Messages in this thread | | | Date | Mon, 26 Oct 2015 15:10:27 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH 3/3] sched: Implement interface for cgroup unified hierarchy |
| |
On Sun, Oct 25, 2015 at 02:17:23PM +0100, Florian Weimer wrote: > On 10/25/2015 12:58 PM, Theodore Ts'o wrote: > > > Well, I was thinking we could just teach them to use > > "syscall(SYS_gettid)". > > Right, and that's easier if TIDs are officially part of the GNU API. > > I think the worry is that some future system might have TIDs which do > not share the PID space, or are real descriptors (that they need > explicit open and close operations).
For the scheduler the sharing of pid/tid space is not an issue.
Semantically all [1] scheduler syscalls take a tid. There isn't a single syscall that iterates the thread group.
Even sys_setpriority() interprets its @who argument as a tid when @which == PRIO_PROCESS (PRIO_PGRP looks to be the actual process).
[1] as seen from: git grep SYSCALL kernel/sched/
| |