From: cfanz <songxinyingftd@gmail.com>
Date: Wed, 2 May 2018 07:07:50 +0000 (+0800)
Subject: rgw: avoid race condition in RGWHTTPClient::wait()
X-Git-Tag: v14.1.0~1025^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=refs%2Fpull%2F21767%2Fhead;p=ceph.git

rgw: avoid race condition in RGWHTTPClient::wait()

The cond is signaled in RGWHTTPManager's thread, which is
different with the thread executing wait(), so there is a
race condition.

Signed-off-by: cfanz <songxinyingftd@gmail.com>
---

diff --git a/src/rgw/rgw_http_client.cc b/src/rgw/rgw_http_client.cc
index 25c63a7794db..2e9ac8da6f02 100644
--- a/src/rgw/rgw_http_client.cc
+++ b/src/rgw/rgw_http_client.cc
@@ -51,6 +51,9 @@ struct rgw_http_req_data : public RefCountedObject {
 
   int wait() {
     Mutex::Locker l(lock);
+    if (done) {
+      return ret;
+    }
     cond.Wait(lock);
     return ret;
   }
@@ -524,11 +527,7 @@ bool RGWHTTPClient::is_done()
  */
 int RGWHTTPClient::wait()
 {
-  if (!req_data->is_done()) {
-    return req_data->wait();
-  }
-
-  return req_data->ret;
+  return req_data->wait();
 }
 
 RGWHTTPClient::~RGWHTTPClient()