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sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming

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So I've noticed a number of instances where it was not obvious from the
code whether ->task_list was for a wait-queue head or a wait-queue entry.

Furthermore, there's a number of wait-queue users where the lists are
not for 'tasks' but other entities (poll tables, etc.), in which case
the 'task_list' name is actively confusing.

To clear this all up, name the wait-queue head and entry list structure
fields unambiguously:

	struct wait_queue_head::task_list	=> ::head
	struct wait_queue_entry::task_list	=> ::entry

For example, this code:

	rqw->wait.task_list.next != &wait->task_list

... is was pretty unclear (to me) what it's doing, while now it's written this way:

	rqw->wait.head.next != &wait->entry

... which makes it pretty clear that we are iterating a list until we see the head.

Other examples are:

	list_for_each_entry_safe(pos, next, &x->task_list, task_list) {
	list_for_each_entry(wq, &fence->wait.task_list, task_list) {

... where it's unclear (to me) what we are iterating, and during review it's
hard to tell whether it's trying to walk a wait-queue entry (which would be
a bug), while now it's written as:

	list_for_each_entry_safe(pos, next, &x->head, entry) {
	list_for_each_entry(wq, &fence->wait.head, entry) {

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar 2017-06-20 12:06:46 +02:00
parent 5822a454d6
commit 2055da9738
18 changed files with 66 additions and 68 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
block/blk-mq.c
View File

@ -933,7 +933,7 @@ static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, int fla
hctx = container_of(wait, struct blk_mq_hw_ctx, dispatch_wait);
list_del(&wait->task_list);
list_del(&wait->entry);
clear_bit_unlock(BLK_MQ_S_TAG_WAITING, &hctx->state);
blk_mq_run_hw_queue(hctx, true);
return 1;

2
block/blk-wbt.c
View File

@ -520,7 +520,7 @@ static inline bool may_queue(struct rq_wb *rwb, struct rq_wait *rqw,
* in line to be woken up, wait for our turn.
*/
if (waitqueue_active(&rqw->wait) &&
rqw->wait.task_list.next != &wait->task_list)
rqw->wait.head.next != &wait->entry)
return false;
return atomic_inc_below(&rqw->inflight, get_limit(rwb, rw));

8
block/kyber-iosched.c
View File

@ -385,7 +385,7 @@ static int kyber_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
for (i = 0; i < KYBER_NUM_DOMAINS; i++) {
INIT_LIST_HEAD(&khd->rqs[i]);
INIT_LIST_HEAD(&khd->domain_wait[i].task_list);
INIT_LIST_HEAD(&khd->domain_wait[i].entry);
atomic_set(&khd->wait_index[i], 0);
}
@ -512,7 +512,7 @@ static int kyber_domain_wake(wait_queue_entry_t *wait, unsigned mode, int flags,
{
struct blk_mq_hw_ctx *hctx = READ_ONCE(wait->private);
list_del_init(&wait->task_list);
list_del_init(&wait->entry);
blk_mq_run_hw_queue(hctx, true);
return 1;
}
@ -536,7 +536,7 @@ static int kyber_get_domain_token(struct kyber_queue_data *kqd,
* run when one becomes available. Note that this is serialized on
* khd->lock, but we still need to be careful about the waker.
*/
if (list_empty_careful(&wait->task_list)) {
if (list_empty_careful(&wait->entry)) {
init_waitqueue_func_entry(wait, kyber_domain_wake);
wait->private = hctx;
ws = sbq_wait_ptr(domain_tokens,
@ -736,7 +736,7 @@ static int kyber_##name##_waiting_show(void *data, struct seq_file *m) \
struct kyber_hctx_data *khd = hctx->sched_data; \
wait_queue_entry_t *wait = &khd->domain_wait[domain]; \
\
seq_printf(m, "%d\n", !list_empty_careful(&wait->task_list)); \
seq_printf(m, "%d\n", !list_empty_careful(&wait->entry)); \
return 0; \
}
KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_READ, read)

21
drivers/gpu/drm/i915/i915_sw_fence.c
View File

@ -160,31 +160,30 @@ static void __i915_sw_fence_wake_up_all(struct i915_sw_fence *fence,
/*
* To prevent unbounded recursion as we traverse the graph of
* i915_sw_fences, we move the task_list from this, the next ready
* fence, to the tail of the original fence's task_list
* i915_sw_fences, we move the entry list from this, the next ready
* fence, to the tail of the original fence's entry list
* (and so added to the list to be woken).
*/
spin_lock_irqsave_nested(&x->lock, flags, 1 + !!continuation);
if (continuation) {
list_for_each_entry_safe(pos, next, &x->task_list, task_list) {
list_for_each_entry_safe(pos, next, &x->head, entry) {
if (pos->func == autoremove_wake_function)
pos->func(pos, TASK_NORMAL, 0, continuation);
else
list_move_tail(&pos->task_list, continuation);
list_move_tail(&pos->entry, continuation);
}
} else {
LIST_HEAD(extra);
do {
list_for_each_entry_safe(pos, next,
&x->task_list, task_list)
list_for_each_entry_safe(pos, next, &x->head, entry)
pos->func(pos, TASK_NORMAL, 0, &extra);
if (list_empty(&extra))
break;
list_splice_tail_init(&extra, &x->task_list);
list_splice_tail_init(&extra, &x->head);
} while (1);
}
spin_unlock_irqrestore(&x->lock, flags);
@ -256,7 +255,7 @@ void i915_sw_fence_commit(struct i915_sw_fence *fence)
static int i915_sw_fence_wake(wait_queue_entry_t *wq, unsigned mode, int flags, void *key)
{
list_del(&wq->task_list);
list_del(&wq->entry);
__i915_sw_fence_complete(wq->private, key);
i915_sw_fence_put(wq->private);
if (wq->flags & I915_SW_FENCE_FLAG_ALLOC)
@ -275,7 +274,7 @@ static bool __i915_sw_fence_check_if_after(struct i915_sw_fence *fence,
if (fence == signaler)
return true;
list_for_each_entry(wq, &fence->wait.task_list, task_list) {
list_for_each_entry(wq, &fence->wait.head, entry) {
if (wq->func != i915_sw_fence_wake)
continue;
@ -293,7 +292,7 @@ static void __i915_sw_fence_clear_checked_bit(struct i915_sw_fence *fence)
if (!__test_and_clear_bit(I915_SW_FENCE_CHECKED_BIT, &fence->flags))
return;
list_for_each_entry(wq, &fence->wait.task_list, task_list) {
list_for_each_entry(wq, &fence->wait.head, entry) {
if (wq->func != i915_sw_fence_wake)
continue;
@ -350,7 +349,7 @@ static int __i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
pending |= I915_SW_FENCE_FLAG_ALLOC;
}
INIT_LIST_HEAD(&wq->task_list);
INIT_LIST_HEAD(&wq->entry);
wq->flags = pending;
wq->func = i915_sw_fence_wake;
wq->private = i915_sw_fence_get(fence);

2
drivers/rtc/rtc-imxdi.c
View File

@ -709,7 +709,7 @@ static irqreturn_t dryice_irq(int irq, void *dev_id)
/*If the write wait queue is empty then there is no pending
operations. It means the interrupt is for DryIce -Security.
IRQ must be returned as none.*/
if (list_empty_careful(&imxdi->write_wait.task_list))
if (list_empty_careful(&imxdi->write_wait.head))
return rc;
/* DSR_WCF clears itself on DSR read */

2
fs/cachefiles/rdwr.c
View File

@ -48,7 +48,7 @@ static int cachefiles_read_waiter(wait_queue_entry_t *wait, unsigned mode,
}
/* remove from the waitqueue */
list_del(&wait->task_list);
list_del(&wait->entry);
/* move onto the action list and queue for FS-Cache thread pool */
ASSERT(monitor->op);

2
fs/eventpoll.c
View File

@ -1094,7 +1094,7 @@ static int ep_poll_callback(wait_queue_entry_t *wait, unsigned mode, int sync, v
* can't use __remove_wait_queue(). whead->lock is held by
* the caller.
*/
list_del_init(&wait->task_list);
list_del_init(&wait->entry);
}
spin_lock_irqsave(&ep->lock, flags);

2
fs/fs_pin.c
View File

@ -61,7 +61,7 @@ void pin_kill(struct fs_pin *p)
rcu_read_unlock();
schedule();
rcu_read_lock();
if (likely(list_empty(&wait.task_list)))
if (likely(list_empty(&wait.entry)))
break;
/* OK, we know p couldn't have been freed yet */
spin_lock_irq(&p->wait.lock);

3
fs/nilfs2/segment.c
View File

@ -2206,8 +2206,7 @@ static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err)
unsigned long flags;
spin_lock_irqsave(&sci->sc_wait_request.lock, flags);
list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list,
wq.task_list) {
list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) {
if (!atomic_read(&wrq->done) &&
nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) {
wrq->err = err;

8
fs/orangefs/orangefs-bufmap.c
View File

@ -46,7 +46,7 @@ static void run_down(struct slot_map *m)
spin_lock(&m->q.lock);
if (m->c != -1) {
for (;;) {
if (likely(list_empty(&wait.task_list)))
if (likely(list_empty(&wait.entry)))
__add_wait_queue_entry_tail(&m->q, &wait);
set_current_state(TASK_UNINTERRUPTIBLE);
@ -84,7 +84,7 @@ static int wait_for_free(struct slot_map *m)
do {
long n = left, t;
if (likely(list_empty(&wait.task_list)))
if (likely(list_empty(&wait.entry)))
__add_wait_queue_entry_tail_exclusive(&m->q, &wait);
set_current_state(TASK_INTERRUPTIBLE);
@ -108,8 +108,8 @@ static int wait_for_free(struct slot_map *m)
left = -EINTR;
} while (left > 0);
if (!list_empty(&wait.task_list))
list_del(&wait.task_list);
if (!list_empty(&wait.entry))
list_del(&wait.entry);
else if (left <= 0 && waitqueue_active(&m->q))
__wake_up_locked_key(&m->q, TASK_INTERRUPTIBLE, NULL);
__set_current_state(TASK_RUNNING);

22
fs/userfaultfd.c
View File

@ -129,7 +129,7 @@ static int userfaultfd_wake_function(wait_queue_entry_t *wq, unsigned mode,
* wouldn't be enough, the smp_mb__before_spinlock is
* enough to avoid an explicit smp_mb() here.
*/
list_del_init(&wq->task_list);
list_del_init(&wq->entry);
out:
return ret;
}
@ -522,13 +522,13 @@ int handle_userfault(struct vm_fault *vmf, unsigned long reason)
* and it's fine not to block on the spinlock. The uwq on this
* kernel stack can be released after the list_del_init.
*/
if (!list_empty_careful(&uwq.wq.task_list)) {
if (!list_empty_careful(&uwq.wq.entry)) {
spin_lock(&ctx->fault_pending_wqh.lock);
/*
* No need of list_del_init(), the uwq on the stack
* will be freed shortly anyway.
*/
list_del(&uwq.wq.task_list);
list_del(&uwq.wq.entry);
spin_unlock(&ctx->fault_pending_wqh.lock);
}
@ -869,7 +869,7 @@ static inline struct userfaultfd_wait_queue *find_userfault_in(
if (!waitqueue_active(wqh))
goto out;
/* walk in reverse to provide FIFO behavior to read userfaults */
wq = list_last_entry(&wqh->task_list, typeof(*wq), task_list);
wq = list_last_entry(&wqh->head, typeof(*wq), entry);
uwq = container_of(wq, struct userfaultfd_wait_queue, wq);
out:
return uwq;
@ -1003,14 +1003,14 @@ static ssize_t userfaultfd_ctx_read(struct userfaultfd_ctx *ctx, int no_wait,
* changes __remove_wait_queue() to use
* list_del_init() in turn breaking the
* !list_empty_careful() check in
* handle_userfault(). The uwq->wq.task_list
* handle_userfault(). The uwq->wq.head list
* must never be empty at any time during the
* refile, or the waitqueue could disappear
* from under us. The "wait_queue_head_t"
* parameter of __remove_wait_queue() is unused
* anyway.
*/
list_del(&uwq->wq.task_list);
list_del(&uwq->wq.entry);
__add_wait_queue(&ctx->fault_wqh, &uwq->wq);
write_seqcount_end(&ctx->refile_seq);
@ -1032,7 +1032,7 @@ static ssize_t userfaultfd_ctx_read(struct userfaultfd_ctx *ctx, int no_wait,
fork_nctx = (struct userfaultfd_ctx *)
(unsigned long)
uwq->msg.arg.reserved.reserved1;
list_move(&uwq->wq.task_list, &fork_event);
list_move(&uwq->wq.entry, &fork_event);
spin_unlock(&ctx->event_wqh.lock);
ret = 0;
break;
@ -1069,8 +1069,8 @@ static ssize_t userfaultfd_ctx_read(struct userfaultfd_ctx *ctx, int no_wait,
if (!list_empty(&fork_event)) {
uwq = list_first_entry(&fork_event,
typeof(*uwq),
wq.task_list);
list_del(&uwq->wq.task_list);
wq.entry);
list_del(&uwq->wq.entry);
__add_wait_queue(&ctx->event_wqh, &uwq->wq);
userfaultfd_event_complete(ctx, uwq);
}
@ -1752,12 +1752,12 @@ static void userfaultfd_show_fdinfo(struct seq_file *m, struct file *f)
unsigned long pending = 0, total = 0;
spin_lock(&ctx->fault_pending_wqh.lock);
list_for_each_entry(wq, &ctx->fault_pending_wqh.task_list, task_list) {
list_for_each_entry(wq, &ctx->fault_pending_wqh.head, entry) {
uwq = container_of(wq, struct userfaultfd_wait_queue, wq);
pending++;
total++;
}
list_for_each_entry(wq, &ctx->fault_wqh.task_list, task_list) {
list_for_each_entry(wq, &ctx->fault_wqh.head, entry) {
uwq = container_of(wq, struct userfaultfd_wait_queue, wq);
total++;
}

20
include/linux/wait.h
View File

@ -26,12 +26,12 @@ struct wait_queue_entry {
unsigned int flags;
void *private;
wait_queue_func_t func;
struct list_head task_list;
struct list_head entry;
};
struct wait_queue_head {
spinlock_t lock;
struct list_head task_list;
struct list_head head;
};
typedef struct wait_queue_head wait_queue_head_t;
@ -44,14 +44,14 @@ struct task_struct;
#define __WAITQUEUE_INITIALIZER(name, tsk) { \
.private = tsk, \
.func = default_wake_function, \
.task_list = { NULL, NULL } }
.entry = { NULL, NULL } }
#define DECLARE_WAITQUEUE(name, tsk) \
struct wait_queue_entry name = __WAITQUEUE_INITIALIZER(name, tsk)
#define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \
.lock = __SPIN_LOCK_UNLOCKED(name.lock), \
.task_list = { &(name).task_list, &(name).task_list } }
.head = { &(name).head, &(name).head } }
#define DECLARE_WAIT_QUEUE_HEAD(name) \
struct wait_queue_head name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
@ -121,7 +121,7 @@ init_waitqueue_func_entry(struct wait_queue_entry *wq_entry, wait_queue_func_t f
*/
static inline int waitqueue_active(struct wait_queue_head *wq_head)
{
return !list_empty(&wq_head->task_list);
return !list_empty(&wq_head->head);
}
/**
@ -151,7 +151,7 @@ extern void remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue
static inline void __add_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
{
list_add(&wq_entry->task_list, &wq_head->task_list);
list_add(&wq_entry->entry, &wq_head->head);
}
/*
@ -166,7 +166,7 @@ __add_wait_queue_exclusive(struct wait_queue_head *wq_head, struct wait_queue_en
static inline void __add_wait_queue_entry_tail(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
{
list_add_tail(&wq_entry->task_list, &wq_head->task_list);
list_add_tail(&wq_entry->entry, &wq_head->head);
}
static inline void
@ -179,7 +179,7 @@ __add_wait_queue_entry_tail_exclusive(struct wait_queue_head *wq_head, struct wa
static inline void
__remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
{
list_del(&wq_entry->task_list);
list_del(&wq_entry->entry);
}
void __wake_up(struct wait_queue_head *wq_head, unsigned int mode, int nr, void *key);
@ -952,7 +952,7 @@ int autoremove_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, i
struct wait_queue_entry name = { \
.private = current, \
.func = function, \
.task_list = LIST_HEAD_INIT((name).task_list), \
.entry = LIST_HEAD_INIT((name).entry), \
}
#define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)
@ -961,7 +961,7 @@ int autoremove_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, i
do { \
(wait)->private = current; \
(wait)->func = autoremove_wake_function; \
INIT_LIST_HEAD(&(wait)->task_list); \
INIT_LIST_HEAD(&(wait)->entry); \
(wait)->flags = 0; \
} while (0)

4
include/linux/wait_bit.h
View File

@ -45,8 +45,8 @@ int wake_bit_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync
.wq_entry = { \
.private = current, \
.func = wake_bit_function, \
.task_list = \
LIST_HEAD_INIT((name).wq_entry.task_list), \
.entry = \
LIST_HEAD_INIT((name).wq_entry.entry), \
}, \
}

24
kernel/sched/wait.c
View File

@ -16,7 +16,7 @@ void __init_waitqueue_head(struct wait_queue_head *wq_head, const char *name, st
{
spin_lock_init(&wq_head->lock);
lockdep_set_class_and_name(&wq_head->lock, key, name);
INIT_LIST_HEAD(&wq_head->task_list);
INIT_LIST_HEAD(&wq_head->head);
}
EXPORT_SYMBOL(__init_waitqueue_head);
@ -68,7 +68,7 @@ static void __wake_up_common(struct wait_queue_head *wq_head, unsigned int mode,
{
wait_queue_entry_t *curr, *next;
list_for_each_entry_safe(curr, next, &wq_head->task_list, task_list) {
list_for_each_entry_safe(curr, next, &wq_head->head, entry) {
unsigned flags = curr->flags;
if (curr->func(curr, mode, wake_flags, key) &&
@ -176,7 +176,7 @@ prepare_to_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_ent
wq_entry->flags &= ~WQ_FLAG_EXCLUSIVE;
spin_lock_irqsave(&wq_head->lock, flags);
if (list_empty(&wq_entry->task_list))
if (list_empty(&wq_entry->entry))
__add_wait_queue(wq_head, wq_entry);
set_current_state(state);
spin_unlock_irqrestore(&wq_head->lock, flags);
@ -190,7 +190,7 @@ prepare_to_wait_exclusive(struct wait_queue_head *wq_head, struct wait_queue_ent
wq_entry->flags |= WQ_FLAG_EXCLUSIVE;
spin_lock_irqsave(&wq_head->lock, flags);
if (list_empty(&wq_entry->task_list))
if (list_empty(&wq_entry->entry))
__add_wait_queue_entry_tail(wq_head, wq_entry);
set_current_state(state);
spin_unlock_irqrestore(&wq_head->lock, flags);
@ -202,7 +202,7 @@ void init_wait_entry(struct wait_queue_entry *wq_entry, int flags)
wq_entry->flags = flags;
wq_entry->private = current;
wq_entry->func = autoremove_wake_function;
INIT_LIST_HEAD(&wq_entry->task_list);
INIT_LIST_HEAD(&wq_entry->entry);
}
EXPORT_SYMBOL(init_wait_entry);
@ -225,10 +225,10 @@ long prepare_to_wait_event(struct wait_queue_head *wq_head, struct wait_queue_en
* can't see us, it should wake up another exclusive waiter if
* we fail.
*/
list_del_init(&wq_entry->task_list);
list_del_init(&wq_entry->entry);
ret = -ERESTARTSYS;
} else {
if (list_empty(&wq_entry->task_list)) {
if (list_empty(&wq_entry->entry)) {
if (wq_entry->flags & WQ_FLAG_EXCLUSIVE)
__add_wait_queue_entry_tail(wq_head, wq_entry);
else
@ -251,7 +251,7 @@ EXPORT_SYMBOL(prepare_to_wait_event);
*/
int do_wait_intr(wait_queue_head_t *wq, wait_queue_entry_t *wait)
{
if (likely(list_empty(&wait->task_list)))
if (likely(list_empty(&wait->entry)))
__add_wait_queue_entry_tail(wq, wait);
set_current_state(TASK_INTERRUPTIBLE);
@ -267,7 +267,7 @@ EXPORT_SYMBOL(do_wait_intr);
int do_wait_intr_irq(wait_queue_head_t *wq, wait_queue_entry_t *wait)
{
if (likely(list_empty(&wait->task_list)))
if (likely(list_empty(&wait->entry)))
__add_wait_queue_entry_tail(wq, wait);
set_current_state(TASK_INTERRUPTIBLE);
@ -308,9 +308,9 @@ void finish_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_en
* have _one_ other CPU that looks at or modifies
* the list).
*/
if (!list_empty_careful(&wq_entry->task_list)) {
if (!list_empty_careful(&wq_entry->entry)) {
spin_lock_irqsave(&wq_head->lock, flags);
list_del_init(&wq_entry->task_list);
list_del_init(&wq_entry->entry);
spin_unlock_irqrestore(&wq_head->lock, flags);
}
}
@ -321,7 +321,7 @@ int autoremove_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, i
int ret = default_wake_function(wq_entry, mode, sync, key);
if (ret)
list_del_init(&wq_entry->task_list);
list_del_init(&wq_entry->entry);
return ret;
}
EXPORT_SYMBOL(autoremove_wake_function);

4
kernel/sched/wait_bit.c
View File

@ -205,8 +205,8 @@ int __wait_on_atomic_t(struct wait_queue_head *wq_head, struct wait_bit_queue_en
.wq_entry = { \
.private = current, \
.func = wake_atomic_t_function, \
.task_list = \
LIST_HEAD_INIT((name).wq_entry.task_list), \
.entry = \
LIST_HEAD_INIT((name).wq_entry.entry), \
}, \
}

2
mm/filemap.c
View File

@ -845,7 +845,7 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q,
for (;;) {
spin_lock_irq(&q->lock);
if (likely(list_empty(&wait->task_list))) {
if (likely(list_empty(&wait->entry))) {
if (lock)
__add_wait_queue_entry_tail_exclusive(q, wait);
else

2
mm/memcontrol.c
View File

@ -1570,7 +1570,7 @@ bool mem_cgroup_oom_synchronize(bool handle)
owait.wait.flags = 0;
owait.wait.func = memcg_oom_wake_function;
owait.wait.private = current;
INIT_LIST_HEAD(&owait.wait.task_list);
INIT_LIST_HEAD(&owait.wait.entry);
prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE);
mem_cgroup_mark_under_oom(memcg);

4
mm/shmem.c
View File

@ -1905,7 +1905,7 @@ alloc_nohuge: page = shmem_alloc_and_acct_page(gfp, info, sbinfo,
static int synchronous_wake_function(wait_queue_entry_t *wait, unsigned mode, int sync, void *key)
{
int ret = default_wake_function(wait, mode, sync, key);
list_del_init(&wait->task_list);
list_del_init(&wait->entry);
return ret;
}
@ -2840,7 +2840,7 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset,
spin_lock(&inode->i_lock);
inode->i_private = NULL;
wake_up_all(&shmem_falloc_waitq);
WARN_ON_ONCE(!list_empty(&shmem_falloc_waitq.task_list));
WARN_ON_ONCE(!list_empty(&shmem_falloc_waitq.head));
spin_unlock(&inode->i_lock);
error = 0;
goto out;