[lxc-devel] [PATCH] put shared variables into thread-local storage

[S.Çağlar Onur]

This doesn't solve the general design problem of the log.c (eg; some log lines
got lost or scattered into multiple files) but at least prevent multithreaded
code from crashing.

Before this change something like following;

sudo src/tests/lxc-test-concurrent -i 10 -j 20

was crashing nearly all the time due to 3afbcc4600a as we started to
set lxc.loglevel and lxc.logfile with that commit.

Signed-off-by: S.Çağlar Onur <caglar at 10ur.org>
---
 src/lxc/log.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/lxc/log.c b/src/lxc/log.c
index 2f880e2..1dd1aa8 100644
--- a/src/lxc/log.c
+++ b/src/lxc/log.c
@@ -41,6 +41,15 @@
 #define LXC_LOG_BUFFER_SIZE	512
 
 int lxc_log_fd = -1;
+#ifdef HAVE_TLS
+static __thread char log_prefix[LXC_LOG_PREFIX_SIZE] = "lxc";
+static __thread char *log_fname = NULL;
+/* command line values for logfile or logpriority should always override
+ * values from the configuration file or defaults
+ */
+static __thread int lxc_logfile_specified = 0;
+static __thread int lxc_loglevel_specified = 0;
+#else
 static char log_prefix[LXC_LOG_PREFIX_SIZE] = "lxc";
 static char *log_fname = NULL;
 /* command line values for logfile or logpriority should always override
@@ -48,6 +57,7 @@ static char *log_fname = NULL;
  */
 static int lxc_logfile_specified = 0;
 static int lxc_loglevel_specified = 0;
+#endif
 
 lxc_log_define(lxc_log, lxc);
 
-- 
1.8.3.2