io_uring: wrap multi-req freeing in struct req_batch

This cleans up the code a bit, and it allows us to build on top of the
multi-req freeing.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 9b869fb6c6353dbe7658cc7af03f01777934bf0d..0d02987abf40d2212b2659a3416b6b575fa7a5f4 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1132,14 +1132,19 @@ fallback:
        return NULL;
 }
 
-static void io_free_req_many(struct io_ring_ctx *ctx, void **reqs, int *nr)
+struct req_batch {
+       void *reqs[IO_IOPOLL_BATCH];
+       int to_free;
+};
+
+static void io_free_req_many(struct io_ring_ctx *ctx, struct req_batch *rb)
 {
-       if (*nr) {
-               kmem_cache_free_bulk(req_cachep, *nr, reqs);
-               percpu_ref_put_many(&ctx->refs, *nr);
-               percpu_ref_put_many(&ctx->file_data->refs, *nr);
-               *nr = 0;
-       }
+       if (!rb->to_free)
+               return;
+       kmem_cache_free_bulk(req_cachep, rb->to_free, rb->reqs);
+       percpu_ref_put_many(&ctx->refs, rb->to_free);
+       percpu_ref_put_many(&ctx->file_data->refs, rb->to_free);
+       rb->to_free = 0;
 }
 
 static void __io_req_do_free(struct io_kiocb *req)
@@ -1371,7 +1376,7 @@ static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
        return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
 }
 
-static inline bool io_req_multi_free(struct io_kiocb *req)
+static inline bool io_req_multi_free(struct req_batch *rb, struct io_kiocb *req)
 {
        /*
         * If we're not using fixed files, we have to pair the completion part
@@ -1379,8 +1384,12 @@ static inline bool io_req_multi_free(struct io_kiocb *req)
         * free for fixed file and non-linked commands.
         */
        if (((req->flags & (REQ_F_FIXED_FILE|REQ_F_LINK)) == REQ_F_FIXED_FILE)
-           && !io_is_fallback_req(req) && !req->io)
+           && !io_is_fallback_req(req) && !req->io) {
+               rb->reqs[rb->to_free++] = req;
+               if (unlikely(rb->to_free == ARRAY_SIZE(rb->reqs)))
+                       io_free_req_many(req->ctx, rb);
                return true;
+       }
 
        return false;
 }
@@ -1391,11 +1400,10 @@ static inline bool io_req_multi_free(struct io_kiocb *req)
 static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
                               struct list_head *done)
 {
-       void *reqs[IO_IOPOLL_BATCH];
+       struct req_batch rb;
        struct io_kiocb *req;
-       int to_free;
 
-       to_free = 0;
+       rb.to_free = 0;
        while (!list_empty(done)) {
                req = list_first_entry(done, struct io_kiocb, list);
                list_del(&req->list);
@@ -1403,19 +1411,13 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
                io_cqring_fill_event(req, req->result);
                (*nr_events)++;
 
-               if (refcount_dec_and_test(&req->refs)) {
-                       if (io_req_multi_free(req)) {
-                               reqs[to_free++] = req;
-                               if (to_free == ARRAY_SIZE(reqs))
-                                       io_free_req_many(ctx, reqs, &to_free);
-                       } else {
-                               io_free_req(req);
-                       }
-               }
+               if (refcount_dec_and_test(&req->refs) &&
+                   !io_req_multi_free(&rb, req))
+                       io_free_req(req);
        }
 
        io_commit_cqring(ctx);
-       io_free_req_many(ctx, reqs, &to_free);
+       io_free_req_many(ctx, &rb);
 }
 
 static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
@@ -3221,30 +3223,25 @@ static void io_poll_complete_work(struct io_wq_work **workptr)
 
 static void __io_poll_flush(struct io_ring_ctx *ctx, struct llist_node *nodes)
 {
-       void *reqs[IO_IOPOLL_BATCH];
        struct io_kiocb *req, *tmp;
-       int to_free = 0;
+       struct req_batch rb;
 
+       rb.to_free = 0;
        spin_lock_irq(&ctx->completion_lock);
        llist_for_each_entry_safe(req, tmp, nodes, llist_node) {
                hash_del(&req->hash_node);
                io_poll_complete(req, req->result, 0);
 
-               if (refcount_dec_and_test(&req->refs)) {
-                       if (io_req_multi_free(req)) {
-                               reqs[to_free++] = req;
-                               if (to_free == ARRAY_SIZE(reqs))
-                                       io_free_req_many(ctx, reqs, &to_free);
-                       } else {
-                               req->flags |= REQ_F_COMP_LOCKED;
-                               io_free_req(req);
-                       }
+               if (refcount_dec_and_test(&req->refs) &&
+                   !io_req_multi_free(&rb, req)) {
+                       req->flags |= REQ_F_COMP_LOCKED;
+                       io_free_req(req);
                }
        }
        spin_unlock_irq(&ctx->completion_lock);
 
        io_cqring_ev_posted(ctx);
-       io_free_req_many(ctx, reqs, &to_free);
+       io_free_req_many(ctx, &rb);
 }
 
 static void io_poll_flush(struct io_wq_work **workptr)