diff options
| author | Oleg Nesterov <oleg@tv-sign.ru> | 2006-03-28 16:11:25 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-28 18:36:44 -0800 |
| commit | 47e65328a7b1cdfc4e3102e50d60faf94ebba7d3 (patch) | |
| tree | 78e00a5321cca87767806a91e623e71b5c6637c7 /kernel | |
| parent | 88531f725bd52e37a7be726860e4ff3f09031d89 (diff) | |
| download | linux-47e65328a7b1cdfc4e3102e50d60faf94ebba7d3.tar.bz2 | |
[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')
| -rw-r--r-- | kernel/exit.c | 10 | ||||
| -rw-r--r-- | kernel/fork.c | 4 |
2 files changed, 4 insertions, 10 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index aea23e713cf4..22399caf7574 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -51,7 +51,6 @@ static void __unhash_process(struct task_struct *p) { nr_threads--; detach_pid(p, PIDTYPE_PID); - detach_pid(p, PIDTYPE_TGID); if (thread_group_leader(p)) { detach_pid(p, PIDTYPE_PGID); detach_pid(p, PIDTYPE_SID); @@ -59,7 +58,7 @@ static void __unhash_process(struct task_struct *p) list_del_init(&p->tasks); __get_cpu_var(process_counts)--; } - + list_del_rcu(&p->thread_group); remove_parent(p); } @@ -964,13 +963,6 @@ asmlinkage long sys_exit(int error_code) do_exit((error_code&0xff)<<8); } -task_t fastcall *next_thread(const task_t *p) -{ - return pid_task(p->pids[PIDTYPE_TGID].pid_list.next, PIDTYPE_TGID); -} - -EXPORT_SYMBOL(next_thread); - /* * Take down every thread in the group. This is called by fatal signals * as well as by sys_exit_group (below). 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++; } |