From d886e185a128a4f350c4df6471c0f403c2982ae8 Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <asml.silence@gmail.com>
Date: Mon, 4 Oct 2021 20:02:56 +0100
Subject: [PATCH] io_uring: control ->async_data with a REQ_F flag
Git-commit: d886e185a128a4f350c4df6471c0f403c2982ae8
Patch-mainline: v5.16-rc1
References: bsc#1205205
->async_data is a slow path, so it won't matter much if we do the clean
up inside io_clean_op(). Moreover, in many cases it's allocated together
with setting one or more of IO_REQ_CLEAN_FLAGS flags, so it'd go through
io_clean_op() anyway.
Control ->async_data allocation with a new flag REQ_F_ASYNC_DATA, so we
can do all the maintainence under io_req_needs_clean() fast check.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6892cf5883c459f36bda26f30ceb16742b20b84b.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
---
fs/io_uring.c | 72 ++++++++++++++++++++++++++++++++-------------------
1 file changed, 46 insertions(+), 26 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 1b007f77fe52..aee8ecc09168 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -109,7 +109,8 @@
#define SQE_VALID_FLAGS (SQE_COMMON_FLAGS|IOSQE_BUFFER_SELECT|IOSQE_IO_DRAIN)
#define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \
- REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS)
+ REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS | \
+ REQ_F_ASYNC_DATA)
#define IO_TCTX_REFS_CACHE_NR (1U << 10)
@@ -732,6 +733,7 @@ enum {
REQ_F_CREDS_BIT,
REQ_F_REFCOUNT_BIT,
REQ_F_ARM_LTIMEOUT_BIT,
+ REQ_F_ASYNC_DATA_BIT,
/* keep async read/write and isreg together and in order */
REQ_F_NOWAIT_READ_BIT,
REQ_F_NOWAIT_WRITE_BIT,
@@ -787,6 +789,8 @@ enum {
REQ_F_REFCOUNT = BIT(REQ_F_REFCOUNT_BIT),
/* there is a linked timeout that has to be armed */
REQ_F_ARM_LTIMEOUT = BIT(REQ_F_ARM_LTIMEOUT_BIT),
+ /* ->async_data allocated */
+ REQ_F_ASYNC_DATA = BIT(REQ_F_ASYNC_DATA_BIT),
};
struct async_poll {
@@ -847,8 +851,6 @@ struct io_kiocb {
struct io_completion compl;
};
- /* opcode allocated if it needs to store data for async defer */
- void *async_data;
u8 opcode;
/* polled IO has completed */
u8 iopoll_completed;
@@ -863,6 +865,8 @@ struct io_kiocb {
u64 user_data;
struct percpu_ref *fixed_rsrc_refs;
+ /* store used ubuf, so we can prevent reloading */
+ struct io_mapped_ubuf *imu;
/* used by request caches, completion batching and iopoll */
struct io_wq_work_node comp_list;
@@ -872,8 +876,9 @@ struct io_kiocb {
struct hlist_node hash_node;
/* internal polling, see IORING_FEAT_FAST_POLL */
struct async_poll *apoll;
- /* store used ubuf, so we can prevent reloading */
- struct io_mapped_ubuf *imu;
+
+ /* opcode allocated if it needs to store data for async defer */
+ void *async_data;
struct io_wq_work work;
/* custom credentials, valid IFF REQ_F_CREDS is set */
const struct cred *creds;
@@ -1219,6 +1224,11 @@ static bool io_match_task(struct io_kiocb *head, struct task_struct *task,
return false;
}
+static inline bool req_has_async_data(struct io_kiocb *req)
+{
+ return req->flags & REQ_F_ASYNC_DATA;
+}
+
static inline void req_set_fail(struct io_kiocb *req)
{
req->flags |= REQ_F_FAIL;
@@ -1969,10 +1979,6 @@ static inline void io_dismantle_req(struct io_kiocb *req)
io_put_file(req->file);
if (req->fixed_rsrc_refs)
percpu_ref_put(req->fixed_rsrc_refs);
- if (req->async_data) {
- kfree(req->async_data);
- req->async_data = NULL;
- }
}
static __cold void __io_free_req(struct io_kiocb *req)
@@ -2566,7 +2572,7 @@ static bool io_resubmit_prep(struct io_kiocb *req)
{
struct io_async_rw *rw = req->async_data;
- if (!rw)
+ if (!req_has_async_data(req))
return !io_req_prep_async(req);
iov_iter_restore(&rw->iter, &rw->iter_state);
return true;
@@ -2878,7 +2884,7 @@ static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
struct io_async_rw *io = req->async_data;
/* add previously done IO, if any */
- if (io && io->bytes_done > 0) {
+ if (req_has_async_data(req) && io->bytes_done > 0) {
if (ret < 0)
ret = io->bytes_done;
else
@@ -3257,7 +3263,11 @@ static inline bool io_alloc_async_data(struct io_kiocb *req)
{
WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
- return req->async_data == NULL;
+ if (req->async_data) {
+ req->flags |= REQ_F_ASYNC_DATA;
+ return false;
+ }
+ return true;
}
static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
@@ -3266,7 +3276,7 @@ static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
{
if (!force && !io_op_defs[req->opcode].needs_async_setup)
return 0;
- if (!req->async_data) {
+ if (!req_has_async_data(req)) {
struct io_async_rw *iorw;
if (io_alloc_async_data(req)) {
@@ -3399,12 +3409,13 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
struct kiocb *kiocb = &req->rw.kiocb;
struct iov_iter __iter, *iter = &__iter;
- struct io_async_rw *rw = req->async_data;
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
struct iov_iter_state __state, *state;
+ struct io_async_rw *rw;
ssize_t ret, ret2;
- if (rw) {
+ if (req_has_async_data(req)) {
+ rw = req->async_data;
iter = &rw->iter;
state = &rw->iter_state;
/*
@@ -3534,12 +3545,13 @@ static int io_write(struct io_kiocb *req, unsigned int issue_flags)
struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
struct kiocb *kiocb = &req->rw.kiocb;
struct iov_iter __iter, *iter = &__iter;
- struct io_async_rw *rw = req->async_data;
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
struct iov_iter_state __state, *state;
+ struct io_async_rw *rw;
ssize_t ret, ret2;
- if (rw) {
+ if (req_has_async_data(req)) {
+ rw = req->async_data;
iter = &rw->iter;
state = &rw->iter_state;
iov_iter_restore(iter, state);
@@ -4708,8 +4720,9 @@ static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
if (unlikely(!sock))
return -ENOTSOCK;
- kmsg = req->async_data;
- if (!kmsg) {
+ if (req_has_async_data(req)) {
+ kmsg = req->async_data;
+ } else {
ret = io_sendmsg_copy_hdr(req, &iomsg);
if (ret)
return ret;
@@ -4925,8 +4938,9 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
if (unlikely(!sock))
return -ENOTSOCK;
- kmsg = req->async_data;
- if (!kmsg) {
+ if (req_has_async_data(req)) {
+ kmsg = req->async_data;
+ } else {
ret = io_recvmsg_copy_hdr(req, &iomsg);
if (ret)
return ret;
@@ -5117,7 +5131,7 @@ static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
int ret;
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
- if (req->async_data) {
+ if (req_has_async_data(req)) {
io = req->async_data;
} else {
ret = move_addr_to_kernel(req->connect.addr,
@@ -5133,7 +5147,7 @@ static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
ret = __sys_connect_file(req->file, &io->address,
req->connect.addr_len, file_flags);
if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
- if (req->async_data)
+ if (req_has_async_data(req))
return -EAGAIN;
if (io_alloc_async_data(req)) {
ret = -ENOMEM;
@@ -5424,7 +5438,10 @@ static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake);
req_ref_get(req);
poll->wait.private = req;
+
*poll_ptr = poll;
+ if (req->opcode == IORING_OP_POLL_ADD)
+ req->flags |= REQ_F_ASYNC_DATA;
}
pt->nr_entries++;
@@ -6086,7 +6103,7 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
if (unlikely(off && !req->ctx->off_timeout_used))
req->ctx->off_timeout_used = true;
- if (!req->async_data && io_alloc_async_data(req))
+ if (!req_has_async_data(req) && io_alloc_async_data(req))
return -ENOMEM;
data = req->async_data;
@@ -6395,7 +6412,7 @@ static int io_req_prep_async(struct io_kiocb *req)
{
if (!io_op_defs[req->opcode].needs_async_setup)
return 0;
- if (WARN_ON_ONCE(req->async_data))
+ if (WARN_ON_ONCE(req_has_async_data(req)))
return -EFAULT;
if (io_alloc_async_data(req))
return -EAGAIN;
@@ -6538,7 +6555,10 @@ static void io_clean_op(struct io_kiocb *req)
}
if (req->flags & REQ_F_CREDS)
put_cred(req->creds);
-
+ if (req->flags & REQ_F_ASYNC_DATA) {
+ kfree(req->async_data);
+ req->async_data = NULL;
+ }
req->flags &= ~IO_REQ_CLEAN_FLAGS;
}
--
2.35.3