tls-compat.h: introduce DEFINE_URCU_TLS_INIT

DEFINE_URCU_TLS() cannot be used in this way for !CONFIG_RCU_TLS:

  DEFINE_URCU_TLS(ino_t, cached_net_ns) = NS_INO_UNINITIALIZED;

Introduce a new DEFINE_URCU_TLS_INIT which allows expressing a nonzero
intial value:

  DEFINE_URCU_TLS_INIT(ino_t, cached_net_ns, NS_INO_UNINITIALIZED);

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/include/urcu/tls-compat.h b/include/urcu/tls-compat.h
index 8ac1ea0615ddc2eb91ee51e9e15b89bd094d4c81..c17aca36b2c86a4b94f95e1c97c8aaa327f1f4a7 100644 (file)
--- a/include/urcu/tls-compat.h
+++ b/include/urcu/tls-compat.h
@@ -70,6 +70,9 @@ extern "C" {
 # define DEFINE_URCU_TLS(type, name)   \
        CONFIG_RCU_TLS type name
 
+# define DEFINE_URCU_TLS_INIT(type, name, init)        \
+       CONFIG_RCU_TLS type name = (init)
+
 # define URCU_TLS(name)                (name)
 
 #else /* #ifndef CONFIG_RCU_TLS */
@@ -95,14 +98,14 @@ struct urcu_tls {
  * Note: we don't free memory at process exit, since it will be dealt
  * with by the OS.
  */
-# define DEFINE_URCU_TLS_1(type, name)                         \
+# define DEFINE_URCU_TLS_INIT_1(type, name, do_init)           \
        type *__tls_access_ ## name(void)                       \
        {                                                       \
                static struct urcu_tls __tls_ ## name = {       \
                        .init_mutex = PTHREAD_MUTEX_INITIALIZER,\
                        .init_done = 0,                         \
                };                                              \
-               void *__tls_p;                                  \
+               __typeof__(type) *__tls_p;                      \
                if (!__tls_ ## name.init_done) {                \
                        /* Mutex to protect concurrent init */  \
                        pthread_mutex_lock(&__tls_ ## name.init_mutex); \
@@ -118,14 +121,21 @@ struct urcu_tls {
                __tls_p = pthread_getspecific(__tls_ ## name.key); \
                if (caa_unlikely(__tls_p == NULL)) {            \
                        __tls_p = calloc(1, sizeof(type));      \
+                       do_init                                 \
                        (void) pthread_setspecific(__tls_ ## name.key,  \
                                __tls_p);                       \
                }                                               \
                return __tls_p;                                 \
        }
 
+# define _URCU_TLS_INIT(init)                                  \
+       *__tls_p = (init);
+
+# define DEFINE_URCU_TLS_INIT(type, name, init)                        \
+       DEFINE_URCU_TLS_INIT_1(type, name, _URCU_TLS_INIT(init))
+
 # define DEFINE_URCU_TLS(type, name)                           \
-       DEFINE_URCU_TLS_1(type, name)
+       DEFINE_URCU_TLS_INIT_1(type, name, /* empty */)
 
 # define URCU_TLS_1(name)      (*__tls_access_ ## name())