diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-10-29 18:01:16 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-10-29 18:01:16 -0700 |
| commit | 4d244327dd1bab94a78fa2ab40a33d13ca18326b (patch) | |
| tree | dc75ffa4b964b1e14d31c285a30c3d470dcc42b6 | |
| parent | 3c339dbd139e14c612c521083023eabfcadfd8a5 (diff) | |
| parent | b3026767e15b488860d4bbf1649d69612bab2c25 (diff) | |
| download | linux-4d244327dd1bab94a78fa2ab40a33d13ca18326b.tar.bz2 | |
Merge tag 'io_uring-6.1-2022-10-28' of git://git.kernel.dk/linux
Pull io_uring fix from Jens Axboe:
"Just a fix for a locking regression introduced with the deferred
task_work running from this merge window"
* tag 'io_uring-6.1-2022-10-28' of git://git.kernel.dk/linux:
io_uring: unlock if __io_run_local_work locked inside
io_uring: use io_run_local_work_locked helper
| -rw-r--r-- | io_uring/io_uring.c | 11 | ||||
| -rw-r--r-- | io_uring/io_uring.h | 13 |
2 files changed, 16 insertions, 8 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 6cc16e39b27f..ac8c488e3077 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -1173,7 +1173,7 @@ static void __cold io_move_task_work_from_local(struct io_ring_ctx *ctx) } } -int __io_run_local_work(struct io_ring_ctx *ctx, bool locked) +int __io_run_local_work(struct io_ring_ctx *ctx, bool *locked) { struct llist_node *node; struct llist_node fake; @@ -1192,7 +1192,7 @@ again: struct io_kiocb *req = container_of(node, struct io_kiocb, io_task_work.node); prefetch(container_of(next, struct io_kiocb, io_task_work.node)); - req->io_task_work.func(req, &locked); + req->io_task_work.func(req, locked); ret++; node = next; } @@ -1208,7 +1208,7 @@ again: goto again; } - if (locked) + if (*locked) io_submit_flush_completions(ctx); trace_io_uring_local_work_run(ctx, ret, loops); return ret; @@ -1225,7 +1225,7 @@ int io_run_local_work(struct io_ring_ctx *ctx) __set_current_state(TASK_RUNNING); locked = mutex_trylock(&ctx->uring_lock); - ret = __io_run_local_work(ctx, locked); + ret = __io_run_local_work(ctx, &locked); if (locked) mutex_unlock(&ctx->uring_lock); @@ -1446,8 +1446,7 @@ static int io_iopoll_check(struct io_ring_ctx *ctx, long min) io_task_work_pending(ctx)) { u32 tail = ctx->cached_cq_tail; - if (!llist_empty(&ctx->work_llist)) - __io_run_local_work(ctx, true); + (void) io_run_local_work_locked(ctx); if (task_work_pending(current) || wq_list_empty(&ctx->iopoll_list)) { diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h index ef77d2aa3172..e99a79f2df9b 100644 --- a/io_uring/io_uring.h +++ b/io_uring/io_uring.h @@ -27,7 +27,7 @@ enum { struct io_uring_cqe *__io_get_cqe(struct io_ring_ctx *ctx, bool overflow); bool io_req_cqe_overflow(struct io_kiocb *req); int io_run_task_work_sig(struct io_ring_ctx *ctx); -int __io_run_local_work(struct io_ring_ctx *ctx, bool locked); +int __io_run_local_work(struct io_ring_ctx *ctx, bool *locked); int io_run_local_work(struct io_ring_ctx *ctx); void io_req_complete_failed(struct io_kiocb *req, s32 res); void __io_req_complete(struct io_kiocb *req, unsigned issue_flags); @@ -277,9 +277,18 @@ static inline int io_run_task_work_ctx(struct io_ring_ctx *ctx) static inline int io_run_local_work_locked(struct io_ring_ctx *ctx) { + bool locked; + int ret; + if (llist_empty(&ctx->work_llist)) return 0; - return __io_run_local_work(ctx, true); + + locked = true; + ret = __io_run_local_work(ctx, &locked); + /* shouldn't happen! */ + if (WARN_ON_ONCE(!locked)) + mutex_lock(&ctx->uring_lock); + return ret; } static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked) |