Li, Xin B
2006-Feb-27 14:13 UTC
RE: [Xen-devel] Re: Will map_domain_page return NULL when fails onx86_32?
>>>> Hi Keir, just a curious question, will map_domain_page >>> return NULL when >>>> fails on x86_32? If not, why? >>>> thanks >>> >>> I don''t expect that it should ever fail. It''s used for temporary >>> mappings (e.g., scope of a function) and so even though the mapping >>> space is finite, we shouldn''t ever exhaust it. >> >> So the unmap is not a must? >> Can you explain the mechanism of garbage collection here? >> Thanks > >The unmap is a must. After unmap the mapping is put in a per-vcpu >lookup table to allow fast reuse. When it is evicted from that table >then it is freed.Quite clear, thanks, this may be helpful to accelerate __entry(). -Xin> > -- Keir > > >_______________________________________________ >Xen-devel mailing list >Xen-devel@lists.xensource.com >http://lists.xensource.com/xen-devel >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel