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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c111
1 files changed, 61 insertions, 50 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c95b7292be7..e6fac0ffe6f 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1201,7 +1201,7 @@ void trace_graph_return(struct ftrace_graph_ret *trace)
* trace_vbprintk - write binary msg to tracing buffer
*
*/
-int trace_vbprintk(unsigned long ip, int depth, const char *fmt, va_list args)
+int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
{
static raw_spinlock_t trace_buf_lock =
(raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
@@ -1243,7 +1243,6 @@ int trace_vbprintk(unsigned long ip, int depth, const char *fmt, va_list args)
goto out_unlock;
entry = ring_buffer_event_data(event);
entry->ip = ip;
- entry->depth = depth;
entry->fmt = fmt;
memcpy(entry->buf, trace_buf, sizeof(u32) * len);
@@ -1261,7 +1260,7 @@ out:
}
EXPORT_SYMBOL_GPL(trace_vbprintk);
-int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
+int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
{
static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED;
static char trace_buf[TRACE_BUF_SIZE];
@@ -1298,7 +1297,6 @@ int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
goto out_unlock;
entry = ring_buffer_event_data(event);
entry->ip = ip;
- entry->depth = depth;
memcpy(&entry->buf, trace_buf, len);
entry->buf[len] = 0;
@@ -1701,38 +1699,6 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter)
return TRACE_TYPE_HANDLED;
}
-static enum print_line_t print_bprintk_msg_only(struct trace_iterator *iter)
-{
- struct trace_seq *s = &iter->seq;
- struct trace_entry *entry = iter->ent;
- struct bprint_entry *field;
- int ret;
-
- trace_assign_type(field, entry);
-
- ret = trace_seq_bprintf(s, field->fmt, field->buf);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- return TRACE_TYPE_HANDLED;
-}
-
-static enum print_line_t print_printk_msg_only(struct trace_iterator *iter)
-{
- struct trace_seq *s = &iter->seq;
- struct trace_entry *entry = iter->ent;
- struct print_entry *field;
- int ret;
-
- trace_assign_type(field, entry);
-
- ret = trace_seq_printf(s, "%s", field->buf);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- return TRACE_TYPE_HANDLED;
-}
-
static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
@@ -1794,12 +1760,12 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter)
if (iter->ent->type == TRACE_BPRINT &&
trace_flags & TRACE_ITER_PRINTK &&
trace_flags & TRACE_ITER_PRINTK_MSGONLY)
- return print_bprintk_msg_only(iter);
+ return trace_print_bprintk_msg_only(iter);
if (iter->ent->type == TRACE_PRINT &&
trace_flags & TRACE_ITER_PRINTK &&
trace_flags & TRACE_ITER_PRINTK_MSGONLY)
- return print_printk_msg_only(iter);
+ return trace_print_printk_msg_only(iter);
if (trace_flags & TRACE_ITER_BIN)
return print_bin_fmt(iter);
@@ -1948,9 +1914,14 @@ int tracing_open_generic(struct inode *inode, struct file *filp)
static int tracing_release(struct inode *inode, struct file *file)
{
struct seq_file *m = (struct seq_file *)file->private_data;
- struct trace_iterator *iter = m->private;
+ struct trace_iterator *iter;
int cpu;
+ if (!(file->f_mode & FMODE_READ))
+ return 0;
+
+ iter = m->private;
+
mutex_lock(&trace_types_lock);
for_each_tracing_cpu(cpu) {
if (iter->buffer_iter[cpu])
@@ -1976,12 +1947,24 @@ static int tracing_open(struct inode *inode, struct file *file)
struct trace_iterator *iter;
int ret = 0;
- iter = __tracing_open(inode, file);
- if (IS_ERR(iter))
- ret = PTR_ERR(iter);
- else if (trace_flags & TRACE_ITER_LATENCY_FMT)
- iter->iter_flags |= TRACE_FILE_LAT_FMT;
+ /* If this file was open for write, then erase contents */
+ if ((file->f_mode & FMODE_WRITE) &&
+ !(file->f_flags & O_APPEND)) {
+ long cpu = (long) inode->i_private;
+
+ if (cpu == TRACE_PIPE_ALL_CPU)
+ tracing_reset_online_cpus(&global_trace);
+ else
+ tracing_reset(&global_trace, cpu);
+ }
+ if (file->f_mode & FMODE_READ) {
+ iter = __tracing_open(inode, file);
+ if (IS_ERR(iter))
+ ret = PTR_ERR(iter);
+ else if (trace_flags & TRACE_ITER_LATENCY_FMT)
+ iter->iter_flags |= TRACE_FILE_LAT_FMT;
+ }
return ret;
}
@@ -2056,9 +2039,17 @@ static int show_traces_open(struct inode *inode, struct file *file)
return ret;
}
+static ssize_t
+tracing_write_stub(struct file *filp, const char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ return count;
+}
+
static const struct file_operations tracing_fops = {
.open = tracing_open,
.read = seq_read,
+ .write = tracing_write_stub,
.llseek = seq_lseek,
.release = tracing_release,
};
@@ -3154,7 +3145,7 @@ static int mark_printk(const char *fmt, ...)
int ret;
va_list args;
va_start(args, fmt);
- ret = trace_vprintk(0, -1, fmt, args);
+ ret = trace_vprintk(0, fmt, args);
va_end(args);
return ret;
}
@@ -3583,7 +3574,7 @@ static void tracing_init_debugfs_percpu(long cpu)
pr_warning("Could not create debugfs 'trace_pipe' entry\n");
/* per cpu trace */
- entry = debugfs_create_file("trace", 0444, d_cpu,
+ entry = debugfs_create_file("trace", 0644, d_cpu,
(void *) cpu, &tracing_fops);
if (!entry)
pr_warning("Could not create debugfs 'trace' entry\n");
@@ -3897,7 +3888,7 @@ static __init int tracer_init_debugfs(void)
if (!entry)
pr_warning("Could not create debugfs 'tracing_cpumask' entry\n");
- entry = debugfs_create_file("trace", 0444, d_tracer,
+ entry = debugfs_create_file("trace", 0644, d_tracer,
(void *) TRACE_PIPE_ALL_CPU, &tracing_fops);
if (!entry)
pr_warning("Could not create debugfs 'trace' entry\n");
@@ -4027,11 +4018,12 @@ trace_printk_seq(struct trace_seq *s)
trace_seq_init(s);
}
-void ftrace_dump(void)
+static void __ftrace_dump(bool disable_tracing)
{
static DEFINE_SPINLOCK(ftrace_dump_lock);
/* use static because iter can be a bit big for the stack */
static struct trace_iterator iter;
+ unsigned int old_userobj;
static int dump_ran;
unsigned long flags;
int cnt = 0, cpu;
@@ -4043,14 +4035,17 @@ void ftrace_dump(void)
dump_ran = 1;
- /* No turning back! */
tracing_off();
- ftrace_kill();
+
+ if (disable_tracing)
+ ftrace_kill();
for_each_tracing_cpu(cpu) {
atomic_inc(&global_trace.data[cpu]->disabled);
}
+ old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ;
+
/* don't look at user memory in panic mode */
trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
@@ -4095,10 +4090,26 @@ void ftrace_dump(void)
else
printk(KERN_TRACE "---------------------------------\n");
+ /* Re-enable tracing if requested */
+ if (!disable_tracing) {
+ trace_flags |= old_userobj;
+
+ for_each_tracing_cpu(cpu) {
+ atomic_dec(&global_trace.data[cpu]->disabled);
+ }
+ tracing_on();
+ }
+
out:
spin_unlock_irqrestore(&ftrace_dump_lock, flags);
}
+/* By default: disable tracing after the dump */
+void ftrace_dump(void)
+{
+ __ftrace_dump(true);
+}
+
__init static int tracer_alloc_buffers(void)
{
struct trace_array_cpu *data;