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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c90
1 files changed, 60 insertions, 30 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e9cbb96cd99e..c456c2b06277 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -494,8 +494,10 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
* not modified.
*/
pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL);
- if (!pid_list)
+ if (!pid_list) {
+ trace_parser_put(&parser);
return -ENOMEM;
+ }
pid_list->pid_max = READ_ONCE(pid_max);
@@ -505,6 +507,7 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3);
if (!pid_list->pids) {
+ trace_parser_put(&parser);
kfree(pid_list);
return -ENOMEM;
}
@@ -3381,6 +3384,8 @@ static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file
const char tgid_space[] = " ";
const char space[] = " ";
+ print_event_info(buf, m);
+
seq_printf(m, "# %s _-----=> irqs-off\n",
tgid ? tgid_space : space);
seq_printf(m, "# %s / _----=> need-resched\n",
@@ -3899,7 +3904,8 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
if (iter->cpu_file == RING_BUFFER_ALL_CPUS) {
for_each_tracing_cpu(cpu) {
iter->buffer_iter[cpu] =
- ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
+ ring_buffer_read_prepare(iter->trace_buffer->buffer,
+ cpu, GFP_KERNEL);
}
ring_buffer_read_prepare_sync();
for_each_tracing_cpu(cpu) {
@@ -3909,7 +3915,8 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
} else {
cpu = iter->cpu_file;
iter->buffer_iter[cpu] =
- ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
+ ring_buffer_read_prepare(iter->trace_buffer->buffer,
+ cpu, GFP_KERNEL);
ring_buffer_read_prepare_sync();
ring_buffer_read_start(iter->buffer_iter[cpu]);
tracing_iter_reset(iter, cpu);
@@ -4145,9 +4152,14 @@ static int show_traces_open(struct inode *inode, struct file *file)
if (tracing_disabled)
return -ENODEV;
+ if (trace_array_get(tr) < 0)
+ return -ENODEV;
+
ret = seq_open(file, &show_traces_seq_ops);
- if (ret)
+ if (ret) {
+ trace_array_put(tr);
return ret;
+ }
m = file->private_data;
m->private = tr;
@@ -4155,6 +4167,14 @@ static int show_traces_open(struct inode *inode, struct file *file)
return 0;
}
+static int show_traces_release(struct inode *inode, struct file *file)
+{
+ struct trace_array *tr = inode->i_private;
+
+ trace_array_put(tr);
+ return seq_release(inode, file);
+}
+
static ssize_t
tracing_write_stub(struct file *filp, const char __user *ubuf,
size_t count, loff_t *ppos)
@@ -4185,8 +4205,8 @@ static const struct file_operations tracing_fops = {
static const struct file_operations show_traces_fops = {
.open = show_traces_open,
.read = seq_read,
- .release = seq_release,
.llseek = seq_lseek,
+ .release = show_traces_release,
};
static ssize_t
@@ -4348,6 +4368,10 @@ int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set)
int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled)
{
+ if ((mask == TRACE_ITER_RECORD_TGID) ||
+ (mask == TRACE_ITER_RECORD_CMD))
+ lockdep_assert_held(&event_mutex);
+
/* do nothing if flag is already set */
if (!!(tr->trace_flags & mask) == !!enabled)
return 0;
@@ -4413,6 +4437,7 @@ static int trace_set_options(struct trace_array *tr, char *option)
cmp += 2;
}
+ mutex_lock(&event_mutex);
mutex_lock(&trace_types_lock);
for (i = 0; trace_options[i]; i++) {
@@ -4427,6 +4452,7 @@ static int trace_set_options(struct trace_array *tr, char *option)
ret = set_tracer_option(tr, cmp, neg);
mutex_unlock(&trace_types_lock);
+ mutex_unlock(&event_mutex);
/*
* If the first trailing whitespace is replaced with '\0' by strstrip,
@@ -5602,7 +5628,6 @@ out:
return ret;
fail:
- kfree(iter->trace);
kfree(iter);
__trace_array_put(tr);
mutex_unlock(&trace_types_lock);
@@ -5745,6 +5770,7 @@ waitagain:
sizeof(struct trace_iterator) -
offsetof(struct trace_iterator, seq));
cpumask_clear(iter->started);
+ trace_seq_init(&iter->seq);
iter->pos = -1;
trace_event_read_lock();
@@ -6388,11 +6414,13 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
break;
}
#endif
- if (!tr->allocated_snapshot) {
+ if (tr->allocated_snapshot)
+ ret = resize_buffer_duplicate_size(&tr->max_buffer,
+ &tr->trace_buffer, iter->cpu_file);
+ else
ret = tracing_alloc_snapshot_instance(tr);
- if (ret < 0)
- break;
- }
+ if (ret < 0)
+ break;
local_irq_disable();
/* Now, we're going to swap */
if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
@@ -6713,28 +6741,36 @@ struct buffer_ref {
struct ring_buffer *buffer;
void *page;
int cpu;
- int ref;
+ refcount_t refcount;
};
+static void buffer_ref_release(struct buffer_ref *ref)
+{
+ if (!refcount_dec_and_test(&ref->refcount))
+ return;
+ ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page);
+ kfree(ref);
+}
+
static void buffer_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct buffer_ref *ref = (struct buffer_ref *)buf->private;
- if (--ref->ref)
- return;
-
- ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page);
- kfree(ref);
+ buffer_ref_release(ref);
buf->private = 0;
}
-static void buffer_pipe_buf_get(struct pipe_inode_info *pipe,
+static bool buffer_pipe_buf_get(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct buffer_ref *ref = (struct buffer_ref *)buf->private;
- ref->ref++;
+ if (refcount_read(&ref->refcount) > INT_MAX/2)
+ return false;
+
+ refcount_inc(&ref->refcount);
+ return true;
}
/* Pipe buffer operations for a buffer. */
@@ -6742,7 +6778,7 @@ static const struct pipe_buf_operations buffer_pipe_buf_ops = {
.can_merge = 0,
.confirm = generic_pipe_buf_confirm,
.release = buffer_pipe_buf_release,
- .steal = generic_pipe_buf_steal,
+ .steal = generic_pipe_buf_nosteal,
.get = buffer_pipe_buf_get,
};
@@ -6755,11 +6791,7 @@ static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i)
struct buffer_ref *ref =
(struct buffer_ref *)spd->partial[i].private;
- if (--ref->ref)
- return;
-
- ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page);
- kfree(ref);
+ buffer_ref_release(ref);
spd->partial[i].private = 0;
}
@@ -6814,7 +6846,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
break;
}
- ref->ref = 1;
+ refcount_set(&ref->refcount, 1);
ref->buffer = iter->trace_buffer->buffer;
ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file);
if (IS_ERR(ref->page)) {
@@ -7347,9 +7379,11 @@ trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt,
if (val != 0 && val != 1)
return -EINVAL;
+ mutex_lock(&event_mutex);
mutex_lock(&trace_types_lock);
ret = set_tracer_flag(tr, 1 << index, val);
mutex_unlock(&trace_types_lock);
+ mutex_unlock(&event_mutex);
if (ret < 0)
return ret;
@@ -8239,12 +8273,8 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
cnt++;
- /* reset all but tr, trace, and overruns */
- memset(&iter.seq, 0,
- sizeof(struct trace_iterator) -
- offsetof(struct trace_iterator, seq));
+ trace_iterator_reset(&iter);
iter.iter_flags |= TRACE_FILE_LAT_FMT;
- iter.pos = -1;
if (trace_find_next_entry_inc(&iter) != NULL) {
int ret;