From 84f2eecf95018386c145ada19bb45b03bdb80d9e Mon Sep 17 00:00:00 2001 From: Olivier Langlois Date: Sun, 11 Aug 2024 14:07:11 -0400 Subject: io_uring/napi: check napi_enabled in io_napi_add() before proceeding doing so avoids the overhead of adding napi ids to all the rings that do not enable napi. if no id is added to napi_list because napi is disabled, __io_napi_busy_loop() will not be called. Signed-off-by: Olivier Langlois Fixes: b4ccc4dd1330 ("io_uring/napi: enable even with a timeout of 0") Link: https://lore.kernel.org/r/bd989ccef5fda14f5fd9888faf4fefcf66bd0369.1723400131.git.olivier@trillion01.com Signed-off-by: Jens Axboe --- io_uring/napi.c | 2 +- io_uring/napi.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/io_uring/napi.c b/io_uring/napi.c index a3dc3762008f..73c4159e8405 100644 --- a/io_uring/napi.c +++ b/io_uring/napi.c @@ -302,7 +302,7 @@ void __io_napi_busy_loop(struct io_ring_ctx *ctx, struct io_wait_queue *iowq) { iowq->napi_prefer_busy_poll = READ_ONCE(ctx->napi_prefer_busy_poll); - if (!(ctx->flags & IORING_SETUP_SQPOLL) && ctx->napi_enabled) + if (!(ctx->flags & IORING_SETUP_SQPOLL)) io_napi_blocking_busy_loop(ctx, iowq); } diff --git a/io_uring/napi.h b/io_uring/napi.h index 88f1c21d5548..27b88c3eb428 100644 --- a/io_uring/napi.h +++ b/io_uring/napi.h @@ -55,7 +55,7 @@ static inline void io_napi_add(struct io_kiocb *req) struct io_ring_ctx *ctx = req->ctx; struct socket *sock; - if (!READ_ONCE(ctx->napi_busy_poll_dt)) + if (!READ_ONCE(ctx->napi_enabled)) return; sock = sock_from_file(req->file); -- cgit From 48cc7ecd3a68e0fbfa281ef1ed6f6b6cb7638390 Mon Sep 17 00:00:00 2001 From: Olivier Langlois Date: Sun, 11 Aug 2024 20:34:46 -0400 Subject: io_uring/napi: remove duplicate io_napi_entry timeout assignation io_napi_entry() has 2 calling sites. One of them is unlikely to find an entry and if it does, the timeout should arguable not be updated. The other io_napi_entry() calling site is overwriting the update made by io_napi_entry() so the io_napi_entry() timeout value update has no or little value and therefore is removed. Signed-off-by: Olivier Langlois Link: https://lore.kernel.org/r/145b54ff179f87609e20dffaf5563c07cdbcad1a.1723423275.git.olivier@trillion01.com Signed-off-by: Jens Axboe --- io_uring/napi.c | 1 - 1 file changed, 1 deletion(-) diff --git a/io_uring/napi.c b/io_uring/napi.c index 73c4159e8405..1de1d4d62925 100644 --- a/io_uring/napi.c +++ b/io_uring/napi.c @@ -26,7 +26,6 @@ static struct io_napi_entry *io_napi_hash_find(struct hlist_head *hash_list, hlist_for_each_entry_rcu(e, hash_list, node) { if (e->napi_id != napi_id) continue; - e->timeout = jiffies + NAPI_TIMEOUT; return e; } -- cgit From e4956dc7a84da074fd8dc10f7abd147f15b3ae58 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 13 Aug 2024 06:10:59 -0600 Subject: io_uring/sqpoll: annotate debug task == current with data_race() There's a debug check in io_sq_thread_park() checking if it's the SQPOLL thread itself calling park. KCSAN warns about this, as we should not be reading sqd->thread outside of sqd->lock. Just silence this with data_race(). The pointer isn't used for anything but this debug check. Reported-by: syzbot+2b946a3fd80caf971b21@syzkaller.appspotmail.com Signed-off-by: Jens Axboe --- io_uring/sqpoll.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/io_uring/sqpoll.c b/io_uring/sqpoll.c index b3722e5275e7..3b50dc9586d1 100644 --- a/io_uring/sqpoll.c +++ b/io_uring/sqpoll.c @@ -44,7 +44,7 @@ void io_sq_thread_unpark(struct io_sq_data *sqd) void io_sq_thread_park(struct io_sq_data *sqd) __acquires(&sqd->lock) { - WARN_ON_ONCE(sqd->thread == current); + WARN_ON_ONCE(data_race(sqd->thread) == current); atomic_inc(&sqd->park_pending); set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state); -- cgit From 1fc2ac428ef7d2ab9e8e19efe7ec3e58aea51bf3 Mon Sep 17 00:00:00 2001 From: Caleb Sander Mateos Date: Fri, 16 Aug 2024 12:15:23 -0600 Subject: io_uring: fix user_data field name in comment io_uring_cqe's user_data field refers to `sqe->data`, but io_uring_sqe does not have a data field. Fix the comment to say `sqe->user_data`. Signed-off-by: Caleb Sander Mateos Link: https://github.com/axboe/liburing/pull/1206 Link: https://lore.kernel.org/r/20240816181526.3642732-1-csander@purestorage.com Signed-off-by: Jens Axboe --- include/uapi/linux/io_uring.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 2aaf7ee256ac..adc2524fd8e3 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -421,7 +421,7 @@ enum io_uring_msg_ring_flags { * IO completion data structure (Completion Queue Entry) */ struct io_uring_cqe { - __u64 user_data; /* sqe->data submission passed back */ + __u64 user_data; /* sqe->user_data value passed back */ __s32 res; /* result code for this event */ __u32 flags; -- cgit