As every iopoll request have a task ref, it becomes expensive to put them one by one, instead we can put several at once integrating that into io_req_free_batch().
Signed-off-by: Pavel Begunkov <[email protected]> --- fs/io_uring.c | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 57e1f26b6a6b..b52aa0d8b09d 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1543,7 +1543,6 @@ static void io_dismantle_req(struct io_kiocb *req) kfree(req->io); if (req->file) io_put_file(req, req->file, (req->flags & REQ_F_FIXED_FILE)); - __io_put_req_task(req); io_req_clean_work(req); if (req->flags & REQ_F_INFLIGHT) { @@ -1563,6 +1562,7 @@ static void __io_free_req(struct io_kiocb *req) struct io_ring_ctx *ctx; io_dismantle_req(req); + __io_put_req_task(req); ctx = req->ctx; if (likely(!io_is_fallback_req(req))) kmem_cache_free(req_cachep, req); @@ -1806,8 +1806,18 @@ static void io_free_req(struct io_kiocb *req) struct req_batch { void *reqs[IO_IOPOLL_BATCH]; int to_free; + + struct task_struct *task; + int task_refs; }; +static inline void io_init_req_batch(struct req_batch *rb) +{ + rb->to_free = 0; + rb->task_refs = 0; + rb->task = NULL; +} + static void __io_req_free_batch_flush(struct io_ring_ctx *ctx, struct req_batch *rb) { @@ -1821,6 +1831,10 @@ static void io_req_free_batch_finish(struct io_ring_ctx *ctx, { if (rb->to_free) __io_req_free_batch_flush(ctx, rb); + if (rb->task) { + put_task_struct_many(rb->task, rb->task_refs); + rb->task = NULL; + } } static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req) @@ -1832,6 +1846,16 @@ static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req) if (req->flags & REQ_F_LINK_HEAD) io_queue_next(req); + if (req->flags & REQ_F_TASK_PINNED) { + if (req->task != rb->task && rb->task) { + put_task_struct_many(rb->task, rb->task_refs); + rb->task = req->task; + rb->task_refs = 0; + } + rb->task_refs++; + req->flags &= ~REQ_F_TASK_PINNED; + } + io_dismantle_req(req); rb->reqs[rb->to_free++] = req; if (unlikely(rb->to_free == ARRAY_SIZE(rb->reqs))) @@ -1977,7 +2001,7 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events, /* order with ->result store in io_complete_rw_iopoll() */ smp_rmb(); - rb.to_free = 0; + io_init_req_batch(&rb); while (!list_empty(done)) { int cflags = 0; -- 2.24.0
