lkml.org 
[lkml]   [2020]   [May]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/4] futex: Remove needless goto's
Date
As stated in the coding style documentation[1], "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 with the
result of the operation when is logically possible to determine it by
the control flow.

[1] https://www.kernel.org/doc/html/latest/process/coding-style.html#centralized-exiting-of-functions

Signed-off-by: André Almeida <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 1f0287a51dce..ec07de620d1e 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1604,13 +1604,13 @@ 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);

@@ -1633,7 +1633,6 @@ 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;
}

@@ -1700,10 +1699,10 @@ 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);
@@ -1721,13 +1720,13 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,
* 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)) {
@@ -1770,7 +1769,6 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,
out_unlock:
double_unlock_hb(hb1, hb2);
wake_up_q(&wake_q);
-out:
return ret;
}

@@ -1977,20 +1975,18 @@ 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);
@@ -2010,7 +2006,7 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,

ret = get_user(curval, uaddr1);
if (ret)
- goto out;
+ return ret;

if (!(flags & FLAGS_SHARED))
goto retry_private;
@@ -2076,7 +2072,7 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
ret = fault_in_user_writeable(uaddr2);
if (!ret)
goto retry;
- goto out;
+ return ret;
case -EBUSY:
case -EAGAIN:
/*
@@ -2195,8 +2191,6 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
double_unlock_hb(hb1, hb2);
wake_up_q(&wake_q);
hb_waiters_dec(hb2);
-
-out:
return ret ? ret : task_count;
}

@@ -2542,7 +2536,7 @@ 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;
}

/*
@@ -2555,7 +2549,7 @@ 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;
}

/*
@@ -2569,8 +2563,7 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
q->pi_state->owner);
}

-out:
- return ret ? ret : locked;
+ return ret;
}

/**
@@ -2667,7 +2660,7 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,

ret = get_user(uval, uaddr);
if (ret)
- goto out;
+ return ret;

if (!(flags & FLAGS_SHARED))
goto retry_private;
@@ -2680,7 +2673,6 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,
ret = -EWOULDBLOCK;
}

-out:
return ret;
}

--
2.26.2
\
 
 \ /
  Last update: 2020-05-27 17:48    [W:0.034 / U:2.556 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site