X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Fexit.c;h=7f2683a10ac40d2682a4a400091ec61bd2131739;hb=46da27664887fb95cedba53eafcf876de812c8c1;hp=5962d7ccf24371ed7aedf4832cac0cbd5e9c3820;hpb=1d615482547584b9a8bb6316a58fed6ce90dd9ff;p=safe%2Fjmp%2Flinux-2.6

diff --git a/kernel/exit.c b/kernel/exit.c
index 5962d7c..7f2683a 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -68,10 +68,10 @@ static void __unhash_process(struct task_struct *p)
 		detach_pid(p, PIDTYPE_SID);
 
 		list_del_rcu(&p->tasks);
+		list_del_init(&p->sibling);
 		__get_cpu_var(process_counts)--;
 	}
 	list_del_rcu(&p->thread_group);
-	list_del_init(&p->sibling);
 }
 
 /*
@@ -85,7 +85,9 @@ static void __exit_signal(struct task_struct *tsk)
 	BUG_ON(!sig);
 	BUG_ON(!atomic_read(&sig->count));
 
-	sighand = rcu_dereference(tsk->sighand);
+	sighand = rcu_dereference_check(tsk->sighand,
+					rcu_read_lock_held() ||
+					lockdep_tasklist_lock_is_held());
 	spin_lock(&sighand->siglock);
 
 	posix_cpu_timers_exit(tsk);
@@ -170,8 +172,10 @@ void release_task(struct task_struct * p)
 repeat:
 	tracehook_prepare_release_task(p);
 	/* don't need to get the RCU readlock here - the process is dead and
-	 * can't be modifying its own credentials */
+	 * can't be modifying its own credentials. But shut RCU-lockdep up */
+	rcu_read_lock();
 	atomic_dec(&__task_cred(p)->user->processes);
+	rcu_read_unlock();
 
 	proc_flush_task(p);
 
@@ -473,9 +477,11 @@ static void close_files(struct files_struct * files)
 	/*
 	 * It is safe to dereference the fd table without RCU or
 	 * ->file_lock because this is the last reference to the
-	 * files structure.
+	 * files structure.  But use RCU to shut RCU-lockdep up.
 	 */
+	rcu_read_lock();
 	fdt = files_fdtable(files);
+	rcu_read_unlock();
 	for (;;) {
 		unsigned long set;
 		i = j * __NFDBITS;
@@ -521,10 +527,12 @@ void put_files_struct(struct files_struct *files)
 		 * at the end of the RCU grace period. Otherwise,
 		 * you can free files immediately.
 		 */
+		rcu_read_lock();
 		fdt = files_fdtable(files);
 		if (fdt != &files->fdtab)
 			kmem_cache_free(files_cachep, files);
 		free_fdtable(fdt);
+		rcu_read_unlock();
 	}
 }
 
@@ -736,12 +744,9 @@ static struct task_struct *find_new_reaper(struct task_struct *father)
 /*
 * Any that need to be release_task'd are put on the @dead list.
  */
-static void reparent_thread(struct task_struct *father, struct task_struct *p,
+static void reparent_leader(struct task_struct *father, struct task_struct *p,
 				struct list_head *dead)
 {
-	if (p->pdeath_signal)
-		group_send_sig_info(p->pdeath_signal, SEND_SIG_NOINFO, p);
-
 	list_move_tail(&p->sibling, &p->real_parent->children);
 
 	if (task_detached(p))
@@ -780,12 +785,18 @@ static void forget_original_parent(struct task_struct *father)
 	reaper = find_new_reaper(father);
 
 	list_for_each_entry_safe(p, n, &father->children, sibling) {
-		p->real_parent = reaper;
-		if (p->parent == father) {
-			BUG_ON(task_ptrace(p));
-			p->parent = p->real_parent;
-		}
-		reparent_thread(father, p, &dead_children);
+		struct task_struct *t = p;
+		do {
+			t->real_parent = reaper;
+			if (t->parent == father) {
+				BUG_ON(task_ptrace(t));
+				t->parent = t->real_parent;
+			}
+			if (t->pdeath_signal)
+				group_send_sig_info(t->pdeath_signal,
+						    SEND_SIG_NOINFO, t);
+		} while_each_thread(p, t);
+		reparent_leader(father, p, &dead_children);
 	}
 	write_unlock_irq(&tasklist_lock);
 
@@ -941,7 +952,9 @@ NORET_TYPE void do_exit(long code)
 				preempt_count());
 
 	acct_update_integrals(tsk);
-
+	/* sync mm's RSS info before statistics gathering */
+	if (tsk->mm)
+		sync_mm_rss(tsk, tsk->mm);
 	group_dead = atomic_dec_and_test(&tsk->signal->live);
 	if (group_dead) {
 		hrtimer_cancel(&tsk->signal->real_timer);
@@ -1177,7 +1190,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
 
 	if (unlikely(wo->wo_flags & WNOWAIT)) {
 		int exit_code = p->exit_code;
-		int why, status;
+		int why;
 
 		get_task_struct(p);
 		read_unlock(&tasklist_lock);
@@ -1551,14 +1564,9 @@ static int do_wait_thread(struct wait_opts *wo, struct task_struct *tsk)
 	struct task_struct *p;
 
 	list_for_each_entry(p, &tsk->children, sibling) {
-		/*
-		 * Do not consider detached threads.
-		 */
-		if (!task_detached(p)) {
-			int ret = wait_consider_task(wo, 0, p);
-			if (ret)
-				return ret;
-		}
+		int ret = wait_consider_task(wo, 0, p);
+		if (ret)
+			return ret;
 	}
 
 	return 0;