From 709f86057db2cba4e723730567ee1bd1244cf21e Mon Sep 17 00:00:00 2001
From: Adam Sutton <dev@adamsutton.me.uk>
Date: Tue, 3 Sep 2013 23:14:31 +0100
Subject: [PATCH] tvhlog: performance improvement when trace/debug is disabled.

The processing performed in the hexdump routine, commonly used in
SI table trace output. Was having a significant impact on performance
as it was not pre-processing the config to see if trace was even
enabled before continuing to build up the (large and frequent) hex
strings.
---
 src/tvhlog.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/tvhlog.c b/src/tvhlog.c
index fca5c0c7..219cacaa 100644
--- a/src/tvhlog.c
+++ b/src/tvhlog.c
@@ -243,7 +243,7 @@ void tvhlogv ( const char *file, int line,
   int ok, options;
   size_t l;
   char buf[1024];
-  
+
   /* Check debug enabled (and cache config) */
   pthread_mutex_lock(&tvhlog_mutex);
   options = tvhlog_options;
@@ -319,9 +319,16 @@ _tvhlog_hexdump(const char *file, int line,
                 const char *subsys,
                 const uint8_t *data, ssize_t len )
 {
-  int i, c;
+  int i, c, skip;
   char str[1024];
 
+  /* Don't process if trace is OFF */
+  pthread_mutex_lock(&tvhlog_mutex);
+  skip = (severity > tvhlog_level);
+  pthread_mutex_unlock(&tvhlog_mutex);
+  if (skip) return;
+ 
+  /* Build and log output */
   while (len > 0) {
     c = 0;
     for (i = 0; i < HEXDUMP_WIDTH; i++) {