On 06.03.2020 14:41, Paul Durrant wrote: >> -----Original Message----- >> From: Jan Beulich <jbeul...@suse.com> >> Sent: 06 March 2020 13:36 >> To: Paul Durrant <xadimg...@gmail.com> >> Cc: sstabell...@kernel.org; jul...@xen.org; volodymyr_babc...@epam.com; >> w...@xen.org; >> konrad.w...@oracle.com; andrew.coop...@citrix.com; ian.jack...@eu.citrix.com; >> george.dun...@citrix.com; xen-devel@lists.xenproject.org; 'David Woodhouse' >> <dw...@infradead.org> >> Subject: Re: [PATCH 2/2] domain: use PGC_extra domheap page for shared_info >> >> On 06.03.2020 14:26, Paul Durrant wrote: >>>> From: Xen-devel <xen-devel-boun...@lists.xenproject.org> On Behalf Of Jan >>>> Beulich >>>> Sent: 06 March 2020 13:24 >>>> >>>> On 06.03.2020 14:13, Paul Durrant wrote: >>>>> My aim is to make the separation abundantly obvious by getting rid >>>>> of shared xenheap pages (for non-system domains at least) but I >>>>> can't do that before converting shared_info and grant shared/status >>>>> frames to domheap. >>>> >>>> Following David's various replies - instead of going this route of >>>> replacing the sharing of xenheap pages by different logic, the >>>> same ought to be achievable by making the backing allocations come >>>> from the correct pool? >>>> >>> >>> I still prefer the simplification of not having to clean up the >>> shared xenheap page list in domain_kill() so IMO it is still worth >>> it for that alone. >> >> I don't see anything very special with the cleaning up in >> domain_kill() / domain_relinquish_resources(). What I'd view as >> more desirable in this regard is the general fact of needing >> two lists. But you realize there's a downside to this as well? >> dump_pageframe_info() will reliably show _all_ Xen heap pages >> associated with a domain, but it will only ever show up to 10 >> pages on ->page_list for a domain that's not already being >> cleaned up. > > That's not much of a downside though I don't think. The xenheap > (or PGC_extra domheap pages) are 'special' and so info about > them ought to be available via an alternate dump function anyway > (and if not already, it can be added).
Whatever you'd add, the logic would need to either traverse the entire ->page_list (can take very long) or have/use out of band information where such pages may have a record (fragile). Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
