diff options
Diffstat (limited to 'fs')
-rw-r--r-- | fs/io-wq.c | 108 | ||||
-rw-r--r-- | fs/io-wq.h | 4 | ||||
-rw-r--r-- | fs/io_uring.c | 177 |
3 files changed, 177 insertions, 112 deletions
diff --git a/fs/io-wq.c b/fs/io-wq.c index 0b65a912b036..47c5f3aeb460 100644 --- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -903,13 +903,15 @@ void io_wq_cancel_all(struct io_wq *wq) struct io_cb_cancel_data { work_cancel_fn *fn; void *data; + int nr_running; + int nr_pending; + bool cancel_all; }; static bool io_wq_worker_cancel(struct io_worker *worker, void *data) { struct io_cb_cancel_data *match = data; unsigned long flags; - bool ret = false; /* * Hold the lock to avoid ->cur_work going out of scope, caller @@ -920,74 +922,90 @@ static bool io_wq_worker_cancel(struct io_worker *worker, void *data) !(worker->cur_work->flags & IO_WQ_WORK_NO_CANCEL) && match->fn(worker->cur_work, match->data)) { send_sig(SIGINT, worker->task, 1); - ret = true; + match->nr_running++; } spin_unlock_irqrestore(&worker->lock, flags); - return ret; + return match->nr_running && !match->cancel_all; } -static enum io_wq_cancel io_wqe_cancel_work(struct io_wqe *wqe, - struct io_cb_cancel_data *match) +static void io_wqe_cancel_pending_work(struct io_wqe *wqe, + struct io_cb_cancel_data *match) { struct io_wq_work_node *node, *prev; struct io_wq_work *work; unsigned long flags; - bool found = false; - /* - * First check pending list, if we're lucky we can just remove it - * from there. CANCEL_OK means that the work is returned as-new, - * no completion will be posted for it. - */ +retry: spin_lock_irqsave(&wqe->lock, flags); wq_list_for_each(node, prev, &wqe->work_list) { work = container_of(node, struct io_wq_work, list); + if (!match->fn(work, match->data)) + continue; - if (match->fn(work, match->data)) { - wq_list_del(&wqe->work_list, node, prev); - found = true; - break; - } - } - spin_unlock_irqrestore(&wqe->lock, flags); - - if (found) { + wq_list_del(&wqe->work_list, node, prev); + spin_unlock_irqrestore(&wqe->lock, flags); io_run_cancel(work, wqe); - return IO_WQ_CANCEL_OK; + match->nr_pending++; + if (!match->cancel_all) + return; + + /* not safe to continue after unlock */ + goto retry; } + spin_unlock_irqrestore(&wqe->lock, flags); +} - /* - * Now check if a free (going busy) or busy worker has the work - * currently running. If we find it there, we'll return CANCEL_RUNNING - * as an indication that we attempt to signal cancellation. The - * completion will run normally in this case. - */ +static void io_wqe_cancel_running_work(struct io_wqe *wqe, + struct io_cb_cancel_data *match) +{ rcu_read_lock(); - found = io_wq_for_each_worker(wqe, io_wq_worker_cancel, match); + io_wq_for_each_worker(wqe, io_wq_worker_cancel, match); rcu_read_unlock(); - return found ? IO_WQ_CANCEL_RUNNING : IO_WQ_CANCEL_NOTFOUND; } enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel, - void *data) + void *data, bool cancel_all) { struct io_cb_cancel_data match = { - .fn = cancel, - .data = data, + .fn = cancel, + .data = data, + .cancel_all = cancel_all, }; - enum io_wq_cancel ret = IO_WQ_CANCEL_NOTFOUND; int node; + /* + * First check pending list, if we're lucky we can just remove it + * from there. CANCEL_OK means that the work is returned as-new, + * no completion will be posted for it. + */ for_each_node(node) { struct io_wqe *wqe = wq->wqes[node]; - ret = io_wqe_cancel_work(wqe, &match); - if (ret != IO_WQ_CANCEL_NOTFOUND) - break; + io_wqe_cancel_pending_work(wqe, &match); + if (match.nr_pending && !match.cancel_all) + return IO_WQ_CANCEL_OK; } - return ret; + /* + * Now check if a free (going busy) or busy worker has the work + * currently running. If we find it there, we'll return CANCEL_RUNNING + * as an indication that we attempt to signal cancellation. The + * completion will run normally in this case. + */ + for_each_node(node) { + struct io_wqe *wqe = wq->wqes[node]; + + io_wqe_cancel_running_work(wqe, &match); + if (match.nr_running && !match.cancel_all) + return IO_WQ_CANCEL_RUNNING; + } + + if (match.nr_running) + return IO_WQ_CANCEL_RUNNING; + if (match.nr_pending) + return IO_WQ_CANCEL_OK; + return IO_WQ_CANCEL_NOTFOUND; } static bool io_wq_io_cb_cancel_data(struct io_wq_work *work, void *data) @@ -997,21 +1015,7 @@ static bool io_wq_io_cb_cancel_data(struct io_wq_work *work, void *data) enum io_wq_cancel io_wq_cancel_work(struct io_wq *wq, struct io_wq_work *cwork) { - return io_wq_cancel_cb(wq, io_wq_io_cb_cancel_data, (void *)cwork); -} - -static bool io_wq_pid_match(struct io_wq_work *work, void *data) -{ - pid_t pid = (pid_t) (unsigned long) data; - - return work->task_pid == pid; -} - -enum io_wq_cancel io_wq_cancel_pid(struct io_wq *wq, pid_t pid) -{ - void *data = (void *) (unsigned long) pid; - - return io_wq_cancel_cb(wq, io_wq_pid_match, data); + return io_wq_cancel_cb(wq, io_wq_io_cb_cancel_data, (void *)cwork, false); } struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data) diff --git a/fs/io-wq.h b/fs/io-wq.h index 8e138fa88b9f..071f1a997800 100644 --- a/fs/io-wq.h +++ b/fs/io-wq.h @@ -90,7 +90,6 @@ struct io_wq_work { const struct cred *creds; struct fs_struct *fs; unsigned flags; - pid_t task_pid; }; static inline struct io_wq_work *wq_next_work(struct io_wq_work *work) @@ -125,12 +124,11 @@ static inline bool io_wq_is_hashed(struct io_wq_work *work) void io_wq_cancel_all(struct io_wq *wq); enum io_wq_cancel io_wq_cancel_work(struct io_wq *wq, struct io_wq_work *cwork); -enum io_wq_cancel io_wq_cancel_pid(struct io_wq *wq, pid_t pid); typedef bool (work_cancel_fn)(struct io_wq_work *, void *); enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel, - void *data); + void *data, bool cancel_all); struct task_struct *io_wq_get_task(struct io_wq *wq); diff --git a/fs/io_uring.c b/fs/io_uring.c index 155f3d830ddb..a78201b96179 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -541,6 +541,7 @@ enum { REQ_F_NO_FILE_TABLE_BIT, REQ_F_QUEUE_TIMEOUT_BIT, REQ_F_WORK_INITIALIZED_BIT, + REQ_F_TASK_PINNED_BIT, /* not a real bit, just to check we're not overflowing the space */ __REQ_F_LAST_BIT, @@ -598,6 +599,8 @@ enum { REQ_F_QUEUE_TIMEOUT = BIT(REQ_F_QUEUE_TIMEOUT_BIT), /* io_wq_work is initialized */ REQ_F_WORK_INITIALIZED = BIT(REQ_F_WORK_INITIALIZED_BIT), + /* req->task is refcounted */ + REQ_F_TASK_PINNED = BIT(REQ_F_TASK_PINNED_BIT), }; struct async_poll { @@ -910,6 +913,21 @@ struct sock *io_uring_get_socket(struct file *file) } EXPORT_SYMBOL(io_uring_get_socket); +static void io_get_req_task(struct io_kiocb *req) +{ + if (req->flags & REQ_F_TASK_PINNED) + return; + get_task_struct(req->task); + req->flags |= REQ_F_TASK_PINNED; +} + +/* not idempotent -- it doesn't clear REQ_F_TASK_PINNED */ +static void __io_put_req_task(struct io_kiocb *req) +{ + if (req->flags & REQ_F_TASK_PINNED) + put_task_struct(req->task); +} + static void io_file_put_work(struct work_struct *work); /* @@ -1045,8 +1063,6 @@ static inline void io_req_work_grab_env(struct io_kiocb *req, } spin_unlock(¤t->fs->lock); } - if (!req->work.task_pid) - req->work.task_pid = task_pid_vnr(current); } static inline void io_req_work_drop_env(struct io_kiocb *req) @@ -1087,6 +1103,7 @@ static inline void io_prep_async_work(struct io_kiocb *req, req->work.flags |= IO_WQ_WORK_UNBOUND; } + io_req_init_async(req); io_req_work_grab_env(req, def); *link = io_prep_linked_timeout(req); @@ -1398,9 +1415,7 @@ static void __io_req_aux_free(struct io_kiocb *req) kfree(req->io); if (req->file) io_put_file(req, req->file, (req->flags & REQ_F_FIXED_FILE)); - if (req->task) - put_task_struct(req->task); - + __io_put_req_task(req); io_req_work_drop_env(req); } @@ -1727,6 +1742,18 @@ static int io_put_kbuf(struct io_kiocb *req) return cflags; } +static void io_iopoll_queue(struct list_head *again) +{ + struct io_kiocb *req; + + do { + req = list_first_entry(again, struct io_kiocb, list); + list_del(&req->list); + refcount_inc(&req->refs); + io_queue_async_work(req); + } while (!list_empty(again)); +} + /* * Find and free completed poll iocbs */ @@ -1735,12 +1762,21 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events, { struct req_batch rb; struct io_kiocb *req; + LIST_HEAD(again); + + /* order with ->result store in io_complete_rw_iopoll() */ + smp_rmb(); rb.to_free = rb.need_iter = 0; while (!list_empty(done)) { int cflags = 0; req = list_first_entry(done, struct io_kiocb, list); + if (READ_ONCE(req->result) == -EAGAIN) { + req->iopoll_completed = 0; + list_move_tail(&req->list, &again); + continue; + } list_del(&req->list); if (req->flags & REQ_F_BUFFER_SELECTED) @@ -1758,18 +1794,9 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events, if (ctx->flags & IORING_SETUP_SQPOLL) io_cqring_ev_posted(ctx); io_free_req_many(ctx, &rb); -} -static void io_iopoll_queue(struct list_head *again) -{ - struct io_kiocb *req; - - do { - req = list_first_entry(again, struct io_kiocb, list); - list_del(&req->list); - refcount_inc(&req->refs); - io_queue_async_work(req); - } while (!list_empty(again)); + if (!list_empty(&again)) + io_iopoll_queue(&again); } static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, @@ -1777,7 +1804,6 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, { struct io_kiocb *req, *tmp; LIST_HEAD(done); - LIST_HEAD(again); bool spin; int ret; @@ -1803,13 +1829,6 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, if (!list_empty(&done)) break; - if (req->result == -EAGAIN) { - list_move_tail(&req->list, &again); - continue; - } - if (!list_empty(&again)) - break; - ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin); if (ret < 0) break; @@ -1822,9 +1841,6 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, if (!list_empty(&done)) io_iopoll_complete(ctx, nr_events, &done); - if (!list_empty(&again)) - io_iopoll_queue(&again); - return ret; } @@ -1973,11 +1989,15 @@ static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2) if (kiocb->ki_flags & IOCB_WRITE) kiocb_end_write(req); - if (res != req->result) + if (res != -EAGAIN && res != req->result) req_set_fail_links(req); - req->result = res; - if (res != -EAGAIN) + + WRITE_ONCE(req->result, res); + /* order with io_poll_complete() checking ->result */ + if (res != -EAGAIN) { + smp_wmb(); WRITE_ONCE(req->iopoll_completed, 1); + } } /* @@ -2650,8 +2670,8 @@ copy_iov: } } out_free: - kfree(iovec); - req->flags &= ~REQ_F_NEED_CLEANUP; + if (!(req->flags & REQ_F_NEED_CLEANUP)) + kfree(iovec); return ret; } @@ -2773,8 +2793,8 @@ copy_iov: } } out_free: - req->flags &= ~REQ_F_NEED_CLEANUP; - kfree(iovec); + if (!(req->flags & REQ_F_NEED_CLEANUP)) + kfree(iovec); return ret; } @@ -4236,6 +4256,28 @@ static void io_async_queue_proc(struct file *file, struct wait_queue_head *head, __io_queue_proc(&pt->req->apoll->poll, pt, head); } +static void io_sq_thread_drop_mm(struct io_ring_ctx *ctx) +{ + struct mm_struct *mm = current->mm; + + if (mm) { + kthread_unuse_mm(mm); + mmput(mm); + } +} + +static int io_sq_thread_acquire_mm(struct io_ring_ctx *ctx, + struct io_kiocb *req) +{ + if (io_op_defs[req->opcode].needs_mm && !current->mm) { + if (unlikely(!mmget_not_zero(ctx->sqo_mm))) + return -EFAULT; + kthread_use_mm(ctx->sqo_mm); + } + + return 0; +} + static void io_async_task_func(struct callback_head *cb) { struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); @@ -4270,11 +4312,16 @@ static void io_async_task_func(struct callback_head *cb) if (!canceled) { __set_current_state(TASK_RUNNING); + if (io_sq_thread_acquire_mm(ctx, req)) { + io_cqring_add_event(req, -EFAULT); + goto end_req; + } mutex_lock(&ctx->uring_lock); __io_queue_sqe(req, NULL); mutex_unlock(&ctx->uring_lock); } else { io_cqring_ev_posted(ctx); +end_req: req_set_fail_links(req); io_double_put_req(req); } @@ -4366,8 +4413,7 @@ static bool io_arm_poll_handler(struct io_kiocb *req) memcpy(&apoll->work, &req->work, sizeof(req->work)); had_io = req->io != NULL; - get_task_struct(current); - req->task = current; + io_get_req_task(req); req->apoll = apoll; INIT_HLIST_NODE(&req->hash_node); @@ -4555,8 +4601,7 @@ static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe events = READ_ONCE(sqe->poll_events); poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP; - get_task_struct(current); - req->task = current; + io_get_req_task(req); return 0; } @@ -4772,7 +4817,7 @@ static int io_async_cancel_one(struct io_ring_ctx *ctx, void *sqe_addr) enum io_wq_cancel cancel_ret; int ret = 0; - cancel_ret = io_wq_cancel_cb(ctx->io_wq, io_cancel_cb, sqe_addr); + cancel_ret = io_wq_cancel_cb(ctx->io_wq, io_cancel_cb, sqe_addr, false); switch (cancel_ret) { case IO_WQ_CANCEL_OK: ret = 0; @@ -5817,17 +5862,14 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, req->flags = 0; /* one is dropped after submission, the other at completion */ refcount_set(&req->refs, 2); - req->task = NULL; + req->task = current; req->result = 0; if (unlikely(req->opcode >= IORING_OP_LAST)) return -EINVAL; - if (io_op_defs[req->opcode].needs_mm && !current->mm) { - if (unlikely(!mmget_not_zero(ctx->sqo_mm))) - return -EFAULT; - kthread_use_mm(ctx->sqo_mm); - } + if (unlikely(io_sq_thread_acquire_mm(ctx, req))) + return -EFAULT; sqe_flags = READ_ONCE(sqe->flags); /* enforce forwards compatibility on users */ @@ -5936,16 +5978,6 @@ fail_req: return submitted; } -static inline void io_sq_thread_drop_mm(struct io_ring_ctx *ctx) -{ - struct mm_struct *mm = current->mm; - - if (mm) { - kthread_unuse_mm(mm); - mmput(mm); - } -} - static int io_sq_thread(void *data) { struct io_ring_ctx *ctx = data; @@ -7331,7 +7363,17 @@ static void io_ring_exit_work(struct work_struct *work) if (ctx->rings) io_cqring_overflow_flush(ctx, true); - wait_for_completion(&ctx->ref_comp); + /* + * If we're doing polled IO and end up having requests being + * submitted async (out-of-line), then completions can come in while + * we're waiting for refs to drop. We need to reap these manually, + * as nobody else will be looking for them. + */ + while (!wait_for_completion_timeout(&ctx->ref_comp, HZ/20)) { + io_iopoll_reap_events(ctx); + if (ctx->rings) + io_cqring_overflow_flush(ctx, true); + } io_ring_ctx_free(ctx); } @@ -7365,9 +7407,22 @@ static int io_uring_release(struct inode *inode, struct file *file) return 0; } +static bool io_wq_files_match(struct io_wq_work *work, void *data) +{ + struct files_struct *files = data; + + return work->files == files; +} + static void io_uring_cancel_files(struct io_ring_ctx *ctx, struct files_struct *files) { + if (list_empty_careful(&ctx->inflight_list)) + return; + + /* cancel all at once, should be faster than doing it one by one*/ + io_wq_cancel_cb(ctx->io_wq, io_wq_files_match, files, true); + while (!list_empty_careful(&ctx->inflight_list)) { struct io_kiocb *cancel_req = NULL, *req; DEFINE_WAIT(wait); @@ -7423,6 +7478,14 @@ static void io_uring_cancel_files(struct io_ring_ctx *ctx, } } +static bool io_cancel_task_cb(struct io_wq_work *work, void *data) +{ + struct io_kiocb *req = container_of(work, struct io_kiocb, work); + struct task_struct *task = data; + + return req->task == task; +} + static int io_uring_flush(struct file *file, void *data) { struct io_ring_ctx *ctx = file->private_data; @@ -7433,7 +7496,7 @@ static int io_uring_flush(struct file *file, void *data) * If the task is going away, cancel work it may have pending */ if (fatal_signal_pending(current) || (current->flags & PF_EXITING)) - io_wq_cancel_pid(ctx->io_wq, task_pid_vnr(current)); + io_wq_cancel_cb(ctx->io_wq, io_cancel_task_cb, current, true); return 0; } |