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    Subject[PATCH -v5 03/14] futex: Cleanup variable names for futex_top_waiter()
    futex_top_waiter() returns the top-waiter on the pi_mutex. Assinging
    this to a variable 'match' totally obscures the code.

    Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
    ---
    kernel/futex.c | 30 +++++++++++++++---------------
    1 file changed, 15 insertions(+), 15 deletions(-)

    --- a/kernel/futex.c
    +++ b/kernel/futex.c
    @@ -1120,14 +1120,14 @@ static int attach_to_pi_owner(u32 uval,
    static int lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
    union futex_key *key, struct futex_pi_state **ps)
    {
    - struct futex_q *match = futex_top_waiter(hb, key);
    + struct futex_q *top_waiter = futex_top_waiter(hb, key);

    /*
    * If there is a waiter on that futex, validate it and
    * attach to the pi_state when the validation succeeds.
    */
    - if (match)
    - return attach_to_pi_state(uval, match->pi_state, ps);
    + if (top_waiter)
    + return attach_to_pi_state(uval, top_waiter->pi_state, ps);

    /*
    * We are the first waiter - try to look up the owner based on
    @@ -1174,7 +1174,7 @@ static int futex_lock_pi_atomic(u32 __us
    struct task_struct *task, int set_waiters)
    {
    u32 uval, newval, vpid = task_pid_vnr(task);
    - struct futex_q *match;
    + struct futex_q *top_waiter;
    int ret;

    /*
    @@ -1200,9 +1200,9 @@ static int futex_lock_pi_atomic(u32 __us
    * Lookup existing state first. If it exists, try to attach to
    * its pi_state.
    */
    - match = futex_top_waiter(hb, key);
    - if (match)
    - return attach_to_pi_state(uval, match->pi_state, ps);
    + top_waiter = futex_top_waiter(hb, key);
    + if (top_waiter)
    + return attach_to_pi_state(uval, top_waiter->pi_state, ps);

    /*
    * No waiter and user TID is 0. We are here because the
    @@ -1292,11 +1292,11 @@ static void mark_wake_futex(struct wake_
    q->lock_ptr = NULL;
    }

    -static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
    +static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *top_waiter,
    struct futex_hash_bucket *hb)
    {
    struct task_struct *new_owner;
    - struct futex_pi_state *pi_state = this->pi_state;
    + struct futex_pi_state *pi_state = top_waiter->pi_state;
    u32 uninitialized_var(curval), newval;
    DEFINE_WAKE_Q(wake_q);
    bool deboost;
    @@ -1317,11 +1317,11 @@ static int wake_futex_pi(u32 __user *uad

    /*
    * It is possible that the next waiter (the one that brought
    - * this owner to the kernel) timed out and is no longer
    + * top_waiter owner to the kernel) timed out and is no longer
    * waiting on the lock.
    */
    if (!new_owner)
    - new_owner = this->task;
    + new_owner = top_waiter->task;

    /*
    * We pass it to the next owner. The WAITERS bit is always
    @@ -2631,7 +2631,7 @@ static int futex_unlock_pi(u32 __user *u
    u32 uninitialized_var(curval), uval, vpid = task_pid_vnr(current);
    union futex_key key = FUTEX_KEY_INIT;
    struct futex_hash_bucket *hb;
    - struct futex_q *match;
    + struct futex_q *top_waiter;
    int ret;

    retry:
    @@ -2655,9 +2655,9 @@ static int futex_unlock_pi(u32 __user *u
    * all and we at least want to know if user space fiddled
    * with the futex value instead of blindly unlocking.
    */
    - match = futex_top_waiter(hb, &key);
    - if (match) {
    - ret = wake_futex_pi(uaddr, uval, match, hb);
    + top_waiter = futex_top_waiter(hb, &key);
    + if (top_waiter) {
    + ret = wake_futex_pi(uaddr, uval, top_waiter, hb);
    /*
    * In case of success wake_futex_pi dropped the hash
    * bucket lock.

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