job control: introduce JOBCTL_PENDING_MASK and task_clear_jobctl_pending()

This patch introduces JOBCTL_PENDING_MASK and replaces
task_clear_jobctl_stop_pending() with task_clear_jobctl_pending()
which takes an extra @mask argument.

JOBCTL_PENDING_MASK is currently equal to JOBCTL_STOP_PENDING but
future patches will add more bits.  recalc_sigpending_tsk() is updated
to use JOBCTL_PENDING_MASK instead.

task_clear_jobctl_pending() takes @mask which in subset of
JOBCTL_PENDING_MASK and clears the relevant jobctl bits.  If
JOBCTL_STOP_PENDING is set, other STOP bits are cleared together.  All
task_clear_jobctl_stop_pending() users are updated to call
task_clear_jobctl_pending() with JOBCTL_STOP_PENDING which is
functionally identical to task_clear_jobctl_stop_pending().

This patch doesn't cause any functional change.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
This commit is contained in:
Tejun Heo 2011-06-02 11:14:00 +02:00 committed by Oleg Nesterov
parent 81be24b8cd
commit 3759a0d94c
3 changed files with 22 additions and 12 deletions

View file

@ -1772,7 +1772,7 @@ static int zap_process(struct task_struct *start, int exit_code)
t = start;
do {
task_clear_jobctl_stop_pending(t);
task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING);
if (t != current && t->mm) {
sigaddset(&t->pending.signal, SIGKILL);
signal_wake_up(t, 1);

View file

@ -1817,7 +1817,10 @@ extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *
#define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT)
#define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT)
extern void task_clear_jobctl_stop_pending(struct task_struct *task);
#define JOBCTL_PENDING_MASK JOBCTL_STOP_PENDING
extern void task_clear_jobctl_pending(struct task_struct *task,
unsigned int mask);
#ifdef CONFIG_PREEMPT_RCU

View file

@ -124,7 +124,7 @@ static inline int has_pending_signals(sigset_t *signal, sigset_t *blocked)
static int recalc_sigpending_tsk(struct task_struct *t)
{
if ((t->jobctl & JOBCTL_STOP_PENDING) ||
if ((t->jobctl & JOBCTL_PENDING_MASK) ||
PENDING(&t->pending, &t->blocked) ||
PENDING(&t->signal->shared_pending, &t->blocked)) {
set_tsk_thread_flag(t, TIF_SIGPENDING);
@ -245,18 +245,25 @@ static void task_clear_jobctl_trapping(struct task_struct *task)
}
/**
* task_clear_jobctl_stop_pending - clear pending group stop
* task_clear_jobctl_pending - clear jobctl pending bits
* @task: target task
* @mask: pending bits to clear
*
* Clear group stop states for @task.
* Clear @mask from @task->jobctl. @mask must be subset of
* %JOBCTL_PENDING_MASK. If %JOBCTL_STOP_PENDING is being cleared, other
* STOP bits are cleared together.
*
* CONTEXT:
* Must be called with @task->sighand->siglock held.
*/
void task_clear_jobctl_stop_pending(struct task_struct *task)
void task_clear_jobctl_pending(struct task_struct *task, unsigned int mask)
{
task->jobctl &= ~(JOBCTL_STOP_PENDING | JOBCTL_STOP_CONSUME |
JOBCTL_STOP_DEQUEUED);
BUG_ON(mask & ~JOBCTL_PENDING_MASK);
if (mask & JOBCTL_STOP_PENDING)
mask |= JOBCTL_STOP_CONSUME | JOBCTL_STOP_DEQUEUED;
task->jobctl &= ~mask;
}
/**
@ -282,7 +289,7 @@ static bool task_participate_group_stop(struct task_struct *task)
WARN_ON_ONCE(!(task->jobctl & JOBCTL_STOP_PENDING));
task_clear_jobctl_stop_pending(task);
task_clear_jobctl_pending(task, JOBCTL_STOP_PENDING);
if (!consume)
return false;
@ -810,7 +817,7 @@ static int prepare_signal(int sig, struct task_struct *p, int from_ancestor_ns)
rm_from_queue(SIG_KERNEL_STOP_MASK, &signal->shared_pending);
t = p;
do {
task_clear_jobctl_stop_pending(t);
task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING);
rm_from_queue(SIG_KERNEL_STOP_MASK, &t->pending);
wake_up_state(t, __TASK_STOPPED);
} while_each_thread(p, t);
@ -926,7 +933,7 @@ static void complete_signal(int sig, struct task_struct *p, int group)
signal->group_stop_count = 0;
t = p;
do {
task_clear_jobctl_stop_pending(t);
task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING);
sigaddset(&t->pending.signal, SIGKILL);
signal_wake_up(t, 1);
} while_each_thread(p, t);
@ -1161,7 +1168,7 @@ int zap_other_threads(struct task_struct *p)
p->signal->group_stop_count = 0;
while_each_thread(p, t) {
task_clear_jobctl_stop_pending(t);
task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING);
count++;
/* Don't bother with already dead threads */