[PULL 06/26] migration/dirtyrate: Add dirtyrate statistics series functions

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: Chuan Zheng <zhengchuan@huawei.com>

Add dirtyrate statistics functions to record/update dirtyrate info.

Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Message-Id: <1600237327-33618-5-git-send-email-zhengchuan@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/dirtyrate.c | 32 ++++++++++++++++++++++++++++++++
 migration/dirtyrate.h | 12 ++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
index 3edf000f45..94c4e173bc 100644
--- a/migration/dirtyrate.c
+++ b/migration/dirtyrate.c
@@ -23,6 +23,7 @@
 #include "dirtyrate.h"
 
 static int CalculatingState = DIRTY_RATE_STATUS_UNSTARTED;
+static struct DirtyRateStat DirtyStat;
 
 static int dirtyrate_set_state(int *state, int old_state, int new_state)
 {
@@ -34,6 +35,37 @@ static int dirtyrate_set_state(int *state, int old_state, int new_state)
     }
 }
 
+static void reset_dirtyrate_stat(void)
+{
+    DirtyStat.total_dirty_samples = 0;
+    DirtyStat.total_sample_count = 0;
+    DirtyStat.total_block_mem_MB = 0;
+    DirtyStat.dirty_rate = -1;
+    DirtyStat.start_time = 0;
+    DirtyStat.calc_time = 0;
+}
+
+static void update_dirtyrate_stat(struct RamblockDirtyInfo *info)
+{
+    DirtyStat.total_dirty_samples += info->sample_dirty_count;
+    DirtyStat.total_sample_count += info->sample_pages_count;
+    /* size of total pages in MB */
+    DirtyStat.total_block_mem_MB += (info->ramblock_pages *
+                                     TARGET_PAGE_SIZE) >> 20;
+}
+
+static void update_dirtyrate(uint64_t msec)
+{
+    uint64_t dirtyrate;
+    uint64_t total_dirty_samples = DirtyStat.total_dirty_samples;
+    uint64_t total_sample_count = DirtyStat.total_sample_count;
+    uint64_t total_block_mem_MB = DirtyStat.total_block_mem_MB;
+
+    dirtyrate = total_dirty_samples * total_block_mem_MB *
+                1000 / (total_sample_count * msec);
+
+    DirtyStat.dirty_rate = dirtyrate;
+}
 
 static void calculate_dirtyrate(struct DirtyRateConfig config)
 {
diff --git a/migration/dirtyrate.h b/migration/dirtyrate.h
index 8707df852d..312debca6f 100644
--- a/migration/dirtyrate.h
+++ b/migration/dirtyrate.h
@@ -42,5 +42,17 @@ struct RamblockDirtyInfo {
     uint32_t *hash_result; /* array of hash result for sampled pages */
 };
 
+/*
+ * Store calculation statistics for each measure.
+ */
+struct DirtyRateStat {
+    uint64_t total_dirty_samples; /* total dirty sampled page */
+    uint64_t total_sample_count; /* total sampled pages */
+    uint64_t total_block_mem_MB; /* size of total sampled pages in MB */
+    int64_t dirty_rate; /* dirty rate in MB/s */
+    int64_t start_time; /* calculation start time in units of second */
+    int64_t calc_time; /* time duration of two sampling in units of second */
+};
+
 void *get_dirtyrate_thread(void *arg);
 #endif
-- 
2.26.2