+#ifdef ASM_SUPPORTED
+
+static __always_inline void
+__raw_read_lock_flags(raw_rwlock_t *lock, unsigned long flags)
+{
+ __asm__ __volatile__ (
+ "tbit.nz p6, p0 = %1,%2\n"
+ "br.few 3f\n"
+ "1:\n"
+ "fetchadd4.rel r2 = [%0], -1;;\n"
+ "(p6) ssm psr.i\n"
+ "2:\n"
+ "hint @pause\n"
+ "ld4 r2 = [%0];;\n"
+ "cmp4.lt p7,p0 = r2, r0\n"
+ "(p7) br.cond.spnt.few 2b\n"
+ "(p6) rsm psr.i\n"
+ ";;\n"
+ "3:\n"
+ "fetchadd4.acq r2 = [%0], 1;;\n"
+ "cmp4.lt p7,p0 = r2, r0\n"
+ "(p7) br.cond.spnt.few 1b\n"
+ : : "r"(lock), "r"(flags), "i"(IA64_PSR_I_BIT)
+ : "p6", "p7", "r2", "memory");
+}
+
+#define __raw_read_lock(lock) __raw_read_lock_flags(lock, 0)
+
+#else /* !ASM_SUPPORTED */
+
+#define __raw_read_lock_flags(rw, flags) __raw_read_lock(rw)
+