Merge "lowmemorykiller: use for_each_thread instead of buggy while_each_thread" (0457fb48) · Commits · e / devices / android_kernel_sony_msm8994

drivers/staging/android/lowmemorykiller.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -79,16 +79,16 @@ static unsigned long lowmem_deathpending_timeout;

		static int test_task_flag(struct task_struct *p, int flag)
		{
		struct task_struct *t = p;
		struct task_struct *t;

		do {
		for_each_thread(p, t) {
		task_lock(t);
		if (test_tsk_thread_flag(t, flag)) {
		task_unlock(t);
		return 1;
		}
		task_unlock(t);
		} while_each_thread(p, t);
		}

		return 0;
		}

include/linux/init_task.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -40,6 +40,7 @@ extern struct fs_struct init_fs;

		#define INIT_SIGNALS(sig) { \
		.nr_threads = 1, \
		.thread_head = LIST_HEAD_INIT(init_task.thread_node), \
		.wait_chldexit = __WAIT_QUEUE_HEAD_INITIALIZER(sig.wait_chldexit),\
		.shared_pending = { \
		.list = LIST_HEAD_INIT(sig.shared_pending.list), \
		@@ -213,6 +214,7 @@ extern struct task_group root_task_group;
		[PIDTYPE_SID] = INIT_PID_LINK(PIDTYPE_SID), \
		}, \
		.thread_group = LIST_HEAD_INIT(tsk.thread_group), \
		.thread_node = LIST_HEAD_INIT(init_signals.thread_head), \
		INIT_IDS \
		INIT_PERF_EVENTS(tsk) \
		INIT_TRACE_IRQFLAGS \

include/linux/sched.h

+12 −0

Original line number	Diff line number	Diff line
		@@ -551,6 +551,7 @@ struct signal_struct {
		atomic_t sigcnt;
		atomic_t live;
		int nr_threads;
		struct list_head thread_head;

		wait_queue_head_t wait_chldexit; /* for wait4() */

		@@ -1277,6 +1278,7 @@ struct task_struct {
		/* PID/PID hash table linkage. */
		struct pid_link pids[PIDTYPE_MAX];
		struct list_head thread_group;
		struct list_head thread_node;

		struct completion vfork_done; / for vfork() */
		int __user set_child_tid; / CLONE_CHILD_SETTID */
		@@ -2350,6 +2352,16 @@ extern bool current_is_single_threaded(void);
		#define while_each_thread(g, t) \
		while ((t = next_thread(t)) != g)

		#define __for_each_thread(signal, t) \
		list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)

		#define for_each_thread(p, t) \
		__for_each_thread((p)->signal, t)

		/* Careful: this is a double loop, 'break' won't work as expected. */
		#define for_each_process_thread(p, t) \
		for_each_process(p) for_each_thread(p, t)

		static inline int get_nr_threads(struct task_struct *tsk)
		{
		return tsk->signal->nr_threads;

kernel/exit.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -74,6 +74,7 @@ static void __unhash_process(struct task_struct *p, bool group_dead)
		__this_cpu_dec(process_counts);
		}
		list_del_rcu(&p->thread_group);
		list_del_rcu(&p->thread_node);
		}

		/*

kernel/fork.c

+14 −8

Original line number	Diff line number	Diff line
		@@ -1061,6 +1061,11 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
		sig->nr_threads = 1;
		atomic_set(&sig->live, 1);
		atomic_set(&sig->sigcnt, 1);

		/* list_add(thread_node, thread_head) without INIT_LIST_HEAD() */
		sig->thread_head = (struct list_head)LIST_HEAD_INIT(tsk->thread_node);
		tsk->thread_node = (struct list_head)LIST_HEAD_INIT(sig->thread_head);

		init_waitqueue_head(&sig->wait_chldexit);
		sig->curr_target = tsk;
		init_sigpending(&sig->shared_pending);
		@@ -1464,14 +1469,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
		goto bad_fork_free_pid;
		}

		if (clone_flags & CLONE_THREAD) {
		current->signal->nr_threads++;
		atomic_inc(&current->signal->live);
		atomic_inc(&current->signal->sigcnt);
		p->group_leader = current->group_leader;
		list_add_tail_rcu(&p->thread_group, &p->group_leader->thread_group);
		}

		if (likely(p->pid)) {
		ptrace_init_task(p, (clone_flags & CLONE_PTRACE) \|\| trace);

		@@ -1488,6 +1485,15 @@ static struct task_struct *copy_process(unsigned long clone_flags,
		list_add_tail(&p->sibling, &p->real_parent->children);
		list_add_tail_rcu(&p->tasks, &init_task.tasks);
		__this_cpu_inc(process_counts);
		} else {
		current->signal->nr_threads++;
		atomic_inc(&current->signal->live);
		atomic_inc(&current->signal->sigcnt);
		p->group_leader = current->group_leader;
		list_add_tail_rcu(&p->thread_group,
		&p->group_leader->thread_group);
		list_add_tail_rcu(&p->thread_node,
		&p->signal->thread_head);
		}
		attach_pid(p, PIDTYPE_PID, pid);
		nr_threads++;