diff options
Diffstat (limited to 'arch/x86/include/asm/xen/page.h')
-rw-r--r-- | arch/x86/include/asm/xen/page.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index 1a162e559753..7068e4bb057d 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -87,6 +87,18 @@ clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, #endif /* + * The maximum amount of extra memory compared to the base size. The + * main scaling factor is the size of struct page. At extreme ratios + * of base:extra, all the base memory can be filled with page + * structures for the extra memory, leaving no space for anything + * else. + * + * 10x seems like a reasonable balance between scaling flexibility and + * leaving a practically usable system. + */ +#define XEN_EXTRA_MEM_RATIO (10) + +/* * Helper functions to write or read unsigned long values to/from * memory, when the access may fault. */ |