tracing/core: drop the old trace_printk() implementation in favour of trace_bprintk()

Impact: faster and lighter tracing

Now that we have trace_bprintk() which is faster and consume lesser
memory than trace_printk() and has the same purpose, we can now drop
the old implementation in favour of the binary one from trace_bprintk(),
which means we move all the implementation of trace_bprintk() to
trace_printk(), so the Api doesn't change except that we must now use
trace_seq_bprintk() to print the TRACE_PRINT entries.

Some changes result of this:

- Previously, trace_bprintk depended of a single tracer and couldn't
  work without. This tracer has been dropped and the whole implementation
  of trace_printk() (like the module formats management) is now integrated
  in the tracing core (comes with CONFIG_TRACING), though we keep the file
  trace_printk (previously trace_bprintk.c) where we can find the module
  management. Thus we don't overflow trace.c

- changes some parts to use trace_seq_bprintk() to print TRACE_PRINT entries.

- change a bit trace_printk/trace_vprintk macros to support non-builtin formats
  constants, and fix 'const' qualifiers warnings. But this is all transparent for
  developers.

- etc...

V2:

- Rebase against last changes
- Fix mispell on the changelog

V3:

- Rebase against last changes (moving trace_printk() to kernel.h)

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1236356510-8381-5-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 12 insertions, 58 deletions

diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 4ab71201862e..ef8fd661b217 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -53,8 +53,7 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
         return len;
 }
 
-static int
-trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
+int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
 {
         int len = (PAGE_SIZE - 1) - s->len;
         int ret;
@@ -834,54 +833,12 @@ static struct trace_event trace_user_stack_event = {
 };
 
 /* TRACE_PRINT */
-static enum print_line_t trace_print_print(struct trace_iterator *iter,
-                                           int flags)
-{
-        struct print_entry *field;
-        struct trace_seq *s = &iter->seq;
-
-        trace_assign_type(field, iter->ent);
-
-        if (!seq_print_ip_sym(s, field->ip, flags))
-                goto partial;
-
-        if (!trace_seq_printf(s, ": %s", field->buf))
-                goto partial;
-
-        return TRACE_TYPE_HANDLED;
-
- partial:
-        return TRACE_TYPE_PARTIAL_LINE;
-}
-
-static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags)
-{
-        struct print_entry *field;
-
-        trace_assign_type(field, iter->ent);
-
-        if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
-                goto partial;
-
-        return TRACE_TYPE_HANDLED;
-
- partial:
-        return TRACE_TYPE_PARTIAL_LINE;
-}
-
-static struct trace_event trace_print_event = {
-        .type           = TRACE_PRINT,
-        .trace          = trace_print_print,
-        .raw            = trace_print_raw,
-};
-
-/* TRACE_BPRINTK */
 static enum print_line_t
-trace_bprintk_print(struct trace_iterator *iter, int flags)
+trace_print_print(struct trace_iterator *iter, int flags)
 {
         struct trace_entry *entry = iter->ent;
         struct trace_seq *s = &iter->seq;
-        struct bprintk_entry *field;
+        struct print_entry *field;
 
         trace_assign_type(field, entry);
 
@@ -900,14 +857,13 @@ trace_bprintk_print(struct trace_iterator *iter, int flags)
         return TRACE_TYPE_PARTIAL_LINE;
 }
 
-static enum print_line_t
-trace_bprintk_raw(struct trace_iterator *iter, int flags)
+
+static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags)
 {
-        struct trace_entry *entry = iter->ent;
+        struct print_entry *field;
         struct trace_seq *s = &iter->seq;
-        struct bprintk_entry *field;
 
-        trace_assign_type(field, entry);
+        trace_assign_type(field, iter->ent);
 
         if (!trace_seq_printf(s, ": %lx : ", field->ip))
                 goto partial;
@@ -921,12 +877,11 @@ trace_bprintk_raw(struct trace_iterator *iter, int flags)
         return TRACE_TYPE_PARTIAL_LINE;
 }
 
-static struct trace_event trace_bprintk_event = {
-        .type           = TRACE_BPRINTK,
-        .trace          = trace_bprintk_print,
-        .raw            = trace_bprintk_raw,
-        .hex            = trace_nop_print,
-        .binary         = trace_nop_print,
+
+static struct trace_event trace_print_event = {
+        .type           = TRACE_PRINT,
+        .trace          = trace_print_print,
+        .raw            = trace_print_raw,
 };
 
 static struct trace_event *events[] __initdata = {
@@ -937,7 +892,6 @@ static struct trace_event *events[] __initdata = {
         &trace_stack_event,
         &trace_user_stack_event,
         &trace_print_event,
-        &trace_bprintk_event,
         NULL
 };