Subject: [PATCH 0/3] powerpc: Instrument Hypervisor Calls: add sysfs files

From: Mike Kravetz <[email-masked]>
Date: Tue, 13 Jun 2006 20:54:20 -0700

Make statistics available via files in sysfs.

-- 
Signed-off-by: Mike Kravetz <[email-masked]>

diff -Naupr linux-2.6.17-rc6/arch/powerpc/kernel/sysfs.c linux-2.6.17-rc6.work/arch/powerpc/kernel/sysfs.c
--- linux-2.6.17-rc6/arch/powerpc/kernel/sysfs.c	2006-06-06 00:57:02.000000000 +0000
+++ linux-2.6.17-rc6.work/arch/powerpc/kernel/sysfs.c	2006-06-13 21:42:32.000000000 +0000
@@ -356,6 +356,39 @@ static ssize_t show_physical_id(struct s
 }
 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 
+#ifdef CONFIG_HCALL_STATS
+DECLARE_PER_CPU(struct hcall_stats[MAX_HCALL_OPCODES+1], hcall_stats);
+
+static ssize_t show_hcall_stats(struct sys_device *dev, char *buf)
+{
+	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
+	struct hcall_stats *hs = per_cpu(hcall_stats, cpu->sysdev.id);
+	size_t rc = 0;
+	size_t b_written = 0;
+	size_t b_remain = PAGE_SIZE;
+	unsigned long i;
+
+	for (i=0; i<MAX_HCALL_OPCODES+1; i++){
+		if (!hs[i].num_calls)
+			continue;
+
+		b_written = snprintf(buf+rc, b_remain,
+				"%lu %lu %lu\n",
+				i<<2, hs[i].num_calls, hs[i].total_time);
+
+		if (b_written >= b_remain)
+			break;	/* end of buffer */
+
+		rc += b_written;
+		b_remain -= b_written;
+	}
+
+	return rc;
+}
+
+static SYSDEV_ATTR(hcall_stats, 0666, show_hcall_stats, NULL);
+#endif /* CONFIG_HCALL_STATS */
+
 static int __init topology_init(void)
 {
 	int cpu;
@@ -390,6 +423,9 @@ static int __init topology_init(void)
 			register_cpu(c, cpu, parent);
 
 			sysdev_create_file(&c->sysdev, &attr_physical_id);
+#ifdef CONFIG_HCALL_STATS
+			sysdev_create_file(&c->sysdev, &attr_hcall_stats);
+#endif
 		}
 
 		if (cpu_online(cpu))