rgw/cache: this commit removes indexing from ssd and redis

driver and squashes the following commits.

rgw/cache: modifications to the ssd cache driver after removing
indexing from the cache backend.
rgw/cache: modifications to redis cache driver, after
removing indexing from cache backend.
rgw/cache: modifications to policy driver code, commenting out
some pieces which refer to cache apis. Those apis have been
removed as part of modification to remove indexing from the
cache backend. These need to appropriately re-instated, once
we finalize which module will contain the data structures
related to cache policy.

Signed-off-by: Pritha Srivastava <[email protected]>

src/rgw/driver/d4n/d4n_policy.cc

@@ -214,6 +214,7 @@ int LFUDAPolicy::get_min_avg_weight() {
 }
 
 CacheBlock LFUDAPolicy::find_victim(const DoutPrefixProvider* dpp, rgw::cache::CacheDriver* cacheNode) {
+  #if 0
   std::vector<rgw::cache::Entry> entries = cacheNode->list_entries(dpp);
   std::string victimName;
   int minWeight = INT_MAX;
@@ -243,7 +244,8 @@ CacheBlock LFUDAPolicy::find_victim(const DoutPrefixProvider* dpp, rgw::cache::C
 
   if (ret < 0)
     return {};
-
+  #endif
+  CacheBlock victimBlock;
   return victimBlock;
 }
 
@@ -267,7 +269,8 @@ int LFUDAPolicy::get_block(const DoutPrefixProvider* dpp, CacheBlock* block, rgw
 
   int age = get_age();
 
-  if (cacheNode->key_exists(dpp, block->cacheObj.objName)) { /* Local copy */ 
+  bool key_exists = true; //cacheNode->key_exists(dpp, block->cacheObj.objName) //TODO- correct this
+  if (key_exists) { /* Local copy */ 
     localWeight += age;
   } else {
     std::string hosts;
@@ -371,7 +374,8 @@ uint64_t LFUDAPolicy::eviction(const DoutPrefixProvider* dpp, rgw::cache::CacheD
   int ret = cacheNode->delete_data(dpp, victim.cacheObj.objName);
 
   if (!ret) {
-    ret = set_min_avg_weight(avgWeight - (localWeight/cacheNode->get_num_entries(dpp)), ""/*local cache location*/); // Where else must this be set? -Sam
+    uint64_t num_entries = 100; //cacheNode->get_num_entries(dpp) TODO - correct this
+    ret = set_min_avg_weight(avgWeight - (localWeight/num_entries), ""/*local cache location*/); // Where else must this be set? -Sam
 
     if (!ret) {
       int age = get_age();