From: Kefu Chai <kchai@redhat.com>
Date: Fri, 16 Oct 2020 14:07:50 +0000 (+0800)
Subject: crimson/common: schedule action only if the future is not available
X-Git-Tag: v16.1.0~829^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=1c422d2f2a18b9a9317cc8d548bf7f2a85664cae;p=ceph.git

crimson/common: schedule action only if the future is not available

otherwise we could call do_until() recursively if we have other tasks
which need to prempt the reactor and current future's state is actually
always available.

Signed-off-by: Kefu Chai <kchai@redhat.com>
---

diff --git a/src/crimson/common/errorator.h b/src/crimson/common/errorator.h
index a52a711f9d1b..aef57cb9b375 100644
--- a/src/crimson/common/errorator.h
+++ b/src/crimson/common/errorator.h
@@ -58,18 +58,19 @@ inline auto do_until(AsyncAction action) {
       return futurator::type::errorator_type::template make_exception_future2<>(
         f.get_exception()
       );
-    }
-    if (!f.available() || seastar::need_preempt()) {
+    } else if (f.available()) {
+      if (auto done = f.get0()) {
+        return futurator::type::errorator_type::template make_ready_future<>();
+      }
+    } else {
       return std::move(f)._then(
-        [ action = std::move(action)] (auto &&done) mutable {
-	  if (done) {
-	    return futurator::type::errorator_type::template make_ready_future<>();
-	  }
+        [action = std::move(action)] (auto &&done) mutable {
+          if (done) {
+            return futurator::type::errorator_type::template make_ready_future<>();
+          }
           return ::crimson::do_until(
-	    std::move(action));
-	});
-    } else if (bool stop_cond = f.get0()) {
-      return futurator::type::errorator_type::template make_ready_future<>();
+            std::move(action));
+        });
     }
   }
 }