From 428f13826855e3eea44bf13cedbf33f382ef8794 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 14 Feb 2024 12:59:36 -0700 Subject: io_uring/napi: ensure napi polling is aborted when work is available While testing io_uring NAPI with DEFER_TASKRUN, I ran into slowdowns and stalls in packet delivery. Turns out that while io_napi_busy_loop_should_end() aborts appropriately on regular task_work, it does not abort if we have local task_work pending. Move io_has_work() into the private io_uring.h header, and gate whether we should continue polling on that as well. This makes NAPI polling on send/receive work as designed with IORING_SETUP_DEFER_TASKRUN as well. Fixes: 8d0c12a80cde ("io-uring: add napi busy poll support") Signed-off-by: Jens Axboe --- io_uring/io_uring.c | 11 ----------- io_uring/io_uring.h | 11 +++++++++++ io_uring/napi.c | 2 +- 3 files changed, 12 insertions(+), 12 deletions(-) (limited to 'io_uring') diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index b25c2217c3224..844a7524ed916 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -122,11 +122,6 @@ #define IO_COMPL_BATCH 32 #define IO_REQ_ALLOC_BATCH 8 -enum { - IO_CHECK_CQ_OVERFLOW_BIT, - IO_CHECK_CQ_DROPPED_BIT, -}; - struct io_defer_entry { struct list_head list; struct io_kiocb *req; @@ -2479,12 +2474,6 @@ int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) return ret; } -static inline bool io_has_work(struct io_ring_ctx *ctx) -{ - return test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq) || - !llist_empty(&ctx->work_llist); -} - static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode, int wake_flags, void *key) { diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h index 1ca99522811b4..6426ee382276b 100644 --- a/io_uring/io_uring.h +++ b/io_uring/io_uring.h @@ -448,4 +448,15 @@ static inline bool io_file_can_poll(struct io_kiocb *req) } return false; } + +enum { + IO_CHECK_CQ_OVERFLOW_BIT, + IO_CHECK_CQ_DROPPED_BIT, +}; + +static inline bool io_has_work(struct io_ring_ctx *ctx) +{ + return test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq) || + !llist_empty(&ctx->work_llist); +} #endif diff --git a/io_uring/napi.c b/io_uring/napi.c index 8ec0168995390..b234adda7dfd2 100644 --- a/io_uring/napi.c +++ b/io_uring/napi.c @@ -122,7 +122,7 @@ static bool io_napi_busy_loop_should_end(void *data, if (signal_pending(current)) return true; - if (io_should_wake(iowq)) + if (io_should_wake(iowq) || io_has_work(iowq->ctx)) return true; if (io_napi_busy_loop_timeout(start_time, iowq->napi_busy_poll_to)) return true; -- cgit 1.2.3-korg