Hosts the 0x221E linux distro kernel. https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-rolling-stable 2021-01-12T01:52:40Z 2021-01-12T01:52:40Z Guo Ren guoren@linux.alibaba.com 2020-12-20T01:35:09Z urn:sha1:d6c5cb9f8c7584e961a5b04fa2553659e1b2cce7 Arnd said: I would guess that for csky, this is a mistake, as the architecture is fairly new and should be able to implement it. Guo reply: The c610, c807, c810 don't support SMP, so futex_cmpxchg_enabled = 1 with asm-generic's implementation. For c860, there is no HAVE_FUTEX_CMPXCHG and cmpxchg_inatomic/inuser implementation, so futex_cmpxchg_enabled = 0. Thx for point it out, we'll implement cmpxchg_inatomic/inuser for C860 and still use asm-generic for non-smp CPUs. LTP test: futex_wait01 1 TPASS : futex_wait(): errno=ETIMEDOUT(110): Connection timed out futex_wait01 2 TPASS : futex_wait(): errno=EAGAIN/EWOULDBLOCK(11): Resource temporarily unavailable futex_wait01 3 TPASS : futex_wait(): errno=ETIMEDOUT(110): Connection timed out futex_wait01 4 TPASS : futex_wait(): errno=EAGAIN/EWOULDBLOCK(11): Resource temporarily unavailable futex_wait02 1 TPASS : futex_wait() woken up futex_wait03 1 TPASS : futex_wait() woken up futex_wait04 1 TPASS : futex_wait() returned -1: errno=EAGAIN/EWOULDBLOCK(11): Resource temporarily unavailable Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Cc: Arnd Bergmann <arnd@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/lkml/CAK8P3a3+WaQNyJ6Za2qfu6=0mBgU1hApnRXrdp1b1=P7wwyRUg@mail.gmail.com/