summaryrefslogtreecommitdiff
path: root/kernel/trace/trace_nop.c
diff options
context:
space:
mode:
authorDavid Woodhouse <David.Woodhouse@intel.com>2008-10-21 19:42:20 +0100
committerDavid Woodhouse <David.Woodhouse@intel.com>2008-10-21 19:42:20 +0100
commitb876d08f816527af257e13d89fb0d3b4b849223c (patch)
tree40569f568230f918ca55f04b355e251747f913ed /kernel/trace/trace_nop.c
parentb364776ad1208a71f0c53578c84619a395412a8d (diff)
parent2515ddc6db8eb49a79f0fe5e67ff09ac7c81eab4 (diff)
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts: drivers/pci/dmar.c
Diffstat (limited to 'kernel/trace/trace_nop.c')
-rw-r--r--kernel/trace/trace_nop.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/kernel/trace/trace_nop.c b/kernel/trace/trace_nop.c
new file mode 100644
index 000000000000..4592b4862515
--- /dev/null
+++ b/kernel/trace/trace_nop.c
@@ -0,0 +1,64 @@
+/*
+ * nop tracer
+ *
+ * Copyright (C) 2008 Steven Noonan <steven@uplinklabs.net>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/debugfs.h>
+#include <linux/ftrace.h>
+
+#include "trace.h"
+
+static struct trace_array *ctx_trace;
+
+static void start_nop_trace(struct trace_array *tr)
+{
+ /* Nothing to do! */
+}
+
+static void stop_nop_trace(struct trace_array *tr)
+{
+ /* Nothing to do! */
+}
+
+static void nop_trace_init(struct trace_array *tr)
+{
+ int cpu;
+ ctx_trace = tr;
+
+ for_each_online_cpu(cpu)
+ tracing_reset(tr, cpu);
+
+ if (tr->ctrl)
+ start_nop_trace(tr);
+}
+
+static void nop_trace_reset(struct trace_array *tr)
+{
+ if (tr->ctrl)
+ stop_nop_trace(tr);
+}
+
+static void nop_trace_ctrl_update(struct trace_array *tr)
+{
+ /* When starting a new trace, reset the buffers */
+ if (tr->ctrl)
+ start_nop_trace(tr);
+ else
+ stop_nop_trace(tr);
+}
+
+struct tracer nop_trace __read_mostly =
+{
+ .name = "nop",
+ .init = nop_trace_init,
+ .reset = nop_trace_reset,
+ .ctrl_update = nop_trace_ctrl_update,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_nop,
+#endif
+};
+