diff options
author | Oleg Nesterov <oleg@tv-sign.ru> | 2006-03-29 02:11:25 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-29 04:36:44 +0200 |
commit | 47e65328a7b1cdfc4e3102e50d60faf94ebba7d3 (patch) | |
tree | 78e00a5321cca87767806a91e623e71b5c6637c7 /kernel/fork.c | |
parent | [PATCH] do_sigaction: don't take tasklist_lock (diff) | |
download | linux-47e65328a7b1cdfc4e3102e50d60faf94ebba7d3.tar.xz linux-47e65328a7b1cdfc4e3102e50d60faf94ebba7d3.zip |
[PATCH] pids: kill PIDTYPE_TGID
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'
instead.
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: Oleg Nesterov <oleg@tv-sign.ru>
Acked-By: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel/fork.c')
-rw-r--r-- | kernel/fork.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 12cdd9fc9d02..bc551efb5fd4 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1112,6 +1112,7 @@ static task_t *copy_process(unsigned long clone_flags, * We dont wake it up yet. */ p->group_leader = p; + INIT_LIST_HEAD(&p->thread_group); INIT_LIST_HEAD(&p->ptrace_children); INIT_LIST_HEAD(&p->ptrace_list); @@ -1165,7 +1166,9 @@ static task_t *copy_process(unsigned long clone_flags, retval = -EAGAIN; goto bad_fork_cleanup_namespace; } + p->group_leader = current->group_leader; + list_add_tail_rcu(&p->thread_group, &p->group_leader->thread_group); if (current->signal->group_stop_count > 0) { /* @@ -1213,7 +1216,6 @@ static task_t *copy_process(unsigned long clone_flags, list_add_tail(&p->tasks, &init_task.tasks); __get_cpu_var(process_counts)++; } - attach_pid(p, PIDTYPE_TGID, p->tgid); attach_pid(p, PIDTYPE_PID, p->pid); nr_threads++; } |