os/bluestore: add a debug option to bypass block device writes for bluestore.

Signed-off-by: Igor Fedotov <ifedotov@mirantis.com>

diff --git a/src/common/config_opts.h b/src/common/config_opts.h
index be19ec68984f29c838763d879f4421fd193a9572..a1e459d4a6d21996032ba495b002c439ddf2d523 100644 (file)
--- a/src/common/config_opts.h
+++ b/src/common/config_opts.h
@@ -1071,6 +1071,7 @@ OPTION(bluestore_debug_prefill, OPT_FLOAT, 0)
 OPTION(bluestore_debug_prefragment_max, OPT_INT, 1048576)
 OPTION(bluestore_debug_inject_read_err, OPT_BOOL, false)
 OPTION(bluestore_debug_randomize_serial_transaction, OPT_INT, 0)
+OPTION(bluestore_debug_omit_block_device_write, OPT_BOOL, false)
 OPTION(bluestore_inject_wal_apply_delay, OPT_FLOAT, 0)
 OPTION(bluestore_shard_finishers, OPT_BOOL, false)
 

diff --git a/src/os/bluestore/BlueStore.cc b/src/os/bluestore/BlueStore.cc
index f96eb7bd25f0ea3ae1799961f0213da1444b4886..8e97c3c560c2b98406a36efd08c355d784d59047 100644 (file)
--- a/src/os/bluestore/BlueStore.cc
+++ b/src/os/bluestore/BlueStore.cc
@@ -6797,8 +6797,10 @@ int BlueStore::_do_wal_op(TransContext *txc, bluestore_wal_op_t& wo)
       for (auto& e : wo.extents) {
        bufferlist bl;
        p.copy(e.length, bl);
-       int r = bdev->aio_write(e.offset, bl, &txc->ioc, false);
-       assert(r == 0);
+        if (!g_conf->bluestore_debug_omit_block_device_write) {
+         int r = bdev->aio_write(e.offset, bl, &txc->ioc, false);
+         assert(r == 0);
+        }
       }
     }
     break;
@@ -7520,12 +7522,14 @@ void BlueStore::_do_write_small(
       _buffer_cache_write(txc, b, b_off, padded,
                          wctx->buffered ? 0 : Buffer::FLAG_NOCACHE);
 
-      b->get_blob().map_bl(
-       b_off, padded,
-       [&](uint64_t offset, uint64_t length, bufferlist& t) {
-         bdev->aio_write(offset, t,
-                         &txc->ioc, wctx->buffered);
-       });
+      if (!g_conf->bluestore_debug_omit_block_device_write) {
+        b->get_blob().map_bl(
+         b_off, padded,
+         [&](uint64_t offset, uint64_t length, bufferlist& t) {
+           bdev->aio_write(offset, t,
+                           &txc->ioc, wctx->buffered);
+         });
+      }
       b->dirty_blob().calc_csum(b_off, padded);
       dout(20) << __func__ << "  lex old " << *ep << dendl;
       Extent *le = o->extent_map.set_lextent(offset, b_off + head_pad, length,
@@ -7843,11 +7847,13 @@ int BlueStore::_do_alloc_write(
     }
 
     // queue io
-    b->get_blob().map_bl(
-      b_off, *l,
-      [&](uint64_t offset, uint64_t length, bufferlist& t) {
-       bdev->aio_write(offset, t, &txc->ioc, false);
-      });
+    if (!g_conf->bluestore_debug_omit_block_device_write) {
+      b->get_blob().map_bl(
+        b_off, *l,
+        [&](uint64_t offset, uint64_t length, bufferlist& t) {
+         bdev->aio_write(offset, t, &txc->ioc, false);
+        });
+    }
   }
   if (need > 0) {
     alloc->unreserve(need);