ctx is always locked for task_work now, so get rid of struct
io_tw_state::locked. Note I'm stopping one step before removing
io_tw_state altogether, which is not empty, because it still serves the
purpose of indicating which function is a tw callback and forcing users
not to invoke them carelessly out of a wrong context. The removal can
always be done later.
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
include/linux/io_uring_types.h | 2 --
io_uring/io_uring.c | 31 ++++++++-----------------------
io_uring/io_uring.h | 5 +----
io_uring/poll.c | 2 +-
io_uring/rw.c | 6 ++----
io_uring/timeout.c | 8 ++------
io_uring/uring_cmd.c | 8 ++------
io_uring/waitid.c | 2 +-
8 files changed, 17 insertions(+), 47 deletions(-)
diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
index e24893625085..5a2afbc93887 100644
--- a/include/linux/io_uring_types.h
+++ b/include/linux/io_uring_types.h
@@ -439,8 +439,6 @@ struct io_ring_ctx {
};
struct io_tw_state {
- /* ->uring_lock is taken, callbacks can use io_tw_lock to lock it */
- bool locked;
};
enum {
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 66669cc9a675..9e8afc006fc9 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -246,14 +246,12 @@ static __cold void io_fallback_req_func(struct work_struct *work)
fallback_work.work);
struct llist_node *node = llist_del_all(&ctx->fallback_llist);
struct io_kiocb *req, *tmp;
- struct io_tw_state ts = { .locked = true, };
+ struct io_tw_state ts = {};
percpu_ref_get(&ctx->refs);
mutex_lock(&ctx->uring_lock);
llist_for_each_entry_safe(req, tmp, node, io_task_work.node)
req->io_task_work.func(req, &ts);
- if (WARN_ON_ONCE(!ts.locked))
- return;
io_submit_flush_completions(ctx);
mutex_unlock(&ctx->uring_lock);
percpu_ref_put(&ctx->refs);
@@ -1157,11 +1155,9 @@ static void ctx_flush_and_put(struct io_ring_ctx *ctx, struct io_tw_state *ts)
return;
if (ctx->flags & IORING_SETUP_TASKRUN_FLAG)
atomic_andnot(IORING_SQ_TASKRUN, &ctx->rings->sq_flags);
- if (ts->locked) {
- io_submit_flush_completions(ctx);
- mutex_unlock(&ctx->uring_lock);
- ts->locked = false;
- }
+
+ io_submit_flush_completions(ctx);
+ mutex_unlock(&ctx->uring_lock);
percpu_ref_put(&ctx->refs);
}
@@ -1185,8 +1181,6 @@ struct llist_node *io_handle_tw_list(struct llist_node *node,
if (req->ctx != ctx) {
ctx_flush_and_put(ctx, &ts);
ctx = req->ctx;
-
- ts.locked = true;
mutex_lock(&ctx->uring_lock);
percpu_ref_get(&ctx->refs);
}
@@ -1459,22 +1453,16 @@ static int __io_run_local_work(struct io_ring_ctx *ctx, struct io_tw_state *ts,
static inline int io_run_local_work_locked(struct io_ring_ctx *ctx,
int min_events)
{
- struct io_tw_state ts = { .locked = true, };
- int ret;
+ struct io_tw_state ts = {};
if (llist_empty(&ctx->work_llist))
return 0;
-
- ret = __io_run_local_work(ctx, &ts, min_events);
- /* shouldn't happen! */
- if (WARN_ON_ONCE(!ts.locked))
- mutex_lock(&ctx->uring_lock);
- return ret;
+ return __io_run_local_work(ctx, &ts, min_events);
}
static int io_run_local_work(struct io_ring_ctx *ctx, int min_events)
{
- struct io_tw_state ts = { .locked = true };
+ struct io_tw_state ts = {};
int ret;
mutex_lock(&ctx->uring_lock);
@@ -1702,10 +1690,7 @@ static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
void io_req_task_complete(struct io_kiocb *req, struct io_tw_state *ts)
{
- if (ts->locked)
- io_req_complete_defer(req);
- else
- io_req_complete_post(req, IO_URING_F_UNLOCKED);
+ io_req_complete_defer(req);
}
/*
diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h
index 0861d49e83de..7f921daae9c3 100644
--- a/io_uring/io_uring.h
+++ b/io_uring/io_uring.h
@@ -351,10 +351,7 @@ static inline bool io_task_work_pending(struct io_ring_ctx *ctx)
static inline void io_tw_lock(struct io_ring_ctx *ctx, struct io_tw_state *ts)
{
- if (!ts->locked) {
- mutex_lock(&ctx->uring_lock);
- ts->locked = true;
- }
+ lockdep_assert_held(&ctx->uring_lock);
}
/*
diff --git a/io_uring/poll.c b/io_uring/poll.c
index 6db1dcb2c797..8901dd118e50 100644
--- a/io_uring/poll.c
+++ b/io_uring/poll.c
@@ -322,7 +322,7 @@ static int io_poll_check_events(struct io_kiocb *req, struct io_tw_state *ts)
__poll_t mask = mangle_poll(req->cqe.res &
req->apoll_events);
- if (!io_fill_cqe_req_aux(req, ts->locked, mask,
+ if (!io_fill_cqe_req_aux(req, true, mask,
IORING_CQE_F_MORE)) {
io_req_set_res(req, mask, 0);
return IOU_POLL_REMOVE_POLL_USE_RES;
diff --git a/io_uring/rw.c b/io_uring/rw.c
index 576934dbf833..c7f9246ff508 100644
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -305,11 +305,9 @@ void io_req_rw_complete(struct io_kiocb *req, struct io_tw_state *ts)
io_req_io_end(req);
- if (req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING)) {
- unsigned issue_flags = ts->locked ? 0 : IO_URING_F_UNLOCKED;
+ if (req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING))
+ req->cqe.flags |= io_put_kbuf(req, 0);
- req->cqe.flags |= io_put_kbuf(req, issue_flags);
- }
io_req_task_complete(req, ts);
}
diff --git a/io_uring/timeout.c b/io_uring/timeout.c
index 7fd7dbb211d6..0a48e6acd0b2 100644
--- a/io_uring/timeout.c
+++ b/io_uring/timeout.c
@@ -72,10 +72,7 @@ static void io_timeout_complete(struct io_kiocb *req, struct io_tw_state *ts)
struct io_ring_ctx *ctx = req->ctx;
if (!io_timeout_finish(timeout, data)) {
- bool filled;
- filled = io_fill_cqe_req_aux(req, ts->locked, -ETIME,
- IORING_CQE_F_MORE);
- if (filled) {
+ if (io_fill_cqe_req_aux(req, true, -ETIME, IORING_CQE_F_MORE)) {
/* re-arm timer */
spin_lock_irq(&ctx->timeout_lock);
list_add(&timeout->list, ctx->timeout_list.prev);
@@ -301,7 +298,6 @@ int io_timeout_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd)
static void io_req_task_link_timeout(struct io_kiocb *req, struct io_tw_state *ts)
{
- unsigned issue_flags = ts->locked ? 0 : IO_URING_F_UNLOCKED;
struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
struct io_kiocb *prev = timeout->prev;
int ret = -ENOENT;
@@ -313,7 +309,7 @@ static void io_req_task_link_timeout(struct io_kiocb *req, struct io_tw_state *t
.data = prev->cqe.user_data,
};
- ret = io_try_cancel(req->task->io_uring, &cd, issue_flags);
+ ret = io_try_cancel(req->task->io_uring, &cd, 0);
}
io_req_set_res(req, ret ?: -ETIME, 0);
io_req_task_complete(req, ts);
diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c
index 759f919b14a9..4614ce734fee 100644
--- a/io_uring/uring_cmd.c
+++ b/io_uring/uring_cmd.c
@@ -87,13 +87,9 @@ EXPORT_SYMBOL_GPL(io_uring_cmd_mark_cancelable);
static void io_uring_cmd_work(struct io_kiocb *req, struct io_tw_state *ts)
{
struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
- unsigned issue_flags = IO_URING_F_UNLOCKED;
- /* locked task_work executor checks the deffered list completion */
- if (ts->locked)
- issue_flags = IO_URING_F_COMPLETE_DEFER;
-
- ioucmd->task_work_cb(ioucmd, issue_flags);
+ /* task_work executor checks the deffered list completion */
+ ioucmd->task_work_cb(ioucmd, IO_URING_F_COMPLETE_DEFER);
}
void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
diff --git a/io_uring/waitid.c b/io_uring/waitid.c
index 77d340666cb9..6362ec20abc0 100644
--- a/io_uring/waitid.c
+++ b/io_uring/waitid.c
@@ -118,7 +118,7 @@ static int io_waitid_finish(struct io_kiocb *req, int ret)
static void io_waitid_complete(struct io_kiocb *req, int ret)
{
struct io_waitid *iw = io_kiocb_to_cmd(req, struct io_waitid);
- struct io_tw_state ts = { .locked = true };
+ struct io_tw_state ts = {};
/* anyone completing better be holding a reference */
WARN_ON_ONCE(!(atomic_read(&iw->refs) & IO_WAITID_REF_MASK));
--
2.44.0
