This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


RE: [Xen-devel] RFC: 32 bits as smallest atomic size.

>>>>> "IP" == Ian Pratt <m+Ian.Pratt@xxxxxxxxxxxx> writes:

 >> Right now there is a single problematic cmpxchg user, 
 >> grant_entry_t, and the impact of the fix is tiny (make the 
 >> 'flags' member 4 bytes). Is that too large an inconvenience?

 IP> That would make grant table entries 12 bytes rather than 8 bytes, which
 IP> is not ideal given that you can end up needing quite a lot of them,
 IP> particularly when the cacheline packing is considered. 

Actually, the lock field can be 1 bit for all I care, as long as the
atomic method to change it word sized.

This is quite a reasonable request.

Xen-devel mailing list