job control: rename signal->group_stop and flags to jobctl and update them

signal->group_stop currently hosts mostly group stop related flags;
however, it's gonna be used for wider purposes and the GROUP_STOP_
flag prefix becomes confusing.  Rename signal->group_stop to
signal->jobctl and rename all GROUP_STOP_* flags to JOBCTL_*.

Bit position macros JOBCTL_*_BIT are defined and JOBCTL_* flags are
defined in terms of them to allow using bitops later.

While at it, reassign JOBCTL_TRAPPING to bit 22 to better accomodate
future additions.

This doesn't cause any functional change.

-v2: JOBCTL_*_BIT macros added as suggested by Linus.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 4f689cb739a3..134f34cb142b 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -77,13 +77,13 @@ void __ptrace_unlink(struct task_struct *child)
         spin_lock(&child->sighand->siglock);
 
         /*
-         * Reinstate GROUP_STOP_PENDING if group stop is in effect and
+         * Reinstate JOBCTL_STOP_PENDING if group stop is in effect and
          * @child isn't dead.
          */
         if (!(child->flags & PF_EXITING) &&
             (child->signal->flags & SIGNAL_STOP_STOPPED ||
              child->signal->group_stop_count))
-                child->group_stop |= GROUP_STOP_PENDING;
+                child->jobctl |= JOBCTL_STOP_PENDING;
 
         /*
          * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick
@@ -91,7 +91,7 @@ void __ptrace_unlink(struct task_struct *child)
          * is in TASK_TRACED; otherwise, we might unduly disrupt
          * TASK_KILLABLE sleeps.
          */
-        if (child->group_stop & GROUP_STOP_PENDING || task_is_traced(child))
+        if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child))
                 signal_wake_up(child, task_is_traced(child));
 
         spin_unlock(&child->sighand->siglock);
@@ -226,7 +226,7 @@ static int ptrace_attach(struct task_struct *task)
         spin_lock(&task->sighand->siglock);
 
         /*
-         * If the task is already STOPPED, set GROUP_STOP_PENDING and
+         * If the task is already STOPPED, set JOBCTL_STOP_PENDING and
          * TRAPPING, and kick it so that it transits to TRACED.  TRAPPING
          * will be cleared if the child completes the transition or any
          * event which clears the group stop states happens.  We'll wait
@@ -243,7 +243,7 @@ static int ptrace_attach(struct task_struct *task)
          * in and out of STOPPED are protected by siglock.
          */
         if (task_is_stopped(task)) {
-                task->group_stop |= GROUP_STOP_PENDING | GROUP_STOP_TRAPPING;
+                task->jobctl |= JOBCTL_STOP_PENDING | JOBCTL_TRAPPING;
                 signal_wake_up(task, 1);
         }
 
@@ -257,7 +257,7 @@ unlock_creds:
 out:
         if (!retval)
                 wait_event(current->signal->wait_chldexit,
-                           !(task->group_stop & GROUP_STOP_TRAPPING));
+                           !(task->jobctl & JOBCTL_TRAPPING));
         return retval;
 }