From 4278a0deb1f6cac40ded3362fe2a9827d7efee3d Mon Sep 17 00:00:00 2001 From: Xiaoguang Wang Date: Sat, 28 May 2022 09:51:09 +0800 Subject: io_uring: defer alloc_hint update to io_file_bitmap_set() io_file_bitmap_get() returns a free bitmap slot, but if it isn't used later, such as io_queue_rsrc_removal() returns error, in this case, we should not update alloc_hint at all, which still should be considered as a valid candidate for next io_file_bitmap_get() calls. To fix this issue, only update alloc_hint in io_file_bitmap_set(). Signed-off-by: Xiaoguang Wang Link: https://lore.kernel.org/r/20220528015109.48039-1-xiaoguang.wang@linux.alibaba.com Signed-off-by: Jens Axboe --- fs/io_uring.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) (limited to 'fs') diff --git a/fs/io_uring.c b/fs/io_uring.c index 1e5726b07b65..11524ea86f1f 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -5419,15 +5419,11 @@ static int io_file_bitmap_get(struct io_ring_ctx *ctx) unsigned long nr = ctx->nr_user_files; int ret; - if (table->alloc_hint >= nr) - table->alloc_hint = 0; - do { ret = find_next_zero_bit(table->bitmap, nr, table->alloc_hint); - if (ret != nr) { - table->alloc_hint = ret + 1; + if (ret != nr) return ret; - } + if (!table->alloc_hint) break; @@ -9682,8 +9678,7 @@ static inline void io_file_bitmap_set(struct io_file_table *table, int bit) { WARN_ON_ONCE(test_bit(bit, table->bitmap)); __set_bit(bit, table->bitmap); - if (bit == table->alloc_hint) - table->alloc_hint++; + table->alloc_hint = bit + 1; } static inline void io_file_bitmap_clear(struct io_file_table *table, int bit) -- cgit v1.2.3-59-g8ed1b