On 08/01/2015 10:16, Fam Zheng wrote: > Unlike ppoll(2), which accepts a timespec argument "timeout_ts" to > specify the timeout, epoll_wait(2) and epoll_pwait(2) expect a > microsecond timeout in int type. > > This is an obstacle for applications in switching from ppoll to epoll, > if they want nanosecond resolution in their event loops. > > Therefore, adding this variation of epoll wait interface, giving user an > option with *both* advantages, is a reasonable move: there could be > constantly scalable performance polling many fds, while having a > nanosecond timeout precision (assuming it has properly set up timer > slack with prctl(2)). > > Signed-off-by: Fam Zheng <famz@xxxxxxxxxx> > --- > fs/eventpoll.c | 24 ++++++++++++++++++++++++ > include/linux/syscalls.h | 4 ++++ > kernel/sys_ni.c | 3 +++ > 3 files changed, 31 insertions(+) As mentioned by Miklos in the non-resent version, please add a flags argument. Invalid flags should return -EINVAL. In fact, we could already use the flags argument to specify an absolute timeout, which is a nice thing to have for QEMU too. Paolo -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html