Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
ftrace: prevent recursion
tracing, doc: update mmiotrace documentation
x86, mmiotrace: fix buffer overrun detection
function tracing: fix wrong position computing of stack_trace
diff --git a/Documentation/tracers/mmiotrace.txt b/Documentation/tracers/mmiotrace.txt
index 5bbbe20..cde23b4 100644
--- a/Documentation/tracers/mmiotrace.txt
+++ b/Documentation/tracers/mmiotrace.txt
@@ -37,7 +37,7 @@
$ cat /debug/tracing/trace_pipe > mydump.txt &
Start X or whatever.
$ echo "X is up" > /debug/tracing/trace_marker
-$ echo none > /debug/tracing/current_tracer
+$ echo nop > /debug/tracing/current_tracer
Check for lost events.
@@ -66,7 +66,7 @@
do.
Shut down mmiotrace (requires root privileges):
-$ echo none > /debug/tracing/current_tracer
+$ echo nop > /debug/tracing/current_tracer
The 'cat' process exits. If it does not, kill it by issuing 'fg' command and
pressing ctrl+c.
@@ -81,7 +81,9 @@
$ cat /debug/tracing/trace_entries
gives you a number. Approximately double this number and write it back, for
instance:
+$ echo 0 > /debug/tracing/tracing_enabled
$ echo 128000 > /debug/tracing/trace_entries
+$ echo 1 > /debug/tracing/tracing_enabled
Then start again from the top.
If you are doing a trace for a driver project, e.g. Nouveau, you should also
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index f780e95..668bbb5 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1215,7 +1215,7 @@
out:
if (resched)
- preempt_enable_notrace();
+ preempt_enable_no_resched_notrace();
else
preempt_enable_notrace();
return NULL;
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index f284846..e62cbf7 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -18,12 +18,14 @@
static struct trace_array *mmio_trace_array;
static bool overrun_detected;
+static unsigned long prev_overruns;
static void mmio_reset_data(struct trace_array *tr)
{
int cpu;
overrun_detected = false;
+ prev_overruns = 0;
tr->time_start = ftrace_now(tr->cpu);
for_each_online_cpu(cpu)
@@ -128,16 +130,12 @@
static unsigned long count_overruns(struct trace_iterator *iter)
{
- int cpu;
unsigned long cnt = 0;
-/* FIXME: */
-#if 0
- for_each_online_cpu(cpu) {
- cnt += iter->overrun[cpu];
- iter->overrun[cpu] = 0;
- }
-#endif
- (void)cpu;
+ unsigned long over = ring_buffer_overruns(iter->tr->buffer);
+
+ if (over > prev_overruns)
+ cnt = over - prev_overruns;
+ prev_overruns = over;
return cnt;
}
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index be682b6..3bdb44b 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -184,11 +184,16 @@
static void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
- long i = (long)m->private;
+ long i;
(*pos)++;
- i++;
+ if (v == SEQ_START_TOKEN)
+ i = 0;
+ else {
+ i = *(long *)v;
+ i++;
+ }
if (i >= max_stack_trace.nr_entries ||
stack_dump_trace[i] == ULONG_MAX)
@@ -201,12 +206,15 @@
static void *t_start(struct seq_file *m, loff_t *pos)
{
- void *t = &m->private;
+ void *t = SEQ_START_TOKEN;
loff_t l = 0;
local_irq_disable();
__raw_spin_lock(&max_stack_lock);
+ if (*pos == 0)
+ return SEQ_START_TOKEN;
+
for (; t && l < *pos; t = t_next(m, t, &l))
;
@@ -235,10 +243,10 @@
static int t_show(struct seq_file *m, void *v)
{
- long i = *(long *)v;
+ long i;
int size;
- if (i < 0) {
+ if (v == SEQ_START_TOKEN) {
seq_printf(m, " Depth Size Location"
" (%d entries)\n"
" ----- ---- --------\n",
@@ -246,6 +254,8 @@
return 0;
}
+ i = *(long *)v;
+
if (i >= max_stack_trace.nr_entries ||
stack_dump_trace[i] == ULONG_MAX)
return 0;
@@ -275,10 +285,6 @@
int ret;
ret = seq_open(file, &stack_trace_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = (void *)-1;
- }
return ret;
}