From 4717bfec708d264111f70f37850ffc09238c4bd5 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Tue, 2 Aug 2011 21:18:43 -0400 Subject: [PATCH] correctly handle old kernels without FUTEX_WAIT_BITSET futex returns EINVAL, not ENOSYS, when op is not supported. unfortunately this looks just like EINVAL from other causes, and we end up running the fallback code and getting EINVAL again. fortunately this case should be rare since correct code should not generate EINVAL anyway. --- src/thread/__timedwait.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/thread/__timedwait.c b/src/thread/__timedwait.c index 931675eb..0444d39f 100644 --- a/src/thread/__timedwait.c +++ b/src/thread/__timedwait.c @@ -16,7 +16,7 @@ static int do_wait(volatile int *addr, int val, clockid_t clk, const struct time if (clk == CLOCK_REALTIME) flag = FUTEX_CLOCK_REALTIME; if (cp) r = -__syscall_cp(SYS_futex, addr, FUTEX_WAIT_BITSET|flag, val, at, 0, -1); else r = -__syscall(SYS_futex, addr, FUTEX_WAIT_BITSET|flag, val, at, 0, -1); - if (r != ENOSYS) goto done; + if (r != EINVAL) goto done; } if (clock_gettime(clk, &to)) return EINVAL; to.tv_sec = at->tv_sec - to.tv_sec; -- 2.20.1