[PATCH] proc: Remove tasklist_lock from proc_pid_lookup() and proc_task_lookup()

Since we no longer need the tasklist_lock for get_task_struct the lookup
methods no longer need the tasklist_lock.

This just depends on my previous patch that makes get_task_struct() rcu
safe.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/proc/base.c b/fs/proc/base.c
index cc578a300a2b668f47ad8709e12ee9fbb354f69c..8180579f879214b1476d53dc71424128cb64f69f 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1940,11 +1940,11 @@ struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct
        if (tgid == ~0U)
                goto out;
 
-       read_lock(&tasklist_lock);
+       rcu_read_lock();
        task = find_task_by_pid(tgid);
        if (task)
                get_task_struct(task);
-       read_unlock(&tasklist_lock);
+       rcu_read_unlock();
        if (!task)
                goto out;
 
@@ -1988,11 +1988,11 @@ static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry
        if (tid == ~0U)
                goto out;
 
-       read_lock(&tasklist_lock);
+       rcu_read_lock();
        task = find_task_by_pid(tid);
        if (task)
                get_task_struct(task);
-       read_unlock(&tasklist_lock);
+       rcu_read_unlock();
        if (!task)
                goto out;
        if (leader->tgid != task->tgid)