powerpc/pseries: Add page coalescing support

Adds support for page coalescing, which is a feature on IBM Power servers
which allows for coalescing identical pages between logical partitions.
Hint text pages as coalesce candidates, since they are the most likely
pages to be able to be coalesced between partitions. This patch also
exports some page coalescing statistics available from firmware via
lparcfg.

[BenH: Moved a couple of things around to fix compile problems]

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 7839bd7bfd1..c016033ba78 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -700,8 +700,10 @@ static void __init early_cmdline_parse(void)
 #endif /* CONFIG_PCI_MSI */
 #ifdef CONFIG_PPC_SMLPAR
 #define OV5_CMO                 0x80    /* Cooperative Memory Overcommitment */
+#define OV5_XCMO                        0x40    /* Page Coalescing */
 #else
 #define OV5_CMO                 0x00
+#define OV5_XCMO                        0x00
 #endif
 #define OV5_TYPE1_AFFINITY      0x80    /* Type 1 NUMA affinity */
 
@@ -756,7 +758,7 @@ static unsigned char ibm_architecture_vec[] = {
         OV5_LPAR | OV5_SPLPAR | OV5_LARGE_PAGES | OV5_DRCONF_MEMORY |
         OV5_DONATE_DEDICATE_CPU | OV5_MSI,
         0,
-        OV5_CMO,
+        OV5_CMO | OV5_XCMO,
         OV5_TYPE1_AFFINITY,
         0,
         0,