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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c227
1 files changed, 102 insertions, 125 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 0cd500bffd9b..882ec1dd1515 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1224,18 +1224,17 @@ void tracing_reset_current(int cpu)
tracing_reset(&global_trace.trace_buffer, cpu);
}
+/* Must have trace_types_lock held */
void tracing_reset_all_online_cpus(void)
{
struct trace_array *tr;
- mutex_lock(&trace_types_lock);
list_for_each_entry(tr, &ftrace_trace_arrays, list) {
tracing_reset_online_cpus(&tr->trace_buffer);
#ifdef CONFIG_TRACER_MAX_TRACE
tracing_reset_online_cpus(&tr->max_buffer);
#endif
}
- mutex_unlock(&trace_types_lock);
}
#define SAVED_CMDLINES 128
@@ -2843,6 +2842,17 @@ static int s_show(struct seq_file *m, void *v)
return 0;
}
+/*
+ * Should be used after trace_array_get(), trace_types_lock
+ * ensures that i_cdev was already initialized.
+ */
+static inline int tracing_get_cpu(struct inode *inode)
+{
+ if (inode->i_cdev) /* See trace_create_cpu_file() */
+ return (long)inode->i_cdev - 1;
+ return RING_BUFFER_ALL_CPUS;
+}
+
static const struct seq_operations tracer_seq_ops = {
.start = s_start,
.next = s_next,
@@ -2851,9 +2861,9 @@ static const struct seq_operations tracer_seq_ops = {
};
static struct trace_iterator *
-__tracing_open(struct trace_array *tr, struct trace_cpu *tc,
- struct inode *inode, struct file *file, bool snapshot)
+__tracing_open(struct inode *inode, struct file *file, bool snapshot)
{
+ struct trace_array *tr = inode->i_private;
struct trace_iterator *iter;
int cpu;
@@ -2894,8 +2904,8 @@ __tracing_open(struct trace_array *tr, struct trace_cpu *tc,
iter->trace_buffer = &tr->trace_buffer;
iter->snapshot = snapshot;
iter->pos = -1;
+ iter->cpu_file = tracing_get_cpu(inode);
mutex_init(&iter->mutex);
- iter->cpu_file = tc->cpu;
/* Notify the tracer early; before we stop tracing. */
if (iter->trace && iter->trace->open)
@@ -2971,45 +2981,22 @@ static int tracing_open_generic_tr(struct inode *inode, struct file *filp)
filp->private_data = inode->i_private;
return 0;
-
-}
-
-static int tracing_open_generic_tc(struct inode *inode, struct file *filp)
-{
- struct trace_cpu *tc = inode->i_private;
- struct trace_array *tr = tc->tr;
-
- if (tracing_disabled)
- return -ENODEV;
-
- if (trace_array_get(tr) < 0)
- return -ENODEV;
-
- filp->private_data = inode->i_private;
-
- return 0;
-
}
static int tracing_release(struct inode *inode, struct file *file)
{
+ struct trace_array *tr = inode->i_private;
struct seq_file *m = file->private_data;
struct trace_iterator *iter;
- struct trace_array *tr;
int cpu;
- /* Writes do not use seq_file, need to grab tr from inode */
if (!(file->f_mode & FMODE_READ)) {
- struct trace_cpu *tc = inode->i_private;
-
- trace_array_put(tc->tr);
+ trace_array_put(tr);
return 0;
}
+ /* Writes do not use seq_file */
iter = m->private;
- tr = iter->tr;
- trace_array_put(tr);
-
mutex_lock(&trace_types_lock);
for_each_tracing_cpu(cpu) {
@@ -3023,6 +3010,9 @@ static int tracing_release(struct inode *inode, struct file *file)
if (!iter->snapshot)
/* reenable tracing if it was previously enabled */
tracing_start_tr(tr);
+
+ __trace_array_put(tr);
+
mutex_unlock(&trace_types_lock);
mutex_destroy(&iter->mutex);
@@ -3042,15 +3032,6 @@ static int tracing_release_generic_tr(struct inode *inode, struct file *file)
return 0;
}
-static int tracing_release_generic_tc(struct inode *inode, struct file *file)
-{
- struct trace_cpu *tc = inode->i_private;
- struct trace_array *tr = tc->tr;
-
- trace_array_put(tr);
- return 0;
-}
-
static int tracing_single_release_tr(struct inode *inode, struct file *file)
{
struct trace_array *tr = inode->i_private;
@@ -3062,8 +3043,7 @@ static int tracing_single_release_tr(struct inode *inode, struct file *file)
static int tracing_open(struct inode *inode, struct file *file)
{
- struct trace_cpu *tc = inode->i_private;
- struct trace_array *tr = tc->tr;
+ struct trace_array *tr = inode->i_private;
struct trace_iterator *iter;
int ret = 0;
@@ -3071,16 +3051,17 @@ static int tracing_open(struct inode *inode, struct file *file)
return -ENODEV;
/* If this file was open for write, then erase contents */
- if ((file->f_mode & FMODE_WRITE) &&
- (file->f_flags & O_TRUNC)) {
- if (tc->cpu == RING_BUFFER_ALL_CPUS)
+ if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
+ int cpu = tracing_get_cpu(inode);
+
+ if (cpu == RING_BUFFER_ALL_CPUS)
tracing_reset_online_cpus(&tr->trace_buffer);
else
- tracing_reset(&tr->trace_buffer, tc->cpu);
+ tracing_reset(&tr->trace_buffer, cpu);
}
if (file->f_mode & FMODE_READ) {
- iter = __tracing_open(tr, tc, inode, file, false);
+ iter = __tracing_open(inode, file, false);
if (IS_ERR(iter))
ret = PTR_ERR(iter);
else if (trace_flags & TRACE_ITER_LATENCY_FMT)
@@ -3447,6 +3428,7 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
static int tracing_trace_options_open(struct inode *inode, struct file *file)
{
struct trace_array *tr = inode->i_private;
+ int ret;
if (tracing_disabled)
return -ENODEV;
@@ -3454,7 +3436,11 @@ static int tracing_trace_options_open(struct inode *inode, struct file *file)
if (trace_array_get(tr) < 0)
return -ENODEV;
- return single_open(file, tracing_trace_options_show, inode->i_private);
+ ret = single_open(file, tracing_trace_options_show, inode->i_private);
+ if (ret < 0)
+ trace_array_put(tr);
+
+ return ret;
}
static const struct file_operations tracing_iter_fops = {
@@ -3537,14 +3523,14 @@ static const char readme_msg[] =
"\n snapshot\t\t- Like 'trace' but shows the content of the static snapshot buffer\n"
"\t\t\t Read the contents for more information\n"
#endif
-#ifdef CONFIG_STACKTRACE
+#ifdef CONFIG_STACK_TRACER
" stack_trace\t\t- Shows the max stack trace when active\n"
" stack_max_size\t- Shows current max stack size that was traced\n"
"\t\t\t Write into this file to reset the max size (trigger a new trace)\n"
#ifdef CONFIG_DYNAMIC_FTRACE
" stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace traces\n"
#endif
-#endif /* CONFIG_STACKTRACE */
+#endif /* CONFIG_STACK_TRACER */
;
static ssize_t
@@ -3941,8 +3927,7 @@ tracing_max_lat_write(struct file *filp, const char __user *ubuf,
static int tracing_open_pipe(struct inode *inode, struct file *filp)
{
- struct trace_cpu *tc = inode->i_private;
- struct trace_array *tr = tc->tr;
+ struct trace_array *tr = inode->i_private;
struct trace_iterator *iter;
int ret = 0;
@@ -3958,6 +3943,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
if (!iter) {
ret = -ENOMEM;
+ __trace_array_put(tr);
goto out;
}
@@ -3987,9 +3973,9 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
if (trace_clocks[tr->clock_id].in_ns)
iter->iter_flags |= TRACE_FILE_TIME_IN_NS;
- iter->cpu_file = tc->cpu;
- iter->tr = tc->tr;
- iter->trace_buffer = &tc->tr->trace_buffer;
+ iter->tr = tr;
+ iter->trace_buffer = &tr->trace_buffer;
+ iter->cpu_file = tracing_get_cpu(inode);
mutex_init(&iter->mutex);
filp->private_data = iter;
@@ -4012,8 +3998,7 @@ fail:
static int tracing_release_pipe(struct inode *inode, struct file *file)
{
struct trace_iterator *iter = file->private_data;
- struct trace_cpu *tc = inode->i_private;
- struct trace_array *tr = tc->tr;
+ struct trace_array *tr = inode->i_private;
mutex_lock(&trace_types_lock);
@@ -4366,15 +4351,16 @@ static ssize_t
tracing_entries_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- struct trace_cpu *tc = filp->private_data;
- struct trace_array *tr = tc->tr;
+ struct inode *inode = file_inode(filp);
+ struct trace_array *tr = inode->i_private;
+ int cpu = tracing_get_cpu(inode);
char buf[64];
int r = 0;
ssize_t ret;
mutex_lock(&trace_types_lock);
- if (tc->cpu == RING_BUFFER_ALL_CPUS) {
+ if (cpu == RING_BUFFER_ALL_CPUS) {
int cpu, buf_size_same;
unsigned long size;
@@ -4401,7 +4387,7 @@ tracing_entries_read(struct file *filp, char __user *ubuf,
} else
r = sprintf(buf, "X\n");
} else
- r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, tc->cpu)->entries >> 10);
+ r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10);
mutex_unlock(&trace_types_lock);
@@ -4413,7 +4399,8 @@ static ssize_t
tracing_entries_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- struct trace_cpu *tc = filp->private_data;
+ struct inode *inode = file_inode(filp);
+ struct trace_array *tr = inode->i_private;
unsigned long val;
int ret;
@@ -4427,8 +4414,7 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
/* value is in KB */
val <<= 10;
-
- ret = tracing_resize_ring_buffer(tc->tr, val, tc->cpu);
+ ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode));
if (ret < 0)
return ret;
@@ -4689,8 +4675,7 @@ struct ftrace_buffer_info {
#ifdef CONFIG_TRACER_SNAPSHOT
static int tracing_snapshot_open(struct inode *inode, struct file *file)
{
- struct trace_cpu *tc = inode->i_private;
- struct trace_array *tr = tc->tr;
+ struct trace_array *tr = inode->i_private;
struct trace_iterator *iter;
struct seq_file *m;
int ret = 0;
@@ -4699,26 +4684,29 @@ static int tracing_snapshot_open(struct inode *inode, struct file *file)
return -ENODEV;
if (file->f_mode & FMODE_READ) {
- iter = __tracing_open(tr, tc, inode, file, true);
+ iter = __tracing_open(inode, file, true);
if (IS_ERR(iter))
ret = PTR_ERR(iter);
} else {
/* Writes still need the seq_file to hold the private data */
+ ret = -ENOMEM;
m = kzalloc(sizeof(*m), GFP_KERNEL);
if (!m)
- return -ENOMEM;
+ goto out;
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
if (!iter) {
kfree(m);
- return -ENOMEM;
+ goto out;
}
+ ret = 0;
+
iter->tr = tr;
- iter->trace_buffer = &tc->tr->max_buffer;
- iter->cpu_file = tc->cpu;
+ iter->trace_buffer = &tr->max_buffer;
+ iter->cpu_file = tracing_get_cpu(inode);
m->private = iter;
file->private_data = m;
}
-
+out:
if (ret < 0)
trace_array_put(tr);
@@ -4873,11 +4861,11 @@ static const struct file_operations tracing_pipe_fops = {
};
static const struct file_operations tracing_entries_fops = {
- .open = tracing_open_generic_tc,
+ .open = tracing_open_generic_tr,
.read = tracing_entries_read,
.write = tracing_entries_write,
.llseek = generic_file_llseek,
- .release = tracing_release_generic_tc,
+ .release = tracing_release_generic_tr,
};
static const struct file_operations tracing_total_entries_fops = {
@@ -4929,8 +4917,7 @@ static const struct file_operations snapshot_raw_fops = {
static int tracing_buffers_open(struct inode *inode, struct file *filp)
{
- struct trace_cpu *tc = inode->i_private;
- struct trace_array *tr = tc->tr;
+ struct trace_array *tr = inode->i_private;
struct ftrace_buffer_info *info;
int ret;
@@ -4948,10 +4935,8 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp)
mutex_lock(&trace_types_lock);
- tr->ref++;
-
info->iter.tr = tr;
- info->iter.cpu_file = tc->cpu;
+ info->iter.cpu_file = tracing_get_cpu(inode);
info->iter.trace = tr->current_trace;
info->iter.trace_buffer = &tr->trace_buffer;
info->spare = NULL;
@@ -5268,14 +5253,14 @@ static ssize_t
tracing_stats_read(struct file *filp, char __user *ubuf,
size_t count, loff_t *ppos)
{
- struct trace_cpu *tc = filp->private_data;
- struct trace_array *tr = tc->tr;
+ struct inode *inode = file_inode(filp);
+ struct trace_array *tr = inode->i_private;
struct trace_buffer *trace_buf = &tr->trace_buffer;
+ int cpu = tracing_get_cpu(inode);
struct trace_seq *s;
unsigned long cnt;
unsigned long long t;
unsigned long usec_rem;
- int cpu = tc->cpu;
s = kmalloc(sizeof(*s), GFP_KERNEL);
if (!s)
@@ -5328,9 +5313,10 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
}
static const struct file_operations tracing_stats_fops = {
- .open = tracing_open_generic,
+ .open = tracing_open_generic_tr,
.read = tracing_stats_read,
.llseek = generic_file_llseek,
+ .release = tracing_release_generic_tr,
};
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -5519,10 +5505,20 @@ static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu)
return tr->percpu_dir;
}
+static struct dentry *
+trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent,
+ void *data, long cpu, const struct file_operations *fops)
+{
+ struct dentry *ret = trace_create_file(name, mode, parent, data, fops);
+
+ if (ret) /* See tracing_get_cpu() */
+ ret->d_inode->i_cdev = (void *)(cpu + 1);
+ return ret;
+}
+
static void
tracing_init_debugfs_percpu(struct trace_array *tr, long cpu)
{
- struct trace_array_cpu *data = per_cpu_ptr(tr->trace_buffer.data, cpu);
struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu);
struct dentry *d_cpu;
char cpu_dir[30]; /* 30 characters should be more than enough */
@@ -5538,28 +5534,28 @@ tracing_init_debugfs_percpu(struct trace_array *tr, long cpu)
}
/* per cpu trace_pipe */
- trace_create_file("trace_pipe", 0444, d_cpu,
- (void *)&data->trace_cpu, &tracing_pipe_fops);
+ trace_create_cpu_file("trace_pipe", 0444, d_cpu,
+ tr, cpu, &tracing_pipe_fops);
/* per cpu trace */
- trace_create_file("trace", 0644, d_cpu,
- (void *)&data->trace_cpu, &tracing_fops);
+ trace_create_cpu_file("trace", 0644, d_cpu,
+ tr, cpu, &tracing_fops);
- trace_create_file("trace_pipe_raw", 0444, d_cpu,
- (void *)&data->trace_cpu, &tracing_buffers_fops);
+ trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu,
+ tr, cpu, &tracing_buffers_fops);
- trace_create_file("stats", 0444, d_cpu,
- (void *)&data->trace_cpu, &tracing_stats_fops);
+ trace_create_cpu_file("stats", 0444, d_cpu,
+ tr, cpu, &tracing_stats_fops);
- trace_create_file("buffer_size_kb", 0444, d_cpu,
- (void *)&data->trace_cpu, &tracing_entries_fops);
+ trace_create_cpu_file("buffer_size_kb", 0444, d_cpu,
+ tr, cpu, &tracing_entries_fops);
#ifdef CONFIG_TRACER_SNAPSHOT
- trace_create_file("snapshot", 0644, d_cpu,
- (void *)&data->trace_cpu, &snapshot_fops);
+ trace_create_cpu_file("snapshot", 0644, d_cpu,
+ tr, cpu, &snapshot_fops);
- trace_create_file("snapshot_raw", 0444, d_cpu,
- (void *)&data->trace_cpu, &snapshot_raw_fops);
+ trace_create_cpu_file("snapshot_raw", 0444, d_cpu,
+ tr, cpu, &snapshot_raw_fops);
#endif
}
@@ -5868,17 +5864,6 @@ struct dentry *trace_instance_dir;
static void
init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer);
-static void init_trace_buffers(struct trace_array *tr, struct trace_buffer *buf)
-{
- int cpu;
-
- for_each_tracing_cpu(cpu) {
- memset(per_cpu_ptr(buf->data, cpu), 0, sizeof(struct trace_array_cpu));
- per_cpu_ptr(buf->data, cpu)->trace_cpu.cpu = cpu;
- per_cpu_ptr(buf->data, cpu)->trace_cpu.tr = tr;
- }
-}
-
static int
allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size)
{
@@ -5896,8 +5881,6 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size
return -ENOMEM;
}
- init_trace_buffers(tr, buf);
-
/* Allocate the first page for all buffers */
set_buffer_entries(&tr->trace_buffer,
ring_buffer_size(tr->trace_buffer.buffer, 0));
@@ -5964,17 +5947,15 @@ static int new_instance_create(const char *name)
if (allocate_trace_buffers(tr, trace_buf_size) < 0)
goto out_free_tr;
- /* Holder for file callbacks */
- tr->trace_cpu.cpu = RING_BUFFER_ALL_CPUS;
- tr->trace_cpu.tr = tr;
-
tr->dir = debugfs_create_dir(name, trace_instance_dir);
if (!tr->dir)
goto out_free_tr;
ret = event_trace_add_tracer(tr->dir, tr);
- if (ret)
+ if (ret) {
+ debugfs_remove_recursive(tr->dir);
goto out_free_tr;
+ }
init_tracer_debugfs(tr, tr->dir);
@@ -6120,13 +6101,13 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
tr, &tracing_iter_fops);
trace_create_file("trace", 0644, d_tracer,
- (void *)&tr->trace_cpu, &tracing_fops);
+ tr, &tracing_fops);
trace_create_file("trace_pipe", 0444, d_tracer,
- (void *)&tr->trace_cpu, &tracing_pipe_fops);
+ tr, &tracing_pipe_fops);
trace_create_file("buffer_size_kb", 0644, d_tracer,
- (void *)&tr->trace_cpu, &tracing_entries_fops);
+ tr, &tracing_entries_fops);
trace_create_file("buffer_total_size_kb", 0444, d_tracer,
tr, &tracing_total_entries_fops);
@@ -6141,11 +6122,11 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
&trace_clock_fops);
trace_create_file("tracing_on", 0644, d_tracer,
- tr, &rb_simple_fops);
+ tr, &rb_simple_fops);
#ifdef CONFIG_TRACER_SNAPSHOT
trace_create_file("snapshot", 0644, d_tracer,
- (void *)&tr->trace_cpu, &snapshot_fops);
+ tr, &snapshot_fops);
#endif
for_each_tracing_cpu(cpu)
@@ -6439,10 +6420,6 @@ __init static int tracer_alloc_buffers(void)
global_trace.flags = TRACE_ARRAY_FL_GLOBAL;
- /* Holder for file callbacks */
- global_trace.trace_cpu.cpu = RING_BUFFER_ALL_CPUS;
- global_trace.trace_cpu.tr = &global_trace;
-
INIT_LIST_HEAD(&global_trace.systems);
INIT_LIST_HEAD(&global_trace.events);
list_add(&global_trace.list, &ftrace_trace_arrays);