[Qemu-devel] [PATCH 2/2] new monitor command: info iostats

[Glauber Costa <glommer@redhat.com>]

This command provides per-cpu statistics on I/O that
has taken place in this cpu since the last time the command
was issued. We track reads and writes for pio and mmio.

Signed-off-by: Glauber Costa <glommer@redhat.com>
---
 monitor.c |   23 +++++++++++++++++++++++
 1 files changed, 23 insertions(+), 0 deletions(-)

diff --git a/monitor.c b/monitor.c
index f0a0bc3..f70dfe9 100644
--- a/monitor.c
+++ b/monitor.c
@@ -291,6 +291,27 @@ static CPUState *mon_get_cpu(void)
     return mon_cpu;
 }
 
+static void do_info_iostats(void)
+{
+    uint32_t total_mmio = 0;
+    uint32_t total_pio = 0;
+    CPUState *env;
+
+    mon_get_cpu();
+
+    for(env = first_cpu; env != NULL; env = env->next_cpu) {
+        term_printf("CPU%d: pio_read=%d pio_write=%d mmio_read=%d mmio_write=%d\n",
+                    env->cpu_index, env->pio_read_count, env->pio_write_count,
+                    env->mmio_read_count, env->mmio_write_count);
+        total_mmio += env->mmio_read_count + env->mmio_write_count;
+        env->mmio_read_count = env->mmio_write_count = 0;
+        total_pio += env->pio_read_count + env->pio_write_count;
+        env->pio_read_count = env->pio_write_count = 0;
+    }
+    term_printf("total: pio=%d mmio=%d\n", total_pio, total_mmio);
+}
+
+
 static void do_info_registers(void)
 {
     CPUState *env;
@@ -1473,6 +1494,8 @@ static const term_cmd_t info_cmds[] = {
       "", "show the block devices" },
     { "blockstats", "", do_info_blockstats,
       "", "show block device statistics" },
+    { "iostats", "", do_info_iostats,
+      "", "show I/O statistics"},
     { "registers", "", do_info_registers,
       "", "show the cpu registers" },
     { "cpus", "", do_info_cpus,
-- 
1.5.5.1