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| author | Keir Fraser <keir.fraser@citrix.com> | 2009-09-22 08:18:19 +0100 |
|---|---|---|
| committer | Keir Fraser <keir.fraser@citrix.com> | 2009-09-22 08:18:19 +0100 |
| commit | 73f0173619a0017225fc185ed1a96a1a47a8a0c3 (patch) | |
| tree | 1945ed1c64da29298248b7aa3e6fcaf2a1dafa54 /xen/include/asm-x86/x86_64 | |
| parent | bac2000063ba239d33b631f6edda48cc6b57425b (diff) | |
| download | xen-73f0173619a0017225fc185ed1a96a1a47a8a0c3.tar.gz xen-73f0173619a0017225fc185ed1a96a1a47a8a0c3.tar.bz2 xen-73f0173619a0017225fc185ed1a96a1a47a8a0c3.zip | |
x86: map frame table sparsely
Avoid backing frame table holes with memory, when those holes are
large enough to cover an exact multiple of large pages. This is based
on the introduction of a bit map, where each bit represents one such
range, thus allowing mfn_valid() checks to easily filter out those
MFNs that now shouldn't be used to index the frame table.
This allows for saving a couple of 2M pages even on "normal" systems.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Diffstat (limited to 'xen/include/asm-x86/x86_64')
| -rw-r--r-- | xen/include/asm-x86/x86_64/page.h | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/xen/include/asm-x86/x86_64/page.h b/xen/include/asm-x86/x86_64/page.h index 8bdf9b7365..78a79c59e3 100644 --- a/xen/include/asm-x86/x86_64/page.h +++ b/xen/include/asm-x86/x86_64/page.h @@ -35,7 +35,7 @@ /* Physical address where Xen was relocated to. */ extern unsigned long xen_phys_start; -extern unsigned long max_page, max_pdx; +extern unsigned long max_pdx; extern unsigned long pfn_pdx_bottom_mask, ma_va_bottom_mask; extern unsigned int pfn_pdx_hole_shift; extern unsigned long pfn_hole_mask; @@ -53,10 +53,7 @@ extern void pfn_pdx_hole_setup(unsigned long); #define pdx_to_virt(pdx) ((void *)(DIRECTMAP_VIRT_START + \ ((unsigned long)(pdx) << PAGE_SHIFT))) -static inline int __mfn_valid(unsigned long mfn) -{ - return mfn < max_page && !(mfn & pfn_hole_mask); -} +extern int __mfn_valid(unsigned long mfn); static inline unsigned long pfn_to_pdx(unsigned long pfn) { |