crimson/os/alienstore: submit from the alien world concurrently

Signed-off-by: Yingxin Cheng <[email protected]>

Author: cyx1231st

src/crimson/os/alienstore/alien_log.cc

@@ -17,6 +17,7 @@ CnLog::~CnLog() {
 }
 
 void CnLog::_flush(EntryVector& q, bool crash) {
+  // XXX: the waiting here will block the thread for an indeterministic peroid
   seastar::alien::submit_to(inst, shard, [&q] {
     for (auto& it : q) {
       crimson::get_logger(it.m_subsys).log(

src/crimson/os/alienstore/alien_store.cc

@@ -57,10 +57,11 @@ class OnCommit final: public Context
   }
 
   void finish(int) final {
-    return seastar::alien::submit_to(alien, cpuid, [this] {
-      alien_done.set_value();
+    std::ignore = seastar::alien::submit_to(alien, cpuid,
+        [&_alien_done=this->alien_done] {
+      _alien_done.set_value();
       return seastar::make_ready_future<>();
-    }).wait();
+    });
   }
 };
 }