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| 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 /block/kyber-iosched.c | |
| parent | 5822a454d6d22297c5fcd66264120587b2ec21cd (diff) | |
| download | lwn-2055da97389a605c8a00d163d40903afbe413921.tar.gz lwn-2055da97389a605c8a00d163d40903afbe413921.zip | |
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 'block/kyber-iosched.c')
| -rw-r--r-- | block/kyber-iosched.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c index b95d6bd714c0..9bf1484365b2 100644 --- a/block/kyber-iosched.c +++ b/block/kyber-iosched.c @@ -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) |