tracing: Be more clever when dumping hex in __print_hex()

Hex dump as many as 16 bytes at once in trace_print_hex_seq()
instead of byte-by-byte approach.

Link: http://lkml.kernel.org/r/20190806151543.86061-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index cab4a53..d54ce25 100644 (file)
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -219,10 +219,10 @@ trace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len,
 {
        int i;
        const char *ret = trace_seq_buffer_ptr(p);
+       const char *fmt = concatenate ? "%*phN" : "%*ph";
 
-       for (i = 0; i < buf_len; i++)
-               trace_seq_printf(p, "%s%2.2x", concatenate || i == 0 ? "" : " ",
-                                buf[i]);
+       for (i = 0; i < buf_len; i += 16)
+               trace_seq_printf(p, fmt, min(buf_len - i, 16), &buf[i]);
        trace_seq_putc(p, 0);
 
        return ret;