[RFC 1/2] io_uring: add tw add flags

Pavel Begunkov
2023-03-10T19:05:40Z

We pass 'allow_local' into io_req_task_work_add() but will need more
flags. Replace it with a flags bit field and name this allow_local
flag.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
io_uring/io_uring.c | 7 ++++---
io_uring/io_uring.h | 9 +++++++--
2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 7625597b5227..42ada470845f 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1308,12 +1308,13 @@ static void io_req_local_work_add(struct io_kiocb *req)
percpu_ref_put(&ctx->refs);
}

-void __io_req_task_work_add(struct io_kiocb *req, bool allow_local)
+void __io_req_task_work_add(struct io_kiocb *req, unsigned flags)
{
struct io_uring_task *tctx = req->task->io_uring;
struct io_ring_ctx *ctx = req->ctx;

- if (allow_local && ctx->flags & IORING_SETUP_DEFER_TASKRUN) {
+ if (!(flags & IOU_F_TWQ_FORCE_NORMAL) &&
+ (ctx->flags & IORING_SETUP_DEFER_TASKRUN)) {
io_req_local_work_add(req);
return;
}
@@ -1341,7 +1342,7 @@ static void __cold io_move_task_work_from_local(struct io_ring_ctx *ctx)
io_task_work.node);

node = node->next;
- __io_req_task_work_add(req, false);
+ __io_req_task_work_add(req, IOU_F_TWQ_FORCE_NORMAL);
}
}

diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h
index 2711865f1e19..cd2e702f206c 100644
--- a/io_uring/io_uring.h
+++ b/io_uring/io_uring.h
@@ -15,6 +15,11 @@
#include <trace/events/io_uring.h>
#endif

+enum {
+ /* don't use deferred task_work */
+ IOU_F_TWQ_FORCE_NORMAL = 1,
+};
+
enum {
IOU_OK = 0,
IOU_ISSUE_SKIP_COMPLETE = -EIOCBQUEUED,
@@ -48,7 +53,7 @@ static inline bool io_req_ffs_set(struct io_kiocb *req)
return req->flags & REQ_F_FIXED_FILE;
}

-void __io_req_task_work_add(struct io_kiocb *req, bool allow_local);
+void __io_req_task_work_add(struct io_kiocb *req, unsigned flags);
bool io_is_uring_fops(struct file *file);
bool io_alloc_async_data(struct io_kiocb *req);
void io_req_task_queue(struct io_kiocb *req);
@@ -93,7 +98,7 @@ bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,

static inline void io_req_task_work_add(struct io_kiocb *req)
{
- __io_req_task_work_add(req, true);
+ __io_req_task_work_add(req, 0);
}

#define io_for_each_link(pos, head) \
--
2.39.1