ftrace: change trace.c to use registered events
Impact: rework trace.c to use new event register API
Almost every ftrace event has to implement its output display in
trace.c through a different function. Some events did not handle
all the formats (trace, latency-trace, raw, hex, binary), and
this method does not scale well.
This patch converts the format functions to use the event API to
find the event and and print its format. Currently, we have
a print function for trace, latency_trace, raw, hex and binary.
A trace_nop_print is available if the event wants to avoid output
on a particular format.
Perhaps other tracers could use this in the future (like mmiotrace and
function_graph).
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index 6c00feb..c15222a 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -14,7 +14,9 @@
#include <linux/hash.h>
#include <linux/fs.h>
#include <asm/local.h>
+
#include "trace.h"
+#include "trace_output.h"
#ifdef CONFIG_BRANCH_TRACER
@@ -142,6 +144,49 @@
stop_branch_trace(tr);
}
+static int
+trace_print_print(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct print_entry *field;
+
+ trace_assign_type(field, entry);
+
+ if (seq_print_ip_sym(s, field->ip, flags))
+ goto partial;
+
+ if (trace_seq_printf(s, ": %s", field->buf))
+ goto partial;
+
+ partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+static int
+trace_branch_print(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct trace_branch *field;
+
+ trace_assign_type(field, entry);
+
+ if (trace_seq_printf(s, "[%s] %s:%s:%d\n",
+ field->correct ? " ok " : " MISS ",
+ field->func,
+ field->file,
+ field->line))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return 0;
+}
+
+static struct trace_event trace_branch_event = {
+ .type = TRACE_BRANCH,
+ .trace = trace_branch_print,
+ .latency_trace = trace_branch_print,
+ .raw = trace_nop_print,
+ .hex = trace_nop_print,
+ .binary = trace_nop_print,
+};
+
struct tracer branch_trace __read_mostly =
{
.name = "branch",
@@ -154,6 +199,14 @@
__init static int init_branch_trace(void)
{
+ int ret;
+
+ ret = register_ftrace_event(&trace_branch_event);
+ if (!ret) {
+ printk(KERN_WARNING "Warning: could not register branch events\n");
+ return 1;
+ }
+
return register_tracer(&branch_trace);
}