Rather than store the task_struct itself in struct io_kiocb, store
the io_uring specific task_struct. The life times are the same in terms
of io_uring, and this avoids doing some dereferences through the
task_struct. For the hot path of putting local task references, we can
deref req->tctx instead, which we'll need anyway in that function
regardless of whether it's local or remote references.
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
include/linux/io_uring/cmd.h | 2 +-
include/linux/io_uring_types.h | 3 ++-
io_uring/cancel.c | 2 +-
io_uring/fdinfo.c | 2 +-
io_uring/io_uring.c | 34 +++++++++++++++-------------------
io_uring/msg_ring.c | 4 ++--
io_uring/notif.c | 4 ++--
io_uring/poll.c | 3 +--
io_uring/rw.c | 2 +-
io_uring/tctx.c | 1 +
io_uring/timeout.c | 6 +++---
io_uring/uring_cmd.c | 2 +-
io_uring/waitid.c | 2 +-
13 files changed, 32 insertions(+), 35 deletions(-)
diff --git a/include/linux/io_uring/cmd.h b/include/linux/io_uring/cmd.h
index c189d36ad55e..578a3fdf5c71 100644
--- a/include/linux/io_uring/cmd.h
+++ b/include/linux/io_uring/cmd.h
@@ -110,7 +110,7 @@ static inline void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
static inline struct task_struct *io_uring_cmd_get_task(struct io_uring_cmd *cmd)
{
- return cmd_to_io_kiocb(cmd)->task;
+ return cmd_to_io_kiocb(cmd)->tctx->task;
}
#endif /* _LINUX_IO_URING_CMD_H */
diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
index a87927a392f2..ad5001102c86 100644
--- a/include/linux/io_uring_types.h
+++ b/include/linux/io_uring_types.h
@@ -84,6 +84,7 @@ struct io_uring_task {
/* submission side */
int cached_refs;
const struct io_ring_ctx *last;
+ struct task_struct *task;
struct io_wq *io_wq;
struct file *registered_rings[IO_RINGFD_REG_MAX];
@@ -633,7 +634,7 @@ struct io_kiocb {
struct io_cqe cqe;
struct io_ring_ctx *ctx;
- struct task_struct *task;
+ struct io_uring_task *tctx;
union {
/* stores selected buf, valid IFF REQ_F_BUFFER_SELECTED is set */
diff --git a/io_uring/cancel.c b/io_uring/cancel.c
index bbca5cb69cb5..484193567839 100644
--- a/io_uring/cancel.c
+++ b/io_uring/cancel.c
@@ -205,7 +205,7 @@ int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
.opcode = cancel->opcode,
.seq = atomic_inc_return(&req->ctx->cancel_seq),
};
- struct io_uring_task *tctx = req->task->io_uring;
+ struct io_uring_task *tctx = req->tctx;
int ret;
if (cd.flags & IORING_ASYNC_CANCEL_FD) {
diff --git a/io_uring/fdinfo.c b/io_uring/fdinfo.c
index 8da0d9e4533a..efbec34ccb18 100644
--- a/io_uring/fdinfo.c
+++ b/io_uring/fdinfo.c
@@ -203,7 +203,7 @@ __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *file)
hlist_for_each_entry(req, &hb->list, hash_node)
seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
- task_work_pending(req->task));
+ task_work_pending(req->tctx->task));
}
if (has_lock)
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 496f61de0f9b..d9a6a8703563 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -207,7 +207,7 @@ bool io_match_task_safe(struct io_kiocb *head, struct io_uring_task *tctx,
{
bool matched;
- if (tctx && head->task->io_uring != tctx)
+ if (tctx && head->tctx != tctx)
return false;
if (cancel_all)
return true;
@@ -408,11 +408,8 @@ static void io_clean_op(struct io_kiocb *req)
kfree(req->apoll);
req->apoll = NULL;
}
- if (req->flags & REQ_F_INFLIGHT) {
- struct io_uring_task *tctx = req->task->io_uring;
-
- atomic_dec(&tctx->inflight_tracked);
- }
+ if (req->flags & REQ_F_INFLIGHT)
+ atomic_dec(&req->tctx->inflight_tracked);
if (req->flags & REQ_F_CREDS)
put_cred(req->creds);
if (req->flags & REQ_F_ASYNC_DATA) {
@@ -426,7 +423,7 @@ static inline void io_req_track_inflight(struct io_kiocb *req)
{
if (!(req->flags & REQ_F_INFLIGHT)) {
req->flags |= REQ_F_INFLIGHT;
- atomic_inc(&req->task->io_uring->inflight_tracked);
+ atomic_inc(&req->tctx->inflight_tracked);
}
}
@@ -515,7 +512,7 @@ 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;
+ struct io_uring_task *tctx = req->tctx;
BUG_ON(!tctx);
BUG_ON(!tctx->io_wq);
@@ -530,7 +527,7 @@ static void io_queue_iowq(struct io_kiocb *req)
* procedure rather than attempt to run this request (or create a new
* worker for it).
*/
- if (WARN_ON_ONCE(!same_thread_group(req->task, current)))
+ if (WARN_ON_ONCE(!same_thread_group(tctx->task, current)))
atomic_or(IO_WQ_WORK_CANCEL, &req->work.flags);
trace_io_uring_queue_async_work(req, io_wq_is_hashed(&req->work));
@@ -679,17 +676,17 @@ static void io_cqring_do_overflow_flush(struct io_ring_ctx *ctx)
}
/* must to be called somewhat shortly after putting a request */
-static inline void io_put_task(struct task_struct *task)
+static inline void io_put_task(struct io_kiocb *req)
{
- struct io_uring_task *tctx = task->io_uring;
+ struct io_uring_task *tctx = req->tctx;
- if (likely(task == current)) {
+ if (likely(tctx->task == current)) {
tctx->cached_refs++;
} else {
percpu_counter_sub(&tctx->inflight, 1);
if (unlikely(atomic_read(&tctx->in_cancel)))
wake_up(&tctx->wait);
- put_task_struct(task);
+ put_task_struct(tctx->task);
}
}
@@ -1340,7 +1337,7 @@ static inline void io_req_local_work_add(struct io_kiocb *req,
static void io_req_normal_work_add(struct io_kiocb *req)
{
- struct io_uring_task *tctx = req->task->io_uring;
+ struct io_uring_task *tctx = req->tctx;
struct io_ring_ctx *ctx = req->ctx;
/* task_work already pending, we're done */
@@ -1359,7 +1356,7 @@ static void io_req_normal_work_add(struct io_kiocb *req)
return;
}
- if (likely(!task_work_add(req->task, &tctx->task_work, ctx->notify_method)))
+ if (likely(!task_work_add(tctx->task, &tctx->task_work, ctx->notify_method)))
return;
io_fallback_tw(tctx, false);
@@ -1476,8 +1473,7 @@ static void io_req_task_cancel(struct io_kiocb *req, struct io_tw_state *ts)
void io_req_task_submit(struct io_kiocb *req, struct io_tw_state *ts)
{
io_tw_lock(req->ctx, ts);
- /* req->task == current here, checking PF_EXITING is safe */
- if (unlikely(req->task->flags & PF_EXITING))
+ if (unlikely(current->flags & PF_EXITING))
io_req_defer_failed(req, -EFAULT);
else if (req->flags & REQ_F_FORCE_ASYNC)
io_queue_iowq(req);
@@ -1561,7 +1557,7 @@ static void io_free_batch_list(struct io_ring_ctx *ctx,
}
io_put_file(req);
io_req_put_rsrc_nodes(req);
- io_put_task(req->task);
+ io_put_task(req);
node = req->comp_list.next;
io_req_add_to_cache(req, ctx);
@@ -2181,7 +2177,7 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
req->flags = (__force io_req_flags_t) sqe_flags;
req->cqe.user_data = READ_ONCE(sqe->user_data);
req->file = NULL;
- req->task = current;
+ req->tctx = current->io_uring;
req->cancel_seq_set = false;
if (unlikely(opcode >= IORING_OP_LAST)) {
diff --git a/io_uring/msg_ring.c b/io_uring/msg_ring.c
index 99af39e1d0fb..e63af34004b7 100644
--- a/io_uring/msg_ring.c
+++ b/io_uring/msg_ring.c
@@ -89,8 +89,8 @@ static void io_msg_tw_complete(struct io_kiocb *req, struct io_tw_state *ts)
static int io_msg_remote_post(struct io_ring_ctx *ctx, struct io_kiocb *req,
int res, u32 cflags, u64 user_data)
{
- req->task = READ_ONCE(ctx->submitter_task);
- if (!req->task) {
+ req->tctx = READ_ONCE(ctx->submitter_task->io_uring);
+ if (!req->tctx) {
kmem_cache_free(req_cachep, req);
return -EOWNERDEAD;
}
diff --git a/io_uring/notif.c b/io_uring/notif.c
index 8dfbb0bd8e4d..ee3a33510b3c 100644
--- a/io_uring/notif.c
+++ b/io_uring/notif.c
@@ -89,7 +89,7 @@ static int io_link_skb(struct sk_buff *skb, struct ubuf_info *uarg)
/* make sure all noifications can be finished in the same task_work */
if (unlikely(notif->ctx != prev_notif->ctx ||
- notif->task != prev_notif->task))
+ notif->tctx != prev_notif->tctx))
return -EEXIST;
nd->head = prev_nd->head;
@@ -115,7 +115,7 @@ struct io_kiocb *io_alloc_notif(struct io_ring_ctx *ctx)
notif->opcode = IORING_OP_NOP;
notif->flags = 0;
notif->file = NULL;
- notif->task = current;
+ notif->tctx = current->io_uring;
io_get_task_refs(1);
notif->file_node = NULL;
notif->buf_node = NULL;
diff --git a/io_uring/poll.c b/io_uring/poll.c
index 7db3010b5733..56332893a4b0 100644
--- a/io_uring/poll.c
+++ b/io_uring/poll.c
@@ -224,8 +224,7 @@ static int io_poll_check_events(struct io_kiocb *req, struct io_tw_state *ts)
{
int v;
- /* req->task == current here, checking PF_EXITING is safe */
- if (unlikely(req->task->flags & PF_EXITING))
+ if (unlikely(current->flags & PF_EXITING))
return -ECANCELED;
do {
diff --git a/io_uring/rw.c b/io_uring/rw.c
index 144730344c0f..e368b9afde03 100644
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -435,7 +435,7 @@ static bool io_rw_should_reissue(struct io_kiocb *req)
* Play it safe and assume not safe to re-import and reissue if we're
* not in the original thread group (or in task context).
*/
- if (!same_thread_group(req->task, current) || !in_task())
+ if (!same_thread_group(req->tctx->task, current) || !in_task())
return false;
return true;
}
diff --git a/io_uring/tctx.c b/io_uring/tctx.c
index c043fe93a3f2..503f3ff8bc4f 100644
--- a/io_uring/tctx.c
+++ b/io_uring/tctx.c
@@ -81,6 +81,7 @@ __cold int io_uring_alloc_task_context(struct task_struct *task,
return ret;
}
+ tctx->task = task;
xa_init(&tctx->xa);
init_waitqueue_head(&tctx->wait);
atomic_set(&tctx->in_cancel, 0);
diff --git a/io_uring/timeout.c b/io_uring/timeout.c
index 31fbea366d43..fd1f58f68fa1 100644
--- a/io_uring/timeout.c
+++ b/io_uring/timeout.c
@@ -305,13 +305,13 @@ static void io_req_task_link_timeout(struct io_kiocb *req, struct io_tw_state *t
int ret = -ENOENT;
if (prev) {
- if (!(req->task->flags & PF_EXITING)) {
+ if (!(current->flags & PF_EXITING)) {
struct io_cancel_data cd = {
.ctx = req->ctx,
.data = prev->cqe.user_data,
};
- ret = io_try_cancel(req->task->io_uring, &cd, 0);
+ ret = io_try_cancel(req->tctx, &cd, 0);
}
io_req_set_res(req, ret ?: -ETIME, 0);
io_req_task_complete(req, ts);
@@ -649,7 +649,7 @@ static bool io_match_task(struct io_kiocb *head, struct io_uring_task *tctx,
{
struct io_kiocb *req;
- if (tctx && head->task->io_uring != tctx)
+ if (tctx && head->tctx != tctx)
return false;
if (cancel_all)
return true;
diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c
index f88fbc9869d0..40b8b777ba12 100644
--- a/io_uring/uring_cmd.c
+++ b/io_uring/uring_cmd.c
@@ -61,7 +61,7 @@ bool io_uring_try_cancel_uring_cmd(struct io_ring_ctx *ctx,
struct io_uring_cmd);
struct file *file = req->file;
- if (!cancel_all && req->task->io_uring != tctx)
+ if (!cancel_all && req->tctx != tctx)
continue;
if (cmd->flags & IORING_URING_CMD_CANCELABLE) {
diff --git a/io_uring/waitid.c b/io_uring/waitid.c
index 9b7c23f96c47..daef5dd644f0 100644
--- a/io_uring/waitid.c
+++ b/io_uring/waitid.c
@@ -331,7 +331,7 @@ int io_waitid(struct io_kiocb *req, unsigned int issue_flags)
hlist_add_head(&req->hash_node, &ctx->waitid_list);
init_waitqueue_func_entry(&iwa->wo.child_wait, io_waitid_wait);
- iwa->wo.child_wait.private = req->task;
+ iwa->wo.child_wait.private = req->tctx->task;
iw->head = ¤t->signal->wait_chldexit;
add_wait_queue(iw->head, &iwa->wo.child_wait);
--
2.45.2
