Re: linux-next: Tree for Sep 7 (kernel/trace/trace_hwlat.c)

From: Steven Rostedt
Date: Wed Sep 07 2016 - 15:38:26 EST


On Wed, 7 Sep 2016 14:48:38 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> Will send another one soon.

What about this?

-- Steve

commit 64cfdb9788bf3fb2bf6c30701fc3644f25e76df2
Author: Steven Rostedt (Red Hat) <rostedt@xxxxxxxxxxx>
Date: Wed Sep 7 12:45:09 2016 -0400

tracing: Have max_latency be defined for HWLAT_TRACER as well

The hwlat tracer uses tr->max_latency, and if it's the only tracer enabled
that uses it, the build will fail. Add max_latency and its file when the
hwlat tracer is enabled.

Link: http://lkml.kernel.org/r/20160907175258.1f17a8ba@xxxxxxxxxxxxxxxx

Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 474cc814e16d..e0d0cfc1aa20 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4945,7 +4945,7 @@ out:
return ret;
}

-#ifdef CONFIG_TRACER_MAX_TRACE
+#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)

static ssize_t
tracing_max_lat_read(struct file *filp, char __user *ubuf,
@@ -5867,7 +5867,7 @@ static const struct file_operations tracing_thresh_fops = {
.llseek = generic_file_llseek,
};

-#ifdef CONFIG_TRACER_MAX_TRACE
+#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
static const struct file_operations tracing_max_lat_fops = {
.open = tracing_open_generic,
.read = tracing_max_lat_read,
@@ -7195,7 +7195,7 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)

create_trace_options_dir(tr);

-#ifdef CONFIG_TRACER_MAX_TRACE
+#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
trace_create_file("tracing_max_latency", 0644, d_tracer,
&tr->max_latency, &tracing_max_lat_fops);
#endif
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 1d866b0c1567..fd24b1f9ac43 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -214,6 +214,8 @@ struct trace_array {
*/
struct trace_buffer max_buffer;
bool allocated_snapshot;
+#endif
+#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
unsigned long max_latency;
#endif
struct trace_pid_list __rcu *filtered_pids;