Matthew Wilcox - 24.11.17, 22:18: > On Fri, Nov 24, 2017 at 07:01:31PM +0100, Martin Steigerwald wrote: > > > The XArray is an abstract data type which behaves like an infinitely > > > large array of pointers. The index into the array is an unsigned long. > > > A freshly-initialised XArray contains a NULL pointer at every index. > > > > Yes, I think this is clearer already. > > > > Maybe with a few sentences on "Why does the kernel provide this?", "Where > > is it used?" (if already known), "What use case is it suitable for – if I > > want to implement something into the kernel (or in user space?) ?" and > > probably "How does it differ from user data structures the kernel > > provides?" > > OK, I think this is getting more useful. Here's what I currently have: > > Overview > ======== > > The XArray is an abstract data type which behaves like a very large array > of pointers. It meets many of the same needs as a hash or a conventional > resizable array. Unlike a hash, it allows you to sensibly go to the > next or previous entry in a cache-efficient manner. In contrast to > a resizable array, there is no need for copying data or changing MMU > mappings in order to grow the array. It is more memory-efficient, > parallelisable and cache friendly than a doubly-linked list. It takes > advantage of RCU to perform lookups without locking. I like this. I bet I may not be able help much further with it other than to possibly proofread it tomorrow. Thank you for considering my suggestion. -- Martin
