From 6301cb95c119ebf324bb96ee226fa9ddffad80a7 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 17 Jul 2009 14:15:47 +0200 Subject: sched: fix nr_uninterruptible accounting of frozen tasks really commit e3c8ca8336 (sched: do not count frozen tasks toward load) broke the nr_uninterruptible accounting on freeze/thaw. On freeze the task is excluded from accounting with a check for (task->flags & PF_FROZEN), but that flag is cleared before the task is thawed. So while we prevent that the task with state TASK_UNINTERRUPTIBLE is accounted to nr_uninterruptible on freeze we decrement nr_uninterruptible on thaw. Use a separate flag which is handled by the freezing task itself. Set it before calling the scheduler with TASK_UNINTERRUPTIBLE state and clear it after we return from frozen state. Cc: Signed-off-by: Thomas Gleixner --- kernel/freezer.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'kernel/freezer.c') diff --git a/kernel/freezer.c b/kernel/freezer.c index 2f4936cf7083..bd1d42b17cb2 100644 --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -44,12 +44,19 @@ void refrigerator(void) recalc_sigpending(); /* We sent fake signal, clean it up */ spin_unlock_irq(¤t->sighand->siglock); + /* prevent accounting of that task to load */ + current->flags |= PF_FREEZING; + for (;;) { set_current_state(TASK_UNINTERRUPTIBLE); if (!frozen(current)) break; schedule(); } + + /* Remove the accounting blocker */ + current->flags &= ~PF_FREEZING; + pr_debug("%s left refrigerator\n", current->comm); __set_current_state(save); } -- cgit