AH_TEMPLATE([CONFIG_RCU_ARM_HAVE_DMB], [Use the dmb instruction if available for use on ARM.])
AH_TEMPLATE([CONFIG_RCU_TLS], [TLS provided by the compiler.])
-AX_TLS(AC_DEFINE_UNQUOTED([CONFIG_RCU_TLS], $ac_cv_tls), [:])
+# Allow overriding storage used for TLS variables.
+AC_ARG_ENABLE([compiler-tls],
+ AS_HELP_STRING([--disable-compiler-tls], [Use pthread_getspecific() to emulate Thread Local Storage (TLS) variables.]),
+ [def_compiler_tls=$enableval],
+ [def_compiler_tls="yes"])
+
+# If not overridden, use ax_tls.m4 to check if TLS is available.
+AS_IF([test "x$def_compiler_tls" = "xyes"],
+ [AX_TLS([def_tls_detect=$ac_cv_tls], [:])],
+ [:])
+
+AS_IF([test "x$def_tls_detect" = "x"],
+ [:],
+ [AC_DEFINE_UNQUOTED([CONFIG_RCU_TLS], $def_tls_detect)])
# Checks for programs.
AC_PROG_CC
[ia64], [ARCHTYPE="gcc"],
[arm*], [ARCHTYPE="arm"],
[mips*], [ARCHTYPE="mips"],
+ [tile*], [ARCHTYPE="tile"],
[ARCHTYPE="unknown"]
)
],[
AS_ECHO("SMP support disabled.")
])
+
+AS_IF([test "x$def_tls_detect" = "x"],[
+ AS_ECHO("Thread Local Storage (TLS): pthread_getspecific().")
+],[
+ AS_ECHO("Thread Local Storage (TLS): $def_tls_detect.")
+])