From 8c9bd898fd6532c72962eee8903b075a7d673169 Mon Sep 17 00:00:00 2001
From: JiahuaChen <garfieldjia@qq.com>
Date: Fri, 3 Nov 2023 09:40:03 +0000
Subject: [PATCH] Fix ObMultipleMerge not refreshed during
 ObTableScanIterator::rescan

---
 src/storage/access/ob_multiple_merge.cpp      |  1 +
 src/storage/access/ob_table_scan_iterator.cpp | 27 +++++++++++++++++++
 src/storage/access/ob_table_scan_iterator.h   |  1 +
 src/storage/meta_mem/ob_tablet_handle.h       |  9 +++++--
 4 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/src/storage/access/ob_multiple_merge.cpp b/src/storage/access/ob_multiple_merge.cpp
index 7dd33026c9..01437f99f2 100644
--- a/src/storage/access/ob_multiple_merge.cpp
+++ b/src/storage/access/ob_multiple_merge.cpp
@@ -1239,6 +1239,7 @@ int ObMultipleMerge::refresh_tablet_iter()
         false/*allow_not_ready*/))) {
       LOG_WARN("failed to refresh tablet iterator", K(ret), K_(get_table_param), KP_(access_param));
     } else {
+      get_table_param_->refreshed_merge_ = this;
       access_param_->iter_param_.rowkey_read_info_ =
         &(get_table_param_->tablet_iter_.get_tablet_handle().get_obj()->get_rowkey_read_info());
     }
diff --git a/src/storage/access/ob_table_scan_iterator.cpp b/src/storage/access/ob_table_scan_iterator.cpp
index 6e9d44a9d9..fc38dadda2 100755
--- a/src/storage/access/ob_table_scan_iterator.cpp
+++ b/src/storage/access/ob_table_scan_iterator.cpp
@@ -205,6 +205,8 @@ int ObTableScanIterator::rescan(ObTableScanParam &scan_param)
       LOG_WARN("Failed to rescan reuse", K(ret));
     } else if (OB_FAIL(table_scan_range_.init(*scan_param_))) {
       STORAGE_LOG(WARN, "Failed to init table scan range", K(ret));
+    } else if (OB_FAIL(rescan_for_iter())) {
+      STORAGE_LOG(WARN, "Failed to switch param for iter", K(ret), K(*this));
     } else if (OB_FAIL(open_iter())) {
       STORAGE_LOG(WARN, "fail to open iter", K(ret));
     } else {
@@ -281,6 +283,31 @@ int ObTableScanIterator::switch_param(ObTableScanParam &scan_param, const ObTabl
   return ret;
 }
 
+int ObTableScanIterator::rescan_for_iter()
+{
+#define RESET_NOT_REFRESHED_ITER(refreshed_iter, iter) \
+  if (refreshed_iter != (void*)iter) {                 \
+    reset_scan_iter(iter);                             \
+  }                                                    \
+
+  int ret = OB_SUCCESS;
+  if (OB_LIKELY(nullptr == get_table_param_.refreshed_merge_)) {
+    // do nothing
+  } else {
+    RESET_NOT_REFRESHED_ITER(get_table_param_.refreshed_merge_, single_merge_);
+    RESET_NOT_REFRESHED_ITER(get_table_param_.refreshed_merge_, get_merge_);
+    RESET_NOT_REFRESHED_ITER(get_table_param_.refreshed_merge_, scan_merge_);
+    RESET_NOT_REFRESHED_ITER(get_table_param_.refreshed_merge_, multi_scan_merge_);
+    RESET_NOT_REFRESHED_ITER(get_table_param_.refreshed_merge_, skip_scan_merge_);
+    RESET_NOT_REFRESHED_ITER(get_table_param_.refreshed_merge_, memtable_row_sample_iterator_);
+    RESET_NOT_REFRESHED_ITER(get_table_param_.refreshed_merge_, row_sample_iterator_);
+    RESET_NOT_REFRESHED_ITER(get_table_param_.refreshed_merge_, block_sample_iterator_);
+    get_table_param_.refreshed_merge_ = nullptr;
+  }
+#undef RESET_NOT_REFRESHED_ITER
+  return ret;
+}
+
 int ObTableScanIterator::switch_param_for_iter()
 {
 #define SWITCH_PARAM_FOR_ITER(iter, ret)                                        \
diff --git a/src/storage/access/ob_table_scan_iterator.h b/src/storage/access/ob_table_scan_iterator.h
index e03186149d..5fd55ce0b4 100644
--- a/src/storage/access/ob_table_scan_iterator.h
+++ b/src/storage/access/ob_table_scan_iterator.h
@@ -75,6 +75,7 @@ private:
   template<typename T> void reset_scan_iter(T *&iter);
   int switch_scan_param(ObMultipleMerge &iter);
   void reuse_row_iters();
+  int rescan_for_iter();
   int switch_param_for_iter();
   int open_iter();
 
diff --git a/src/storage/meta_mem/ob_tablet_handle.h b/src/storage/meta_mem/ob_tablet_handle.h
index 6e9a931e19..74db482a03 100644
--- a/src/storage/meta_mem/ob_tablet_handle.h
+++ b/src/storage/meta_mem/ob_tablet_handle.h
@@ -103,10 +103,10 @@ private:
   ObTabletHandle *transfer_src_handle_;
 };
 
-struct ObGetTableParam
+struct ObGetTableParam final
 {
 public:
-  ObGetTableParam() : frozen_version_(-1), sample_info_(), tablet_iter_() {}
+  ObGetTableParam() : frozen_version_(-1), sample_info_(), tablet_iter_(), refreshed_merge_(nullptr) {}
   ~ObGetTableParam() { reset(); }
   bool is_valid() const { return tablet_iter_.is_valid(); }
   void reset()
@@ -114,12 +114,17 @@ public:
     frozen_version_ = -1;
     sample_info_.reset();
     tablet_iter_.reset();
+    refreshed_merge_ = nullptr;
   }
   TO_STRING_KV(K_(frozen_version), K_(sample_info), K_(tablet_iter));
 public:
   int64_t frozen_version_;
   common::SampleInfo sample_info_;
   ObTabletTableIterator tablet_iter_;
+
+  // when tablet has been refreshed, to notify other ObMultipleMerge in ObTableScanIterator re-inited
+  // before rescan.
+  void *refreshed_merge_;
   DISALLOW_COPY_AND_ASSIGN(ObGetTableParam);
 };