[PATCH v3 06/10] migration/dirtyrate: Compare page hash results for recorded sampled page

[Chuan Zheng]

Compare page hash results for recorded sampled page.

Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
Signed-off-by: YanYing Zhuang <ann.zhuangyanying@huawei.com>
---
 migration/dirtyrate.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)

diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
index 62b6f69..3ce25f5 100644
--- a/migration/dirtyrate.c
+++ b/migration/dirtyrate.c
@@ -215,6 +215,82 @@ static int record_ramblock_hash_info(struct 
RamblockDirtyInfo **block_dinfo,
     return 0;
 }
 
+static int calc_page_dirty_rate(struct RamblockDirtyInfo *info)
+{
+    uint8_t *md = NULL;
+    int i;
+    int ret = 0;
+
+    md = g_try_new0(uint8_t, qcrypto_hash_len);
+    if (!md) {
+        return -1;
+    }
+
+    for (i = 0; i < info->sample_pages_count; i++) {
+        ret = get_ramblock_vfn_hash(info, info->sample_page_vfn[i], &md);
+        if (ret < 0) {
+            goto out;
+        }
+
+        if (memcmp(md, info->hash_result + i * qcrypto_hash_len,
+                   qcrypto_hash_len) != 0) {
+            info->sample_dirty_count++;
+        }
+    }
+
+out:
+    g_free(md);
+    return ret;
+}
+
+static bool find_page_matched(RAMBlock *block, struct RamblockDirtyInfo *infos,
+                              int count, struct RamblockDirtyInfo **matched)
+{
+    int i;
+
+    for (i = 0; i < count; i++) {
+        if (!strcmp(infos[i].idstr, qemu_ram_get_idstr(block))) {
+            break;
+        }
+    }
+
+    if (i == count) {
+        return false;
+    }
+
+    if (infos[i].ramblock_addr != qemu_ram_get_host_addr(block) ||
+        infos[i].ramblock_pages !=
+            (qemu_ram_get_used_length(block) >> 12)) {
+        return false;
+    }
+
+    *matched = &infos[i];
+    return true;
+}
+
+static int compare_page_hash_info(struct RamblockDirtyInfo *info,
+                                  int block_index)
+{
+    struct RamblockDirtyInfo *block_dinfo = NULL;
+    RAMBlock *block = NULL;
+
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
+        block_dinfo = NULL;
+        if (!find_page_matched(block, info, block_index + 1, &block_dinfo)) {
+            continue;
+        }
+        if (calc_page_dirty_rate(block_dinfo) < 0) {
+            return -1;
+        }
+        update_dirtyrate_stat(block_dinfo);
+    }
+    if (!dirty_stat.total_sample_count) {
+        return -1;
+    }
+
+    return 0;
+}
+
 static void calculate_dirtyrate(struct DirtyRateConfig config)
 {
     /* todo */
-- 
1.8.3.1