On Mon, Jan 08, 2018 at 09:23:49AM -0800, Dave Hansen wrote: > On 01/08/2018 09:17 AM, Willy Tarreau wrote: > >> I think the prctl() should apply to an entire process, not to a thread. > > > > As I mentionned in another mail, I didn't know how to do it, even less > > how to do it fast enough so that we didn't add more cycles to the syscall > > code. > > You can _implement_ it with a task thread if you want. Just spray it > across all threads at the prctl()-time instead of a single thread. > It'll take a wee bit of locking. > > I just don't think the API should apply to a single thread.
It is surprisingly hard to find all tasks that share an mm. Finding all threads in a threadgroup is easy, but we have CLONE_THREAD and CLONE_VM as separate bits. In any case, aside from that, setting this remotely is indeed 'intersting'.
