Changeset 86177 in vbox for trunk/src/VBox/Runtime/r0drv/nt/mp-r0drv-nt.cpp

Timestamp:

Sep 19, 2020 4:06:57 PM (4 years ago)

Author:

vboxsync

Message:

Revert r140428 for now (Runtime/mp-r0drv-nt.cpp: Dynamically determine the size of the KAFFINITY_EX structure as it is not static across Windows versions (increased lately with W10 20H2) )

File:

• trunk/src/VBox/Runtime/r0drv/nt/mp-r0drv-nt.cpp (modified) (4 diffs)

trunk/src/VBox/Runtime/r0drv/nt/mp-r0drv-nt.cpp

@@ -37 +37 @@
 #include <iprt/log.h>
 #include <iprt/mem.h>
-#include <iprt/string.h>
 #include <iprt/time.h>
 #include "r0drv/mp-r0drv.h"
@@ -123 +122 @@
 /** The handle of the rtR0NtMpProcessorChangeCallback registration. */
 static PVOID                            g_pvMpCpuChangeCallback = NULL;
-/** Size of the KAFFINITY_EX structure.
- * This increased from 20 to 32 bitmap words in the 2020 H2 windows 10 release
- * (i.e. 1280 to 2048 CPUs).  We expect this to increase in the future. */
-static size_t                           g_cbRtMpNtKaffinityEx = RT_UOFFSETOF(KAFFINITY_EX, Bitmap)
-                                                              + RT_SIZEOFMEMB(KAFFINITY_EX, Bitmap[0]) * 256;
-/** The size value of the KAFFINITY_EX structure. */
-static uint16_t                         g_cRtMpNtKaffinityExEntries = 256;
 
 
@@ -606 +598 @@
         && g_pfnrtKeGetProcessorIndexFromNumber)
     {
-        /* Determine the real size of the KAFFINITY_EX structure. */
-        union
-        {
-            KAFFINITY_EX Struct;
-            uint8_t      ab[_4K + 8]; /* This should suffice for determining the real size. */
-        } u;
-        RT_ZERO(u);
-        size_t const cMaxEntries = (sizeof(u) - RT_UOFFSETOF(KAFFINITY_EX, Bitmap[0])) / sizeof(u.Struct.Bitmap[0]);
-        g_pfnrtKeInitializeAffinityEx(&u.Struct);
-        if (u.Struct.Size > 1 && u.Struct.Size <= cMaxEntries)
-        {
-            g_cRtMpNtKaffinityExEntries = u.Struct.Size;
-            g_cbRtMpNtKaffinityEx       = u.Struct.Size * sizeof(u.Struct.Bitmap[0]) + RT_UOFFSETOF(KAFFINITY_EX, Bitmap[0]);
-            g_pfnrtMpPokeCpuWorker      = rtMpPokeCpuUsingHalRequestIpiW7Plus;
-            DbgPrint("IPRT: RTMpPoke => rtMpPokeCpuUsingHalRequestIpiW7Plus\n");
-            return VINF_SUCCESS;
-        }
-        DbgPrint("IPRT: RTMpPoke can't use rtMpPokeCpuUsingHalRequestIpiW7Plus! u.Struct.Size=%u\n", u.Struct.Size);
-        AssertReleaseMsg(u.Struct.Size <= cMaxEntries, ("%#x\n", u.Struct.Size)); /* stack is toast if larger (32768 CPUs). */
-    }
-
-    if (pOsVerInfo->uMajorVer >= 6 && g_pfnrtKeIpiGenericCall)
+        g_pfnrtMpPokeCpuWorker = rtMpPokeCpuUsingHalRequestIpiW7Plus;
+        DbgPrint("IPRT: RTMpPoke => rtMpPokeCpuUsingHalRequestIpiW7Plus\n");
+    }
+    else if (pOsVerInfo->uMajorVer >= 6 && g_pfnrtKeIpiGenericCall)
     {
         DbgPrint("IPRT: RTMpPoke => rtMpPokeCpuUsingBroadcastIpi\n");
@@ -1887 +1861 @@
 {
     /* idCpu is an HAL processor index, so we can use it directly. */
-    PKAFFINITY_EX pTarget = (PKAFFINITY_EX)alloca(g_cbRtMpNtKaffinityEx);
-    pTarget->Size = g_cRtMpNtKaffinityExEntries; /* (just in case KeInitializeAffinityEx starts using it) */
-    g_pfnrtKeInitializeAffinityEx(pTarget);
-    g_pfnrtKeAddProcessorAffinityEx(pTarget, idCpu);
-
-    g_pfnrtHalRequestIpiW7Plus(0, pTarget);
+    KAFFINITY_EX Target;
+    g_pfnrtKeInitializeAffinityEx(&Target);
+    g_pfnrtKeAddProcessorAffinityEx(&Target, idCpu);
+
+    g_pfnrtHalRequestIpiW7Plus(0, &Target);
     return VINF_SUCCESS;
 }