kmemtrace: Print binary output only if 'bin' option is set

Currently by default the output of kmemtrace is binary format instead
of human-readable output.

This patch makes the following changes:

  - We'll see human-readable output by default
  - We'll see binary output if 'bin' option is set

Note: you may probably need to explicitly disable context-info binary
      output:

	# echo 0 > options/context-info
	# echo 1 > options/bin
	# cat trace_pipe

v2:
- use %pF to print call_site

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A4DD0A0.5060500@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 90 insertions, 30 deletions

diff --git a/kernel/trace/kmemtrace.c b/kernel/trace/kmemtrace.c
index 1edaa9516e81..74903b62bcb6 100644
--- a/kernel/trace/kmemtrace.c
+++ b/kernel/trace/kmemtrace.c
@@ -239,12 +239,52 @@ struct kmemtrace_user_event_alloc {
 };
 
 static enum print_line_t
-kmemtrace_print_alloc_user(struct trace_iterator *iter,
-                           struct kmemtrace_alloc_entry *entry)
+kmemtrace_print_alloc_user(struct trace_iterator *iter, int flags)
+{
+        struct trace_seq *s = &iter->seq;
+        struct kmemtrace_alloc_entry *entry;
+        int ret;
+
+        trace_assign_type(entry, iter->ent);
+
+        ret = trace_seq_printf(s, "type_id %d call_site %pF ptr %lu "
+            "bytes_req %lu bytes_alloc %lu gfp_flags %lu node %d\n",
+            entry->type_id, (void *)entry->call_site, (unsigned long)entry->ptr,
+            (unsigned long)entry->bytes_req, (unsigned long)entry->bytes_alloc,
+            (unsigned long)entry->gfp_flags, entry->node);
+
+        if (!ret)
+                return TRACE_TYPE_PARTIAL_LINE;
+        return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+kmemtrace_print_free_user(struct trace_iterator *iter, int flags)
 {
-        struct kmemtrace_user_event_alloc *ev_alloc;
         struct trace_seq *s = &iter->seq;
+        struct kmemtrace_free_entry *entry;
+        int ret;
+
+        trace_assign_type(entry, iter->ent);
+
+        ret = trace_seq_printf(s, "type_id %d call_site %pF ptr %lu\n",
+                               entry->type_id, (void *)entry->call_site,
+                               (unsigned long)entry->ptr);
+
+        if (!ret)
+                return TRACE_TYPE_PARTIAL_LINE;
+        return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+kmemtrace_print_alloc_user_bin(struct trace_iterator *iter, int flags)
+{
+        struct trace_seq *s = &iter->seq;
+        struct kmemtrace_alloc_entry *entry;
         struct kmemtrace_user_event *ev;
+        struct kmemtrace_user_event_alloc *ev_alloc;
+
+        trace_assign_type(entry, iter->ent);
 
         ev = trace_seq_reserve(s, sizeof(*ev));
         if (!ev)
@@ -271,12 +311,14 @@ kmemtrace_print_alloc_user(struct trace_iterator *iter,
 }
 
 static enum print_line_t
-kmemtrace_print_free_user(struct trace_iterator *iter,
-                          struct kmemtrace_free_entry *entry)
+kmemtrace_print_free_user_bin(struct trace_iterator *iter, int flags)
 {
         struct trace_seq *s = &iter->seq;
+        struct kmemtrace_free_entry *entry;
         struct kmemtrace_user_event *ev;
 
+        trace_assign_type(entry, iter->ent);
+
         ev = trace_seq_reserve(s, sizeof(*ev));
         if (!ev)
                 return TRACE_TYPE_PARTIAL_LINE;
@@ -294,12 +336,14 @@ kmemtrace_print_free_user(struct trace_iterator *iter,
 
 /* The two other following provide a more minimalistic output */
 static enum print_line_t
-kmemtrace_print_alloc_compress(struct trace_iterator *iter,
-                                        struct kmemtrace_alloc_entry *entry)
+kmemtrace_print_alloc_compress(struct trace_iterator *iter)
 {
+        struct kmemtrace_alloc_entry *entry;
         struct trace_seq *s = &iter->seq;
         int ret;
 
+        trace_assign_type(entry, iter->ent);
+
         /* Alloc entry */
         ret = trace_seq_printf(s, "  +      ");
         if (!ret)
@@ -362,12 +406,14 @@ kmemtrace_print_alloc_compress(struct trace_iterator *iter,
 }
 
 static enum print_line_t
-kmemtrace_print_free_compress(struct trace_iterator *iter,
-                              struct kmemtrace_free_entry *entry)
+kmemtrace_print_free_compress(struct trace_iterator *iter)
 {
+        struct kmemtrace_free_entry *entry;
         struct trace_seq *s = &iter->seq;
         int ret;
 
+        trace_assign_type(entry, iter->ent);
+
         /* Free entry */
         ret = trace_seq_printf(s, "  -      ");
         if (!ret)
@@ -421,32 +467,31 @@ static enum print_line_t kmemtrace_print_line(struct trace_iterator *iter)
 {
         struct trace_entry *entry = iter->ent;
 
-        switch (entry->type) {
-        case TRACE_KMEM_ALLOC: {
-                struct kmemtrace_alloc_entry *field;
-
-                trace_assign_type(field, entry);
-                if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL)
-                        return kmemtrace_print_alloc_compress(iter, field);
-                else
-                        return kmemtrace_print_alloc_user(iter, field);
-        }
-
-        case TRACE_KMEM_FREE: {
-                struct kmemtrace_free_entry *field;
-
-                trace_assign_type(field, entry);
-                if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL)
-                        return kmemtrace_print_free_compress(iter, field);
-                else
-                        return kmemtrace_print_free_user(iter, field);
-        }
+        if (!(kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL))
+                return TRACE_TYPE_UNHANDLED;
 
+        switch (entry->type) {
+        case TRACE_KMEM_ALLOC:
+                return kmemtrace_print_alloc_compress(iter);
+        case TRACE_KMEM_FREE:
+                return kmemtrace_print_free_compress(iter);
         default:
                 return TRACE_TYPE_UNHANDLED;
         }
 }
 
+static struct trace_event kmem_trace_alloc = {
+        .type                   = TRACE_KMEM_ALLOC,
+        .trace                  = kmemtrace_print_alloc_user,
+        .binary                 = kmemtrace_print_alloc_user_bin,
+};
+
+static struct trace_event kmem_trace_free = {
+        .type                   = TRACE_KMEM_FREE,
+        .trace                  = kmemtrace_print_free_user,
+        .binary                 = kmemtrace_print_free_user_bin,
+};
+
 static struct tracer kmem_tracer __read_mostly = {
         .name                   = "kmemtrace",
         .init                   = kmem_trace_init,
@@ -463,6 +508,21 @@ void kmemtrace_init(void)
 
 static int __init init_kmem_tracer(void)
 {
-        return register_tracer(&kmem_tracer);
+        if (!register_ftrace_event(&kmem_trace_alloc)) {
+                pr_warning("Warning: could not register kmem events\n");
+                return 1;
+        }
+
+        if (!register_ftrace_event(&kmem_trace_free)) {
+                pr_warning("Warning: could not register kmem events\n");
+                return 1;
+        }
+
+        if (!register_tracer(&kmem_tracer)) {
+                pr_warning("Warning: could not register the kmem tracer\n");
+                return 1;
+        }
+
+        return 0;
 }
 device_initcall(init_kmem_tracer);