From: Xuehan Xu <xxhdx1985126@gmail.com>
Date: Mon, 22 Aug 2022 06:51:12 +0000 (+0800)
Subject: crimson/os/seastore/async_cleaner: fill the semantic gap between backref get_mappings... 
X-Git-Tag: v18.0.0~175^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=b4d7897fc6e192cdd89aab57cb0119f9174a3c54;p=ceph.git

crimson/os/seastore/async_cleaner: fill the semantic gap between backref get_mappings and space reclaim

Signed-off-by: Xuehan Xu <xxhdx1985126@gmail.com>
---

diff --git a/src/crimson/os/seastore/async_cleaner.cc b/src/crimson/os/seastore/async_cleaner.cc
index e92f2d2092f9..3d25f054e3b1 100644
--- a/src/crimson/os/seastore/async_cleaner.cc
+++ b/src/crimson/os/seastore/async_cleaner.cc
@@ -985,6 +985,16 @@ AsyncCleaner::gc_reclaim_space_ret AsyncCleaner::gc_reclaim_space()
       reclaim_state->start_pos,
       reclaim_state->end_pos
     ).si_then([this, &t](auto pin_list) {
+      if (!pin_list.empty()) {
+	auto it = pin_list.begin();
+	auto &first_pin = *it;
+	if (first_pin->get_key() < reclaim_state->start_pos) {
+	  // BackrefManager::get_mappings may include a entry before
+	  // reclaim_state->start_pos, which is semantically inconsistent
+	  // with the requirements of the cleaner
+	  pin_list.erase(it);
+	}
+      }
       return backref_manager.retrieve_backref_extents_in_range(
         t,
         reclaim_state->start_pos,