From: Or Friedmann <ofriedma@redhat.com>
Date: Wed, 24 Jun 2020 12:55:20 +0000 (+0300)
Subject: rgw: add negative cache to the system object
X-Git-Tag: v16.1.0~1708^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=0900bd8cf90babd6fafcb398854a4ddb071a27ee;p=ceph.git

rgw: add negative cache to the system object

add negative cache to the system object

Signed-off-by: Or Friedmann <ofriedma@redhat.com>

Fixes: https://tracker.ceph.com/issues/45816
---

diff --git a/src/rgw/rgw_cache.cc b/src/rgw/rgw_cache.cc
index 41dd004c10f89..90a608d1bf159 100644
--- a/src/rgw/rgw_cache.cc
+++ b/src/rgw/rgw_cache.cc
@@ -67,6 +67,11 @@ int ObjectCache::get(const string& name, ObjectCacheInfo& info, uint32_t mask, r
   }
 
   ObjectCacheInfo& src = iter->second.info;
+  if(src.status == -ENOENT) {
+    ldout(cct, 10) << "cache get: name=" << name << " : hit (negative entry)" << dendl;
+    if (perfcounter) perfcounter->inc(l_rgw_cache_hit);
+    return -ENODATA;
+  }
   if ((src.flags & mask) != mask) {
     ldout(cct, 10) << "cache get: name=" << name << " : type miss (requested=0x"
                    << std::hex << mask << ", cached=0x" << src.flags
diff --git a/src/rgw/services/svc_sys_obj_cache.cc b/src/rgw/services/svc_sys_obj_cache.cc
index 8df76c85b5924..04a958cd051a8 100644
--- a/src/rgw/services/svc_sys_obj_cache.cc
+++ b/src/rgw/services/svc_sys_obj_cache.cc
@@ -132,8 +132,9 @@ int RGWSI_SysObj_Cache::read(RGWSysObjectCtxBase& obj_ctx,
     flags |= CACHE_FLAG_OBJV;
   if (attrs)
     flags |= CACHE_FLAG_XATTRS;
-
-  if ((cache.get(name, info, flags, cache_info) == 0) &&
+  
+  int r = cache.get(name, info, flags, cache_info);
+  if (r == 0 &&
       (!refresh_version || !info.version.compare(&(*refresh_version)))) {
     if (info.status < 0)
       return info.status;
@@ -156,9 +157,11 @@ int RGWSI_SysObj_Cache::read(RGWSysObjectCtxBase& obj_ctx,
     }
     return obl->length();
   }
+  if(r == -ENODATA)
+    return -ENOENT;
 
   map<string, bufferlist> unfiltered_attrset;
-  int r = RGWSI_SysObj_Core::read(obj_ctx, read_state, objv_tracker,
+  r = RGWSI_SysObj_Core::read(obj_ctx, read_state, objv_tracker,
                          obj, obl, ofs, end,
 			 (attrs ? &unfiltered_attrset : nullptr),
 			 true, /* cache unfiltered attrs */
@@ -215,7 +218,8 @@ int RGWSI_SysObj_Cache::get_attr(const rgw_raw_obj& obj,
 
   uint32_t flags = CACHE_FLAG_XATTRS;
 
-  if (cache.get(name, info, flags, nullptr) == 0) {
+  int r = cache.get(name, info, flags, nullptr);
+  if (r == 0) {
     if (info.status < 0)
       return info.status;
 
@@ -226,6 +230,8 @@ int RGWSI_SysObj_Cache::get_attr(const rgw_raw_obj& obj,
 
     *dest = iter->second;
     return dest->length();
+  } else if (r == -ENODATA) {
+    return -ENOENT;
   }
   /* don't try to cache this one */
   return RGWSI_SysObj_Core::get_attr(obj, attr_name, dest, y);
@@ -382,6 +388,9 @@ int RGWSI_SysObj_Cache::raw_stat(const rgw_raw_obj& obj, uint64_t *psize, real_t
       objv_tracker->read_version = info.version;
     goto done;
   }
+  if (r == -ENODATA) {
+    return -ENOENT;
+  }
   r = RGWSI_SysObj_Core::raw_stat(obj, &size, &mtime, &epoch, &info.xattrs,
                                   first_chunk, objv_tracker, y);
   if (r < 0) {