diff options
Diffstat (limited to 'src/VBox/Runtime/r0drv/netbsd/sleepqueue-r0drv-netbsd.h')
| -rw-r--r-- | src/VBox/Runtime/r0drv/netbsd/sleepqueue-r0drv-netbsd.h | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/src/VBox/Runtime/r0drv/netbsd/sleepqueue-r0drv-netbsd.h b/src/VBox/Runtime/r0drv/netbsd/sleepqueue-r0drv-netbsd.h new file mode 100644 index 00000000..e90bb7c6 --- /dev/null +++ b/src/VBox/Runtime/r0drv/netbsd/sleepqueue-r0drv-netbsd.h @@ -0,0 +1,281 @@ +/* $Id: sleepqueue-r0drv-netbsd.h $ */ +/** @file + * IPRT - NetBSD Ring-0 Driver Helpers for Abstracting Sleep Queues, + */ + +/* + * 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. + */ + +#ifndef IPRT_INCLUDED_SRC_r0drv_netbsd_sleepqueue_r0drv_netbsd_h +#define IPRT_INCLUDED_SRC_r0drv_netbsd_sleepqueue_r0drv_netbsd_h +#ifndef RT_WITHOUT_PRAGMA_ONCE +# pragma once +#endif + +#include "the-netbsd-kernel.h" + +#include <iprt/asm-math.h> +#include <iprt/err.h> +#include <iprt/time.h> + +static syncobj_t vbox_syncobj = { + SOBJ_SLEEPQ_SORTED, + sleepq_unsleep, + sleepq_changepri, + sleepq_lendpri, + syncobj_noowner, +}; + +/** + * Kernel mode NetBSD wait state structure. + */ +typedef struct RTR0SEMBSDSLEEP +{ + /** The absolute timeout given as nano seconds since the start of the + * monotonic clock. */ + uint64_t uNsAbsTimeout; + /** The timeout in ticks. Updated after waiting. */ + int iTimeout; + /** Set if it's an indefinite wait. */ + bool fIndefinite; + /** Set if we've already timed out. + * Set by rtR0SemBsdWaitDoIt and read by rtR0SemBsdWaitHasTimedOut. */ + bool fTimedOut; + /** Flag whether the wait was interrupted. */ + bool fInterrupted; + /** flag whether the wait is interruptible or not. */ + bool fInterruptible; + /** Opaque wait channel id. */ + wchan_t wchan; + sleepq_t *sq; + kmutex_t *sq_lock; +} RTR0SEMBSDSLEEP; +/** Pointer to a NetBSD wait state. */ +typedef RTR0SEMBSDSLEEP *PRTR0SEMBSDSLEEP; + + +/** + * Updates the timeout of the NetBSD wait. + * + * @returns RTSEMWAIT_FLAGS_INDEFINITE if the timeout value is too big. + * 0 otherwise + * @param pWait The wait structure. + * @param uTimeout The relative timeout in nanoseconds. + */ +DECLINLINE(void) rtR0SemBsdWaitUpdateTimeout(PRTR0SEMBSDSLEEP pWait) +{ + /* Convert absolute timeout to ticks */ + uint64_t now = RTTimeNanoTS(); + if (now >= pWait->uNsAbsTimeout) { + pWait->iTimeout = 0; + } else { + uint64_t nanos = pWait->uNsAbsTimeout - now; + pWait->iTimeout = hz * nanos / 1000000000; + /* for 1ms wait, wait at least one tick ?? */ + if ((pWait->iTimeout == 0) && (nanos >= 1000000)) { + pWait->iTimeout = 1; + } + } +} + +/** + * Initializes a wait. + * + * The caller MUST check the wait condition BEFORE calling this function or the + * timeout logic will be flawed. + * + * @returns VINF_SUCCESS or VERR_TIMEOUT. + * @param pWait The wait structure. + * @param fFlags The wait flags. + * @param uTimeout The timeout. + * @param pvWaitChan The opaque wait channel. + */ +DECLINLINE(int) rtR0SemBsdWaitInit(PRTR0SEMBSDSLEEP pWait, uint32_t fFlags, uint64_t uTimeout, + void *pvWaitChan) +{ + if (fFlags & RTSEMWAIT_FLAGS_INDEFINITE) { + pWait->fIndefinite = true; + pWait->iTimeout = 0; + pWait->uNsAbsTimeout = 0; + } else { + if (fFlags & RTSEMWAIT_FLAGS_RELATIVE) { + if (fFlags & RTSEMWAIT_FLAGS_MILLISECS) { + pWait->uNsAbsTimeout = uTimeout * 1000000 + RTTimeSystemNanoTS(); + } else { + pWait->uNsAbsTimeout = uTimeout + RTTimeSystemNanoTS(); + } + } else { + if (fFlags & RTSEMWAIT_FLAGS_MILLISECS) { + pWait->uNsAbsTimeout = uTimeout * 1000000; + } else { + pWait->uNsAbsTimeout = uTimeout; + } + } + rtR0SemBsdWaitUpdateTimeout(pWait); + if (pWait->iTimeout == 0) { + return VERR_TIMEOUT; + } + } + + pWait->fTimedOut = false; + /* + * Initialize the wait queue related bits. + */ + pWait->fInterruptible = fFlags & RTSEMWAIT_FLAGS_INTERRUPTIBLE + ? true : false; + pWait->fInterrupted = false; + pWait->wchan = pvWaitChan; + pWait->sq = NULL; + pWait->sq_lock = NULL; + + return VINF_SUCCESS; +} + +/** + * Prepares the next wait. + * + * This must be called before rtR0SemBsdWaitDoIt, and the caller should check + * the exit conditions inbetween the two calls. + * + * @param pWait The wait structure. + */ +DECLINLINE(void) rtR0SemBsdWaitPrepare(PRTR0SEMBSDSLEEP pWait) +{ + pWait->sq = sleeptab_lookup(&sleeptab, pWait->wchan, &pWait->sq_lock); +} + +/** + * Do the actual wait. + * + * @param pWait The wait structure. + */ +DECLINLINE(void) rtR0SemBsdWaitDoIt(PRTR0SEMBSDSLEEP pWait) +{ + sleepq_enter(pWait->sq, curlwp, pWait->sq_lock); + sleepq_enqueue(pWait->sq, pWait->wchan, "VBoxIS", &vbox_syncobj); + + pWait->sq = NULL; + pWait->sq_lock = NULL; + + int error = sleepq_block(pWait->iTimeout, pWait->fInterruptible); + if (error == EWOULDBLOCK) { + if (!pWait->fIndefinite) { + pWait->fTimedOut = true; + } + } else if (error == ERESTART) { + if (pWait->fInterruptible) { + pWait->fInterrupted = true; + } else if (!pWait->fIndefinite) { + rtR0SemBsdWaitUpdateTimeout(pWait); + if (pWait->iTimeout == 0) { + pWait->fTimedOut = true; + } + } + } else if (error == EINTR) { + if (pWait->fInterruptible) { + pWait->fInterrupted = true; + } else if (!pWait->fIndefinite) { + rtR0SemBsdWaitUpdateTimeout(pWait); + if (pWait->iTimeout == 0) { + pWait->fTimedOut = true; + } + } + } else if (error) { + AssertMsgFailed(("sleepq_block -> %d\n", error)); + } +} + + +/** + * Checks if a NetBSD wait was interrupted. + * + * @returns true / false + * @param pWait The wait structure. + * @remarks This shall be called before the first rtR0SemLnxWaitDoIt(). + */ +DECLINLINE(bool) rtR0SemBsdWaitWasInterrupted(PRTR0SEMBSDSLEEP pWait) +{ + return pWait->fInterrupted; +} + + +/** + * Checks if a NetBSD wait has timed out. + * + * @returns true / false + * @param pWait The wait structure. + */ +DECLINLINE(bool) rtR0SemBsdWaitHasTimedOut(PRTR0SEMBSDSLEEP pWait) +{ + return pWait->fTimedOut; +} + + +/** + * Deletes a NetBSD wait. + * + * @param pWait The wait structure. + */ +DECLINLINE(void) rtR0SemBsdWaitDelete(PRTR0SEMBSDSLEEP pWait) +{ + if (pWait->sq_lock != NULL) { + mutex_spin_exit(pWait->sq_lock); + pWait->sq = NULL; + pWait->sq_lock = NULL; + } +} + + +/** + * Signals the wait channel. + * + * @param pvWaitChan The opaque wait channel handle. + */ +DECLINLINE(void) rtR0SemBsdSignal(void *pvWaitChan) +{ + kmutex_t *mp; + sleepq_t *sq = sleeptab_lookup(&sleeptab, pvWaitChan, &mp); + sleepq_wake(sq, pvWaitChan, 1, mp); +} + +/** + * Wakes up all waiters on the wait channel. + * + * @param pvWaitChan The opaque wait channel handle. + */ +DECLINLINE(void) rtR0SemBsdBroadcast(void *pvWaitChan) +{ + kmutex_t *mp; + sleepq_t *sq = sleeptab_lookup(&sleeptab, pvWaitChan, &mp); + sleepq_wake(sq, pvWaitChan, ~0u, mp); +} + +/** + * Gets the max resolution of the timeout machinery. + * + * @returns Resolution specified in nanoseconds. + */ +DECLINLINE(uint32_t) rtR0SemBsdWaitGetResolution(void) +{ + return 1000000000 / hz; /* ns */ +} + +#endif /* !IPRT_INCLUDED_SRC_r0drv_netbsd_sleepqueue_r0drv_netbsd_h */ |