VBoxService,VBoxGuestLib: CPU hot plugging cleanup + review.

git-svn-id: https://www.virtualbox.org/svn/vbox/trunk@26061 cfe28804-0f27-0410-a406-dd0f0b0b656f

1 files changed, 321 insertions, 0 deletions

diff --git a/src/VBox/Additions/common/VBoxService/VBoxServiceCpuHotPlug.cpp b/src/VBox/Additions/common/VBoxService/VBoxServiceCpuHotPlug.cpp
new file mode 100644
index 00000000000..3753af0de59
--- /dev/null
+++ b/src/VBox/Additions/common/VBoxService/VBoxServiceCpuHotPlug.cpp
@@ -0,0 +1,321 @@
+/* $Id$ */
+/** @file
+ * VBoxService - Guest Additions CPU Hot Plugging Service.
+ */
+
+/*
+ * Copyright (C) 2010 Sun Microsystems, Inc.
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
+ * Clara, CA 95054 USA or visit http://www.sun.com if you need
+ * additional information or have any questions.
+ */
+
+/*******************************************************************************
+*   Header Files                                                               *
+*******************************************************************************/
+#include <iprt/assert.h>
+#include <iprt/dir.h>
+#include <iprt/file.h>
+#include <iprt/mem.h>
+#include <iprt/string.h>
+#include <iprt/thread.h>
+#include <VBox/VBoxGuestLib.h>
+#include "VBoxServiceInternal.h"
+
+#ifdef RT_OS_LINUX
+# include <iprt/linux/sysfs.h>
+# include <errno.h> /* For the sysfs API */
+#endif
+
+
+/*******************************************************************************
+*   Defined Constants And Macros                                               *
+*******************************************************************************/
+#ifdef RT_OS_LINUX
+/** @name Paths to access the CPU device
+ * @{
+ */
+# define SYSFS_ACPI_CPU_PATH    "/sys/devices/LNXSYSTM:00/device:00"
+# define SYSFS_CPU_PATH         "/sys/devices/system/cpu"
+/** @} */
+#endif
+
+
+#ifdef RT_OS_LINUX
+/**
+ * Returns the path of the ACPI CPU device with the given core and package ID.
+ *
+ * @returns VBox status code.
+ * @param   ppszPath     Where to store the path.
+ * @param   idCpuCore    The core ID of the CPU.
+ * @param   idCpuPackage The package ID of the CPU.
+ */
+static int VBoxServiceCpuHotPlugGetACPIDevicePath(char **ppszPath, uint32_t idCpuCore, uint32_t idCpuPackage)
+{
+    AssertPtr(ppszPath);
+
+    PRTDIR pDirDevices = NULL;
+    int rc = RTDirOpen(&pDirDevices, SYSFS_ACPI_CPU_PATH);  /*could use RTDirOpenFiltered*/
+    if (RT_SUCCESS(rc))
+    {
+        RTDIRENTRY DirFolderContent;
+        while (RT_SUCCESS(RTDirRead(pDirDevices, &DirFolderContent, NULL))) /* Assumption that szName has always enough space */
+        {
+            if (!strncmp(DirFolderContent.szName, "LNXCPU", 6))
+            {
+                /* Get the sysdev */
+                uint32_t idCore    = RTLinuxSysFsReadIntFile(10, "%s/%s/sysdev/topology/core_id",
+                                                             SYSFS_ACPI_CPU_PATH, DirFolderContent.szName);
+                uint32_t idPackage = RTLinuxSysFsReadIntFile(10, "%s/%s/sysdev/topology/physical_package_id",
+                                                             SYSFS_ACPI_CPU_PATH, DirFolderContent.szName);
+                if (   idCore    == idCpuCore
+                    && idPackage == idCpuPackage)
+                {
+                    /* Return the path */
+                    rc = RTStrAPrintf(ppszPath, "%s/%s", SYSFS_ACPI_CPU_PATH, DirFolderContent.szName);
+                    break;
+                }
+            }
+        }
+
+        RTDirClose(pDirDevices);
+    }
+
+    return rc;
+}
+#endif /* RT_OS_LINUX */
+
+
+/** @copydoc VBOXSERVICE::pfnPreInit */
+static DECLCALLBACK(int) VBoxServiceCpuHotPlugPreInit(void)
+{
+    return VINF_SUCCESS;
+}
+
+
+/** @copydoc VBOXSERVICE::pfnOption */
+static DECLCALLBACK(int) VBoxServiceCpuHotPlugOption(const char **ppszShort, int argc, char **argv, int *pi)
+{
+    return VINF_SUCCESS;
+}
+
+
+/** @copydoc VBOXSERVICE::pfnInit */
+static DECLCALLBACK(int) VBoxServiceCpuHotPlugInit(void)
+{
+    return VINF_SUCCESS;
+}
+
+
+/**
+ * Handles VMMDevCpuEventType_Plug.
+ *
+ * @param   idCpuCore       The CPU core ID.
+ * @param   idCpuPackage    The CPU package ID.
+ */
+static void VBoxServiceCpuHotPlugHandlePlugEvent(uint32_t idCpuCore, uint32_t idCpuPackage)
+{
+#ifdef RT_OS_LINUX
+    /*
+     * The topology directory is not available until the CPU is online. So we just iterate over all directories
+     * and enable every CPU which is not online already.
+     */
+    /** @todo Maybe use udev to monitor events from the kernel */
+    PRTDIR pDirDevices = NULL;
+    int rc = RTDirOpen(&pDirDevices, SYSFS_CPU_PATH);  /*could use RTDirOpenFiltered*/
+    if (RT_SUCCESS(rc))
+    {
+        RTDIRENTRY DirFolderContent;
+        while (RT_SUCCESS(RTDirRead(pDirDevices, &DirFolderContent, NULL))) /* Assumption that szName has always enough space */
+        {
+/** @todo r-bird: This code is bringing all CPUs online; the idCpuCore and
+ *        idCpuPackage parameters are unused!   */
+            /*
+             * Check if this is a CPU object.
+             * cpu0 is excluded because it is not possible to change the state
+             * of the first CPU on Linux (it doesn't even have an online file)
+             * and cpuidle is no CPU device. Prevents error messages later.
+             */
+            if(   !strncmp(DirFolderContent.szName, "cpu", 3)
+                && strncmp(DirFolderContent.szName, "cpu0", 4)
+                && strncmp(DirFolderContent.szName, "cpuidle", 7))
+            {
+                /* Get the sysdev */
+                RTFILE hFileCpuOnline = NIL_RTFILE;
+                rc = RTFileOpenF(&hFileCpuOnline, RTFILE_O_WRITE | RTFILE_O_OPEN | RTFILE_O_DENY_NONE,
+                                 "%s/%s/online", SYSFS_CPU_PATH, DirFolderContent.szName);
+                if (RT_SUCCESS(rc))
+                {
+                    /* Write a 1 to online the CPU */
+                    rc = RTFileWrite(hFileCpuOnline, "1", 1, NULL);
+                    RTFileClose(hFileCpuOnline);
+                    if (RT_SUCCESS(rc))
+                    {
+                        VBoxServiceVerbose(1, "CpuHotPlug: CPU %u/%u was brought online\n", idCpuPackage, idCpuCore);
+                        break;
+                    }
+                    /* Error means CPU not present or online already  */
+                }
+                else
+                    VBoxServiceError("CpuHotPlug: Failed to open \"%s/%s/online\" rc=%Rrc\n",
+                                     SYSFS_CPU_PATH, DirFolderContent.szName, rc);
+            }
+        }
+    }
+    else
+        VBoxServiceError("CpuHotPlug: Failed to open path %s rc=%Rrc\n", SYSFS_CPU_PATH, rc);
+#else
+# error "Port me"
+#endif
+}
+
+
+/**
+ * Handles VMMDevCpuEventType_Unplug.
+ *
+ * @param   idCpuCore       The CPU core ID.
+ * @param   idCpuPackage    The CPU package ID.
+ */
+static void VBoxServiceCpuHotPlugHandleUnplugEvent(uint32_t idCpuCore, uint32_t idCpuPackage)
+{
+#ifdef RT_OS_LINUX
+    char *pszCpuDevicePath = NULL;
+    int rc = VBoxServiceCpuHotPlugGetACPIDevicePath(&pszCpuDevicePath, idCpuCore, idCpuPackage);
+    if (RT_SUCCESS(rc))
+    {
+        RTFILE hFileCpuEject;
+        rc = RTFileOpenF(&hFileCpuEject, RTFILE_O_WRITE | RTFILE_O_OPEN | RTFILE_O_DENY_NONE,
+                         "%s/eject", pszCpuDevicePath);
+        if (RT_SUCCESS(rc))
+        {
+            /* Write a 1 to eject the CPU */
+            rc = RTFileWrite(hFileCpuEject, "1", 1, NULL);
+            if (RT_SUCCESS(rc))
+                VBoxServiceVerbose(1, "CpuHotPlug: CPU %u/%u was ejected\n", idCpuPackage, idCpuCore);
+            else
+                VBoxServiceError("CpuHotPlug: Failed to eject CPU %u/%u rc=%Rrc\n", idCpuPackage, idCpuCore, rc);
+
+            RTFileClose(hFileCpuEject);
+        }
+        else
+            VBoxServiceError("CpuHotPlug: Failed to open \"%s/eject\" rc=%Rrc\n", pszCpuDevicePath, rc);
+        RTStrFree(pszCpuDevicePath);
+    }
+    else
+        VBoxServiceError("CpuHotPlug: Failed to get CPU device path rc=%Rrc\n", rc);
+#else
+# error "Port me"
+#endif
+}
+
+
+/** @copydoc VBOXSERVICE::pfnWorker */
+DECLCALLBACK(int) VBoxServiceCpuHotPlugWorker(bool volatile *pfShutdown)
+{
+    /*
+     * Tell the control thread that it can continue spawning services.
+     */
+    RTThreadUserSignal(RTThreadSelf());
+
+    /*
+     * Enable the CPU hotplug notifier.
+     */
+    int rc = VbglR3CpuHotPlugInit();
+    if (RT_FAILURE(rc))
+        return rc;
+
+    /*
+     * The Work Loop.
+     */
+    for (;;)
+    {
+        /* Wait for CPU hot plugging event. */
+        uint32_t            idCpuCore;
+        uint32_t            idCpuPackage;
+        VMMDevCpuEventType  enmEventType;
+        rc = VbglR3CpuHotPlugWaitForEvent(&enmEventType, &idCpuCore, &idCpuPackage);
+        if (RT_SUCCESS(rc))
+        {
+            VBoxServiceVerbose(3, "CpuHotPlug: Event happened idCpuCore=%u idCpuPackage=%u enmEventType=%d\n",
+                               idCpuCore, idCpuPackage, enmEventType);
+            switch (enmEventType)
+            {
+                case VMMDevCpuEventType_Plug:
+                    VBoxServiceCpuHotPlugHandlePlugEvent(idCpuCore, idCpuPackage);
+                    break;
+
+                case VMMDevCpuEventType_Unplug:
+                    VBoxServiceCpuHotPlugHandleUnplugEvent(idCpuCore, idCpuPackage);
+                    break;
+
+                default:
+                {
+                    static uint32_t s_iErrors = 0;
+                    if (s_iErrors++ < 10)
+                        VBoxServiceError("CpuHotPlug: Unknown event: idCpuCore=%u idCpuPackage=%u enmEventType=%d\n",
+                                         idCpuCore, idCpuPackage, enmEventType);
+                    break;
+                }
+            }
+        }
+        else if (rc != VERR_INTERRUPTED && rc != VERR_TRY_AGAIN)
+        {
+            VBoxServiceError("CpuHotPlug: VbglR3CpuHotPlugWaitForEvent returned %Rrc\n", rc);
+            break;
+        }
+
+        if (*pfShutdown)
+            break;
+    }
+
+    VbglR3CpuHotPlugTerm();
+    return rc;
+}
+
+
+/** @copydoc VBOXSERVICE::pfnStop */
+static DECLCALLBACK(void) VBoxServiceCpuHotPlugStop(void)
+{
+    VbglR3InterruptEventWaits();
+    return;
+}
+
+
+/** @copydoc VBOXSERVICE::pfnTerm */
+static DECLCALLBACK(void) VBoxServiceCpuHotPlugTerm(void)
+{
+    return;
+}
+
+
+/**
+ * The 'timesync' service description.
+ */
+VBOXSERVICE g_CpuHotPlug =
+{
+    /* pszName. */
+    "cpuhotplug",
+    /* pszDescription. */
+    "CPU hot plugging monitor",
+    /* pszUsage. */
+    NULL,
+    /* pszOptions. */
+    NULL,
+    /* methods */
+    VBoxServiceCpuHotPlugPreInit,
+    VBoxServiceCpuHotPlugOption,
+    VBoxServiceCpuHotPlugInit,
+    VBoxServiceCpuHotPlugWorker,
+    VBoxServiceCpuHotPlugStop,
+    VBoxServiceCpuHotPlugTerm
+};
+