powerpc: Hugetlb for BookE

Enable hugepages on Freescale BookE processors.  This allows the kernel to
use huge TLB entries to map pages, which can greatly reduce the number of
TLB misses and the amount of TLB thrashing experienced by applications with
large memory footprints.  Care should be taken when using this on FSL
processors, as the number of large TLB entries supported by the core is low
(16-64) on current processors.

The supported set of hugepage sizes include 4m, 16m, 64m, 256m, and 1g.
Page sizes larger than the max zone size are called "gigantic" pages and
must be allocated on the command line (and cannot be deallocated).

This is currently only fully implemented for Freescale 32-bit BookE
processors, but there is some infrastructure in the code for
64-bit BooKE.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Becky Bruce
2011-06-28 09:54:48 +00:00
committed by Benjamin Herrenschmidt
parent 7df5659eef
commit 41151e77a4
20 changed files with 765 additions and 105 deletions

View File

@ -262,8 +262,7 @@ extern void hash_failure_debug(unsigned long ea, unsigned long access,
extern int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
unsigned long pstart, unsigned long prot,
int psize, int ssize);
extern void add_gpage(unsigned long addr, unsigned long page_size,
unsigned long number_of_pages);
extern void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages);
extern void demote_segment_4k(struct mm_struct *mm, unsigned long addr);
extern void hpte_init_native(void);