Changeset 78563 in vbox for trunk/src/VBox/Additions/WINNT/SharedFolders

Timestamp:

May 17, 2019 11:46:23 AM (6 years ago)

Author:

vboxsync

Message:

winnt/vboxsf: Investigated all the file info queries after opening a file and used TTL on the stat info to try avoid those. The TTL code needed some fixing. bugref:9172

Location:

trunk/src/VBox/Additions/WINNT/SharedFolders/driver

Files:

• info.cpp (modified) (4 diffs)
• path.cpp (modified) (2 diffs)

trunk/src/VBox/Additions/WINNT/SharedFolders/driver/info.cpp

@@ -1269 +1269 @@
                            uint8_t fTimestampsToCopyAnyway, PFILE_OBJECT pFileObj, PMRX_FCB pFcb)
 {
+    LogFlow(("vbsfNtCopyInfo: hFile=%#RX64 pVBoxFobX=%p\n", pVBoxFobX->hFile, pVBoxFobX));
+    uint64_t const nsNow = RTTimeSystemNanoTS();
+
     /*
      * Check if the size changed because RDBSS and the cache manager have
@@ -1308 +1311 @@
     }
     pVBoxFobX->Info = *pObjInfo;
+    pVBoxFobX->nsUpToDate = nsNow;
 }
 
@@ -1443 +1447 @@
          * give is "fixes".
          *
+         * The TTL here works around two issues in particular:
+         *
+         *  1. We don't want to go to the host three times during a
+         *     FileAllInformation query (RDBSS splits it up).
+         *
+         *  2. There are several filter drivers which will query info at the end of the
+         *     IRP_MJ_CREATE processing.  On a W10 guest here, FileFinder.sys (belived to
+         *     be related to the prefetcher) first queries FileStandardInformation, then
+         *     WdFilter.sys (Windows Defender) will query FileBasicInformation,
+         *     FileStandardInformation and (not relevant here) FileInternalInformation.
+         *     It would be complete waste of time to requery the data from the host for
+         *     each of the three queries.
+         *
+         * The current hardcoded 100us value was choosen by experimentation with FsPerf
+         * on a decent intel system (6700K).  This is however subject to the timer tick
+         * granularity on systems without KeQueryInterruptTimePrecise (i.e. pre win8).
+         *
          * Note! We verify the buffer size after talking to the host, assuming that there
          *       won't be a problem and saving an extra switch statement.  IIRC the
-         *       NtQueryInformationFile code verfies the sizes too.
+         *       NtQueryInformationFile code verifies the sizes too.
          */
         /** @todo r=bird: install a hack so we get FileAllInformation directly up here
@@ -1462 +1483 @@
             if (   !(pVBoxFobx->Info.Attr.fMode & RTFS_DOS_DIRECTORY) /** @todo figure out why we don't return up-to-date info for directories! */
                 && (   !pVBoxFobx->nsUpToDate
-                    || pVBoxFobx->nsUpToDate - RTTimeSystemNanoTS() < RT_NS_100US /** @todo implement proper TTL */ ) )
+                    || RTTimeSystemNanoTS() - pVBoxFobx->nsUpToDate > RT_NS_100US /** @todo implement proper TTL */ ) )
             {
                 PVBSFNTFCBEXT pVBoxFcbx = VBoxMRxGetFcbExtension(capFcb);

trunk/src/VBox/Additions/WINNT/SharedFolders/driver/path.cpp

@@ -222 +222 @@
     Log(("VBOXSF: vbsfNtCreateWorker: Calling VbglR0SfHostReqCreate(fCreate=%#RX32)...\n", pReq->CreateParms.CreateFlags));
     int vrc = VbglR0SfHostReqCreate(pNetRootExtension->map.root, pReq);
-    Log(("VBOXSF: vbsfNtCreateWorker: VbglR0SfHostReqCreate returns vrc = %Rrc, Result = 0x%x\n", vrc, pReq->CreateParms.Result));
+    Log(("VBOXSF: vbsfNtCreateWorker: VbglR0SfHostReqCreate returns vrc = %Rrc, Result = 0x%x, Handle = %#RX64\n",
+         vrc, pReq->CreateParms.Result, pReq->CreateParms.Handle));
 
     if (RT_SUCCESS(vrc))
@@ -502 +503 @@
              * Initialize our file object extension data.
              */
-            pVBoxFobx->Info     = pReq->CreateParms.Info;
-            pVBoxFobx->hFile    = pReq->CreateParms.Handle;
-            pVBoxFobx->pSrvCall = RxContext->Create.pSrvCall;
+            pVBoxFobx->Info         = pReq->CreateParms.Info;
+            pVBoxFobx->nsUpToDate   = RTTimeSystemNanoTS();
+            pVBoxFobx->hFile        = pReq->CreateParms.Handle;
+            pVBoxFobx->pSrvCall     = RxContext->Create.pSrvCall;
 
             /* bird: Dunno what this really's about. */