• Oleg Nesterov's avatar
    [PATCH] pids: kill PIDTYPE_TGID · 47e65328
    Oleg Nesterov authored
    This patch kills PIDTYPE_TGID pid_type thus saving one hash table in
    kernel/pid.c and speeding up subthreads create/destroy a bit.  It is also a
    preparation for the further tref/pids rework.
    This patch adds 'struct list_head thread_group' to 'struct task_struct'
    We don't detach group leader from PIDTYPE_PID namespace until another
    thread inherits it's ->pid == ->tgid, so we are safe wrt premature
    free_pidmap(->tgid) call.
    Currently there are no users of find_task_by_pid_type(PIDTYPE_TGID).
    Should the need arise, we can use find_task_by_pid()->group_leader.
    Signed-off-by: default avatarOleg Nesterov <oleg@tv-sign.ru>
    Acked-By: default avatarEric Biederman <ebiederm@xmission.com>
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
fork.c 39.9 KB