if (req->file && !io_req_ffs_set(req))
req->flags |= io_file_get_flags(req->file) << REQ_F_SUPPORT_NOWAIT_BIT;
- if (req->flags & REQ_F_ISREG) {
+ if (req->file && (req->flags & REQ_F_ISREG)) {
bool should_hash = def->hash_reg_file;
/* don't serialize this request if the fs doesn't need it */
io_cqring_wake(ctx);
}
-static inline void __io_cq_unlock_post_flush(struct io_ring_ctx *ctx)
+static void __io_cq_unlock_post_flush(struct io_ring_ctx *ctx)
__releases(ctx->completion_lock)
{
io_commit_cqring(ctx);
- __io_cq_unlock(ctx);
- io_commit_cqring_flush(ctx);
- /*
- * As ->task_complete implies that the ring is single tasked, cq_wait
- * may only be waited on by the current in io_cqring_wait(), but since
- * it will re-check the wakeup conditions once we return we can safely
- * skip waking it up.
- */
- if (!(ctx->flags & IORING_SETUP_DEFER_TASKRUN)) {
- smp_mb();
- __io_cqring_wake(ctx);
+ if (ctx->task_complete) {
+ /*
+ * ->task_complete implies that only current might be waiting
+ * for CQEs, and obviously, we currently don't. No one is
+ * waiting, wakeups are futile, skip them.
+ */
+ io_commit_cqring_flush(ctx);
+ } else {
+ __io_cq_unlock(ctx);
+ io_commit_cqring_flush(ctx);
+ io_cqring_wake(ctx);
}
}
}
}
-static void io_req_local_work_add(struct io_kiocb *req)
+static void io_req_local_work_add(struct io_kiocb *req, unsigned flags)
{
struct io_ring_ctx *ctx = req->ctx;
+ unsigned nr_wait, nr_tw, nr_tw_prev;
+ struct llist_node *first;
- if (!llist_add(&req->io_task_work.node, &ctx->work_llist))
- return;
+ if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK))
+ flags &= ~IOU_F_TWQ_LAZY_WAKE;
- /* needed for the following wake up */
- smp_mb__after_atomic();
-
- if (unlikely(atomic_read(&req->task->io_uring->in_cancel))) {
- io_move_task_work_from_local(ctx);
- return;
+ first = READ_ONCE(ctx->work_llist.first);
+ do {
+ nr_tw_prev = 0;
+ if (first) {
+ struct io_kiocb *first_req = container_of(first,
+ struct io_kiocb,
+ io_task_work.node);
+ /*
+ * Might be executed at any moment, rely on
+ * SLAB_TYPESAFE_BY_RCU to keep it alive.
+ */
+ nr_tw_prev = READ_ONCE(first_req->nr_tw);
+ }
+ nr_tw = nr_tw_prev + 1;
+ /* Large enough to fail the nr_wait comparison below */
+ if (!(flags & IOU_F_TWQ_LAZY_WAKE))
+ nr_tw = -1U;
+
+ req->nr_tw = nr_tw;
+ req->io_task_work.node.next = first;
+ } while (!try_cmpxchg(&ctx->work_llist.first, &first,
+ &req->io_task_work.node));
+
+ if (!first) {
+ if (ctx->flags & IORING_SETUP_TASKRUN_FLAG)
+ atomic_or(IORING_SQ_TASKRUN, &ctx->rings->sq_flags);
+ if (ctx->has_evfd)
+ io_eventfd_signal(ctx);
}
- if (ctx->flags & IORING_SETUP_TASKRUN_FLAG)
- atomic_or(IORING_SQ_TASKRUN, &ctx->rings->sq_flags);
- if (ctx->has_evfd)
- io_eventfd_signal(ctx);
-
- if (READ_ONCE(ctx->cq_waiting))
- wake_up_state(ctx->submitter_task, TASK_INTERRUPTIBLE);
+ nr_wait = atomic_read(&ctx->cq_wait_nr);
+ /* no one is waiting */
+ if (!nr_wait)
+ return;
+ /* either not enough or the previous add has already woken it up */
+ if (nr_wait > nr_tw || nr_tw_prev >= nr_wait)
+ return;
+ /* pairs with set_current_state() in io_cqring_wait() */
+ smp_mb__after_atomic();
+ wake_up_state(ctx->submitter_task, TASK_INTERRUPTIBLE);
}
-void __io_req_task_work_add(struct io_kiocb *req, bool allow_local)
+void __io_req_task_work_add(struct io_kiocb *req, unsigned flags)
{
struct io_uring_task *tctx = req->task->io_uring;
struct io_ring_ctx *ctx = req->ctx;
- if (allow_local && ctx->flags & IORING_SETUP_DEFER_TASKRUN) {
+ if (!(flags & IOU_F_TWQ_FORCE_NORMAL) &&
+ (ctx->flags & IORING_SETUP_DEFER_TASKRUN)) {
rcu_read_lock();
- io_req_local_work_add(req);
+ io_req_local_work_add(req, flags);
rcu_read_unlock();
return;
}
io_task_work.node);
node = node->next;
- __io_req_task_work_add(req, false);
+ __io_req_task_work_add(req, IOU_F_TWQ_FORCE_NORMAL);
}
}
unsigned long check_cq;
if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) {
- WRITE_ONCE(ctx->cq_waiting, 1);
+ int nr_wait = (int) iowq.cq_tail - READ_ONCE(ctx->rings->cq.tail);
+
+ atomic_set(&ctx->cq_wait_nr, nr_wait);
set_current_state(TASK_INTERRUPTIBLE);
} else {
prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq,
ret = io_cqring_wait_schedule(ctx, &iowq);
__set_current_state(TASK_RUNNING);
- WRITE_ONCE(ctx->cq_waiting, 0);
+ atomic_set(&ctx->cq_wait_nr, 0);
if (ret < 0)
break;
enum io_wq_cancel cret;
bool ret = false;
+ /* set it so io_req_local_work_add() would wake us up */
+ if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) {
+ atomic_set(&ctx->cq_wait_nr, 1);
+ smp_mb();
+ }
+
/* failed during ring init, it couldn't have issued any requests */
if (!ctx->rings)
return false;
{
struct io_uring_task *tctx = current->io_uring;
struct io_ring_ctx *ctx;
+ struct io_tctx_node *node;
+ unsigned long index;
s64 inflight;
DEFINE_WAIT(wait);
break;
if (!sqd) {
- struct io_tctx_node *node;
- unsigned long index;
-
xa_for_each(&tctx->xa, index, node) {
/* sqpoll task will cancel all its requests */
if (node->ctx->sq_data)
prepare_to_wait(&tctx->wait, &wait, TASK_INTERRUPTIBLE);
io_run_task_work();
io_uring_drop_tctx_refs(current);
-
+ xa_for_each(&tctx->xa, index, node) {
+ if (!llist_empty(&node->ctx->work_llist)) {
+ WARN_ON_ONCE(node->ctx->submitter_task &&
+ node->ctx->submitter_task != current);
+ goto end_wait;
+ }
+ }
/*
* If we've seen completions, retry without waiting. This
* avoids a race where a completion comes in before we did
*/
if (inflight == tctx_inflight(tctx, !cancel_all))
schedule();
+end_wait:
finish_wait(&tctx->wait, &wait);
} while (1);
io_uring_optable_init();
req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
- SLAB_ACCOUNT);
+ SLAB_ACCOUNT | SLAB_TYPESAFE_BY_RCU);
return 0;
};
__initcall(io_uring_init);
projects / platform / kernel / linux-starfive.git / blobdiff