On 11/24, Eric W. Biederman wrote: > > Oleg Nesterov <[email protected]> writes: > > > Eric, Pavel, could you review 1/2 ? (documentation only). It is based on the > > code inspection, I didn't bother to verify that my understanding matches the > > reality ;) > > > > On 11/20, Oleg Nesterov wrote: > >> > >> > >> Probably this is not the last series... in particular it seems that we > >> have some problems with sys_setns() in this area, but I need to recheck. > > > > So far only the documentation fix. I'll write another email (hopefully with > > the > > patch), afaics at least setns() doesn't play well with > > PR_SET_CHILD_SUBREAPER. > > > > Contrary to what I thought zap_pid_ns_processes() looks fine, but it seems > > only > > by accident. Unless I am totally confused, wait for "nr_hashed == init_pids" > > could be removed after 0a01f2cc390e10633a "pidns: Make the pidns proc mount/ > > umount logic obvious". However, now that setns() + fork() can inject a task > > into a child namespace, we need this code again for another reason. > > > > I _think_ we can actually remove it and simplify free_pid() as well, but > > lets > > discuss this later and fix the wrong/confusing documentation first. > > At the very least there is the issue of rusage being wrong if we allow > the init process to be reaped before all of it's children are reaped.
Do you mean cstime/cutime/c* accounting? Firstly it is not clear what makes child_reaper special in _this_ sense, but this doesn't matter at all. The auotoreaping/EXIT_DEAD children are not accounted, only wait_task_zombie() accumulates these counters. (just in case, accounting in __exit_signal() is another thing). > There is also a huge level of weird non-intuitive behavior that would > require some substantial benefits to justify an optimization of letting > a child exist longer than init. Sure. That is why I said "lets discuss this later". This patch doesn't try to change the rules. It only tries to document the current code. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
