+ fgraph_array[i] = gops;
+
error:
if (ret) {
- fgraph_array[i] = &fgraph_stub;
ftrace_graph_active--;
gops->saved_func = NULL;
fgraph_lru_release_index(i);
@@ -1324,7 +1329,7 @@ void unregister_ftrace_graph(struct fgraph_ops *gops)
ftrace_shutdown_subops(&graph_ops, &gops->ops, command);
if (ftrace_graph_active == 1)
- ftrace_graph_enable_direct(true);
+ ftrace_graph_enable_direct(true, NULL);
else if (!ftrace_graph_active)
ftrace_graph_disable_direct(false);
diff --git a/kernel/trace/preemptirq_delay_test.c b/kernel/trace/preemptirq_delay_test.c
index cb0871fbdb07..314ffc143039 100644
--- a/kernel/trace/preemptirq_delay_test.c
+++ b/kernel/trace/preemptirq_delay_test.c
@@ -34,8 +34,6 @@ MODULE_PARM_DESC(cpu_affinity, "Cpu num test is running on");
static struct completion done;
-#define MIN(x, y) ((x) < (y) ? (x) : (y))
-
static void busy_wait(ulong time)
{
u64 start, end;
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 28853966aa9a..cebd879a30cb 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -693,18 +693,6 @@ u64 ring_buffer_event_time_stamp(struct trace_buffer *buffer,
}
/**
- * ring_buffer_nr_pages - get the number of buffer pages in the ring buffer
- * @buffer: The ring_buffer to get the number of pages from
- * @cpu: The cpu of the ring_buffer to get the number of pages from
- *
- * Returns the number of pages used by a per_cpu buffer of the ring buffer.
- */
-size_t ring_buffer_nr_pages(struct trace_buffer *buffer, int cpu)
-{
- return buffer->buffers[cpu]->nr_pages;
-}
-
-/**
* ring_buffer_nr_dirty_pages - get the number of used pages in the ring buffer
* @buffer: The ring_buffer to get the number of pages from
* @cpu: The cpu of the ring_buffer to get the number of pages from
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 10cd38bce2f1..c3b2c7dfadef 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2226,10 +2226,6 @@ static __init int init_trace_selftests(void)
}
core_initcall(init_trace_selftests);
#else
-static inline int run_tracer_selftest(struct tracer *type)
-{
- return 0;
-}
static inline int do_run_tracer_selftest(struct tracer *type)
{
return 0;
@@ -3958,6 +3954,8 @@ void tracing_iter_reset(struct trace_iterator *iter, int cpu)
break;
entries++;
ring_buffer_iter_advance(buf_iter);
+ /* This could be a big loop */
+ cond_resched();
}
per_cpu_ptr(iter->array_buffer->data, cpu)->skipped_entries = entries;
@@ -7956,7 +7954,7 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
trace_access_unlock(iter->cpu_file);
if (ret < 0) {
- if (trace_empty(iter)) {
+ if (trace_empty(iter) && !iter->closed) {
if ((filp->f_flags & O_NONBLOCK))
return -EAGAIN;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 8783bebd0562..bd3e3069300e 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1634,6 +1634,29 @@ static inline void *event_file_data(struct file *filp)
extern struct mutex event_mutex;
extern struct list_head ftrace_events;
+/*
+ * When the trace_event_file is the filp->i_private pointer,
+ * it must be taken under the event_mutex lock, and then checked
+ * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
+ * data pointed to by the trace_event_file can not be trusted.
+ *
+ * Use the event_file_file() to access the trace_event_file from
+ * the filp the first time under the event_mutex and check for
+ * NULL. If it is needed to be retrieved again and the event_mutex
+ * is still held, then the event_file_data() can be used and it
+ * is guaranteed to be valid.
+ */
+static inline struct trace_event_file *event_file_file(struct file *filp)
+{
+ struct trace_event_file *file;
+
+ lockdep_assert_held(&event_mutex);
+ file = READ_ONCE(file_inode(filp)->i_private);
+ if (!file || file->flags & EVENT_FILE_FL_FREED)
+ return NULL;
+ return file;
+}
+
extern const struct file_operations event_trigger_fops;
extern const struct file_operations event_hist_fops;
extern const struct file_operations event_hist_debug_fops;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 6ef29eba90ce..7266ec2a4eea 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -992,18 +992,18 @@ static void remove_subsystem(struct trace_subsystem_dir *dir)
void event_file_get(struct trace_event_file *file)
{
- atomic_inc(&file->ref);
+ refcount_inc(&file->ref);
}
void event_file_put(struct trace_event_file *file)
{
- if (WARN_ON_ONCE(!atomic_read(&file->ref))) {
+ if (WARN_ON_ONCE(!refcount_read(&file->ref))) {
if (file->flags & EVENT_FILE_FL_FREED)
kmem_cache_free(file_cachep, file);
return;
}
- if (atomic_dec_and_test(&file->ref)) {
+ if (refcount_dec_and_test(&file->ref)) {
/* Count should only go to zero when it is freed */
if (WARN_ON_ONCE(!(file->flags & EVENT_FILE_FL_FREED)))
return;
@@ -1386,12 +1386,12 @@ event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
char buf[4] = "0";
mutex_lock(&event_mutex);
- file = event_file_data(filp);
+ file = event_file_file(filp);
if (likely(file))
flags = file->flags;
mutex_unlock(&event_mutex);
- if (!file || flags & EVENT_FILE_FL_FREED)
+ if (!file)
return -ENODEV;
if (flags & EVENT_FILE_FL_ENABLED &&
@@ -1424,8 +1424,8 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
case 1:
ret = -ENODEV;
mutex_lock(&event_mutex);
- file = event_file_data(filp);
- if (likely(file && !(file->flags & EVENT_FILE_FL_FREED))) {
+ file = event_file_file(filp);
+ if (likely(file)) {
ret = tracing_update_buffers(file->tr);
if (ret < 0) {
mutex_unlock(&event_mutex);
@@ -1540,7 +1540,8 @@ enum {
static void *f_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct trace_event_call *call = event_file_data(m->private);
+ struct trace_event_file *file = event_file_data(m->private);
+ struct trace_event_call *call = file->event_call;
struct list_head *common_head = &ftrace_common_fields;
struct list_head *head = trace_get_fields(call);
struct list_head *node = v;
@@ -1572,7 +1573,8 @@ static void *f_next(struct seq_file *m, void *v, loff_t *pos)
static int f_show(struct seq_file *m, void *v)
{
- struct trace_event_call *call = event_file_data(m->private);
+ struct trace_event_file *file = event_file_data(m->private);
+ struct trace_event_call *call = file->event_call;
struct ftrace_event_field *field;
const char *array_descriptor;
@@ -1627,12 +1629,14 @@ static int f_show(struct seq_file *m, void *v)
static void *f_start(struct seq_file *m, loff_t *pos)
{
+ struct trace_event_file *file;
void *p = (void *)FORMAT_HEADER;
loff_t l = 0;
/* ->stop() is called even if ->start() fails */
mutex_lock(&event_mutex);
- if (!event_file_data(m->private))
+ file = event_file_file(m->private);
+ if (!file)
return ERR_PTR(-ENODEV);
while (l < *pos && p)
@@ -1706,8 +1710,8 @@ event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
trace_seq_init(s);
mutex_lock(&event_mutex);
- file = event_file_data(filp);
- if (file && !(file->flags & EVENT_FILE_FL_FREED))
+ file = event_file_file(filp);
+ if (file)
print_event_filter(file, s);
mutex_unlock(&event_mutex);
@@ -1736,9 +1740,13 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
return PTR_ERR(buf);
mutex_lock(&event_mutex);
- file = event_file_data(filp);
- if (file)
- err = apply_event_filter(file, buf);
+ file = event_file_file(filp);
+ if (file) {
+ if (file->flags & EVENT_FILE_FL_FREED)
+ err = -ENODEV;
+ else
+ err = apply_event_filter(file, buf);
+ }
mutex_unlock(&event_mutex);
kfree(buf);
@@ -2485,7 +2493,6 @@ static int event_callback(const char *name, umode_t *mode, void **data,
if (strcmp(name, "format") == 0) {
*mode = TRACE_MODE_READ;
*fops = &ftrace_event_format_fops;
- *data = call;
return 1;
}
@@ -2996,7 +3003,7 @@ trace_create_new_event(struct trace_event_call *call,
atomic_set(&file->tm_ref, 0);
INIT_LIST_HEAD(&file->triggers);
list_add(&file->list, &tr->events);
- event_file_get(file);
+ refcount_set(&file->ref, 1);
return file;
}
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 6ece1308d36a..5f9119eb7c67 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -5601,7 +5601,7 @@ static int hist_show(struct seq_file *m, void *v)
mutex_lock(&event_mutex);
- event_file = event_file_data(m->private);
+ event_file = event_file_file(m->private);
if (unlikely(!event_file)) {
ret = -ENODEV;
goto out_unlock;
@@ -5880,7 +5880,7 @@ static int hist_debug_show(struct seq_file *m, void *v)
mutex_lock(&event_mutex);
- event_file = event_file_data(m->private);
+ event_file = event_file_file(m->private);
if (unlikely(!event_file)) {
ret = -ENODEV;
goto out_unlock;
diff --git a/kernel/trace/trace_events_inject.c b/kernel/trace/trace_events_inject.c
index 8650562bdaa9..a8f076809db4 100644
--- a/kernel/trace/trace_events_inject.c
+++ b/kernel/trace/trace_events_inject.c
@@ -299,7 +299,7 @@ event_inject_write(struct file *filp, const char __user *ubuf, size_t cnt,
strim(buf);
mutex_lock(&event_mutex);
- file = event_file_data(filp);
+ file = event_file_file(filp);
if (file) {
call = file->event_call;
size = parse_entry(buf, call, &entry);
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 4bec043c8690..a5e3d6acf1e1 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -159,7 +159,7 @@ static void *trigger_start(struct seq_file *m, loff_t *pos)
/* ->stop() is called even if ->start() fails */
mutex_lock(&event_mutex);
- event_file = event_file_data(m->private);
+ event_file = event_file_file(m->private);
if (unlikely(!event_file))
return ERR_PTR(-ENODEV);
@@ -213,7 +213,7 @@ static int event_trigger_regex_open(struct inode *inode, struct file *file)
mutex_lock(&event_mutex);
- if (unlikely(!event_file_data(file))) {
+ if (unlikely(!event_file_file(file))) {
mutex_unlock(&event_mutex);
return -ENODEV;
}
@@ -293,7 +293,7 @@ static ssize_t event_trigger_regex_write(struct file *file,
strim(buf);
mutex_lock(&event_mutex);
- event_file = event_file_data(file);
+ event_file = event_file_file(file);
if (unlikely(!event_file)) {
mutex_unlock(&event_mutex);
kfree(buf);
diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
index 66a871553d4a..1439064f65d6 100644
--- a/kernel/trace/trace_osnoise.c
+++ b/kernel/trace/trace_osnoise.c
@@ -228,6 +228,11 @@ static inline struct osnoise_variables *this_cpu_osn_var(void)
return this_cpu_ptr(&per_cpu_osnoise_var);
}
+/*
+ * Protect the interface.
+ */
+static struct mutex interface_lock;
+
#ifdef CONFIG_TIMERLAT_TRACER
/*
* Runtime information for the timer mode.
@@ -259,14 +264,20 @@ static inline void tlat_var_reset(void)
{
struct timerlat_variables *tlat_var;
int cpu;
+
+ /* Synchronize with the timerlat interfaces */
+ mutex_lock(&interface_lock);
/*
* So far, all the values are initialized as 0, so
* zeroing the structure is perfect.
*/
for_each_cpu(cpu, cpu_online_mask) {
tlat_var = per_cpu_ptr(&per_cpu_timerlat_var, cpu);
+ if (tlat_var->kthread)
+ hrtimer_cancel(&tlat_var->timer);
memset(tlat_var, 0, sizeof(*tlat_var));
}
+ mutex_unlock(&interface_lock);
}
#else /* CONFIG_TIMERLAT_TRACER */
#define tlat_var_reset() do {} while (0)
@@ -332,11 +343,6 @@ struct timerlat_sample {
#endif
/*
- * Protect the interface.
- */
-static struct mutex interface_lock;
-
-/*
* Tracer data.
*/
static struct osnoise_data {
@@ -1535,7 +1541,7 @@ static int run_osnoise(void)
* This will eventually cause unwarranted noise as PREEMPT_RCU
* will force preemption as the means of ending the current
* grace period. We avoid this problem by calling
- * rcu_momentary_dyntick_idle(), which performs a zero duration
+ * rcu_momentary_eqs(), which performs a zero duration
* EQS allowing PREEMPT_RCU to end the current grace period.
* This call shouldn't be wrapped inside an RCU critical
* section.
@@ -1547,7 +1553,7 @@ static int run_osnoise(void)
if (!disable_irq)
local_irq_disable();
- rcu_momentary_dyntick_idle();
+ rcu_momentary_eqs();
if (!disable_irq)
local_irq_enable();
@@ -1612,6 +1618,7 @@ out:
static struct cpumask osnoise_cpumask;
static struct cpumask save_cpumask;
+static struct cpumask kthread_cpumask;
/*
* osnoise_sleep - sleep until the next period
@@ -1675,6 +1682,7 @@ static inline int osnoise_migration_pending(void)
*/
mutex_lock(&interface_lock);
this_cpu_osn_var()->kthread = NULL;
+ cpumask_clear_cpu(smp_processor_id(), &kthread_cpumask);
mutex_unlock(&interface_lock);
return 1;
@@ -1945,11 +1953,16 @@ static void stop_kthread(unsigned int cpu)
{
struct task_struct *kthread;
+ mutex_lock(&interface_lock);
kthread = per_cpu(per_cpu_osnoise_var, cpu).kthread;
if (kthread) {
- if (test_bit(OSN_WORKLOAD, &osnoise_options)) {
+ per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL;
+ mutex_unlock(&interface_lock);
+
+ if (cpumask_test_and_clear_cpu(cpu, &kthread_cpumask) &&
+ !WARN_ON(!test_bit(OSN_WORKLOAD, &osnoise_options))) {
kthread_stop(kthread);
- } else {
+ } else if (!WARN_ON(test_bit(OSN_WORKLOAD, &osnoise_options))) {
/*
* This is a user thread waiting on the timerlat_fd. We need
* to close all users, and the best way to guarantee this is
@@ -1958,8 +1971,8 @@ static void stop_kthread(unsigned int cpu)
kill_pid(kthread->thread_pid, SIGKILL, 1);
put_task_struct(kthread);
}
- per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL;
} else {
+ mutex_unlock(&interface_lock);
/* if no workload, just return */
if (!test_bit(OSN_WORKLOAD, &osnoise_options)) {
/*
@@ -1967,7 +1980,6 @@ static void stop_kthread(unsigned int cpu)
*/
per_cpu(per_cpu_osnoise_var, cpu).sampling = false;
barrier();
- return;
}
}
}
@@ -1982,12 +1994,8 @@ static void stop_per_cpu_kthreads(void)
{
int cpu;
- cpus_read_lock();
-
- for_each_online_cpu(cpu)
+ for_each_possible_cpu(cpu)
stop_kthread(cpu);
-
- cpus_read_unlock();
}
/*
@@ -2021,6 +2029,7 @@ static int start_kthread(unsigned int cpu)
}
per_cpu(per_cpu_osnoise_var, cpu).kthread = kthread;
+ cpumask_set_cpu(cpu, &kthread_cpumask);
return 0;
}
@@ -2048,8 +2057,16 @@ static int start_per_cpu_kthreads(void)
*/
cpumask_and(current_mask, cpu_online_mask, &osnoise_cpumask);
- for_each_possible_cpu(cpu)
+ for_each_possible_cpu(cpu) {
+ if (cpumask_test_and_clear_cpu(cpu, &kthread_cpumask)) {
+ struct task_struct *kthread;
+
+ kthread = per_cpu(per_cpu_osnoise_var, cpu).kthread;
+ if (!WARN_ON(!kthread))
+ kthread_stop(kthread);
+ }
per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL;
+ }
for_each_cpu(cpu, current_mask) {
retval = start_kthread(cpu);
@@ -2579,7 +2596,8 @@ static int timerlat_fd_release(struct inode *inode, struct file *file)
osn_var = per_cpu_ptr(&per_cpu_osnoise_var, cpu);
tlat_var = per_cpu_ptr(&per_cpu_timerlat_var, cpu);
- hrtimer_cancel(&tlat_var->timer);
+ if (tlat_var->kthread)
+ hrtimer_cancel(&tlat_var->timer);
memset(tlat_var, 0, sizeof(*tlat_var));
osn_var->sampling = 0;
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 97f1e4bc47dc..c4ad7cd7e778 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -942,7 +942,7 @@ static __init int test_graph_storage_multi(void)
{
struct fgraph_fixture *fixture;
bool printed = false;
- int i, ret;
+ int i, j, ret;
pr_cont("PASSED\n");
pr_info("Testing multiple fgraph storage on a function: ");
@@ -953,22 +953,35 @@ static __init int test_graph_storage_multi(void)
if (ret && ret != -ENODEV) {
pr_cont("*Could not set filter* ");
printed = true;
- goto out;
+ 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 out;
+ goto out1;
}
}
DYN_FTRACE_TEST_NAME();
-out:
+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];
- unregister_ftrace_graph(&fixture->gops);
+ ftrace_free_filter(&fixture->gops.ops);
if (fixture->error_str && !printed) {
pr_cont("*** %s ***", fixture->error_str);
diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c
index a4dcf0f24352..3a56e7c8aa4f 100644
--- a/kernel/trace/tracing_map.c
+++ b/kernel/trace/tracing_map.c
@@ -454,7 +454,7 @@ static struct tracing_map_elt *get_free_elt(struct tracing_map *map)
struct tracing_map_elt *elt = NULL;
int idx;
- idx = atomic_inc_return(&map->next_elt);
+ idx = atomic_fetch_add_unless(&map->next_elt, 1, map->max_elts);
if (idx < map->max_elts) {
elt = *(TRACING_MAP_ELT(map->elts, idx));
if (map->ops && map->ops->elt_init)
@@ -699,7 +699,7 @@ void tracing_map_clear(struct tracing_map *map)
{
unsigned int i;
- atomic_set(&map->next_elt, -1);
+ atomic_set(&map->next_elt, 0);
atomic64_set(&map->hits, 0);
atomic64_set(&map->drops, 0);
@@ -783,7 +783,7 @@ struct tracing_map *tracing_map_create(unsigned int map_bits,
map->map_bits = map_bits;
map->max_elts = (1 << map_bits);
- atomic_set(&map->next_elt, -1);
+ atomic_set(&map->next_elt, 0);
map->map_size = (1 << (map_bits + 1));
map->ops = ops;