[PATCH v1] tracing: Be more clever when dumping hex in __print_hex()

From: Andy Shevchenko
Date: Tue Aug 06 2019 - 09:21:47 EST


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

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
kernel/trace/trace_output.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index cab4a5398f1d..ef52807473b7 100644
--- 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 % 16, 16), &buf[i]);
trace_seq_putc(p, 0);

return ret;
--
2.20.1