r0drv/solaris/threadctxhooks-r0drv-solaris.c

	threadctxhooks-r0drv-solaris.c revision 6b83e14a3fd9389cfed4aa0790485adbca556e1a
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync/* $Id$ */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync/** @file
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * IPRT - Thread-Context Hook, Ring-0 Driver, Solaris.
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync/*
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * Copyright (C) 2013 Oracle Corporation
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync *
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * This file is part of VirtualBox Open Source Edition (OSE), as
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * available from http://www.virtualbox.org. This file is free software;
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * you can redistribute it and/or modify it under the terms of the GNU
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * General Public License (GPL) as published by the Free Software
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * Foundation, in version 2 as it comes in the "COPYING" file of the
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync *
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * The contents of this file may alternatively be used under the terms
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * of the Common Development and Distribution License Version 1.0
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * VirtualBox OSE distribution, in which case the provisions of the
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * CDDL are applicable instead of those of the GPL.
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync *
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * You may elect to license modified versions of this file under the
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * terms and conditions of either the GPL or the CDDL or both.
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync/*******************************************************************************
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync*   Header Files                                                               *
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync*******************************************************************************/
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync#include "the-solaris-kernel.h"
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync#include "internal/iprt.h"
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync#include <iprt/mem.h>
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync#include <iprt/assert.h>
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync#include <iprt/thread.h>
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync#include <iprt/err.h>
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync#include <iprt/asm.h>
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync#include "internal/thread.h"
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync/*******************************************************************************
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync*   Structures and Typedefs                                                    *
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync*******************************************************************************/
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync/**
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * The internal thread-context object.
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsynctypedef struct RTTHREADCTXINT
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync{
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    /** Magic value (RTTHREADCTXINT_MAGIC). */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    uint32_t volatile           u32Magic;
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    /** The thread handle (owner) for which the context-hooks are registered. */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    RTNATIVETHREAD              hOwner;
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    /** Pointer to the registered thread-context hook. */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    PFNRTTHREADCTXHOOK          pfnThreadCtxHook;
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    /** User argument passed to the thread-context hook. */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    void                       *pvUser;
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    /** Whether this handle has any hooks registered or not. */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    bool                        fRegistered;
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    /** Number of references to this object. */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    uint32_t volatile           cRefs;
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync} RTTHREADCTXINT, *PRTTHREADCTXINT;
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync/*******************************************************************************
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync*   Defined Constants And Macros                                               *
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync*******************************************************************************/
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync/** Validates a thread-context hook handle and returns rc if not valid. */
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync#define RTTHREADCTX_VALID_RETURN_RC(pThis, rc) \
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    do { \
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync        AssertPtrReturn((pThis), (rc)); \
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync        AssertReturn((pThis)->u32Magic == RTTHREADCTXINT_MAGIC, (rc)); \
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync        AssertReturn((pThis)->cRefs > 0, (rc)); \
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync    } while (0)
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync/**
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync * Hook function for the thread-preempting event.
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync *
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync * @param   pvThreadCtxInt  Opaque pointer to the internal thread-context
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync *                          object.
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync *
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * @remarks Called with the with preemption disabled!
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync */
4a4140b851e27d435a9c56675db3598b8490fea2vboxsyncstatic void rtThreadCtxHooksSolPreempting(void *pvThreadCtxInt)
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync{
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    PRTTHREADCTXINT pThis = (PRTTHREADCTXINT)pvThreadCtxInt;
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    AssertPtr(pThis);
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    Assert(!RTThreadPreemptIsEnabled(NIL_RTTHREAD));
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync    if (pThis->fRegistered)
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    {
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync        Assert(pThis->pfnThreadCtxHook);
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync        pThis->pfnThreadCtxHook(RTTHREADCTXEVENT_PREEMPTING, pThis->pvUser);
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync    }
4a4140b851e27d435a9c56675db3598b8490fea2vboxsync}
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync/**
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * Hook function for the thread-resumed event.
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync *
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync * @param   pvThreadCtxInt  Opaque pointer to the internal thread-context
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync *                          object.
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync */
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsyncstatic void rtThreadCtxHooksSolResumed(void *pvThreadCtxInt)
3cc33d1e7558a0f4a04b59bfe914a24d0b9a2329vboxsync{
    PRTTHREADCTXINT pThis = (PRTTHREADCTXINT)pvThreadCtxInt;
    AssertPtr(pThis);
    Assert(!RTThreadPreemptIsEnabled(NIL_RTTHREAD));

    if (pThis->fRegistered)
    {
        Assert(pThis->pfnThreadCtxHook);
        pThis->pfnThreadCtxHook(RTTHREADCTXEVENT_RESUMED, pThis->pvUser);
    }
}


/**
 * Hook function for the thread-free event.
 *
 * @param   pvThreadCtxInt      Opaque pointer to the internal thread-context
 *                              object.
 * @param   fIsExec             Whether this event is triggered due to exec().
 */
static void rtThreadCtxHooksSolFree(void *pvThreadCtxInt, int fIsExec)
{
    PRTTHREADCTXINT pThis = (PRTTHREADCTXINT)pvThreadCtxInt;
    AssertPtrReturnVoid(pThis);
    AssertMsgReturnVoid(pThis->u32Magic == RTTHREADCTXINT_MAGIC, ("pThis->u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis));

    uint32_t cRefs = ASMAtomicReadU32(&pThis->cRefs);
    if (RT_UNLIKELY(!cRefs))
    {
        /* Should never happen. */
        AssertMsgFailed(("rtThreadCtxHooksSolFree with cRefs=0 pThis=%p\n", pThis));
        return;
    }

    cRefs = ASMAtomicDecU32(&pThis->cRefs)
    if (!cRefs)
    {
        Assert(!pThis->fRegistered);
        ASMAtomicWriteU32(&pThis->u32Magic, ~RTTHREADCTXINT_MAGIC);
        RTMemFree(pThis);
    }
}


RTDECL(int) RTThreadCtxHooksCreate(PRTTHREADCTX phThreadCtx)
{
    PRTTHREADCTXINT pThis;
    Assert(RTThreadPreemptIsEnabled(NIL_RTTHREAD));

    pThis = (PRTTHREADCTXINT)RTMemAllocZ(sizeof(*pThis));
    if (RT_UNLIKELY(!pThis))
        return VERR_NO_MEMORY;
    pThis->u32Magic    = RTTHREADCTXINT_MAGIC;
    pThis->hOwner      = RTThreadNativeSelf();
    pThis->fRegistered = false;
    pThis->cRefs       = 2;               /* One reference for the thread, one for the hook object. */

    /*
     * installctx() allocates memory and thus cannot be used in RTThreadCtxHooksRegister() which can be used
     * with preemption disabled. We allocate the context-hooks here and use 'fRegistered' to determine if we can
     * invoke the consumer's hook or not.
     */
    if (g_frtSolOldThreadCtx)
    {
        g_rtSolThreadCtx.Install.pfnSol_installctx_old(curthread,
                                                       pThis,
                                                       rtThreadCtxHooksSolPreempting,
                                                       rtThreadCtxHooksSolResumed,
                                                       NULL,                          /* fork */
                                                       NULL,                          /* lwp_create */
                                                       rtThreadCtxHooksSolFree);
    }
    else
    {
        g_rtSolThreadCtx.Install.pfnSol_installctx(curthread,
                                                   pThis,
                                                   rtThreadCtxHooksSolPreempting,
                                                   rtThreadCtxHooksSolResumed,
                                                   NULL,                              /* fork */
                                                   NULL,                              /* lwp_create */
                                                   NULL,                              /* exit */
                                                   rtThreadCtxHooksSolFree);
    }

    *phThreadCtx = pThis;
    return VINF_SUCCESS;
}


RTDECL(uint32_t) RTThreadCtxHooksRetain(RTTHREADCTX hThreadCtx)
{
    PRTTHREADCTXINT pThis = hThreadCtx;
    RTTHREADCTX_VALID_RETURN_RC(hThreadCtx, UINT32_MAX);

    uint32_t cRefs = ASMAtomicIncU32(&pThis->cRefs);
    Assert(cRefs < UINT32_MAX / 2);
    return cRefs;
}


RTDECL(uint32_t) RTThreadCtxHooksRelease(RTTHREADCTX hThreadCtx)
{
    PRTTHREADCTXINT pThis = hThreadCtx;
    if (pThis == NIL_RTTHREADCTX)
        return 0;

    RTTHREADCTX_VALID_RETURN_RC(hThreadCtx, UINT32_MAX);
    Assert(RTThreadPreemptIsEnabled(NIL_RTTHREAD));

    pThis->fRegistered = false;
    uint32_t cRefs = ASMAtomicDecU32(&pThis->cRefs);

    if (   pThis->hOwner == RTThreadNativeSelf()
        && cRefs == 1)
    {
        /*
         * removectx() will invoke rtThreadCtxHooksSolFree() and there is no way to bypass it and still use
         * rtThreadCtxHooksSolFree() at the same time.  Hence the convulated reference counting.
         *
         * When this function is called from the owner thread and is the last reference, we call removectx() which
         * will invoke rtThreadCtxHooksSolFree() with cRefs = 1 and that will then free the hook object.
         *
         * When the function is called from a different thread, we simply decrement the reference. Whenever the
         * ring-0 thread dies, Solaris will call rtThreadCtxHooksSolFree() which will free the hook object.
         */
        int rc;
        if (g_frtSolOldThreadCtx)
        {
            rc = g_rtSolThreadCtx.Remove.pfnSol_removectx_old(curthread,
                                                              pThis,
                                                              rtThreadCtxHooksSolPreempting,
                                                              rtThreadCtxHooksSolResumed,
                                                              NULL,                          /* fork */
                                                              NULL,                          /* lwp_create */
                                                              rtThreadCtxHooksSolFree);
        }
        else
        {
            rc = g_rtSolThreadCtx.Remove.pfnSol_removectx(curthread,
                                                          pThis,
                                                          rtThreadCtxHooksSolPreempting,
                                                          rtThreadCtxHooksSolResumed,
                                                          NULL,                              /* fork */
                                                          NULL,                              /* lwp_create */
                                                          NULL,                              /* exit */
                                                          rtThreadCtxHooksSolFree);
        }
        AssertMsg(rc, ("removectx failed. rc=%d\n", rc));
        NOREF(rc);

#ifdef VBOX_STRICT
        cRefs = ASMAtomicReadU32(&pThis->cRefs);
        Assert(!cRefs);
#endif
        cRefs = 0;
    }
    else if (!cRefs)
    {
        /*
         * The ring-0 thread for this hook object has already died. Free up the object as we have no more references.
         */
        Assert(pThis->hOwner != RTThreadNativeSelf());
        ASMAtomicWriteU32(&pThis->u32Magic, ~RTTHREADCTXINT_MAGIC);
        RTMemFree(pThis);
    }

    return cRefs;
}


RTDECL(int) RTThreadCtxHooksRegister(RTTHREADCTX hThreadCtx, PFNRTTHREADCTXHOOK pfnThreadCtxHook, void *pvUser)
{
    /*
     * Validate input.
     */
    PRTTHREADCTXINT pThis = hThreadCtx;
    if (pThis == NIL_RTTHREADCTX)
        return VINF_SUCCESS;
    AssertPtr(pThis);
    AssertMsgReturn(pThis->u32Magic == RTTHREADCTXINT_MAGIC, ("pThis->u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis),
                    VERR_INVALID_HANDLE);
    Assert(pThis->hOwner == RTThreadNativeSelf());

    /*
     * Register the callback.
     */
    pThis->pvUser           = pvUser;
    pThis->pfnThreadCtxHook = pfnThreadCtxHook;
    pThis->fRegistered      = true;

    return VINF_SUCCESS;
}


RTDECL(int) RTThreadCtxHooksDeregister(RTTHREADCTX hThreadCtx)
{
    /*
     * Validate input.
     */
    PRTTHREADCTXINT pThis = hThreadCtx;
    if (pThis == NIL_RTTHREADCTX)
        return VINF_SUCCESS;
    AssertPtr(pThis);
    AssertMsgReturn(pThis->u32Magic == RTTHREADCTXINT_MAGIC, ("pThis->u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis),
                    VERR_INVALID_HANDLE);
    Assert(pThis->hOwner == RTThreadNativeSelf());
    Assert(pThis->fRegistered);

    /*
     * Deregister the callback.
     */
    pThis->fRegistered = false;

    return VINF_SUCCESS;
}