path: root/kernel/ptrace.c
diff options
authorOleg Nesterov <oleg@redhat.com>2009-06-17 16:27:34 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-18 13:03:51 -0700
commit8053bdd5ce15dcf043d41a4dd6cac4a5567effdc (patch)
treeb139a0763d46143fbe5e36811b03c1987ef23b7a /kernel/ptrace.c
parent4b105cbbaf7c06e01c27391957dc3c446328d087 (diff)
ptrace_get_task_struct: s/tasklist/rcu/, make it static
- Use rcu_read_lock() instead of tasklist_lock to find/get the task in ptrace_get_task_struct(). - Make it static, it has no callers outside of ptrace.c. - The comment doesn't match the reality, this helper does not do any checks. Beacuse it is really trivial and static I removed the whole comment. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/ptrace.c')
1 files changed, 3 insertions, 13 deletions
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 38fdfea1a15..a64fe75a48b 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -581,26 +581,16 @@ int ptrace_request(struct task_struct *child, long request,
return ret;
- * ptrace_get_task_struct -- grab a task struct reference for ptrace
- * @pid: process id to grab a task_struct reference of
- *
- * This function is a helper for ptrace implementations. It checks
- * permissions and then grabs a task struct for use of the actual
- * ptrace implementation.
- *
- * Returns the task_struct for @pid or an ERR_PTR() on failure.
- */
-struct task_struct *ptrace_get_task_struct(pid_t pid)
+static struct task_struct *ptrace_get_task_struct(pid_t pid)
struct task_struct *child;
- read_lock(&tasklist_lock);
+ rcu_read_lock();
child = find_task_by_vpid(pid);
if (child)
+ rcu_read_unlock();
- read_unlock(&tasklist_lock);
if (!child)
return ERR_PTR(-ESRCH);
return child;