... > The way Mellanox ConnectX5 driver handles 'release of allocated pages > from HCA' or 'allocation of pages to HCA', is by sending an event to the > host. This event will have number of pages in it. If the number is > positive, that indicates HCA is requesting that number of pages to be > allocated. And if that number is negative, it is the HCA indicating that > that number of pages can be reclaimed by the host. A one line comment would do. Possibly even negating the be32toh() result? > In this patch we are restricting the maximum number of pages that can be > reclaimed to be 50000 (effectively this would be -50000 as it is > reclaim). This limit is based on the capability of the firmware as it > cannot release more than 50000 back to the host in one go. Hang on, why are you soft limiting it to the hard limit? I thought the problem was that releasing a lot of pages took a long time and 'stuffed' other time-critical tasks. The only way to resolve that would seem to be to defer the actual freeing to a low (or at least normal user) priority thread. You would definitely want to get out of 'softint' context. (Which is out of napi unless forced to be threaded - and that only really works if you force the threads under the RT scheduler.) David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
