diff --git a/fs/io_uring.c b/fs/io_uring.c index b40b640924db..e92029bd3936 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -169,7 +169,7 @@ struct io_rings { * The application needs a full memory barrier before checking * for IORING_SQ_NEED_WAKEUP after updating the sq tail. */ - u32 sq_flags; + atomic_t sq_flags; /* * Runtime CQ flags * @@ -2030,8 +2030,7 @@ static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force) all_flushed = list_empty(&ctx->cq_overflow_list); if (all_flushed) { clear_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq); - WRITE_ONCE(ctx->rings->sq_flags, - ctx->rings->sq_flags & ~IORING_SQ_CQ_OVERFLOW); + atomic_andnot(IORING_SQ_CQ_OVERFLOW, &ctx->rings->sq_flags); } io_commit_cqring(ctx); @@ -2125,8 +2124,7 @@ static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data, } if (list_empty(&ctx->cq_overflow_list)) { set_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq); - WRITE_ONCE(ctx->rings->sq_flags, - ctx->rings->sq_flags | IORING_SQ_CQ_OVERFLOW); + atomic_or(IORING_SQ_CQ_OVERFLOW, &ctx->rings->sq_flags); } ocqe->cqe.user_data = user_data; @@ -8108,23 +8106,6 @@ static inline bool io_sqd_events_pending(struct io_sq_data *sqd) return READ_ONCE(sqd->state); } -static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx) -{ - /* Tell userspace we may need a wakeup call */ - spin_lock(&ctx->completion_lock); - WRITE_ONCE(ctx->rings->sq_flags, - ctx->rings->sq_flags | IORING_SQ_NEED_WAKEUP); - spin_unlock(&ctx->completion_lock); -} - -static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx) -{ - spin_lock(&ctx->completion_lock); - WRITE_ONCE(ctx->rings->sq_flags, - ctx->rings->sq_flags & ~IORING_SQ_NEED_WAKEUP); - spin_unlock(&ctx->completion_lock); -} - static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries) { unsigned int to_submit; @@ -8240,8 +8221,8 @@ static int io_sq_thread(void *data) bool needs_sched = true; list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) { - io_ring_set_wakeup_flag(ctx); - + atomic_or(IORING_SQ_NEED_WAKEUP, + &ctx->rings->sq_flags); if ((ctx->flags & IORING_SETUP_IOPOLL) && !wq_list_empty(&ctx->iopoll_list)) { needs_sched = false; @@ -8266,7 +8247,8 @@ static int io_sq_thread(void *data) mutex_lock(&sqd->lock); } list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) - io_ring_clear_wakeup_flag(ctx); + atomic_andnot(IORING_SQ_NEED_WAKEUP, + &ctx->rings->sq_flags); } finish_wait(&sqd->wait, &wait); @@ -8276,7 +8258,7 @@ static int io_sq_thread(void *data) io_uring_cancel_generic(true, sqd); sqd->thread = NULL; list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) - io_ring_set_wakeup_flag(ctx); + atomic_or(IORING_SQ_NEED_WAKEUP, &ctx->rings->sq_flags); io_run_task_work(); mutex_unlock(&sqd->lock); @@ -12029,6 +12011,8 @@ static int __init io_uring_init(void) BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST); BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int)); + BUILD_BUG_ON(sizeof(atomic_t) != sizeof(u32)); + req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC | SLAB_ACCOUNT); return 0;