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futex: Avoid redudant evaluation of task_pid_vnr()

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The result is not going to change under us, so no need to reevaluate
this over and over. Seems to be a leftover from the mechanical mass
conversion of task->pid to task_pid_vnr(tsk).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Thomas Gleixner
2011-03-11 11:51:22 +01:00
parent 8fe8f545c6
commit c0c9ed1504
1 changed files with 8 additions and 8 deletions
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16
kernel/futex.c
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@@ -674,7 +674,7 @@ static int futex_lock_pi_atomic(u32 __user *uaddr, struct futex_hash_bucket *hb,
struct task_struct *task, int set_waiters) struct task_struct *task, int set_waiters)
{ {
int lock_taken, ret, ownerdied = 0; int lock_taken, ret, ownerdied = 0;
u32 uval, newval, curval; u32 uval, newval, curval, vpid = task_pid_vnr(task);
retry: retry:
ret = lock_taken = 0; ret = lock_taken = 0;
@@ -684,7 +684,7 @@ retry:
* (by doing a 0 -> TID atomic cmpxchg), while holding all * (by doing a 0 -> TID atomic cmpxchg), while holding all
* the locks. It will most likely not succeed. * the locks. It will most likely not succeed.
*/ */
newval = task_pid_vnr(task); newval = vpid;
if (set_waiters) if (set_waiters)
newval |= FUTEX_WAITERS; newval |= FUTEX_WAITERS;
@@ -696,7 +696,7 @@ retry:
/* /*
* Detect deadlocks. * Detect deadlocks.
*/ */
if ((unlikely((curval & FUTEX_TID_MASK) == task_pid_vnr(task)))) if ((unlikely((curval & FUTEX_TID_MASK) == vpid)))
return -EDEADLK; return -EDEADLK;
/* /*
@@ -723,7 +723,7 @@ retry:
*/ */
if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) { if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) {
/* Keep the OWNER_DIED bit */ /* Keep the OWNER_DIED bit */
newval = (curval & ~FUTEX_TID_MASK) | task_pid_vnr(task); newval = (curval & ~FUTEX_TID_MASK) | vpid;
ownerdied = 0; ownerdied = 0;
lock_taken = 1; lock_taken = 1;
} }
@@ -2047,9 +2047,9 @@ static int futex_unlock_pi(u32 __user *uaddr, unsigned int flags)
{ {
struct futex_hash_bucket *hb; struct futex_hash_bucket *hb;
struct futex_q *this, *next; struct futex_q *this, *next;
u32 uval;
struct plist_head *head; struct plist_head *head;
union futex_key key = FUTEX_KEY_INIT; union futex_key key = FUTEX_KEY_INIT;
u32 uval, vpid = task_pid_vnr(current);
int ret; int ret;
retry: retry:
@@ -2058,7 +2058,7 @@ retry:
/* /*
* We release only a lock we actually own: * We release only a lock we actually own:
*/ */
if ((uval & FUTEX_TID_MASK) != task_pid_vnr(current)) if ((uval & FUTEX_TID_MASK) != vpid)
return -EPERM; return -EPERM;
ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key); ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key);
@@ -2074,7 +2074,7 @@ retry:
* anyone else up: * anyone else up:
*/ */
if (!(uval & FUTEX_OWNER_DIED)) if (!(uval & FUTEX_OWNER_DIED))
uval = cmpxchg_futex_value_locked(uaddr, task_pid_vnr(current), 0); uval = cmpxchg_futex_value_locked(uaddr, vpid, 0);
if (unlikely(uval == -EFAULT)) if (unlikely(uval == -EFAULT))
@@ -2083,7 +2083,7 @@ retry:
* Rare case: we managed to release the lock atomically, * Rare case: we managed to release the lock atomically,
* no need to wake anyone else up: * no need to wake anyone else up:
*/ */
if (unlikely(uval == task_pid_vnr(current))) if (unlikely(uval == vpid))
goto out_unlock; goto out_unlock;
/* /*