crimson/os/seastore: assert the committing delta is not empty

It makes no sense to commit an empty delta. It is mostly an issue that
user forget to generate delta during mutation, or there are futile
copy-on-write operations.

Signed-off-by: Yingxin Cheng <yingxin.cheng@intel.com>

diff --git a/src/crimson/os/seastore/cache.cc b/src/crimson/os/seastore/cache.cc
index 10c38d066f584da9e140429007a6585e41d25fb1..e1727e0aac90767609790b57ad14bf0df6e7964f 100644 (file)
--- a/src/crimson/os/seastore/cache.cc
+++ b/src/crimson/os/seastore/cache.cc
@@ -573,6 +573,7 @@ record_t Cache::prepare_record(Transaction &t)
        });
       i->last_committed_crc = final_crc;
     }
+    assert(record.deltas.back().bl.length());
   }
 
   // Transaction is now a go, set up in-memory cache state

diff --git a/src/crimson/os/seastore/onode_manager/staged-fltree/node_delta_recorder.h b/src/crimson/os/seastore/onode_manager/staged-fltree/node_delta_recorder.h
index 27df8e23a19b3b655c3682e08d247c0aa86c93ad..ea26195de71caacf8474cfa51242c2968d5067eb 100644 (file)
--- a/src/crimson/os/seastore/onode_manager/staged-fltree/node_delta_recorder.h
+++ b/src/crimson/os/seastore/onode_manager/staged-fltree/node_delta_recorder.h
@@ -29,7 +29,6 @@ class DeltaRecorder {
   }
 
   ceph::bufferlist get_delta() {
-    assert(!is_empty());
     return std::move(encoded);
   }
 

diff --git a/src/test/crimson/seastore/test_block.cc b/src/test/crimson/seastore/test_block.cc
index f3d6531bd92d93825adb39caa838333f97cc4a62..f7a39b0ef59cc25e90d782b9c7d6170441f84c14 100644 (file)
--- a/src/test/crimson/seastore/test_block.cc
+++ b/src/test/crimson/seastore/test_block.cc
@@ -22,4 +22,20 @@ void TestBlock::apply_delta(const ceph::bufferlist &bl) {
   }
 }
 
+ceph::bufferlist TestBlockPhysical::get_delta() {
+  ceph::bufferlist bl;
+  encode(delta, bl);
+  return bl;
+}
+
+void TestBlockPhysical::apply_delta_and_adjust_crc(
+    paddr_t, const ceph::bufferlist &bl) {
+  auto biter = bl.begin();
+  decltype(delta) deltas;
+  decode(deltas, biter);
+  for (auto &&d : deltas) {
+    set_contents(d.val, d.offset, d.len);
+  }
+}
+
 }

diff --git a/src/test/crimson/seastore/test_block.h b/src/test/crimson/seastore/test_block.h
index 44ec65a2375161a2fc7518b617bdb1c36a088fc7..4df99784ad40d3d31b2c494139bb05b7dced0ef8 100644 (file)
--- a/src/test/crimson/seastore/test_block.h
+++ b/src/test/crimson/seastore/test_block.h
@@ -90,7 +90,7 @@ struct TestBlockPhysical : crimson::os::seastore::CachedExtent{
 
   TestBlockPhysical(ceph::bufferptr &&ptr)
     : CachedExtent(std::move(ptr)) {}
-  TestBlockPhysical(const TestBlock &other)
+  TestBlockPhysical(const TestBlockPhysical &other)
     : CachedExtent(other) {}
 
   CachedExtentRef duplicate_for_write() final {
@@ -104,15 +104,16 @@ struct TestBlockPhysical : crimson::os::seastore::CachedExtent{
 
   void set_contents(char c, uint16_t offset, uint16_t len) {
     ::memset(get_bptr().c_str() + offset, c, len);
+    delta.push_back({c, offset, len});
   }
 
   void set_contents(char c) {
     set_contents(c, 0, get_length());
   }
 
-  ceph::bufferlist get_delta() final { return ceph::bufferlist(); }
+  ceph::bufferlist get_delta() final;
 
-  void apply_delta_and_adjust_crc(paddr_t, const ceph::bufferlist &bl) final {}
+  void apply_delta_and_adjust_crc(paddr_t, const ceph::bufferlist &bl) final;
 };
 using TestBlockPhysicalRef = TCachedExtentRef<TestBlockPhysical>;