powerpc/pseries: Add CMO paging statistics

With the addition of Cooperative Memory Overcommitment (CMO) support
for IBM Power Systems, two fields have been added to the VPA to report
paging statistics.  Add support in lparcfg to report them to userspace.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/kernel/lparcfg.c

@@ -409,6 +409,25 @@ static int lparcfg_count_active_processors(void)
 	return count;
 }
 
+static void pseries_cmo_data(struct seq_file *m)
+{
+	int cpu;
+	unsigned long cmo_faults = 0;
+	unsigned long cmo_fault_time = 0;
+
+	if (!firmware_has_feature(FW_FEATURE_CMO))
+		return;
+
+	for_each_possible_cpu(cpu) {
+		cmo_faults += lppaca[cpu].cmo_faults;
+		cmo_fault_time += lppaca[cpu].cmo_fault_time;
+	}
+
+	seq_printf(m, "cmo_faults=%lu\n", cmo_faults);
+	seq_printf(m, "cmo_fault_time_usec=%lu\n",
+		   cmo_fault_time / tb_ticks_per_usec);
+}
+
 static int pseries_lparcfg_data(struct seq_file *m, void *v)
 {
 	int partition_potential_processors;
@@ -434,6 +453,7 @@ static int pseries_lparcfg_data(struct seq_file *m, void *v)
 		parse_system_parameter_string(m);
 		parse_ppp_data(m);
 		parse_mpp_data(m);
+		pseries_cmo_data(m);
 
 		seq_printf(m, "purr=%ld\n", get_purr());
 	} else {		/* non SPLPAR case */

include/asm-powerpc/lppaca.h

@@ -125,7 +125,10 @@ struct lppaca {
 	// NOTE: This value will ALWAYS be zero for dedicated processors and
 	// will NEVER be zero for shared processors (ie, initialized to a 1).
 	volatile u32 yield_count;	// PLIC increments each dispatchx00-x03
-	u8	reserved6[124];		// Reserved                     x04-x7F
+	u32 reserved6;
+	volatile u64 cmo_faults;	// CMO page fault count         x08-x0F
+	volatile u64 cmo_fault_time;	// CMO page fault time          x10-x17
+	u8	reserved7[104];		// Reserved                     x18-x7F
 
 //=============================================================================
 // CACHE_LINE_4-5 0x0180 - 0x027F Contains PMC interrupt data