From: Yingxin Cheng <yingxin.cheng@intel.com>
Date: Thu, 7 Mar 2024 08:41:25 +0000 (+0800)
Subject: crimson/os/seastore/../fixed_kv_node: add comment to copy-from-source
X-Git-Tag: v19.1.1~376^2~2
X-Git-Url: http://git.apps.os.sepia.ceph.com/?a=commitdiff_plain;h=1c7993bd03c6776e295af661baae5c6f2ea50f8f;p=ceph.git

crimson/os/seastore/../fixed_kv_node: add comment to copy-from-source

Signed-off-by: Yingxin Cheng <yingxin.cheng@intel.com>
(cherry picked from commit 3df6477809f8aabacbf9850a09527c2887263949)
---

diff --git a/src/crimson/os/seastore/btree/fixed_kv_node.h b/src/crimson/os/seastore/btree/fixed_kv_node.h
index 6ad55e3b9b32f..544727f30aac8 100644
--- a/src/crimson/os/seastore/btree/fixed_kv_node.h
+++ b/src/crimson/os/seastore/btree/fixed_kv_node.h
@@ -430,6 +430,8 @@ struct FixedKVNode : ChildableCachedExtent {
 	// the foreign key is preserved
 	if (!child) {
 	  child = source.children[foreign_it.get_offset()];
+	  // child can be either valid if present, nullptr if absent,
+	  // or RESERVATION_PTR.
 	}
 	foreign_it++;
 	local_it++;