Adding upstream version 6.1.22-dfsg.upstream/6.1.22-dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 417 insertions, 0 deletions

diff --git a/src/VBox/Runtime/r3/linux/semevent-linux.cpp b/src/VBox/Runtime/r3/linux/semevent-linux.cpp
new file mode 100644
index 00000000..941b07e5
--- /dev/null
+++ b/src/VBox/Runtime/r3/linux/semevent-linux.cpp
@@ -0,0 +1,417 @@
+/* $Id: semevent-linux.cpp $ */
+/** @file
+ * IPRT - Event Semaphore, Linux (2.6.x+).
+ */
+
+/*
+ * Copyright (C) 2006-2020 Oracle Corporation
+ *
+ * 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.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+ * VirtualBox OSE distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ */
+
+#include <features.h>
+#if __GLIBC_PREREQ(2,6) && !defined(IPRT_WITH_FUTEX_BASED_SEMS)
+
+/*
+ * glibc 2.6 fixed a serious bug in the mutex implementation. We wrote this
+ * linux specific event semaphores code in order to work around the bug. We
+ * will fall back on the pthread-based implementation if glibc is known to
+ * contain the bug fix.
+ *
+ * The external reference to epoll_pwait is a hack which prevents that we link
+ * against glibc < 2.6.
+ */
+#include "../posix/semevent-posix.cpp"
+__asm__ (".global epoll_pwait");
+
+#else /* glibc < 2.6 */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#include <iprt/semaphore.h>
+#include "internal/iprt.h"
+
+#include <iprt/asm.h>
+#include <iprt/assert.h>
+#include <iprt/err.h>
+#include <iprt/lockvalidator.h>
+#include <iprt/mem.h>
+#include <iprt/time.h>
+#include "internal/magics.h"
+#include "internal/mem.h"
+#include "internal/strict.h"
+
+#include <errno.h>
+#include <limits.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <sys/time.h>
+#include <sys/syscall.h>
+#if 0 /* With 2.6.17 futex.h has become C++ unfriendly. */
+# include <linux/futex.h>
+#else
+# define FUTEX_WAIT 0
+# define FUTEX_WAKE 1
+#endif
+
+
+/*********************************************************************************************************************************
+*   Structures and Typedefs                                                                                                      *
+*********************************************************************************************************************************/
+/**
+ * Linux (single wakup) event semaphore.
+ */
+struct RTSEMEVENTINTERNAL
+{
+    /** Magic value. */
+    intptr_t volatile   iMagic;
+    /** The futex state variable.
+     * 0 means not signalled.
+       1 means signalled. */
+    uint32_t volatile   fSignalled;
+    /** The number of waiting threads */
+    int32_t volatile    cWaiters;
+#ifdef RTSEMEVENT_STRICT
+    /** Signallers. */
+    RTLOCKVALRECSHRD    Signallers;
+    /** Indicates that lock validation should be performed. */
+    bool volatile       fEverHadSignallers;
+#endif
+    /** The creation flags. */
+    uint32_t            fFlags;
+};
+
+
+/**
+ * Wrapper for the futex syscall.
+ */
+static long sys_futex(uint32_t volatile *uaddr, int op, int val, struct timespec *utime, int32_t *uaddr2, int val3)
+{
+    errno = 0;
+    long rc = syscall(__NR_futex, uaddr, op, val, utime, uaddr2, val3);
+    if (rc < 0)
+    {
+        Assert(rc == -1);
+        rc = -errno;
+    }
+    return rc;
+}
+
+
+
+RTDECL(int)  RTSemEventCreate(PRTSEMEVENT phEventSem)
+{
+    return RTSemEventCreateEx(phEventSem, 0 /*fFlags*/, NIL_RTLOCKVALCLASS, NULL);
+}
+
+
+RTDECL(int)  RTSemEventCreateEx(PRTSEMEVENT phEventSem, uint32_t fFlags, RTLOCKVALCLASS hClass, const char *pszNameFmt, ...)
+{
+    AssertReturn(!(fFlags & ~(RTSEMEVENT_FLAGS_NO_LOCK_VAL | RTSEMEVENT_FLAGS_BOOTSTRAP_HACK)), VERR_INVALID_PARAMETER);
+    Assert(!(fFlags & RTSEMEVENT_FLAGS_BOOTSTRAP_HACK) || (fFlags & RTSEMEVENT_FLAGS_NO_LOCK_VAL));
+
+    /*
+     * Allocate semaphore handle.
+     */
+    struct RTSEMEVENTINTERNAL *pThis;
+    if (!(fFlags & RTSEMEVENT_FLAGS_BOOTSTRAP_HACK))
+        pThis = (struct RTSEMEVENTINTERNAL *)RTMemAlloc(sizeof(struct RTSEMEVENTINTERNAL));
+    else
+        pThis = (struct RTSEMEVENTINTERNAL *)rtMemBaseAlloc(sizeof(struct RTSEMEVENTINTERNAL));
+    if (pThis)
+    {
+        pThis->iMagic = RTSEMEVENT_MAGIC;
+        pThis->cWaiters = 0;
+        pThis->fSignalled = 0;
+        pThis->fFlags = fFlags;
+#ifdef RTSEMEVENT_STRICT
+        if (!pszNameFmt)
+        {
+            static uint32_t volatile s_iSemEventAnon = 0;
+            RTLockValidatorRecSharedInit(&pThis->Signallers, hClass, RTLOCKVAL_SUB_CLASS_ANY, pThis,
+                                         true /*fSignaller*/, !(fFlags & RTSEMEVENT_FLAGS_NO_LOCK_VAL),
+                                         "RTSemEvent-%u", ASMAtomicIncU32(&s_iSemEventAnon) - 1);
+        }
+        else
+        {
+            va_list va;
+            va_start(va, pszNameFmt);
+            RTLockValidatorRecSharedInitV(&pThis->Signallers, hClass, RTLOCKVAL_SUB_CLASS_ANY, pThis,
+                                          true /*fSignaller*/, !(fFlags & RTSEMEVENT_FLAGS_NO_LOCK_VAL),
+                                          pszNameFmt, va);
+            va_end(va);
+        }
+        pThis->fEverHadSignallers = false;
+#else
+        RT_NOREF(hClass, pszNameFmt);
+#endif
+
+        *phEventSem = pThis;
+        return VINF_SUCCESS;
+    }
+    return  VERR_NO_MEMORY;
+}
+
+
+RTDECL(int)  RTSemEventDestroy(RTSEMEVENT hEventSem)
+{
+    /*
+     * Validate input.
+     */
+    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
+    if (pThis == NIL_RTSEMEVENT)
+        return VINF_SUCCESS;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->iMagic == RTSEMEVENT_MAGIC, VERR_INVALID_HANDLE);
+
+    /*
+     * Invalidate the semaphore and wake up anyone waiting on it.
+     */
+    ASMAtomicXchgSize(&pThis->iMagic, RTSEMEVENT_MAGIC | UINT32_C(0x80000000));
+    if (ASMAtomicXchgS32(&pThis->cWaiters, INT32_MIN / 2) > 0)
+    {
+        sys_futex(&pThis->fSignalled, FUTEX_WAKE, INT_MAX, NULL, NULL, 0);
+        usleep(1000);
+    }
+
+    /*
+     * Free the semaphore memory and be gone.
+     */
+#ifdef RTSEMEVENT_STRICT
+    RTLockValidatorRecSharedDelete(&pThis->Signallers);
+#endif
+    if (!(pThis->fFlags & RTSEMEVENT_FLAGS_BOOTSTRAP_HACK))
+        RTMemFree(pThis);
+    else
+        rtMemBaseFree(pThis);
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int)  RTSemEventSignal(RTSEMEVENT hEventSem)
+{
+    /*
+     * Validate input.
+     */
+    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->iMagic == RTSEMEVENT_MAGIC, VERR_INVALID_HANDLE);
+
+#ifdef RTSEMEVENT_STRICT
+    if (pThis->fEverHadSignallers)
+    {
+        int rc9 = RTLockValidatorRecSharedCheckSignaller(&pThis->Signallers, NIL_RTTHREAD);
+        if (RT_FAILURE(rc9))
+            return rc9;
+    }
+#endif
+
+    ASMAtomicWriteU32(&pThis->fSignalled, 1);
+    if (ASMAtomicReadS32(&pThis->cWaiters) < 1)
+        return VINF_SUCCESS;
+
+    /* somebody is waiting, try wake up one of them. */
+    long cWoken = sys_futex(&pThis->fSignalled, FUTEX_WAKE, 1, NULL, NULL, 0);
+    if (RT_LIKELY(cWoken >= 0))
+        return VINF_SUCCESS;
+
+    if (RT_UNLIKELY(pThis->iMagic != RTSEMEVENT_MAGIC))
+        return VERR_SEM_DESTROYED;
+
+    return VERR_INVALID_PARAMETER;
+}
+
+
+static int rtSemEventWait(RTSEMEVENT hEventSem, RTMSINTERVAL cMillies, bool fAutoResume)
+{
+#ifdef RTSEMEVENT_STRICT
+    PCRTLOCKVALSRCPOS pSrcPos = NULL;
+#endif
+
+    /*
+     * Validate input.
+     */
+    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->iMagic == RTSEMEVENT_MAGIC, VERR_INVALID_HANDLE);
+
+    /*
+     * Quickly check whether it's signaled.
+     */
+    /** @todo this isn't fair if someone is already waiting on it.  They should
+     *        have the first go at it!
+     *  (ASMAtomicReadS32(&pThis->cWaiters) == 0 || !cMillies) && ... */
+    if (ASMAtomicCmpXchgU32(&pThis->fSignalled, 0, 1))
+        return VINF_SUCCESS;
+
+    /*
+     * Convert the timeout value.
+     */
+    struct timespec ts;
+    struct timespec *pTimeout = NULL;
+    uint64_t u64End = 0; /* shut up gcc */
+    if (cMillies != RT_INDEFINITE_WAIT)
+    {
+        if (!cMillies)
+            return VERR_TIMEOUT;
+        ts.tv_sec  = cMillies / 1000;
+        ts.tv_nsec = (cMillies % 1000) * UINT32_C(1000000);
+        u64End = RTTimeSystemNanoTS() + cMillies * UINT64_C(1000000);
+        pTimeout = &ts;
+    }
+
+    ASMAtomicIncS32(&pThis->cWaiters);
+
+    /*
+     * The wait loop.
+     */
+#ifdef RTSEMEVENT_STRICT
+    RTTHREAD hThreadSelf = !(pThis->fFlags & RTSEMEVENT_FLAGS_BOOTSTRAP_HACK)
+                         ? RTThreadSelfAutoAdopt()
+                         : RTThreadSelf();
+#else
+    RTTHREAD hThreadSelf = RTThreadSelf();
+#endif
+    int rc = VINF_SUCCESS;
+    for (;;)
+    {
+#ifdef RTSEMEVENT_STRICT
+        if (pThis->fEverHadSignallers)
+        {
+            rc = RTLockValidatorRecSharedCheckBlocking(&pThis->Signallers, hThreadSelf, pSrcPos, false,
+                                                       cMillies, RTTHREADSTATE_EVENT, true);
+            if (RT_FAILURE(rc))
+                break;
+        }
+#endif
+        RTThreadBlocking(hThreadSelf, RTTHREADSTATE_EVENT, true);
+        long lrc = sys_futex(&pThis->fSignalled, FUTEX_WAIT, 0, pTimeout, NULL, 0);
+        RTThreadUnblocked(hThreadSelf, RTTHREADSTATE_EVENT);
+        if (RT_UNLIKELY(pThis->iMagic != RTSEMEVENT_MAGIC))
+        {
+            rc = VERR_SEM_DESTROYED;
+            break;
+        }
+
+        if (RT_LIKELY(lrc == 0 || lrc == -EWOULDBLOCK))
+        {
+            /* successful wakeup or fSignalled > 0 in the meantime */
+            if (ASMAtomicCmpXchgU32(&pThis->fSignalled, 0, 1))
+                break;
+        }
+        else if (lrc == -ETIMEDOUT)
+        {
+            rc = VERR_TIMEOUT;
+            break;
+        }
+        else if (lrc == -EINTR)
+        {
+            if (!fAutoResume)
+            {
+                rc = VERR_INTERRUPTED;
+                break;
+            }
+        }
+        else
+        {
+            /* this shouldn't happen! */
+            AssertMsgFailed(("rc=%ld errno=%d\n", lrc, errno));
+            rc = RTErrConvertFromErrno(lrc);
+            break;
+        }
+        /* adjust the relative timeout */
+        if (pTimeout)
+        {
+            int64_t i64Diff = u64End - RTTimeSystemNanoTS();
+            if (i64Diff < 1000)
+            {
+                rc = VERR_TIMEOUT;
+                break;
+            }
+            ts.tv_sec  = (uint64_t)i64Diff / UINT32_C(1000000000);
+            ts.tv_nsec = (uint64_t)i64Diff % UINT32_C(1000000000);
+        }
+    }
+
+    ASMAtomicDecS32(&pThis->cWaiters);
+    return rc;
+}
+
+
+RTDECL(int)  RTSemEventWait(RTSEMEVENT hEventSem, RTMSINTERVAL cMillies)
+{
+    int rc = rtSemEventWait(hEventSem, cMillies, true);
+    Assert(rc != VERR_INTERRUPTED);
+    Assert(rc != VERR_TIMEOUT || cMillies != RT_INDEFINITE_WAIT);
+    return rc;
+}
+
+
+RTDECL(int)  RTSemEventWaitNoResume(RTSEMEVENT hEventSem, RTMSINTERVAL cMillies)
+{
+    return rtSemEventWait(hEventSem, cMillies, false);
+}
+
+
+RTDECL(void) RTSemEventSetSignaller(RTSEMEVENT hEventSem, RTTHREAD hThread)
+{
+#ifdef RTSEMEVENT_STRICT
+    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
+    AssertPtrReturnVoid(pThis);
+    AssertReturnVoid(pThis->iMagic == RTSEMEVENT_MAGIC);
+
+    ASMAtomicWriteBool(&pThis->fEverHadSignallers, true);
+    RTLockValidatorRecSharedResetOwner(&pThis->Signallers, hThread, NULL);
+#else
+    RT_NOREF(hEventSem, hThread);
+#endif
+}
+
+
+RTDECL(void) RTSemEventAddSignaller(RTSEMEVENT hEventSem, RTTHREAD hThread)
+{
+#ifdef RTSEMEVENT_STRICT
+    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
+    AssertPtrReturnVoid(pThis);
+    AssertReturnVoid(pThis->iMagic == RTSEMEVENT_MAGIC);
+
+    ASMAtomicWriteBool(&pThis->fEverHadSignallers, true);
+    RTLockValidatorRecSharedAddOwner(&pThis->Signallers, hThread, NULL);
+#else
+    RT_NOREF(hEventSem, hThread);
+#endif
+}
+
+
+RTDECL(void) RTSemEventRemoveSignaller(RTSEMEVENT hEventSem, RTTHREAD hThread)
+{
+#ifdef RTSEMEVENT_STRICT
+    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
+    AssertPtrReturnVoid(pThis);
+    AssertReturnVoid(pThis->iMagic == RTSEMEVENT_MAGIC);
+
+    RTLockValidatorRecSharedRemoveOwner(&pThis->Signallers, hThread);
+#else
+    RT_NOREF(hEventSem, hThread);
+#endif
+}
+
+#endif /* glibc < 2.6 || IPRT_WITH_FUTEX_BASED_SEMS */
+