Let's jump in and share more thoughts... :) On Tue, Jul 20, 2010 at 12:16, Aiolia Lea <casmyu@xxxxxxxxx> wrote: > Hi, > > 1) If the user space process has existed, why the kernel still need to store > a reference to it? Because kernel still needs to access it? > 2) From <understanding the linux kernel> 3rd edition, I found one pid > structure can be corresponded to multi pid_t, and if we want to look up one > task_struct by pid_t, we need to use a PID hash table. Honestly, I am > confused by this flow. Actually, this "messy flow" is due to introduction of pid namespace and threading stuffs. Pid namespace, like the one you see in linux-vserver etc makes you able to create different processes in different guest (or let's say "realm") with same pid according to their own realm. Threading makes you share "real" pid, but actually they have their own thread ID ...at least that's what I recall on top of my head. -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
