1db491f77b
With more embedded systems emerging using Quark, among other things, 32-bit kernel matters again. 32-bit machine and kernel uses PAE paging, which currently wastes at least 4K of memory per process on Linux where we have to reserve an entire page to support a single 32-byte PGD structure. It would be a very good thing if we could eliminate that wastage. PAE paging is used to access more than 4GB memory on x86-32. And it is required for NX. In this patch, we still allocate one page for pgd for a Xen domain and 64-bit kernel because one page pgd is assumed in these cases. But we can save memory space by only allocating 32-byte pgd for 32-bit PAE kernel when it is not running as a Xen domain. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Lameter <cl@linux.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Glenn Williamson <glenn.p.williamson@intel.com> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1421382601-46912-1-git-send-email-fenghua.yu@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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.. | ||
kmemcheck | ||
amdtopology.c | ||
dump_pagetables.c | ||
extable.c | ||
fault.c | ||
gup.c | ||
highmem_32.c | ||
hugetlbpage.c | ||
init_32.c | ||
init_64.c | ||
init.c | ||
iomap_32.c | ||
ioremap.c | ||
kmmio.c | ||
Makefile | ||
memtest.c | ||
mm_internal.h | ||
mmap.c | ||
mmio-mod.c | ||
mpx.c | ||
numa_32.c | ||
numa_64.c | ||
numa_emulation.c | ||
numa_internal.h | ||
numa.c | ||
pageattr-test.c | ||
pageattr.c | ||
pat_internal.h | ||
pat_rbtree.c | ||
pat.c | ||
pf_in.c | ||
pf_in.h | ||
pgtable_32.c | ||
pgtable.c | ||
physaddr.c | ||
physaddr.h | ||
setup_nx.c | ||
srat.c | ||
testmmiotrace.c | ||
tlb.c |