On Mon, Feb 10, 2025 at 03:57:27PM +0800, Herbert Xu wrote: > On Sun, Feb 09, 2025 at 08:34:30AM -0800, Eric Biggers wrote: > > > > Or just make it synchronous which would be way easier, and the calling code uses > > it synchronously anyway. > > Note that synchronous in general does not make the problem go away. > The important thing here is to give congestion feedback in the form > of EBUSY which tells the user to stop generating more data until a > callback is made. > > While synchronous can be a form of congestion control by requiring > an extra thread for each waiting request, it doesn't really give > that feedback to the upper level. > Which is of course entirely theoretical, given that the proposed user waits synchronously for each request to complete anyway. And hardly anyone wants to do otherwise since it is way too much of a pain. - Eric
