diff options
Diffstat (limited to 'src/VBox/Runtime/r0drv/linux/thread-r0drv-linux.c')
| -rw-r--r-- | src/VBox/Runtime/r0drv/linux/thread-r0drv-linux.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/src/VBox/Runtime/r0drv/linux/thread-r0drv-linux.c b/src/VBox/Runtime/r0drv/linux/thread-r0drv-linux.c new file mode 100644 index 00000000..c8e0c9d3 --- /dev/null +++ b/src/VBox/Runtime/r0drv/linux/thread-r0drv-linux.c @@ -0,0 +1,234 @@ +/* $Id: thread-r0drv-linux.c $ */ +/** @file + * IPRT - Threads, Ring-0 Driver, Linux. + */ + +/* + * Copyright (C) 2006-2019 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. + */ + + +/********************************************************************************************************************************* +* Header Files * +*********************************************************************************************************************************/ +#include "the-linux-kernel.h" +#include "internal/iprt.h" +#include <iprt/thread.h> + +#include <iprt/asm.h> +#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 5, 28) || defined(CONFIG_X86_SMAP) +# include <iprt/asm-amd64-x86.h> +#endif +#include <iprt/assert.h> +#include <iprt/errcore.h> +#include <iprt/mp.h> + + +/********************************************************************************************************************************* +* Global Variables * +*********************************************************************************************************************************/ +#ifndef CONFIG_PREEMPT +/** Per-cpu preemption counters. */ +static int32_t volatile g_acPreemptDisabled[NR_CPUS]; +#endif + + +RTDECL(RTNATIVETHREAD) RTThreadNativeSelf(void) +{ + return (RTNATIVETHREAD)current; +} +RT_EXPORT_SYMBOL(RTThreadNativeSelf); + + +static int rtR0ThreadLnxSleepCommon(RTMSINTERVAL cMillies) +{ + IPRT_LINUX_SAVE_EFL_AC(); + long cJiffies = msecs_to_jiffies(cMillies); + set_current_state(TASK_INTERRUPTIBLE); + cJiffies = schedule_timeout(cJiffies); + IPRT_LINUX_RESTORE_EFL_AC(); + if (!cJiffies) + return VINF_SUCCESS; + return VERR_INTERRUPTED; +} + + +RTDECL(int) RTThreadSleep(RTMSINTERVAL cMillies) +{ + return rtR0ThreadLnxSleepCommon(cMillies); +} +RT_EXPORT_SYMBOL(RTThreadSleep); + + +RTDECL(int) RTThreadSleepNoLog(RTMSINTERVAL cMillies) +{ + return rtR0ThreadLnxSleepCommon(cMillies); +} +RT_EXPORT_SYMBOL(RTThreadSleepNoLog); + + +RTDECL(bool) RTThreadYield(void) +{ + IPRT_LINUX_SAVE_EFL_AC(); +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 20) + yield(); +#else + /** @todo r=ramshankar: Can we use cond_resched() instead? */ + set_current_state(TASK_RUNNING); + sys_sched_yield(); + schedule(); +#endif + IPRT_LINUX_RESTORE_EFL_AC(); + return true; +} +RT_EXPORT_SYMBOL(RTThreadYield); + + +RTDECL(bool) RTThreadPreemptIsEnabled(RTTHREAD hThread) +{ +#ifdef CONFIG_PREEMPT + Assert(hThread == NIL_RTTHREAD); RT_NOREF_PV(hThread); +# ifdef preemptible + return preemptible(); +# else + return preempt_count() == 0 && !in_atomic() && !irqs_disabled(); +# endif +#else + int32_t c; + + Assert(hThread == NIL_RTTHREAD); + c = g_acPreemptDisabled[smp_processor_id()]; + AssertMsg(c >= 0 && c < 32, ("%d\n", c)); + if (c != 0) + return false; +# if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 5, 32) + if (in_atomic()) + return false; +# endif +# if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 5, 28) + if (irqs_disabled()) + return false; +# else + if (!ASMIntAreEnabled()) + return false; +# endif + return true; +#endif +} +RT_EXPORT_SYMBOL(RTThreadPreemptIsEnabled); + + +RTDECL(bool) RTThreadPreemptIsPending(RTTHREAD hThread) +{ + Assert(hThread == NIL_RTTHREAD); RT_NOREF_PV(hThread); +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 5, 4) + return !!test_tsk_thread_flag(current, TIF_NEED_RESCHED); + +#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 20) + return !!need_resched(); + +#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2, 1, 110) + return current->need_resched != 0; + +#else + return need_resched != 0; +#endif +} +RT_EXPORT_SYMBOL(RTThreadPreemptIsPending); + + +RTDECL(bool) RTThreadPreemptIsPendingTrusty(void) +{ + /* yes, RTThreadPreemptIsPending is reliable. */ + return true; +} +RT_EXPORT_SYMBOL(RTThreadPreemptIsPendingTrusty); + + +RTDECL(bool) RTThreadPreemptIsPossible(void) +{ +#ifdef CONFIG_PREEMPT + return true; /* Yes, kernel preemption is possible. */ +#else + return false; /* No kernel preemption (or CONFIG_PREEMPT_VOLUNTARY). */ +#endif +} +RT_EXPORT_SYMBOL(RTThreadPreemptIsPossible); + + +RTDECL(void) RTThreadPreemptDisable(PRTTHREADPREEMPTSTATE pState) +{ +#ifdef CONFIG_PREEMPT + AssertPtr(pState); + Assert(pState->u32Reserved == 0); + pState->u32Reserved = 42; + /* This ASSUMES that CONFIG_PREEMPT_COUNT is always defined with CONFIG_PREEMPT. */ + preempt_disable(); + RT_ASSERT_PREEMPT_CPUID_DISABLE(pState); + +#else /* !CONFIG_PREEMPT */ + int32_t c; + AssertPtr(pState); + Assert(pState->u32Reserved == 0); + + /* Do our own accounting. */ + c = ASMAtomicIncS32(&g_acPreemptDisabled[smp_processor_id()]); + AssertMsg(c > 0 && c < 32, ("%d\n", c)); + pState->u32Reserved = c; + RT_ASSERT_PREEMPT_CPUID_DISABLE(pState); +#endif +} +RT_EXPORT_SYMBOL(RTThreadPreemptDisable); + + +RTDECL(void) RTThreadPreemptRestore(PRTTHREADPREEMPTSTATE pState) +{ +#ifdef CONFIG_PREEMPT + IPRT_LINUX_SAVE_EFL_AC(); /* paranoia */ + AssertPtr(pState); + Assert(pState->u32Reserved == 42); + RT_ASSERT_PREEMPT_CPUID_RESTORE(pState); + preempt_enable(); + IPRT_LINUX_RESTORE_EFL_ONLY_AC(); /* paranoia */ + +#else + int32_t volatile *pc; + AssertPtr(pState); + AssertMsg(pState->u32Reserved > 0 && pState->u32Reserved < 32, ("%d\n", pState->u32Reserved)); + RT_ASSERT_PREEMPT_CPUID_RESTORE(pState); + + /* Do our own accounting. */ + pc = &g_acPreemptDisabled[smp_processor_id()]; + AssertMsg(pState->u32Reserved == (uint32_t)*pc, ("u32Reserved=%d *pc=%d \n", pState->u32Reserved, *pc)); + ASMAtomicUoWriteS32(pc, pState->u32Reserved - 1); +#endif + pState->u32Reserved = 0; +} +RT_EXPORT_SYMBOL(RTThreadPreemptRestore); + + +RTDECL(bool) RTThreadIsInInterrupt(RTTHREAD hThread) +{ + Assert(hThread == NIL_RTTHREAD); NOREF(hThread); + + return in_interrupt() != 0; +} +RT_EXPORT_SYMBOL(RTThreadIsInInterrupt); + |