On 4/12/22 13:26, Jens Axboe wrote:
Hi,
If we accept a connection directly, eg without installing a file
descriptor for it, or if we use IORING_OP_SOCKET in direct mode, then
we have a socket for recv/send that we can fully serialize access to.
With that in mind, we can feasibly skip locking on the socket for TCP
in that case. Some of the testing I've done has shown as much as 15%
of overhead in the lock_sock/release_sock part, with this change then
we see none.
Comments welcome!
How BH handlers (including TCP timers) and io_uring are going to run
safely ?
Even if a tcp socket had one user, (private fd opened by a non
multi-threaded
program), we would still to use the spinlock.
Maybe I am missing something, but so far your patches make no sense to me.
