diff options
| author | Ingo Molnar <mingo@kernel.org> | 2017-06-20 12:06:46 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-06-20 12:19:14 +0200 |
| commit | 2055da97389a605c8a00d163d40903afbe413921 (patch) | |
| tree | 6aec7243076aab2d4d239f03e34598752ce1512a /mm | |
| parent | 5822a454d6d22297c5fcd66264120587b2ec21cd (diff) | |
sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming
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>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/filemap.c | 2 | ||||
| -rw-r--r-- | mm/memcontrol.c | 2 | ||||
| -rw-r--r-- | mm/shmem.c | 4 |
3 files changed, 4 insertions, 4 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index 80c19ee81e95..926484561624 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -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 diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9a90b096dc6b..d75b38b66ef6 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -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); diff --git a/mm/shmem.c b/mm/shmem.c index a6c7dece4660..fdc413f82a99 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1905,7 +1905,7 @@ unlock: 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; |