Re: [Lhms-devel] [PATCH 4/4] V4 ia64 SPARSEMEM - SPARSEMEM code changes

Bob Picco
2005-09-22T17:59:38Z

Dave Hansen wrote: [Thu Sep 22 2005, 12:36:16PM EDT]
> On Thu, 2005-09-22 at 12:14 -0400, Bob Picco wrote:
> > This patch is the minimal set of changes required by ia64 to use
> > SPARSEMEM.
>
> I have a couple of little style comments.
>
> > +#ifdef CONFIG_SPARSEMEM
> > + efi_memmap_walk(register_sparse_mem, NULL);
> > +#endif
> > + sparse_init();
> > +
> > efi_memmap_walk(filter_rsvd_memory, count_node_pages);
> >
> > +#ifdef CONFIG_VIRTUAL_MEM_MAP
> > vmalloc_end -= PAGE_ALIGN(max_low_pfn * sizeof(struct page));
> > vmem_map = (struct page *) vmalloc_end;
> > efi_memmap_walk(create_mem_map_page_table, NULL);
> > printk("Virtual mem_map starts at 0x%p\n", vmem_map);
> > +#endif
>
> It would be nice if these kind of .c file #ifdefs could be broken out a
> little more. For instance, you could make an arch_sparse_init() that
> does all of the sparsemem bits, and make it a do{}while(0) when !
> CONFIG_SPARSEMEM.
I could do this. It would eliminate one conditional. Eventually I'm hope
for only SPARSEMEM but that is a ways off.
>
> > for_each_online_node(node) {
> > memset(zones_size, 0, sizeof(zones_size));
> > @@ -690,7 +722,9 @@ void __init paging_init(void)
> >
> > pfn_offset = mem_data[node].min_pfn;
> >
> > +#ifdef CONFIG_VIRTUAL_MEM_MAP
> > NODE_DATA(node)->node_mem_map = vmem_map + pfn_offset;
> > +#endif
>
> Is CONFIG_FLAT_NODE_MEM_MAP more appropriate here? That's how
> ->node_mem_map is #ifdef'd to begin with in mmzone.h.
Well I think this is doable but probaably shouldn't. This code is very
specific to CONFIG_VIRTUAL_MEM_MAP.
>
> > --- linux-2.6.14-rc2.orig/arch/ia64/mm/numa.c 2005-09-21 12:28:49.000000000 -0400
> > +++ linux-2.6.14-rc2/arch/ia64/mm/numa.c 2005-09-21 12:29:05.000000000 -0400
> > @@ -45,5 +45,30 @@ paddr_to_nid(unsigned long paddr)
> > paddr < node_memblk[i].start_paddr + node_memblk[i].size)
> > break;
> >
> > - return (i < num_node_memblks) ? node_memblk[i].nid : (num_node_memblks ? -1 : 0);
> > + return (i < num_node_memblks) ?
> > + node_memblk[i].nid : (num_node_memblks ? -1 : 0);
> > }
>
> Looks like just a whitespace change.
Oh dam. This shouldn't have been introduced. It's not part of SPARSEMEM.
>
> -- Dave
bob
>