Jetpack/kernel/kernel-4.9/rt-patches/0005-futex-Cleanup-variable...

124 lines
4.3 KiB
Diff

From 4106b909825da8196544392b3e6cbb00f3e0a5b1 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz@infradead.org>
Date: Wed, 22 Mar 2017 11:35:48 +0100
Subject: [PATCH 005/352] futex: Cleanup variable names for futex_top_waiter()
Upstream commit 499f5aca2cdd5e958b27e2655e7e7f82524f46b1
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>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: xlpang@redhat.com
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: dvhart@infradead.org
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/20170322104151.554710645@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
kernel/futex.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)
diff --git a/kernel/futex.c b/kernel/futex.c
index 053d7be..7f058e1 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1121,14 +1121,14 @@ static int attach_to_pi_owner(u32 uval, union futex_key *key,
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
@@ -1175,7 +1175,7 @@ static int futex_lock_pi_atomic(u32 __user *uaddr, struct futex_hash_bucket *hb,
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;
/*
@@ -1201,9 +1201,9 @@ static int futex_lock_pi_atomic(u32 __user *uaddr, struct futex_hash_bucket *hb,
* 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
@@ -1293,11 +1293,11 @@ static void mark_wake_futex(struct wake_q_head *wake_q, struct futex_q *q)
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;
WAKE_Q(wake_q);
bool deboost;
@@ -1318,11 +1318,11 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
/*
* 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
@@ -2682,7 +2682,7 @@ static int futex_unlock_pi(u32 __user *uaddr, unsigned int flags)
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:
@@ -2706,9 +2706,9 @@ static int futex_unlock_pi(u32 __user *uaddr, unsigned int flags)
* 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.
--
2.7.4