From: Haomai Wang <haomaiwang@gmail.com>
Date: Wed, 27 May 2015 02:48:47 +0000 (+0800)
Subject: Event: Avoid potential wakeup leak between set and read
X-Git-Tag: v9.0.2~23^2~11
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=a14b0e147060337200fba78e90d25a4835aaae76;p=ceph.git

Event: Avoid potential wakeup leak between set and read

Signed-off-by: Haomai Wang <haomaiwang@gmail.com>
---

diff --git a/src/msg/async/Event.cc b/src/msg/async/Event.cc
index 4b63209078f0..131d86924ed2 100644
--- a/src/msg/async/Event.cc
+++ b/src/msg/async/Event.cc
@@ -46,9 +46,10 @@ class C_handle_notify : public EventCallback {
   C_handle_notify(EventCenter *c): center(c) {}
   void do_request(int fd_or_id) {
     char c[256];
-    center->already_wakeup.set(0);
-    int r = read(fd_or_id, c, sizeof(c));
-    assert(r > 0);
+    do {
+      center->already_wakeup.set(0);
+      read(fd_or_id, c, sizeof(c));
+    } while (center->already_wakeup.read());
   }
 };