From 7e49827cc937a742ae02078b483e3eb78f791a2a Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Wed, 26 May 2010 14:43:22 -0700 Subject: [PATCH] proc: get_nr_threads() doesn't need ->siglock any longer Now that task->signal can't go away get_nr_threads() doesn't need ->siglock to read signal->count. Also, make it inline, move into sched.h, and convert 2 other proc users of signal->count to use this (now trivial) helper. Henceforth get_nr_threads() is the only valid user of signal->count, we are ready to turn it into "int nr_threads" or, perhaps, kill it. Signed-off-by: Oleg Nesterov Cc: Alexey Dobriyan Cc: David Howells Cc: "Eric W. Biederman" Acked-by: Roland McGrath Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/array.c | 4 ++-- fs/proc/base.c | 12 ------------ include/linux/sched.h | 5 +++++ 3 files changed, 7 insertions(+), 14 deletions(-) diff --git a/fs/proc/array.c b/fs/proc/array.c index 885ab5513ac5..9b58d38bc911 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -267,7 +267,7 @@ static inline void task_sig(struct seq_file *m, struct task_struct *p) shpending = p->signal->shared_pending.signal; blocked = p->blocked; collect_sigign_sigcatch(p, &ignored, &caught); - num_threads = atomic_read(&p->signal->count); + num_threads = get_nr_threads(p); rcu_read_lock(); /* FIXME: is this correct? */ qsize = atomic_read(&__task_cred(p)->user->sigpending); rcu_read_unlock(); @@ -410,7 +410,7 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns, tty_nr = new_encode_dev(tty_devnum(sig->tty)); } - num_threads = atomic_read(&sig->count); + num_threads = get_nr_threads(task); collect_sigign_sigcatch(task, &sigign, &sigcatch); cmin_flt = sig->cmin_flt; diff --git a/fs/proc/base.c b/fs/proc/base.c index c7f9f23449dc..c384e8b84dff 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -166,18 +166,6 @@ static int get_fs_path(struct task_struct *task, struct path *path, bool root) return result; } -static int get_nr_threads(struct task_struct *tsk) -{ - unsigned long flags; - int count = 0; - - if (lock_task_sighand(tsk, &flags)) { - count = atomic_read(&tsk->signal->count); - unlock_task_sighand(tsk, &flags); - } - return count; -} - static int proc_cwd_link(struct inode *inode, struct path *path) { struct task_struct *task = get_proc_task(inode); diff --git a/include/linux/sched.h b/include/linux/sched.h index dd597d8013a8..ccd2d1500720 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2147,6 +2147,11 @@ extern bool current_is_single_threaded(void); #define while_each_thread(g, t) \ while ((t = next_thread(t)) != g) +static inline int get_nr_threads(struct task_struct *tsk) +{ + return atomic_read(&tsk->signal->count); +} + /* de_thread depends on thread_group_leader not being a pid based check */ #define thread_group_leader(p) (p == p->group_leader) -- 2.39.2