From c43bb8e8b5d447a936d7e14bc835f579beb0aee6 Mon Sep 17 00:00:00 2001
From: John Sully <john@csquare.ca>
Date: Fri, 12 Feb 2021 19:38:57 +0000
Subject: [PATCH] Fix deadlock in storage prefetch

Former-commit-id: 9e6162de08248f7726b97b73aee2f23808ff4e7b
---
 src/db.cpp         | 6 +++---
 src/networking.cpp | 2 +-
 src/server.h       | 2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/db.cpp b/src/db.cpp
index 14c292b6f..ee79536d6 100644
--- a/src/db.cpp
+++ b/src/db.cpp
@@ -2959,7 +2959,7 @@ int dbnumFromDb(redisDb *db)
     serverPanic("invalid database pointer");
 }
 
-void redisDbPersistentData::prefetchKeysAsync(parsed_command &command)
+void redisDbPersistentData::prefetchKeysAsync(client *c, parsed_command &command)
 {
     if (m_spstorage == nullptr)
         return;
@@ -2967,7 +2967,7 @@ void redisDbPersistentData::prefetchKeysAsync(parsed_command &command)
     AeLocker lock;
 
     std::vector<robj*> veckeys;
-    lock.arm(nullptr);
+    lock.arm(c);
     getKeysResult result = GETKEYS_RESULT_INIT;
     auto cmd = lookupCommand(szFromObj(command.argv[0]));
     int numkeys = getKeysFromCommand(cmd, command.argv, command.argc, &result);
@@ -3000,7 +3000,7 @@ void redisDbPersistentData::prefetchKeysAsync(parsed_command &command)
         vecInserts.emplace_back(sharedKey, o, std::move(spexpire));
     }
 
-    lock.arm(nullptr);
+    lock.arm(c);
     for (auto &tuple : vecInserts)
     {
         sds sharedKey = std::get<0>(tuple);
diff --git a/src/networking.cpp b/src/networking.cpp
index be50373c9..15aa6f43a 100644
--- a/src/networking.cpp
+++ b/src/networking.cpp
@@ -2362,7 +2362,7 @@ void parseClientCommandBuffer(client *c) {
         if (cqueries < c->vecqueuedcmd.size() && g_pserver->m_pstorageFactory != nullptr && !GlobalLocksAcquired()) {
             auto &query = c->vecqueuedcmd.back();
             if (query.argc > 0 && query.argc == query.argcMax) {
-                c->db->prefetchKeysAsync(query);
+                c->db->prefetchKeysAsync(c, query);
             }
         }
         c->reqtype = 0;
diff --git a/src/server.h b/src/server.h
index 7d2611c37..941770450 100644
--- a/src/server.h
+++ b/src/server.h
@@ -1136,7 +1136,7 @@ public:
     bool removeCachedValue(const char *key);
     void removeAllCachedValues();
 
-    void prefetchKeysAsync(struct parsed_command &command);
+    void prefetchKeysAsync(client *c, struct parsed_command &command);
 
     bool FSnapshot() const { return m_spdbSnapshotHOLDER != nullptr; }