[PATCH] hmp: Add "calc_dirty_rate" and "info dirty_rate" cmds

[Peter Xu <peterx@redhat.com>]

These two commands are missing when adding the QMP sister commands.  Add them,
so developers can play with them easier.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: Leonardo Bras Soares Passos <lsoaresp@redhat.com>
Cc: Chuan Zheng <zhengchuan@huawei.com>
Cc: huangy81@chinatelecom.cn
Signed-off-by: Peter Xu <peterx@redhat.com>
---
PS: I really doubt whether this is working as expected... I ran one 200MB/s
workload inside, what I measured is 20MB/s with current algorithm...  Sampling
512 pages out of 1G mem is not wise enough I guess, especially that assumes
dirty workload is spread across the memories while it's normally not the case..
---
 hmp-commands-info.hx  | 13 +++++++++++++
 hmp-commands.hx       | 14 ++++++++++++++
 include/monitor/hmp.h |  2 ++
 migration/dirtyrate.c | 43 +++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 72 insertions(+)

diff --git a/hmp-commands-info.hx b/hmp-commands-info.hx
index ab0c7aa5eea..f8a9141dd8a 100644
--- a/hmp-commands-info.hx
+++ b/hmp-commands-info.hx
@@ -880,3 +880,16 @@ SRST
   ``info replay``
     Display the record/replay information: mode and the current icount.
 ERST
+
+    {
+        .name       = "dirty_rate",
+        .args_type  = "",
+        .params     = "",
+        .help       = "show dirty rate information",
+        .cmd        = hmp_info_dirty_rate,
+    },
+
+SRST
+  ``info dirty_rate``
+    Display the vcpu dirty rate information.
+ERST
diff --git a/hmp-commands.hx b/hmp-commands.hx
index 2d21fe5ad42..4c27fb91f7d 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1727,3 +1727,17 @@ ERST
         .flags      = "p",
     },
 
+SRST
+``calc_dirty_rate`` *second*
+  Start a round of dirty rate measurement with the period specified in *second*.
+  The result of the dirty rate measurement may be observed with ``info
+  dirty_rate`` command.
+ERST
+
+    {
+        .name       = "calc_dirty_rate",
+        .args_type  = "second:l",
+        .params     = "second",
+        .help       = "start a round of guest dirty rate measurement",
+        .cmd        = hmp_calc_dirty_rate,
+    },
diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h
index 605d57287ae..3baa1058e2c 100644
--- a/include/monitor/hmp.h
+++ b/include/monitor/hmp.h
@@ -129,5 +129,7 @@ void hmp_info_replay(Monitor *mon, const QDict *qdict);
 void hmp_replay_break(Monitor *mon, const QDict *qdict);
 void hmp_replay_delete_break(Monitor *mon, const QDict *qdict);
 void hmp_replay_seek(Monitor *mon, const QDict *qdict);
+void hmp_info_dirty_rate(Monitor *mon, const QDict *qdict);
+void hmp_calc_dirty_rate(Monitor *mon, const QDict *qdict);
 
 #endif
diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
index ccb98147e89..382287d2912 100644
--- a/migration/dirtyrate.c
+++ b/migration/dirtyrate.c
@@ -20,6 +20,9 @@
 #include "ram.h"
 #include "trace.h"
 #include "dirtyrate.h"
+#include "monitor/hmp.h"
+#include "monitor/monitor.h"
+#include "qapi/qmp/qdict.h"
 
 static int CalculatingState = DIRTY_RATE_STATUS_UNSTARTED;
 static struct DirtyRateStat DirtyStat;
@@ -424,3 +427,43 @@ struct DirtyRateInfo *qmp_query_dirty_rate(Error **errp)
 {
     return query_dirty_rate_info();
 }
+
+void hmp_info_dirty_rate(Monitor *mon, const QDict *qdict)
+{
+    DirtyRateInfo *info = query_dirty_rate_info();
+
+    monitor_printf(mon, "Status: %s\n",
+                   DirtyRateStatus_str(info->status));
+    monitor_printf(mon, "Start Time: %"PRIi64" (ms)\n",
+                   info->start_time);
+    monitor_printf(mon, "Period: %"PRIi64" (sec)\n",
+                   info->calc_time);
+    monitor_printf(mon, "Dirty rate: ");
+    if (info->has_dirty_rate) {
+        monitor_printf(mon, "%"PRIi64" (MB/s)\n", info->dirty_rate);
+    } else {
+        monitor_printf(mon, "(not ready)\n");
+    }
+    g_free(info);
+}
+
+void hmp_calc_dirty_rate(Monitor *mon, const QDict *qdict)
+{
+    int64_t sec = qdict_get_try_int(qdict, "second", 0);
+    Error *err = NULL;
+
+    if (!sec) {
+        monitor_printf(mon, "Incorrect period length specified!\n");
+        return;
+    }
+
+    qmp_calc_dirty_rate(sec, &err);
+    if (err) {
+        hmp_handle_error(mon, err);
+        return;
+    }
+
+    monitor_printf(mon, "Starting dirty rate measurement with period %"PRIi64
+                   " seconds\n", sec);
+    monitor_printf(mon, "[Please use 'info dirty_rate' to check results]\n");
+}
-- 
2.31.1