On Tue, 23 Feb 2021 23:11:43 +0800 Eric Gao <eric.t...@foxmail.com> wrote:
> sometimes, we need the msgsnd or msgrcv syscall can return after a limited > time, so that the business thread do not be blocked here all the time. In > this case, I add the msgsnd_timed and msgrcv_timed syscall that with time > parameter, which has a unit of ms. Please cc Manfred and Davidlohr on ipc/ changes. The above is a very brief description for a new syscall! Please go to great lengths to tell us why this is considered useful - what are the use cases? Also, please fully describe the proposed syscall interface right here in the changelog. Please be prepared to later prepare a full manpage. > ... > +SYSCALL_DEFINE5(msgsnd_timed, int, msqid, struct msgbuf __user *, msgp, > size_t, msgsz, > + int, msgflg, long, timeoutms) Specifying the timeout in milliseconds is problematic - it's very coarse. See sys_epoll_pwait2()'s use of timespecs.
