io_uring: allocate memory for overflowed CQEs
Instead of using a request itself for overflowed CQE stashing, allocate a separate entry. The disadvantage is that the allocation may fail and it will be accounted as lost (see rings->cq_overflow), so we lose reliability in case of memory pressure if the application is driving the CQ ring into overflow. However, it opens a way for for multiple CQEs per an SQE and even generating SQE-less CQEs. Signed-off-by:Pavel Begunkov <asml.silence@gmail.com> [axboe: use GFP_ATOMIC | __GFP_ACCOUNT] Signed-off-by:
Jens Axboe <axboe@kernel.dk>
parent
464dca61
Please register or sign in to comment