From 2055da97389a605c8a00d163d40903afbe413921 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 20 Jun 2017 12:06:46 +0200 Subject: 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 Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- mm/filemap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/filemap.c') 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 -- cgit v1.2.3-55-g7522