From: Alex Rousskov <rousskov@measurement-factory.com>
Date: Sun, 28 Jul 2013 01:13:57 +0000 (-0600)
Subject: Removing a shared cache entry w/o slices does not count as successful purging
X-Git-Tag: SQUID_3_5_0_1~444^2~24
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5bba33c94bf702f4b10b2d90304f5e5ce749ebbb;p=thirdparty%2Fsquid.git

Removing a shared cache entry w/o slices does not count as successful purging
because all callers need a new slice, not an available anchor position.
---

diff --git a/src/ipc/StoreMap.cc b/src/ipc/StoreMap.cc
index f27364ebce..2cd1e5c118 100644
--- a/src/ipc/StoreMap.cc
+++ b/src/ipc/StoreMap.cc
@@ -356,7 +356,8 @@ Ipc::StoreMap::purgeOne()
         assert(valid(fileno));
         Anchor &s = shared->slots[fileno].anchor;
         if (s.lock.lockExclusive()) {
-            if (!s.empty()) {
+            // the caller wants a free slice; empty anchor is not enough
+            if (!s.empty() && s.start >= 0) {
                 // this entry may be marked for deletion, and that is OK
                 freeChain(fileno, s, false);
                 debugs(54, 5, "purged entry " << fileno << " from " << path);
diff --git a/src/ipc/StoreMap.h b/src/ipc/StoreMap.h
index d441c858ae..97154e63a1 100644
--- a/src/ipc/StoreMap.h
+++ b/src/ipc/StoreMap.h
@@ -180,7 +180,7 @@ public:
     /// stop writing the entry, freeing its slot for others to use if possible
     void abortWriting(const sfileno fileno);
 
-    /// finds an unlocked entry and frees it or returns false
+    /// either finds and frees an entry with at least 1 slice or returns false
     bool purgeOne();
 
     /// copies slice to its designated position