Commit 4278a0de authored by Xiaoguang Wang's avatar Xiaoguang Wang Committed by Jens Axboe
Browse files

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: default avatarXiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220528015109.48039-1-xiaoguang.wang@linux.alibaba.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 8c71fe75

fs/io_uring.c

+3 −8
Original line number Diff line number Diff line
@@ -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)