[PATCH v2 03/10] migration/dirtyrate: Add dirtyrate statistics series functions

[Chuan Zheng <zhengchuan@huawei.com>]

From: Zheng Chuan <zhengchuan@huawei.com>

Add dirtyrate statistics to record/update dirtyrate info.

Signed-off-by: Zheng Chuan <zhengchuan@huawei.com>
---
 migration/dirtyrate.c | 30 ++++++++++++++++++++++++++++++
 migration/dirtyrate.h | 10 ++++++++++
 2 files changed, 40 insertions(+)

diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
index bb0ebe9..8708090 100644
--- a/migration/dirtyrate.c
+++ b/migration/dirtyrate.c
@@ -24,6 +24,7 @@
 #include "dirtyrate.h"
 
 CalculatingDirtyRateState CalculatingState = CAL_DIRTY_RATE_INIT;
+static struct DirtyRateStat dirty_stat;
 
 static int dirty_rate_set_state(int new_state)
 {
@@ -40,6 +41,35 @@ static int dirty_rate_set_state(int new_state)
     return 0;
 }
 
+static void reset_dirtyrate_stat(void)
+{
+    dirty_stat.total_dirty_samples = 0;
+    dirty_stat.total_sample_count = 0;
+    dirty_stat.total_block_mem_MB = 0;
+    dirty_stat.dirty_rate = 0;
+}
+
+static void update_dirtyrate_stat(struct RamblockDirtyInfo *info)
+{
+    dirty_stat.total_dirty_samples += info->sample_dirty_count;
+    dirty_stat.total_sample_count += info->sample_pages_count;
+    /* size of 4K pages in MB */
+    dirty_stat.total_block_mem_MB += info->ramblock_pages / 256;
+}
+
+static void update_dirtyrate(uint64_t msec)
+{
+    uint64_t dirty_rate;
+    unsigned int total_dirty_samples = dirty_stat.total_dirty_samples;
+    unsigned int total_sample_count = dirty_stat.total_sample_count;
+    size_t total_block_mem_MB = dirty_stat.total_block_mem_MB;
+
+    dirty_rate = total_dirty_samples * total_block_mem_MB *
+                 1000 / (total_sample_count * msec);
+
+    dirty_stat.dirty_rate = dirty_rate;
+}
+
 static void calculate_dirtyrate(struct DirtyRateConfig config)
 {
     /* todo */
diff --git a/migration/dirtyrate.h b/migration/dirtyrate.h
index 9650566..af57c80 100644
--- a/migration/dirtyrate.h
+++ b/migration/dirtyrate.h
@@ -57,6 +57,16 @@ struct RamblockDirtyInfo {
     uint8_t *hash_result; /* array of hash result for sampled pages */
 };
 
+/*
+ * Store calculate statistics for each measure.
+ */
+struct DirtyRateStat {
+    unsigned int total_dirty_samples; /* total dirty pages for this measure */
+    unsigned int total_sample_count; /* total sampled pages for this measure */
+    size_t total_block_mem_MB; /* size of sampled pages in MB */
+    int64_t dirty_rate; /* dirty rate for this measure */
+};
+
 void *get_dirtyrate_thread(void *arg);
 #endif
 
-- 
1.8.3.1