From: Sage Weil <sage@inktank.com>
Date: Mon, 3 Feb 2014 19:44:18 +0000 (-0800)
Subject: osd/ReplicatedPG: ignore starvation potential when taking write lock during promote
X-Git-Tag: v0.78~166^2~13
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=6581ce9cf82647d5198b8db26c08d5f3a43de2e9;p=ceph.git

osd/ReplicatedPG: ignore starvation potential when taking write lock during promote

Signed-off-by: Sage Weil <sage@inktank.com>
---

diff --git a/src/osd/ReplicatedPG.cc b/src/osd/ReplicatedPG.cc
index ad1d2cfa73c..8e958c5bce9 100644
--- a/src/osd/ReplicatedPG.cc
+++ b/src/osd/ReplicatedPG.cc
@@ -5596,8 +5596,8 @@ void ReplicatedPG::finish_promote(int r, OpRequestRef op,
   tctx->new_snapset.head_exists = true;
   dout(20) << __func__ << " new_snapset " << tctx->new_snapset << dendl;
 
-  // take RWWRITE lock for duration of our local write
-  if (!obc->rwstate.get_write_lock()) {
+  // take RWWRITE lock for duration of our local write.  ignore starvation.
+  if (!obc->rwstate.take_write_lock()) {
     assert(0 == "problem!");
   }
   tctx->lock_to_release = OpContext::W_LOCK;
diff --git a/src/osd/osd_types.h b/src/osd/osd_types.h
index 8360218790d..8c1b49106af 100644
--- a/src/osd/osd_types.h
+++ b/src/osd/osd_types.h
@@ -2549,6 +2549,14 @@ public:
 	return false;
       }
     }
+    /// same as get_write_lock, but ignore starvation
+    bool take_write_lock() {
+      if (state == RWWRITE) {
+	count++;
+	return true;
+      }
+      return get_write_lock();
+    }
     void dec(list<OpRequestRef> *requeue) {
       assert(count > 0);
       assert(requeue);