seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n");
}
+#ifdef CONFIG_TRACER_MAX_TRACE
+static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter)
+{
+ if (iter->trace->allocated_snapshot)
+ seq_printf(m, "#\n# * Snapshot is allocated *\n#\n");
+ else
+ seq_printf(m, "#\n# * Snapshot is freed *\n#\n");
+
+ seq_printf(m, "# Snapshot commands:\n");
+ seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n");
+ seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n");
+ seq_printf(m, "# Takes a snapshot of the main buffer.\n");
+ seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n");
+ seq_printf(m, "# (Doesn't have to be '2' works with any number that\n");
+ seq_printf(m, "# is not a '0' or '1')\n");
+}
+#else
+/* Should never be called */
+static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { }
+#endif
+
static int s_show(struct seq_file *m, void *v)
{
struct trace_iterator *iter = v;
seq_puts(m, "#\n");
test_ftrace_alive(m);
}
- if (iter->trace && iter->trace->print_header)
+ if (iter->snapshot && trace_empty(iter))
+ print_snapshot_help(m, iter);
+ else if (iter->trace && iter->trace->print_header)
iter->trace->print_header(m);
else
trace_default_header(m);