trace: assign defaults at register_ftrace_event

Impact: simplification of tracers

As all tracers are doing this we might as well do it in
register_ftrace_event and save one branch each time we call these
callbacks.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 16 insertions, 13 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index fd51cf0b94c7..a5e4c0af9bb0 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1412,7 +1412,7 @@ static enum print_line_t print_lat_fmt(struct trace_iterator *iter)
                         goto partial;
         }
 
-        if (event && event->latency_trace)
+        if (event)
                 return event->latency_trace(iter, sym_flags);
 
         if (!trace_seq_printf(s, "Unknown type %d\n", entry->type))
@@ -1441,7 +1441,7 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
                         goto partial;
         }
 
-        if (event && event->trace)
+        if (event)
                 return event->trace(iter, sym_flags);
 
         if (!trace_seq_printf(s, "Unknown type %d\n", entry->type))
@@ -1467,7 +1467,7 @@ static enum print_line_t print_raw_fmt(struct trace_iterator *iter)
         }
 
         event = ftrace_find_event(entry->type);
-        if (event && event->raw)
+        if (event)
                 return event->raw(iter, 0);
 
         if (!trace_seq_printf(s, "%d ?\n", entry->type))
@@ -1494,7 +1494,7 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter)
         }
 
         event = ftrace_find_event(entry->type);
-        if (event && event->hex) {
+        if (event) {
                 enum print_line_t ret = event->hex(iter, 0);
                 if (ret != TRACE_TYPE_HANDLED)
                         return ret;
@@ -1536,10 +1536,7 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
         }
 
         event = ftrace_find_event(entry->type);
-        if (event && event->binary)
-                return event->binary(iter, 0);
-
-        return TRACE_TYPE_HANDLED;
+        return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED;
 }
 
 static int trace_empty(struct trace_iterator *iter)
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index 7ac72a44b2d3..297deb202b68 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -182,9 +182,6 @@ 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,
 };
 
 static struct tracer branch_trace __read_mostly =
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index b7380eee9fa1..b6e99af79214 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -435,6 +435,17 @@ int register_ftrace_event(struct trace_event *event)
         if (ftrace_find_event(event->type))
                 goto out;
 
+        if (event->trace == NULL)
+                event->trace = trace_nop_print;
+        if (event->latency_trace == NULL)
+                event->latency_trace = trace_nop_print;
+        if (event->raw == NULL)
+                event->raw = trace_nop_print;
+        if (event->hex == NULL)
+                event->hex = trace_nop_print;
+        if (event->binary == NULL)
+                event->binary = trace_nop_print;
+
         key = event->type & (EVENT_HASHSIZE - 1);
 
         hlist_add_head_rcu(&event->node, &event_hash[key]);
@@ -874,8 +885,6 @@ static struct trace_event trace_print_event = {
         .trace          = trace_print_print,
         .latency_trace  = trace_print_print,
         .raw            = trace_print_raw,
-        .hex            = trace_nop_print,
-        .binary         = trace_nop_print,
 };
 
 static struct trace_event *events[] __initdata = {