linux-kernel - [tip: locking/core] futex: Remove needless goto's

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Message-ID: <159502328082.4006.1363384803815710771.tip-bot2@tip-bot2>
Date:   Fri, 17 Jul 2020 22:01:20 -0000
From:   tip-bot2 for André Almeida 
        <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     andrealmeid@...labora.com, Thomas Gleixner <tglx@...utronix.de>,
        x86 <x86@...nel.org>, LKML <linux-kernel@...r.kernel.org>
Subject: [tip: locking/core] futex: Remove needless goto's

The following commit has been merged into the locking/core branch of tip:

Commit-ID:     d7c5ed73b19c4640426d9c106f70ec2cb532034d
Gitweb:        https://git.kernel.org/tip/d7c5ed73b19c4640426d9c106f70ec2cb532034d
Author:        André Almeida <andrealmeid@...labora.com>
AuthorDate:    Thu, 02 Jul 2020 17:28:41 -03:00
Committer:     Thomas Gleixner <tglx@...utronix.de>
CommitterDate: Fri, 17 Jul 2020 23:58:49 +02:00

futex: Remove needless goto's

As stated in the coding style documentation, "if there is no cleanup
needed then just return directly", instead of jumping to a label and
then returning.

Remove such goto's and replace with a return statement.  When there's a
ternary operator on the return value, replace it with the result of the
operation when it is logically possible to determine it by the control
flow.

Signed-off-by: André Almeida <andrealmeid@...labora.com>
Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
Link: https://lkml.kernel.org/r/20200702202843.520764-3-andrealmeid@collabora.com

---
 kernel/futex.c | 40 ++++++++++++++++------------------------
 1 file changed, 16 insertions(+), 24 deletions(-)

diff --git a/kernel/futex.c b/kernel/futex.c
index bd9adfc..362fbca 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1607,13 +1607,13 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset)
 
 	ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key, FUTEX_READ);
 	if (unlikely(ret != 0))
-		goto out;
+		return ret;
 
 	hb = hash_futex(&key);
 
 	/* Make sure we really have tasks to wakeup */
 	if (!hb_waiters_pending(hb))
-		goto out;
+		return ret;
 
 	spin_lock(&hb->lock);
 
@@ -1636,7 +1636,6 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset)
 
 	spin_unlock(&hb->lock);
 	wake_up_q(&wake_q);
-out:
 	return ret;
 }
 
@@ -1703,10 +1702,10 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,
 retry:
 	ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, FUTEX_READ);
 	if (unlikely(ret != 0))
-		goto out;
+		return ret;
 	ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, FUTEX_WRITE);
 	if (unlikely(ret != 0))
-		goto out;
+		return ret;
 
 	hb1 = hash_futex(&key1);
 	hb2 = hash_futex(&key2);
@@ -1724,13 +1723,13 @@ retry_private:
 			 * an MMU, but we might get them from range checking
 			 */
 			ret = op_ret;
-			goto out;
+			return ret;
 		}
 
 		if (op_ret == -EFAULT) {
 			ret = fault_in_user_writeable(uaddr2);
 			if (ret)
-				goto out;
+				return ret;
 		}
 
 		if (!(flags & FLAGS_SHARED)) {
@@ -1773,7 +1772,6 @@ retry_private:
 out_unlock:
 	double_unlock_hb(hb1, hb2);
 	wake_up_q(&wake_q);
-out:
 	return ret;
 }
 
@@ -1980,20 +1978,18 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
 retry:
 	ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, FUTEX_READ);
 	if (unlikely(ret != 0))
-		goto out;
+		return ret;
 	ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2,
 			    requeue_pi ? FUTEX_WRITE : FUTEX_READ);
 	if (unlikely(ret != 0))
-		goto out;
+		return ret;
 
 	/*
 	 * The check above which compares uaddrs is not sufficient for
 	 * shared futexes. We need to compare the keys:
 	 */
-	if (requeue_pi && match_futex(&key1, &key2)) {
-		ret = -EINVAL;
-		goto out;
-	}
+	if (requeue_pi && match_futex(&key1, &key2))
+		return -EINVAL;
 
 	hb1 = hash_futex(&key1);
 	hb2 = hash_futex(&key2);
@@ -2013,7 +2009,7 @@ retry_private:
 
 			ret = get_user(curval, uaddr1);
 			if (ret)
-				goto out;
+				return ret;
 
 			if (!(flags & FLAGS_SHARED))
 				goto retry_private;
@@ -2079,7 +2075,7 @@ retry_private:
 			ret = fault_in_user_writeable(uaddr2);
 			if (!ret)
 				goto retry;
-			goto out;
+			return ret;
 		case -EBUSY:
 		case -EAGAIN:
 			/*
@@ -2198,8 +2194,6 @@ out_unlock:
 	double_unlock_hb(hb1, hb2);
 	wake_up_q(&wake_q);
 	hb_waiters_dec(hb2);
-
-out:
 	return ret ? ret : task_count;
 }
 
@@ -2545,7 +2539,7 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
 		 */
 		if (q->pi_state->owner != current)
 			ret = fixup_pi_state_owner(uaddr, q, current);
-		goto out;
+		return ret ? ret : locked;
 	}
 
 	/*
@@ -2558,7 +2552,7 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
 	 */
 	if (q->pi_state->owner == current) {
 		ret = fixup_pi_state_owner(uaddr, q, NULL);
-		goto out;
+		return ret;
 	}
 
 	/*
@@ -2572,8 +2566,7 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
 				q->pi_state->owner);
 	}
 
-out:
-	return ret ? ret : locked;
+	return ret;
 }
 
 /**
@@ -2670,7 +2663,7 @@ retry_private:
 
 		ret = get_user(uval, uaddr);
 		if (ret)
-			goto out;
+			return ret;
 
 		if (!(flags & FLAGS_SHARED))
 			goto retry_private;
@@ -2683,7 +2676,6 @@ retry_private:
 		ret = -EWOULDBLOCK;
 	}
 
-out:
 	return ret;
 }