X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=urcu%2Ftls-compat.h;h=83f49fe3c896e81179c8b72c83a77486c73d89f2;hb=026057090c266aea8539f8ad1079d0ac2807de8e;hp=601336b0db6599312bf4277a668f129c8e7c1645;hpb=9948a988350a1f6564a724f79cdeb2a294ee82aa;p=urcu.git diff --git a/urcu/tls-compat.h b/urcu/tls-compat.h index 601336b..83f49fe 100644 --- a/urcu/tls-compat.h +++ b/urcu/tls-compat.h @@ -44,7 +44,7 @@ extern "C" { * typedef int my_int_array_type[4]; * DEFINE_URCU_TLS(my_int_array_type, var_name); * - * Another exmaple: + * Another example: * typedef void (*call_rcu_flavor)(struct rcu_head *, XXXX); * DECLARE_URCU_TLS(call_rcu_flavor, p_call_rcu); * @@ -70,10 +70,22 @@ extern "C" { # define DEFINE_URCU_TLS(type, name) \ CONFIG_RCU_TLS type name +# define __DEFINE_URCU_TLS_GLOBAL(type, name) \ + CONFIG_RCU_TLS type name + # define URCU_TLS(name) (name) #else /* #ifndef CONFIG_RCU_TLS */ +/* + * The *_1() macros ensure macro parameters are expanded. + * + * __DEFINE_URCU_TLS_GLOBAL and __URCU_TLS_CALL exist for the sole + * purpose of notifying applications compiled against non-fixed 0.7 and + * 0.8 userspace RCU headers and using multiple flavors concurrently to + * recompile against fixed userspace RCU headers. + */ + # include struct urcu_tls { @@ -82,15 +94,24 @@ struct urcu_tls { int init_done; }; +# define DECLARE_URCU_TLS_1(type, name) \ + type *__tls_access2_ ## name(void) + # define DECLARE_URCU_TLS(type, name) \ - type *__tls_access_ ## name(void) + DECLARE_URCU_TLS_1(type, name) /* * Note: we don't free memory at process exit, since it will be dealt * with by the OS. */ -# define DEFINE_URCU_TLS(type, name) \ - type *__tls_access_ ## name(void) \ +# define __URCU_TLS_CALL_1(name) \ + __tls_access2_ ## name + +# define __URCU_TLS_CALL(name) \ + __URCU_TLS_CALL_1(name) + +# define DEFINE_URCU_TLS_1(type, name) \ + type *__tls_access2_ ## name(void) \ { \ static struct urcu_tls __tls_ ## name = { \ .init_mutex = PTHREAD_MUTEX_INITIALIZER,\ @@ -118,7 +139,34 @@ struct urcu_tls { return __tls_p; \ } -# define URCU_TLS(name) (*__tls_access_ ## name()) +/* + * Define with and without macro expansion to handle erroneous callers. + * Trigger an abort() if the caller application uses the clashing symbol + * if a weak symbol is overridden. + */ +# define __DEFINE_URCU_TLS_GLOBAL(type, name) \ + DEFINE_URCU_TLS_1(type, name) \ + int __urcu_tls_symbol_refcount_ ## name __attribute__((weak)); \ + static __attribute__((constructor)) \ + void __urcu_tls_inc_refcount_ ## name(void) \ + { \ + __urcu_tls_symbol_refcount_ ## name++; \ + } \ + type *__tls_access_ ## name(void) \ + { \ + if (__urcu_tls_symbol_refcount_ ## name > 1) { \ + fprintf(stderr, "Error: Userspace RCU symbol clash for multiple concurrent flavors. Please upgrade liburcu libraries and headers, then recompile your application.\n"); \ + abort(); \ + } \ + return __URCU_TLS_CALL(name)(); \ + } + +# define DEFINE_URCU_TLS(type, name) \ + DEFINE_URCU_TLS_1(type, name) + +# define URCU_TLS_1(name) (*__tls_access2_ ## name()) + +# define URCU_TLS(name) URCU_TLS_1(name) #endif /* #else #ifndef CONFIG_RCU_TLS */