futexes: Clean up various details

- Remove unnecessary head variables.
- Delete unused parameter in queue_unlock().

Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jason Low <jason.low2@hp.com>
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Scott Norton <scott.norton@hp.com>
Cc: Tom Vaden <tom.vaden@hp.com>
Cc: Aswin Chandramouleeswaran <aswin@hp.com>
Cc: Waiman Long <Waiman.Long@hp.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1389569486-25487-2-git-send-email-davidlohr@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 12 insertions, 27 deletions

diff --git a/kernel/futex.c b/kernel/futex.c
index f6ff0191ecf7..085f5fa0b342 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -598,13 +598,10 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
 {
         struct futex_pi_state *pi_state = NULL;
         struct futex_q *this, *next;
-        struct plist_head *head;
         struct task_struct *p;
         pid_t pid = uval & FUTEX_TID_MASK;
 
-        head = &hb->chain;
-
-        plist_for_each_entry_safe(this, next, head, list) {
+        plist_for_each_entry_safe(this, next, &hb->chain, list) {
                 if (match_futex(&this->key, key)) {
                         /*
                          * Another waiter already exists - bump up
@@ -986,7 +983,6 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset)
 {
         struct futex_hash_bucket *hb;
         struct futex_q *this, *next;
-        struct plist_head *head;
         union futex_key key = FUTEX_KEY_INIT;
         int ret;
 
@@ -999,9 +995,8 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset)
 
         hb = hash_futex(&key);
         spin_lock(&hb->lock);
-        head = &hb->chain;
 
-        plist_for_each_entry_safe(this, next, head, list) {
+        plist_for_each_entry_safe(this, next, &hb->chain, list) {
                 if (match_futex (&this->key, &key)) {
                         if (this->pi_state || this->rt_waiter) {
                                 ret = -EINVAL;
@@ -1034,7 +1029,6 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,
 {
         union futex_key key1 = FUTEX_KEY_INIT, key2 = FUTEX_KEY_INIT;
         struct futex_hash_bucket *hb1, *hb2;
-        struct plist_head *head;
         struct futex_q *this, *next;
         int ret, op_ret;
 
@@ -1082,9 +1076,7 @@ retry_private:
                 goto retry;
         }
 
-        head = &hb1->chain;
-
-        plist_for_each_entry_safe(this, next, head, list) {
+        plist_for_each_entry_safe(this, next, &hb1->chain, list) {
                 if (match_futex (&this->key, &key1)) {
                         if (this->pi_state || this->rt_waiter) {
                                 ret = -EINVAL;
@@ -1097,10 +1089,8 @@ retry_private:
         }
 
         if (op_ret > 0) {
-                head = &hb2->chain;
-
                 op_ret = 0;
-                plist_for_each_entry_safe(this, next, head, list) {
+                plist_for_each_entry_safe(this, next, &hb2->chain, list) {
                         if (match_futex (&this->key, &key2)) {
                                 if (this->pi_state || this->rt_waiter) {
                                         ret = -EINVAL;
@@ -1270,7 +1260,6 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
         int drop_count = 0, task_count = 0, ret;
         struct futex_pi_state *pi_state = NULL;
         struct futex_hash_bucket *hb1, *hb2;
-        struct plist_head *head1;
         struct futex_q *this, *next;
         u32 curval2;
 
@@ -1393,8 +1382,7 @@ retry_private:
                 }
         }
 
-        head1 = &hb1->chain;
-        plist_for_each_entry_safe(this, next, head1, list) {
+        plist_for_each_entry_safe(this, next, &hb1->chain, list) {
                 if (task_count - nr_wake >= nr_requeue)
                         break;
 
@@ -1494,7 +1482,7 @@ static inline struct futex_hash_bucket *queue_lock(struct futex_q *q)
 }
 
 static inline void
-queue_unlock(struct futex_q *q, struct futex_hash_bucket *hb)
+queue_unlock(struct futex_hash_bucket *hb)
         __releases(&hb->lock)
 {
         spin_unlock(&hb->lock);
@@ -1867,7 +1855,7 @@ retry_private:
         ret = get_futex_value_locked(&uval, uaddr);
 
         if (ret) {
-                queue_unlock(q, *hb);
+                queue_unlock(*hb);
 
                 ret = get_user(uval, uaddr);
                 if (ret)
@@ -1881,7 +1869,7 @@ retry_private:
         }
 
         if (uval != val) {
-                queue_unlock(q, *hb);
+                queue_unlock(*hb);
                 ret = -EWOULDBLOCK;
         }
 
@@ -2029,7 +2017,7 @@ retry_private:
                          * Task is exiting and we just wait for the
                          * exit to complete.
                          */
-                        queue_unlock(&q, hb);
+                        queue_unlock(hb);
                         put_futex_key(&q.key);
                         cond_resched();
                         goto retry;
@@ -2081,7 +2069,7 @@ retry_private:
         goto out_put_key;
 
 out_unlock_put_key:
-        queue_unlock(&q, hb);
+        queue_unlock(hb);
 
 out_put_key:
         put_futex_key(&q.key);
@@ -2091,7 +2079,7 @@ out:
         return ret != -EINTR ? ret : -ERESTARTNOINTR;
 
 uaddr_faulted:
-        queue_unlock(&q, hb);
+        queue_unlock(hb);
 
         ret = fault_in_user_writeable(uaddr);
         if (ret)
@@ -2113,7 +2101,6 @@ static int futex_unlock_pi(u32 __user *uaddr, unsigned int flags)
 {
         struct futex_hash_bucket *hb;
         struct futex_q *this, *next;
-        struct plist_head *head;
         union futex_key key = FUTEX_KEY_INIT;
         u32 uval, vpid = task_pid_vnr(current);
         int ret;
@@ -2153,9 +2140,7 @@ retry:
          * Ok, other tasks may need to be woken up - check waiters
          * and do the wakeup if necessary:
          */
-        head = &hb->chain;
-
-        plist_for_each_entry_safe(this, next, head, list) {
+        plist_for_each_entry_safe(this, next, &hb->chain, list) {
                 if (!match_futex (&this->key, &key))
                         continue;
                 ret = wake_futex_pi(uaddr, uval, this);