io_uring: use inflight_entry list for iopoll'ing

req->inflight_entry is used to track requests that grabbed files_struct.
Let's share it with iopoll list, because the only iopoll'ed ops are
reads and writes, which don't need a file table.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index c8ebd22..8a89480 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -651,6 +651,10 @@ struct io_kiocb {
 
        struct list_head        link_list;
 
+       /*
+        * 1. used with ctx->iopoll_list with reads/writes
+        * 2. to track reqs with ->files (see io_op_def::file_table)
+        */
        struct list_head        inflight_entry;
 
        struct percpu_ref       *fixed_file_refs;
@@ -1943,8 +1947,8 @@ static void io_iopoll_queue(struct list_head *again)
        struct io_kiocb *req;
 
        do {
-               req = list_first_entry(again, struct io_kiocb, list);
-               list_del(&req->list);
+               req = list_first_entry(again, struct io_kiocb, inflight_entry);
+               list_del(&req->inflight_entry);
                if (!io_rw_reissue(req, -EAGAIN))
                        io_complete_rw_common(&req->rw.kiocb, -EAGAIN, NULL);
        } while (!list_empty(again));
@@ -1967,13 +1971,13 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
        while (!list_empty(done)) {
                int cflags = 0;
 
-               req = list_first_entry(done, struct io_kiocb, list);
+               req = list_first_entry(done, struct io_kiocb, inflight_entry);
                if (READ_ONCE(req->result) == -EAGAIN) {
                        req->iopoll_completed = 0;
-                       list_move_tail(&req->list, &again);
+                       list_move_tail(&req->inflight_entry, &again);
                        continue;
                }
-               list_del(&req->list);
+               list_del(&req->inflight_entry);
 
                if (req->flags & REQ_F_BUFFER_SELECTED)
                        cflags = io_put_kbuf(req);
@@ -2009,7 +2013,7 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
        spin = !ctx->poll_multi_file && *nr_events < min;
 
        ret = 0;
-       list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, list) {
+       list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
                struct kiocb *kiocb = &req->rw.kiocb;
 
                /*
@@ -2018,7 +2022,7 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
                 * and complete those lists first, if we have entries there.
                 */
                if (READ_ONCE(req->iopoll_completed)) {
-                       list_move_tail(&req->list, &done);
+                       list_move_tail(&req->inflight_entry, &done);
                        continue;
                }
                if (!list_empty(&done))
@@ -2030,7 +2034,7 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
 
                /* iopoll may have completed current req */
                if (READ_ONCE(req->iopoll_completed))
-                       list_move_tail(&req->list, &done);
+                       list_move_tail(&req->inflight_entry, &done);
 
                if (ret && spin)
                        spin = false;
@@ -2297,7 +2301,7 @@ static void io_iopoll_req_issued(struct io_kiocb *req)
                struct io_kiocb *list_req;
 
                list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
-                                               list);
+                                               inflight_entry);
                if (list_req->file != req->file)
                        ctx->poll_multi_file = true;
        }
@@ -2307,9 +2311,9 @@ static void io_iopoll_req_issued(struct io_kiocb *req)
         * it to the front so we find it first.
         */
        if (READ_ONCE(req->iopoll_completed))
-               list_add(&req->list, &ctx->iopoll_list);
+               list_add(&req->inflight_entry, &ctx->iopoll_list);
        else
-               list_add_tail(&req->list, &ctx->iopoll_list);
+               list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
 
        if ((ctx->flags & IORING_SETUP_SQPOLL) &&
            wq_has_sleeper(&ctx->sqo_wait))