On Wed, Oct 16, 2024 at 10:23:14AM -0400, Waiman Long wrote: > Another alternative that I have been thinking about is a down_read() variant > with intention to upgrade later. This will ensure that only one active > reader is allowed to upgrade later. With this, upgrade_read() will always > succeed, maybe with some sleeping, as long as the correct down_read() is > used. How is that different from Kent's SIX locks other than you can take an rwsem for write immediately (SIX locks have to be taken for Intent and then Upgraded)?