> From: Jan Beulich [mailto:jbeul...@suse.com] > Sent: Friday, December 05, 2014 12:29 AM > > >>> On 01.12.14 at 10:24, <tiejun.c...@intel.com> wrote: > > In some cases like igd_opregion_pgbase, guest will use mem_hole_alloc > > to allocate some memory to use in runtime cycle, so we alsoe need to > > make sure all reserved device memory don't overlap such a region. > > While ideally this would get switched to the model outlined for > the previous two patches too, it's at least reasonable to keep > this simple allocator simple for the time being. > > > --- a/tools/firmware/hvmloader/util.c > > +++ b/tools/firmware/hvmloader/util.c > > @@ -416,9 +416,29 @@ static uint32_t alloc_down = > RESERVED_MEMORY_DYNAMIC_END; > > > > xen_pfn_t mem_hole_alloc(uint32_t nr_mfns) > > { > > + unsigned int i, num = hvm_get_reserved_device_memory_map(); > > + uint64_t rdm_start, rdm_end; > > + uint32_t alloc_start, alloc_end; > > + > > alloc_down -= nr_mfns << PAGE_SHIFT; > > + alloc_start = alloc_down; > > + alloc_end = alloc_start + (nr_mfns << PAGE_SHIFT); > > + for ( i = 0; i < num; i++ ) > > + { > > + rdm_start = (uint64_t)rdm_map[i].start_pfn << PAGE_SHIFT; > > + rdm_end = rdm_start + ((uint64_t)rdm_map[i].nr_pages << > PAGE_SHIFT); > > + if ( check_rdm_hole_conflict((uint64_t)alloc_start, > > + (uint64_t)alloc_end, > > Pointless casts. > > > + rdm_start, rdm_end - > rdm_start) ) > > + { > > + alloc_end = rdm_start; > > + alloc_start = alloc_end - (nr_mfns << PAGE_SHIFT); > > + BUG_ON(alloc_up >= alloc_start); > > This is redundant with the BUG_ON() below afaict. Or at least it > would be, if you would properly update allow_down (if you don't > you may end up returning the same PFN for two allocations). >
I'd like this being done once at init time. Once alloc_up/down is verified/adjusted, no need to add run-time overhead here. Thanks Kevin _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
