Changeset 83101 in vbox for trunk/src/VBox/Runtime/r3

Timestamp:

Feb 17, 2020 7:46:52 PM (5 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

136162

Message:

IPRT: Simple TLS destructor implementation for windows.

Location:

trunk/src/VBox/Runtime/r3/win

Files:

• dllmain-win.cpp (modified) (1 diff)
• tls-dllmain-win.cpp (copied) (copied from trunk/src/VBox/Runtime/r3/win/tls-win.cpp ) (4 diffs)

trunk/src/VBox/Runtime/r3/win/dllmain-win.cpp

@@ -82 +82 @@
 
         case DLL_THREAD_DETACH:
+            rtTlsWinDetachThread();
             rtThreadNativeDetach();
             break;

trunk/src/VBox/Runtime/r3/win/tls-dllmain-win.cpp

@@ -33 +33 @@
 
 #include <iprt/thread.h>
+#include <iprt/assert.h>
+#include <iprt/critsect.h>
+#include <iprt/errcore.h>
 #include <iprt/log.h>
-#include <iprt/assert.h>
-#include <iprt/errcore.h>
+#include <iprt/mem.h>
+#include <iprt/once.h>
 #include "internal/thread.h"
 
 
-AssertCompile(sizeof(RTTLS) >= sizeof(DWORD));
+/*********************************************************************************************************************************
+*   Structures and Typedefs                                                                                                      *
+*********************************************************************************************************************************/
+typedef struct RTTLSWINDTOR
+{
+    RTLISTNODE      ListEntry;
+    DWORD           iTls;
+    PFNRTTLSDTOR    pfnDestructor;
+} RTTLSWINDTOR;
+typedef RTTLSWINDTOR *PRTTLSWINDTOR;
+
+
+/*********************************************************************************************************************************
+*   Global Variables                                                                                                             *
+*********************************************************************************************************************************/
+/** Init once for the list and critical section. */
+static RTONCE               g_Once = RTONCE_INITIALIZER;
+/** Critical section protecting the TLS destructor list. */
+static RTCRITSECTRW         g_CritSect;
+/** List of TLS destrictors (RTTLSWINDTOR).  */
+static RTLISTANCHOR         g_TlsDtorHead;
+/** Number of desturctors in the list (helps putting of initialization). */
+static uint32_t volatile    g_cTlsDtors = 0;
+
+
+/**
+ * @callback_method_impl{FNRTONCE}
+ */
+static DECLCALLBACK(int32_t) rtTlsWinInitLock(void *pvUser)
+{
+    RT_NOREF(pvUser);
+    RTListInit(&g_TlsDtorHead);
+    return RTCritSectRwInit(&g_CritSect);
+}
 
 
 RTR3DECL(RTTLS) RTTlsAlloc(void)
 {
+    AssertCompile(sizeof(RTTLS) >= sizeof(DWORD));
     DWORD iTls = TlsAlloc();
     return iTls != TLS_OUT_OF_INDEXES ? (RTTLS)iTls : NIL_RTTLS;
@@ -51 +88 @@
 RTR3DECL(int) RTTlsAllocEx(PRTTLS piTls, PFNRTTLSDTOR pfnDestructor)
 {
-    AssertReturn(!pfnDestructor, VERR_NOT_SUPPORTED);
-    DWORD iTls = TlsAlloc();
-    if (iTls != TLS_OUT_OF_INDEXES)
-    {
-        Assert((RTTLS)iTls != NIL_RTTLS);
-        *piTls = (RTTLS)iTls;
-        Assert((DWORD)*piTls == iTls);
-        return VINF_SUCCESS;
-    }
-
-    return VERR_NO_MEMORY;
+    int rc;
+    if (!pfnDestructor)
+    {
+        DWORD iTls = TlsAlloc();
+        if (iTls != TLS_OUT_OF_INDEXES)
+        {
+            Assert((RTTLS)iTls != NIL_RTTLS);
+            *piTls = (RTTLS)iTls;
+            Assert((DWORD)*piTls == iTls);
+            rc = VINF_SUCCESS;
+        }
+        else
+            rc = VERR_NO_MEMORY;
+    }
+    else
+    {
+        rc = RTOnce(&g_Once, rtTlsWinInitLock, NULL);
+        if (RT_SUCCESS(rc))
+        {
+            PRTTLSWINDTOR pDtor = (PRTTLSWINDTOR)RTMemAlloc(sizeof(*pDtor));
+            if (pDtor)
+            {
+                DWORD iTls = TlsAlloc();
+                if (iTls != TLS_OUT_OF_INDEXES)
+                {
+                    Assert((RTTLS)iTls != NIL_RTTLS);
+                    *piTls = (RTTLS)iTls;
+                    Assert((DWORD)*piTls == iTls);
+
+                    /*
+                     * Add the destructor to the list.  We keep it sorted.
+                     */
+                    pDtor->iTls = iTls;
+                    pDtor->pfnDestructor = pfnDestructor;
+                    RTCritSectRwEnterExcl(&g_CritSect);
+                    RTListAppend(&g_TlsDtorHead, &pDtor->ListEntry);
+                    ASMAtomicIncU32(&g_cTlsDtors);
+                    RTCritSectRwLeaveExcl(&g_CritSect);
+
+                    rc = VINF_SUCCESS;
+                }
+                else
+                    rc = VERR_NO_MEMORY;
+            }
+            else
+                rc = VERR_NO_MEMORY;
+        }
+    }
+    return rc;
 }
 
@@ -70 +145 @@
         return VINF_SUCCESS;
     if (TlsFree((DWORD)iTls))
-        return VINF_SUCCESS;
+    {
+        if (ASMAtomicReadU32(&g_cTlsDtors) > 0)
+        {
+            RTCritSectRwEnterExcl(&g_CritSect);
+            PRTTLSWINDTOR pDtor;
+            RTListForEach(&g_TlsDtorHead, pDtor, RTTLSWINDTOR, ListEntry)
+            {
+                if (pDtor->iTls == (DWORD)iTls)
+                {
+                    RTListNodeRemove(&pDtor->ListEntry);
+                    ASMAtomicDecU32(&g_cTlsDtors);
+                    RTMemFree(pDtor);
+                    break;
+                }
+            }
+            RTCritSectRwLeaveExcl(&g_CritSect);
+        }
+        return VINF_SUCCESS;
+    }
     return RTErrConvertFromWin32(GetLastError());
 }
@@ -103 +196 @@
 }
 
+
+/**
+ * Called by dllmain-win.cpp when a thread detaches.
+ */
+DECLHIDDEN(void) rtTlsWinDetachThread(void)
+{
+    if (ASMAtomicReadU32(&g_cTlsDtors) > 0)
+    {
+        RTCritSectRwEnterShared(&g_CritSect);
+        PRTTLSWINDTOR pDtor;
+        RTListForEach(&g_TlsDtorHead, pDtor, RTTLSWINDTOR, ListEntry)
+        {
+            void *pvValue = TlsGetValue(pDtor->iTls);
+            if (pvValue != NULL)
+            {
+                pDtor->pfnDestructor(pvValue);
+                TlsSetValue(pDtor->iTls, NULL);
+            }
+        }
+        RTCritSectRwLeaveShared(&g_CritSect);
+    }
+}
+