From 2933ae6eaa05e8db6ad33a3ca12af18d2a25358c Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Tue, 11 Apr 2023 12:06:07 +0100 Subject: [PATCH] io_uring/rsrc: refactor io_rsrc_node_switch We use io_rsrc_node_switch() coupled with io_rsrc_node_switch_start() for a bunch of cases including initialising ctx->rsrc_node, i.e. by passing NULL instead of rsrc_data. Leave it to only deal with actual node changing. For that, first remove it from io_uring_create() and add a function allocating the first node. Then also remove all calls to io_rsrc_node_switch() from files/buffers register as we already have a node installed and it does essentially nothing. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/d146fe306ff98b1a5a60c997c252534f03d423d7.1681210788.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- io_uring/io_uring.c | 5 ++--- io_uring/rsrc.c | 36 +++++++++++------------------------- io_uring/rsrc.h | 7 +++++++ 3 files changed, 20 insertions(+), 28 deletions(-) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 075bae8..9083a84 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3881,11 +3881,10 @@ static __cold int io_uring_create(unsigned entries, struct io_uring_params *p, ret = io_sq_offload_create(ctx, p); if (ret) goto err; - /* always set a rsrc node */ - ret = io_rsrc_node_switch_start(ctx); + + ret = io_rsrc_init(ctx); if (ret) goto err; - io_rsrc_node_switch(ctx, NULL); memset(&p->sq_off, 0, sizeof(p->sq_off)); p->sq_off.head = offsetof(struct io_rings, sq.head); diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index 329cc38..f2c660f 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -204,7 +204,7 @@ void io_rsrc_node_ref_zero(struct io_rsrc_node *node) } } -static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx) +struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx) { struct io_rsrc_node *ref_node; struct io_cache_entry *entry; @@ -231,23 +231,18 @@ void io_rsrc_node_switch(struct io_ring_ctx *ctx, struct io_rsrc_data *data_to_kill) __must_hold(&ctx->uring_lock) { - WARN_ON_ONCE(io_alloc_cache_empty(&ctx->rsrc_node_cache)); - WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node); + struct io_rsrc_node *node = ctx->rsrc_node; + struct io_rsrc_node *backup = io_rsrc_node_alloc(ctx); - if (data_to_kill) { - struct io_rsrc_node *rsrc_node = ctx->rsrc_node; - - rsrc_node->rsrc_data = data_to_kill; - list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list); - - data_to_kill->refs++; - /* put master ref */ - io_put_rsrc_node(ctx, rsrc_node); - ctx->rsrc_node = NULL; - } + if (WARN_ON_ONCE(!backup)) + return; - if (!ctx->rsrc_node) - ctx->rsrc_node = io_rsrc_node_alloc(ctx); + data_to_kill->refs++; + node->rsrc_data = data_to_kill; + list_add_tail(&node->node, &ctx->rsrc_ref_list); + /* put master ref */ + io_put_rsrc_node(ctx, node); + ctx->rsrc_node = backup; } int io_rsrc_node_switch_start(struct io_ring_ctx *ctx) @@ -921,9 +916,6 @@ int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, return -EMFILE; if (nr_args > rlimit(RLIMIT_NOFILE)) return -EMFILE; - ret = io_rsrc_node_switch_start(ctx); - if (ret) - return ret; ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args, &ctx->file_data); if (ret) @@ -978,7 +970,6 @@ int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, /* default it to the whole table */ io_file_table_set_alloc_range(ctx, 0, ctx->nr_user_files); - io_rsrc_node_switch(ctx, NULL); return 0; fail: __io_sqe_files_unregister(ctx); @@ -1260,9 +1251,6 @@ int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, return -EBUSY; if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS) return -EINVAL; - ret = io_rsrc_node_switch_start(ctx); - if (ret) - return ret; ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data); if (ret) return ret; @@ -1300,8 +1288,6 @@ int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, ctx->buf_data = data; if (ret) __io_sqe_buffers_unregister(ctx); - else - io_rsrc_node_switch(ctx, NULL); return ret; } diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h index 8729f2f..17dfe18 100644 --- a/io_uring/rsrc.h +++ b/io_uring/rsrc.h @@ -74,6 +74,7 @@ void io_rsrc_put_work(struct work_struct *work); void io_wait_rsrc_data(struct io_rsrc_data *data); void io_rsrc_node_destroy(struct io_ring_ctx *ctx, struct io_rsrc_node *ref_node); int io_rsrc_node_switch_start(struct io_ring_ctx *ctx); +struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx); int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx, struct io_rsrc_node *node, void *rsrc); void io_rsrc_node_switch(struct io_ring_ctx *ctx, @@ -164,6 +165,12 @@ static inline u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx) return &data->tags[table_idx][off]; } +static inline int io_rsrc_init(struct io_ring_ctx *ctx) +{ + ctx->rsrc_node = io_rsrc_node_alloc(ctx); + return ctx->rsrc_node ? 0 : -ENOMEM; +} + int io_files_update(struct io_kiocb *req, unsigned int issue_flags); int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); -- 2.7.4