Commit 8cd9c249 authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Linus Torvalds
Browse files

coredump: simplify core_state->nr_threads calculation 



Change zap_process() to return int instead of incrementing
mm->core_state->nr_threads directly.  Change zap_threads() to set
mm->core_state only on success.

This patch restores the original size of .text, and more importantly now
->nr_threads is used in two places only.

Signed-off-by: default avatarOleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 999d9fc1

fs/exec.c

+16 −17
Original line number Diff line number Diff line
@@ -1502,9 +1502,10 @@ out: 
	return ispipe;

}



static void zap_process(struct task_struct *start)

static int zap_process(struct task_struct *start)

{

	struct task_struct *t;

	int nr = 0;



	start->signal->flags = SIGNAL_GROUP_EXIT;

	start->signal->group_stop_count = 0;
@@ -1512,31 +1513,33 @@ static void zap_process(struct task_struct *start) 
	t = start;

	do {

		if (t != current && t->mm) {

			t->mm->core_state->nr_threads++;

			sigaddset(&t->pending.signal, SIGKILL);

			signal_wake_up(t, 1);

			nr++;

		}

	} while_each_thread(start, t);



	return nr;

}



static inline int zap_threads(struct task_struct *tsk, struct mm_struct *mm,

				int exit_code)

				struct core_state *core_state, int exit_code)

{

	struct task_struct *g, *p;

	unsigned long flags;

	int err = -EAGAIN;

	int nr = -EAGAIN;



	spin_lock_irq(&tsk->sighand->siglock);

	if (!signal_group_exit(tsk->signal)) {

		mm->core_state = core_state;

		tsk->signal->group_exit_code = exit_code;

		zap_process(tsk);

		err = 0;

		nr = zap_process(tsk);

	}

	spin_unlock_irq(&tsk->sighand->siglock);

	if (err)

		return err;

	if (unlikely(nr < 0))

		return nr;



	if (atomic_read(&mm->mm_users) == mm->core_state->nr_threads + 1)

	if (atomic_read(&mm->mm_users) == nr + 1)

		goto done;

	/*

	 * We should find and kill all tasks which use this mm, and we should
@@ -1579,7 +1582,7 @@ static inline int zap_threads(struct task_struct *tsk, struct mm_struct *mm, 
			if (p->mm) {

				if (unlikely(p->mm == mm)) {

					lock_task_sighand(p, &flags);

					zap_process(p);

					nr += zap_process(p);

					unlock_task_sighand(p, &flags);

				}

				break;
@@ -1588,7 +1591,8 @@ static inline int zap_threads(struct task_struct *tsk, struct mm_struct *mm, 
	}

	rcu_read_unlock();

done:

	return mm->core_state->nr_threads;

	core_state->nr_threads = nr;

	return nr;

}



static int coredump_wait(int exit_code)
@@ -1601,12 +1605,7 @@ static int coredump_wait(int exit_code) 


	init_completion(&mm->core_done);

	init_completion(&core_state.startup);

	core_state.nr_threads = 0;

	mm->core_state = &core_state;



	core_waiters = zap_threads(tsk, mm, exit_code);

	if (core_waiters < 0)

		mm->core_state = NULL;

	core_waiters = zap_threads(tsk, mm, &core_state, exit_code);

	up_write(&mm->mmap_sem);



	if (unlikely(core_waiters < 0))

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