powerpc/pseries: CMO unused page hinting
Adds support for the "unused" page hint which can be used in shared
memory partitions to flag pages not in use, which will then be stolen
before active pages by the hypervisor when memory needs to be moved to
LPARs in need of additional memory. Failure to mark pages as 'unused'
makes the LPAR slower to give up unused memory to other partitions.
This adds the kernel parameter 'cmo_free_hint' to disable this
functionality.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index 32cbf16..4940662 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -231,6 +231,11 @@
struct page *p);
extern int page_is_ram(unsigned long pfn);
+#ifdef CONFIG_PPC_SMLPAR
+void arch_free_page(struct page *page, int order);
+#define HAVE_ARCH_FREE_PAGE
+#endif
+
struct vm_area_struct;
typedef struct page *pgtable_t;