X-Git-Url: https://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=urcu%2Ffutex.h;h=0486ff6a1830f174d7471164a282507a6d1f756c;hp=4d16cfa5201453954dc7e6233372ea6969d23c26;hb=b2633d211b186cb201be327ded53ecf523ecf0bd;hpb=67ecffc0f530a7b5c4dd5111ea7dd3213da8eb91

diff --git a/urcu/futex.h b/urcu/futex.h
index 4d16cfa..0486ff6 100644
--- a/urcu/futex.h
+++ b/urcu/futex.h
@@ -73,7 +73,16 @@ static inline int futex_noasync(int32_t *uaddr, int op, int32_t val,
 
 	ret = futex(uaddr, op, val, timeout, uaddr2, val3);
 	if (caa_unlikely(ret < 0 && errno == ENOSYS)) {
-		return compat_futex_noasync(uaddr, op, val, timeout,
+		/*
+		 * The fallback on ENOSYS is the async-safe version of
+		 * the compat futex implementation, because the
+		 * async-safe compat implementation allows being used
+		 * concurrently with calls to futex(). Indeed, sys_futex
+		 * FUTEX_WAIT, on some architectures (mips and parisc),
+		 * within a given process, spuriously return ENOSYS due
+		 * to signal restart bugs on some kernel versions.
+		 */
+		return compat_futex_async(uaddr, op, val, timeout,
 				uaddr2, val3);
 	}
 	return ret;