tracing: Convert trace_printk() formats for module to const char *

The trace_printk() formats for modules do not show up in the
debugfs/tracing/printk_formats file. Only the formats that are
for trace_printk()s that are in the kernel core.

To facilitate the change to add trace_printk() formats from modules
into that file as well, we need to convert the structure that
holds the formats from char fmt[], into const char *fmt,
and allocate them separately.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 2547d8813cf0535048162db1d986263a638f188a..b8b268158af0657a8ecc02e03b8407a7f8b26f23 100644 (file)
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -32,7 +32,7 @@ static DEFINE_MUTEX(btrace_mutex);
 
 struct trace_bprintk_fmt {
        struct list_head list;
-       char fmt[0];
+       const char *fmt;
 };
 
 static inline struct trace_bprintk_fmt *lookup_format(const char *fmt)
@@ -49,6 +49,7 @@ static
 void hold_module_trace_bprintk_format(const char **start, const char **end)
 {
        const char **iter;
+       char *fmt;
 
        mutex_lock(&btrace_mutex);
        for (iter = start; iter < end; iter++) {
@@ -58,14 +59,18 @@ void hold_module_trace_bprintk_format(const char **start, const char **end)
                        continue;
                }
 
-               tb_fmt = kmalloc(offsetof(struct trace_bprintk_fmt, fmt)
-                               + strlen(*iter) + 1, GFP_KERNEL);
-               if (tb_fmt) {
+               tb_fmt = kmalloc(sizeof(*tb_fmt), GFP_KERNEL);
+               if (tb_fmt)
+                       fmt = kmalloc(strlen(*iter) + 1, GFP_KERNEL);
+               if (tb_fmt && fmt) {
                        list_add_tail(&tb_fmt->list, &trace_bprintk_fmt_list);
-                       strcpy(tb_fmt->fmt, *iter);
+                       strcpy(fmt, *iter);
+                       tb_fmt->fmt = fmt;
                        *iter = tb_fmt->fmt;
-               } else
+               } else {
+                       kfree(tb_fmt);
                        *iter = NULL;
+               }
        }
        mutex_unlock(&btrace_mutex);
 }