Hi Julien > -----Original Message----- > From: Julien Grall <jul...@xen.org> > Sent: Monday, July 19, 2021 6:00 PM > To: Jan Beulich <jbeul...@suse.com>; Penny Zheng <penny.zh...@arm.com> > Cc: Bertrand Marquis <bertrand.marq...@arm.com>; Wei Chen > <wei.c...@arm.com>; nd <n...@arm.com>; xen-devel@lists.xenproject.org; > sstabell...@kernel.org > Subject: Re: [PATCH V3 08/10] xen/arm: introduce acquire_staticmem_pages > and acquire_domstatic_pages > > Hi Jan, > > On 19/07/2021 10:26, Jan Beulich wrote: > > On 15.07.2021 07:18, Penny Zheng wrote: > >> @@ -1065,6 +1069,73 @@ static struct page_info *alloc_heap_pages( > >> return pg; > >> } > >> > >> +#ifdef CONFIG_STATIC_MEMORY > >> +/* > >> + * Acquire nr_mfns contiguous reserved pages, starting at #smfn, of > >> + * static memory. > >> + */ > >> +static struct page_info *acquire_staticmem_pages(unsigned long nr_mfns, > >> + mfn_t smfn, > >> + unsigned int > >> +memflags) > > > > This and the other function not being __init, and there neither being > > any caller nor any freeing, a question is whether __init wants adding; > > patch 10 suggests so. The lack of freeing in particular means that > > domains created using static memory won't be restartable, requiring a > > host reboot instead. > > I am open to request an host reboot in case of an issue. Although, it would be > good to have code in place for that. > > Regardless the reboot part, I would still expect the domain to balloon in/out > memory. This is pretty broken today because Xen would end up to give the > memory to the heap allocator and the next allocation would be through the > heap allocate. > > For runtime "free/allocate", we may want to follow the same behavior as > direct-mapped domain (i.e. GFN == MFN): the page will not be given back to > any allocator and we only check if the page belongs to the domain on > allocation. > > So adding __init for acquire_staticmem_pages() is probably fine. > > On a side node, on v2, I have requested to keep track of the list of missing > pieces. @Penny, where can I find the list? >
Oh, sorry... I thought you were requesting a new mail list issue to track all missing pieces in ARM... And a second though here, you shall only mean the missing pieces for this patch serie. I'll do a quick sum-up here and put in the Patch v4 cover letter: TODO: - reboot domain on static allocation. - All memory-ops(hypercalls) regarding domain on static allocation to balloon in/out memory - asynchronously scrubbing PGC_reserved pages - consider domain on static allocation on NUMA-support scenario > Cheers, > > -- > Julien Grall Cheers, -- Penny Zheng
