diff options
Diffstat (limited to 'io_uring')
-rw-r--r-- | io_uring/fdinfo.c | 16 | ||||
-rw-r--r-- | io_uring/io-wq.c | 4 | ||||
-rw-r--r-- | io_uring/io_uring.c | 91 | ||||
-rw-r--r-- | io_uring/kbuf.c | 8 | ||||
-rw-r--r-- | io_uring/kbuf.h | 1 | ||||
-rw-r--r-- | io_uring/msg_ring.c | 1 | ||||
-rw-r--r-- | io_uring/net.c | 46 | ||||
-rw-r--r-- | io_uring/refs.h | 7 | ||||
-rw-r--r-- | io_uring/register.c | 7 | ||||
-rw-r--r-- | io_uring/rsrc.c | 23 | ||||
-rw-r--r-- | io_uring/rsrc.h | 1 | ||||
-rw-r--r-- | io_uring/sqpoll.c | 50 | ||||
-rw-r--r-- | io_uring/sqpoll.h | 8 |
13 files changed, 171 insertions, 92 deletions
diff --git a/io_uring/fdinfo.c b/io_uring/fdinfo.c index 6b1247664b35..c6c624eb9866 100644 --- a/io_uring/fdinfo.c +++ b/io_uring/fdinfo.c @@ -83,11 +83,11 @@ __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *file) seq_printf(m, "SqMask:\t0x%x\n", sq_mask); seq_printf(m, "SqHead:\t%u\n", sq_head); seq_printf(m, "SqTail:\t%u\n", sq_tail); - seq_printf(m, "CachedSqHead:\t%u\n", ctx->cached_sq_head); + seq_printf(m, "CachedSqHead:\t%u\n", data_race(ctx->cached_sq_head)); seq_printf(m, "CqMask:\t0x%x\n", cq_mask); seq_printf(m, "CqHead:\t%u\n", cq_head); seq_printf(m, "CqTail:\t%u\n", cq_tail); - seq_printf(m, "CachedCqTail:\t%u\n", ctx->cached_cq_tail); + seq_printf(m, "CachedCqTail:\t%u\n", data_race(ctx->cached_cq_tail)); seq_printf(m, "SQEs:\t%u\n", sq_tail - sq_head); sq_entries = min(sq_tail - sq_head, ctx->sq_entries); for (i = 0; i < sq_entries; i++) { @@ -146,18 +146,26 @@ __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *file) if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) { struct io_sq_data *sq = ctx->sq_data; + struct task_struct *tsk; + rcu_read_lock(); + tsk = rcu_dereference(sq->thread); /* * sq->thread might be NULL if we raced with the sqpoll * thread termination. */ - if (sq->thread) { + if (tsk) { + get_task_struct(tsk); + rcu_read_unlock(); + getrusage(tsk, RUSAGE_SELF, &sq_usage); + put_task_struct(tsk); sq_pid = sq->task_pid; sq_cpu = sq->sq_cpu; - getrusage(sq->thread, RUSAGE_SELF, &sq_usage); sq_total_time = (sq_usage.ru_stime.tv_sec * 1000000 + sq_usage.ru_stime.tv_usec); sq_work_time = sq->work_time; + } else { + rcu_read_unlock(); } } diff --git a/io_uring/io-wq.c b/io_uring/io-wq.c index a2d577b09930..8f555c1d7185 100644 --- a/io_uring/io-wq.c +++ b/io_uring/io-wq.c @@ -1204,8 +1204,10 @@ struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data) atomic_set(&wq->worker_refs, 1); init_completion(&wq->worker_done); ret = cpuhp_state_add_instance_nocalls(io_wq_online, &wq->cpuhp_node); - if (ret) + if (ret) { + put_task_struct(wq->task); goto err; + } return wq; err: diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 19de7129ae0b..52ada466bf98 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -441,24 +441,6 @@ static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req) return req->link; } -static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req) -{ - if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT))) - return NULL; - return __io_prep_linked_timeout(req); -} - -static noinline void __io_arm_ltimeout(struct io_kiocb *req) -{ - io_queue_linked_timeout(__io_prep_linked_timeout(req)); -} - -static inline void io_arm_ltimeout(struct io_kiocb *req) -{ - if (unlikely(req->flags & REQ_F_ARM_LTIMEOUT)) - __io_arm_ltimeout(req); -} - static void io_prep_async_work(struct io_kiocb *req) { const struct io_issue_def *def = &io_issue_defs[req->opcode]; @@ -511,7 +493,6 @@ static void io_prep_async_link(struct io_kiocb *req) static void io_queue_iowq(struct io_kiocb *req) { - struct io_kiocb *link = io_prep_linked_timeout(req); struct io_uring_task *tctx = req->task->io_uring; BUG_ON(!tctx); @@ -536,8 +517,6 @@ static void io_queue_iowq(struct io_kiocb *req) trace_io_uring_queue_async_work(req, io_wq_is_hashed(&req->work)); io_wq_enqueue(tctx->io_wq, &req->work); - if (link) - io_queue_linked_timeout(link); } static void io_req_queue_iowq_tw(struct io_kiocb *req, struct io_tw_state *ts) @@ -651,6 +630,7 @@ static void __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool dying) * to care for a non-real case. */ if (need_resched()) { + ctx->cqe_sentinel = ctx->cqe_cached; io_cq_unlock_post(ctx); mutex_unlock(&ctx->uring_lock); cond_resched(); @@ -884,13 +864,26 @@ bool io_req_post_cqe(struct io_kiocb *req, s32 res, u32 cflags) struct io_ring_ctx *ctx = req->ctx; bool posted; + /* + * If multishot has already posted deferred completions, ensure that + * those are flushed first before posting this one. If not, CQEs + * could get reordered. + */ + if (!wq_list_empty(&ctx->submit_state.compl_reqs)) + __io_submit_flush_completions(ctx); + lockdep_assert(!io_wq_current_is_worker()); lockdep_assert_held(&ctx->uring_lock); - __io_cq_lock(ctx); - posted = io_fill_cqe_aux(ctx, req->cqe.user_data, res, cflags); + if (!ctx->lockless_cq) { + spin_lock(&ctx->completion_lock); + posted = io_fill_cqe_aux(ctx, req->cqe.user_data, res, cflags); + spin_unlock(&ctx->completion_lock); + } else { + posted = io_fill_cqe_aux(ctx, req->cqe.user_data, res, cflags); + } + ctx->submit_state.cq_flush = true; - __io_cq_unlock_post(ctx); return posted; } @@ -1103,21 +1096,22 @@ static __cold void io_fallback_tw(struct io_uring_task *tctx, bool sync) while (node) { req = container_of(node, struct io_kiocb, io_task_work.node); node = node->next; - if (sync && last_ctx != req->ctx) { + if (last_ctx != req->ctx) { if (last_ctx) { - flush_delayed_work(&last_ctx->fallback_work); + if (sync) + flush_delayed_work(&last_ctx->fallback_work); percpu_ref_put(&last_ctx->refs); } last_ctx = req->ctx; percpu_ref_get(&last_ctx->refs); } - if (llist_add(&req->io_task_work.node, - &req->ctx->fallback_llist)) - schedule_delayed_work(&req->ctx->fallback_work, 1); + if (llist_add(&req->io_task_work.node, &last_ctx->fallback_llist)) + schedule_delayed_work(&last_ctx->fallback_work, 1); } if (last_ctx) { - flush_delayed_work(&last_ctx->fallback_work); + if (sync) + flush_delayed_work(&last_ctx->fallback_work); percpu_ref_put(&last_ctx->refs); } } @@ -1687,7 +1681,7 @@ queue: spin_unlock(&ctx->completion_lock); io_prep_async_link(req); - de = kmalloc(sizeof(*de), GFP_KERNEL); + de = kmalloc(sizeof(*de), GFP_KERNEL_ACCOUNT); if (!de) { ret = -ENOMEM; io_req_defer_failed(req, ret); @@ -1722,17 +1716,24 @@ static bool io_assign_file(struct io_kiocb *req, const struct io_issue_def *def, return !!req->file; } +#define REQ_ISSUE_SLOW_FLAGS (REQ_F_CREDS | REQ_F_ARM_LTIMEOUT) + static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) { const struct io_issue_def *def = &io_issue_defs[req->opcode]; const struct cred *creds = NULL; + struct io_kiocb *link = NULL; int ret; if (unlikely(!io_assign_file(req, def, issue_flags))) return -EBADF; - if (unlikely((req->flags & REQ_F_CREDS) && req->creds != current_cred())) - creds = override_creds(req->creds); + if (unlikely(req->flags & REQ_ISSUE_SLOW_FLAGS)) { + if ((req->flags & REQ_F_CREDS) && req->creds != current_cred()) + creds = override_creds(req->creds); + if (req->flags & REQ_F_ARM_LTIMEOUT) + link = __io_prep_linked_timeout(req); + } if (!def->audit_skip) audit_uring_entry(req->opcode); @@ -1742,8 +1743,12 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) if (!def->audit_skip) audit_uring_exit(!ret, ret); - if (creds) - revert_creds(creds); + if (unlikely(creds || link)) { + if (creds) + revert_creds(creds); + if (link) + io_queue_linked_timeout(link); + } if (ret == IOU_OK) { if (issue_flags & IO_URING_F_COMPLETE_DEFER) @@ -1756,7 +1761,6 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) if (ret == IOU_ISSUE_SKIP_COMPLETE) { ret = 0; - io_arm_ltimeout(req); /* If the op doesn't have a file, we're not polling for it */ if ((req->ctx->flags & IORING_SETUP_IOPOLL) && def->iopoll_queue) @@ -1777,7 +1781,7 @@ struct io_wq_work *io_wq_free_work(struct io_wq_work *work) struct io_kiocb *req = container_of(work, struct io_kiocb, work); struct io_kiocb *nxt = NULL; - if (req_ref_put_and_test(req)) { + if (req_ref_put_and_test_atomic(req)) { if (req->flags & IO_REQ_LINK_FLAGS) nxt = io_req_find_next(req); io_free_req(req); @@ -1799,8 +1803,6 @@ void io_wq_submit_work(struct io_wq_work *work) else req_ref_get(req); - io_arm_ltimeout(req); - /* either cancelled or io-wq is dying, so don't touch tctx->iowq */ if (atomic_read(&work->flags) & IO_WQ_WORK_CANCEL) { fail: @@ -1920,15 +1922,11 @@ struct file *io_file_get_normal(struct io_kiocb *req, int fd) static void io_queue_async(struct io_kiocb *req, int ret) __must_hold(&req->ctx->uring_lock) { - struct io_kiocb *linked_timeout; - if (ret != -EAGAIN || (req->flags & REQ_F_NOWAIT)) { io_req_defer_failed(req, ret); return; } - linked_timeout = io_prep_linked_timeout(req); - switch (io_arm_poll_handler(req, 0)) { case IO_APOLL_READY: io_kbuf_recycle(req, 0); @@ -1941,9 +1939,6 @@ static void io_queue_async(struct io_kiocb *req, int ret) case IO_APOLL_OK: break; } - - if (linked_timeout) - io_queue_linked_timeout(linked_timeout); } static inline void io_queue_sqe(struct io_kiocb *req) @@ -2921,7 +2916,7 @@ static __cold void io_ring_exit_work(struct work_struct *work) struct task_struct *tsk; io_sq_thread_park(sqd); - tsk = sqd->thread; + tsk = sqpoll_task_locked(sqd); if (tsk && tsk->io_uring && tsk->io_uring->io_wq) io_wq_cancel_cb(tsk->io_uring->io_wq, io_cancel_ctx_cb, ctx, true); @@ -3158,7 +3153,7 @@ __cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd) s64 inflight; DEFINE_WAIT(wait); - WARN_ON_ONCE(sqd && sqd->thread != current); + WARN_ON_ONCE(sqd && sqpoll_task_locked(sqd) != current); if (!current->io_uring) return; diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c index 7a8c3a004800..9bd27deeee6f 100644 --- a/io_uring/kbuf.c +++ b/io_uring/kbuf.c @@ -262,8 +262,12 @@ static int io_ring_buffers_peek(struct io_kiocb *req, struct buf_sel_arg *arg, /* truncate end piece, if needed, for non partial buffers */ if (len > arg->max_len) { len = arg->max_len; - if (!(bl->flags & IOBL_INC)) + if (!(bl->flags & IOBL_INC)) { + arg->partial_map = 1; + if (iov != arg->iovs) + break; buf->len = len; + } } iov->iov_base = u64_to_user_ptr(buf->addr); @@ -728,7 +732,7 @@ int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg) io_destroy_bl(ctx, bl); } - free_bl = bl = kzalloc(sizeof(*bl), GFP_KERNEL); + free_bl = bl = kzalloc(sizeof(*bl), GFP_KERNEL_ACCOUNT); if (!bl) return -ENOMEM; diff --git a/io_uring/kbuf.h b/io_uring/kbuf.h index 36aadfe5ac00..2586a292dfb9 100644 --- a/io_uring/kbuf.h +++ b/io_uring/kbuf.h @@ -61,6 +61,7 @@ struct buf_sel_arg { size_t max_len; unsigned short nr_iovs; unsigned short mode; + unsigned short partial_map; }; void __user *io_buffer_select(struct io_kiocb *req, size_t *len, diff --git a/io_uring/msg_ring.c b/io_uring/msg_ring.c index 7fd9badcfaf8..35b1b585e9cb 100644 --- a/io_uring/msg_ring.c +++ b/io_uring/msg_ring.c @@ -94,6 +94,7 @@ static int io_msg_remote_post(struct io_ring_ctx *ctx, struct io_kiocb *req, kmem_cache_free(req_cachep, req); return -EOWNERDEAD; } + req->opcode = IORING_OP_NOP; req->cqe.user_data = user_data; io_req_set_res(req, res, cflags); percpu_ref_get(&ctx->refs); diff --git a/io_uring/net.c b/io_uring/net.c index 384915d931b7..0116cfaec848 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -76,12 +76,18 @@ struct io_sr_msg { /* initialised and used only by !msg send variants */ u16 addr_len; u16 buf_group; + unsigned short retry_flags; void __user *addr; void __user *msg_control; /* used only for send zerocopy */ struct io_kiocb *notif; }; +enum sr_retry_flags { + IO_SR_MSG_RETRY = 1, + IO_SR_MSG_PARTIAL_MAP = 2, +}; + /* * Number of times we'll try and do receives if there's more data. If we * exceed this limit, then add us to the back of the queue and retry from @@ -203,6 +209,7 @@ static inline void io_mshot_prep_retry(struct io_kiocb *req, req->flags &= ~REQ_F_BL_EMPTY; sr->done_io = 0; + sr->retry_flags = 0; sr->len = 0; /* get from the provided buffer */ req->buf_index = sr->buf_group; } @@ -409,6 +416,7 @@ int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg); sr->done_io = 0; + sr->retry_flags = 0; if (req->opcode == IORING_OP_SEND) { if (READ_ONCE(sqe->__pad3[0])) @@ -780,6 +788,7 @@ int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg); sr->done_io = 0; + sr->retry_flags = 0; if (unlikely(sqe->file_index || sqe->addr2)) return -EINVAL; @@ -828,6 +837,9 @@ int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return io_recvmsg_prep_setup(req); } +/* bits to clear in old and inherit in new cflags on bundle retry */ +#define CQE_F_MASK (IORING_CQE_F_SOCK_NONEMPTY|IORING_CQE_F_MORE) + /* * Finishes io_recv and io_recvmsg. * @@ -845,11 +857,27 @@ static inline bool io_recv_finish(struct io_kiocb *req, int *ret, cflags |= IORING_CQE_F_SOCK_NONEMPTY; if (sr->flags & IORING_RECVSEND_BUNDLE) { - cflags |= io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret), + size_t this_ret = *ret - sr->done_io; + + cflags |= io_put_kbufs(req, this_ret, io_bundle_nbufs(kmsg, this_ret), issue_flags); + if (sr->retry_flags & IO_SR_MSG_RETRY) + cflags = req->cqe.flags | (cflags & CQE_F_MASK); /* bundle with no more immediate buffers, we're done */ if (req->flags & REQ_F_BL_EMPTY) goto finish; + /* + * If more is available AND it was a full transfer, retry and + * append to this one + */ + if (!sr->retry_flags && kmsg->msg.msg_inq > 1 && this_ret > 0 && + !iov_iter_count(&kmsg->msg.msg_iter)) { + req->cqe.flags = cflags & ~CQE_F_MASK; + sr->len = kmsg->msg.msg_inq; + sr->done_io += this_ret; + sr->retry_flags |= IO_SR_MSG_RETRY; + return false; + } } else { cflags |= io_put_kbuf(req, *ret, issue_flags); } @@ -1088,13 +1116,21 @@ static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg arg.mode |= KBUF_MODE_FREE; } - if (kmsg->msg.msg_inq > 0) + if (kmsg->msg.msg_inq > 1) arg.max_len = min_not_zero(sr->len, kmsg->msg.msg_inq); ret = io_buffers_peek(req, &arg); if (unlikely(ret < 0)) return ret; + if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) { + kmsg->free_iov_nr = ret; + kmsg->free_iov = arg.iovs; + req->flags |= REQ_F_NEED_CLEANUP; + } + if (arg.partial_map) + sr->retry_flags |= IO_SR_MSG_PARTIAL_MAP; + /* special case 1 vec, can be a fast path */ if (ret == 1) { sr->buf = arg.iovs[0].iov_base; @@ -1103,11 +1139,6 @@ static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg } iov_iter_init(&kmsg->msg.msg_iter, ITER_DEST, arg.iovs, ret, arg.out_len); - if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) { - kmsg->free_iov_nr = ret; - kmsg->free_iov = arg.iovs; - req->flags |= REQ_F_NEED_CLEANUP; - } } else { void __user *buf; @@ -1228,6 +1259,7 @@ int io_send_zc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) struct io_kiocb *notif; zc->done_io = 0; + zc->retry_flags = 0; req->flags |= REQ_F_POLL_NO_LAZY; if (unlikely(READ_ONCE(sqe->__pad2[0]) || READ_ONCE(sqe->addr3))) diff --git a/io_uring/refs.h b/io_uring/refs.h index 63982ead9f7d..0d928d87c4ed 100644 --- a/io_uring/refs.h +++ b/io_uring/refs.h @@ -17,6 +17,13 @@ static inline bool req_ref_inc_not_zero(struct io_kiocb *req) return atomic_inc_not_zero(&req->refs); } +static inline bool req_ref_put_and_test_atomic(struct io_kiocb *req) +{ + WARN_ON_ONCE(!(data_race(req->flags) & REQ_F_REFCOUNT)); + WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req)); + return atomic_dec_and_test(&req->refs); +} + static inline bool req_ref_put_and_test(struct io_kiocb *req) { if (likely(!(req->flags & REQ_F_REFCOUNT))) diff --git a/io_uring/register.c b/io_uring/register.c index eca26d4884d9..a325b493ae12 100644 --- a/io_uring/register.c +++ b/io_uring/register.c @@ -268,6 +268,8 @@ static __cold int io_register_iowq_max_workers(struct io_ring_ctx *ctx, if (ctx->flags & IORING_SETUP_SQPOLL) { sqd = ctx->sq_data; if (sqd) { + struct task_struct *tsk; + /* * Observe the correct sqd->lock -> ctx->uring_lock * ordering. Fine to drop uring_lock here, we hold @@ -277,8 +279,9 @@ static __cold int io_register_iowq_max_workers(struct io_ring_ctx *ctx, mutex_unlock(&ctx->uring_lock); mutex_lock(&sqd->lock); mutex_lock(&ctx->uring_lock); - if (sqd->thread) - tctx = sqd->thread->io_uring; + tsk = sqpoll_task_locked(sqd); + if (tsk) + tctx = tsk->io_uring; } } else { tctx = current->io_uring; diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index a67bae350416..1687e35e21c9 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -119,8 +119,11 @@ static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slo if (imu != &dummy_ubuf) { if (!refcount_dec_and_test(&imu->refs)) return; - for (i = 0; i < imu->nr_bvecs; i++) - unpin_user_page(imu->bvec[i].bv_page); + for (i = 0; i < imu->nr_bvecs; i++) { + struct folio *folio = page_folio(imu->bvec[i].bv_page); + + unpin_user_folio(folio, 1); + } if (imu->acct_pages) io_unaccount_mem(ctx, imu->acct_pages); kvfree(imu); @@ -915,6 +918,7 @@ static bool io_try_coalesce_buffer(struct page ***pages, int *nr_pages, return false; data->folio_shift = folio_shift(folio); + data->first_folio_page_idx = folio_page_idx(folio, page_array[0]); /* * Check if pages are contiguous inside a folio, and all folios have * the same page count except for the head and tail. @@ -983,10 +987,8 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, goto done; ret = io_buffer_account_pin(ctx, pages, nr_pages, imu, last_hpage); - if (ret) { - unpin_user_pages(pages, nr_pages); + if (ret) goto done; - } size = iov->iov_len; /* store original address for later verification */ @@ -997,7 +999,9 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, if (coalesced) imu->folio_shift = data.folio_shift; refcount_set(&imu->refs, 1); - off = (unsigned long) iov->iov_base & ((1UL << imu->folio_shift) - 1); + off = (unsigned long)iov->iov_base & ~PAGE_MASK; + if (coalesced) + off += data.first_folio_page_idx << PAGE_SHIFT; *pimu = imu; ret = 0; @@ -1010,8 +1014,13 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, size -= vec_len; } done: - if (ret) + if (ret) { kvfree(imu); + if (pages) { + for (i = 0; i < nr_pages; i++) + unpin_user_folio(page_folio(pages[i]), 1); + } + } kvfree(pages); return ret; } diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h index 8ed588036210..459cf4c6e856 100644 --- a/io_uring/rsrc.h +++ b/io_uring/rsrc.h @@ -56,6 +56,7 @@ struct io_imu_folio_data { /* For non-head/tail folios, has to be fully included */ unsigned int nr_pages_mid; unsigned int folio_shift; + unsigned long first_folio_page_idx; }; void io_rsrc_node_ref_zero(struct io_rsrc_node *node); diff --git a/io_uring/sqpoll.c b/io_uring/sqpoll.c index 5bc54c6df20f..2faa3058b2d0 100644 --- a/io_uring/sqpoll.c +++ b/io_uring/sqpoll.c @@ -20,7 +20,7 @@ #include "sqpoll.h" #define IORING_SQPOLL_CAP_ENTRIES_VALUE 8 -#define IORING_TW_CAP_ENTRIES_VALUE 8 +#define IORING_TW_CAP_ENTRIES_VALUE 32 enum { IO_SQ_THREAD_SHOULD_STOP = 0, @@ -30,7 +30,7 @@ enum { void io_sq_thread_unpark(struct io_sq_data *sqd) __releases(&sqd->lock) { - WARN_ON_ONCE(sqd->thread == current); + WARN_ON_ONCE(sqpoll_task_locked(sqd) == current); /* * Do the dance but not conditional clear_bit() because it'd race with @@ -45,24 +45,32 @@ void io_sq_thread_unpark(struct io_sq_data *sqd) void io_sq_thread_park(struct io_sq_data *sqd) __acquires(&sqd->lock) { - WARN_ON_ONCE(data_race(sqd->thread) == current); + struct task_struct *tsk; atomic_inc(&sqd->park_pending); set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state); mutex_lock(&sqd->lock); - if (sqd->thread) - wake_up_process(sqd->thread); + + tsk = sqpoll_task_locked(sqd); + if (tsk) { + WARN_ON_ONCE(tsk == current); + wake_up_process(tsk); + } } void io_sq_thread_stop(struct io_sq_data *sqd) { - WARN_ON_ONCE(sqd->thread == current); + struct task_struct *tsk; + WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state)); set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state); mutex_lock(&sqd->lock); - if (sqd->thread) - wake_up_process(sqd->thread); + tsk = sqpoll_task_locked(sqd); + if (tsk) { + WARN_ON_ONCE(tsk == current); + wake_up_process(tsk); + } mutex_unlock(&sqd->lock); wait_for_completion(&sqd->exited); } @@ -277,7 +285,8 @@ static int io_sq_thread(void *data) /* offload context creation failed, just exit */ if (!current->io_uring) { mutex_lock(&sqd->lock); - sqd->thread = NULL; + rcu_assign_pointer(sqd->thread, NULL); + put_task_struct(current); mutex_unlock(&sqd->lock); goto err_out; } @@ -386,7 +395,8 @@ static int io_sq_thread(void *data) io_sq_tw(&retry_list, UINT_MAX); io_uring_cancel_generic(true, sqd); - sqd->thread = NULL; + rcu_assign_pointer(sqd->thread, NULL); + put_task_struct(current); list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) atomic_or(IORING_SQ_NEED_WAKEUP, &ctx->rings->sq_flags); io_run_task_work(); @@ -416,7 +426,6 @@ void io_sqpoll_wait_sq(struct io_ring_ctx *ctx) __cold int io_sq_offload_create(struct io_ring_ctx *ctx, struct io_uring_params *p) { - struct task_struct *task_to_put = NULL; int ret; /* Retain compatibility with failing for an invalid attach attempt */ @@ -496,8 +505,11 @@ __cold int io_sq_offload_create(struct io_ring_ctx *ctx, goto err_sqpoll; } - sqd->thread = tsk; - task_to_put = get_task_struct(tsk); + mutex_lock(&sqd->lock); + rcu_assign_pointer(sqd->thread, tsk); + mutex_unlock(&sqd->lock); + + get_task_struct(tsk); ret = io_uring_alloc_task_context(tsk, ctx); wake_up_new_task(tsk); if (ret) @@ -507,16 +519,11 @@ __cold int io_sq_offload_create(struct io_ring_ctx *ctx, ret = -EINVAL; goto err; } - - if (task_to_put) - put_task_struct(task_to_put); return 0; err_sqpoll: complete(&ctx->sq_data->exited); err: io_sq_thread_finish(ctx); - if (task_to_put) - put_task_struct(task_to_put); return ret; } @@ -527,10 +534,13 @@ __cold int io_sqpoll_wq_cpu_affinity(struct io_ring_ctx *ctx, int ret = -EINVAL; if (sqd) { + struct task_struct *tsk; + io_sq_thread_park(sqd); /* Don't set affinity for a dying thread */ - if (sqd->thread) - ret = io_wq_cpu_affinity(sqd->thread->io_uring, mask); + tsk = sqpoll_task_locked(sqd); + if (tsk) + ret = io_wq_cpu_affinity(tsk->io_uring, mask); io_sq_thread_unpark(sqd); } diff --git a/io_uring/sqpoll.h b/io_uring/sqpoll.h index 4171666b1cf4..b83dcdec9765 100644 --- a/io_uring/sqpoll.h +++ b/io_uring/sqpoll.h @@ -8,7 +8,7 @@ struct io_sq_data { /* ctx's that are using this sqd */ struct list_head ctx_list; - struct task_struct *thread; + struct task_struct __rcu *thread; struct wait_queue_head wait; unsigned sq_thread_idle; @@ -29,3 +29,9 @@ void io_sq_thread_unpark(struct io_sq_data *sqd); void io_put_sq_data(struct io_sq_data *sqd); void io_sqpoll_wait_sq(struct io_ring_ctx *ctx); int io_sqpoll_wq_cpu_affinity(struct io_ring_ctx *ctx, cpumask_var_t mask); + +static inline struct task_struct *sqpoll_task_locked(struct io_sq_data *sqd) +{ + return rcu_dereference_protected(sqd->thread, + lockdep_is_held(&sqd->lock)); +} |