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Diffstat (limited to 'include/iprt/cpuset.h')
| -rw-r--r-- | include/iprt/cpuset.h | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/include/iprt/cpuset.h b/include/iprt/cpuset.h new file mode 100644 index 00000000..c5882472 --- /dev/null +++ b/include/iprt/cpuset.h @@ -0,0 +1,353 @@ +/** @file + * IPRT - CPU Set. + */ + +/* + * Copyright (C) 2008-2022 Oracle and/or its affiliates. + * + * This file is part of VirtualBox base platform packages, as + * available from https://www.virtualbox.org. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, in version 3 of the + * License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <https://www.gnu.org/licenses>. + * + * The contents of this file may alternatively be used under the terms + * of the Common Development and Distribution License Version 1.0 + * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included + * in the VirtualBox 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. + * + * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 + */ + +#ifndef IPRT_INCLUDED_cpuset_h +#define IPRT_INCLUDED_cpuset_h +#ifndef RT_WITHOUT_PRAGMA_ONCE +# pragma once +#endif + +#include <iprt/types.h> +#include <iprt/mp.h> /* RTMpCpuIdToSetIndex */ +#include <iprt/asm.h> + + +RT_C_DECLS_BEGIN + +/** @defgroup grp_rt_cpuset RTCpuSet - CPU Set + * @ingroup grp_rt + * @{ + */ + + +/** + * Clear all CPUs. + * + * @returns pSet. + * @param pSet Pointer to the set. + */ +DECLINLINE(PRTCPUSET) RTCpuSetEmpty(PRTCPUSET pSet) +{ + size_t i; + for (i = 0; i < RT_ELEMENTS(pSet->bmSet); i++) + pSet->bmSet[i] = 0; + return pSet; +} + + +/** + * Set all CPUs. + * + * @returns pSet. + * @param pSet Pointer to the set. + */ +DECLINLINE(PRTCPUSET) RTCpuSetFill(PRTCPUSET pSet) +{ + size_t i; + for (i = 0; i < RT_ELEMENTS(pSet->bmSet); i++) + pSet->bmSet[i] = UINT64_MAX; + return pSet; +} + + +/** + * Copies one set to another. + * + * @param pDst Pointer to the destination set. + * @param pSrc Pointer to the source set. + */ +DECLINLINE(void) RTCpuSetCopy(PRTCPUSET pDst, PRTCPUSET pSrc) +{ + size_t i; + for (i = 0; i < RT_ELEMENTS(pDst->bmSet); i++) + pDst->bmSet[i] = pSrc->bmSet[i]; +} + + +/** + * ANDs the given CPU set with another. + * + * @returns pSet. + * @param pSet Pointer to the set. + * @param pAndMaskSet Pointer to the AND-mask set. + */ +DECLINLINE(PRTCPUSET) RTCpuSetAnd(PRTCPUSET pSet, PRTCPUSET pAndMaskSet) +{ + size_t i; + for (i = 0; i < RT_ELEMENTS(pSet->bmSet); i++) + ASMAtomicAndU64((volatile uint64_t *)&pSet->bmSet[i], pAndMaskSet->bmSet[i]); + return pSet; +} + + +/** + * Adds a CPU given by its identifier to the set. + * + * @returns 0 on success, -1 if idCpu isn't valid. + * @param pSet Pointer to the set. + * @param idCpu The identifier of the CPU to add. + * @remarks The modification is atomic. + */ +DECLINLINE(int) RTCpuSetAdd(PRTCPUSET pSet, RTCPUID idCpu) +{ + int iCpu = RTMpCpuIdToSetIndex(idCpu); + if (RT_LIKELY(iCpu >= 0)) + { + ASMAtomicBitSet(pSet, iCpu); + return 0; + } + return -1; +} + + +/** + * Adds a CPU given by its identifier to the set. + * + * @returns 0 on success, -1 if iCpu isn't valid. + * @param pSet Pointer to the set. + * @param iCpu The index of the CPU to add. + * @remarks The modification is atomic. + */ +DECLINLINE(int) RTCpuSetAddByIndex(PRTCPUSET pSet, int iCpu) +{ + if (RT_LIKELY((unsigned)iCpu < RTCPUSET_MAX_CPUS)) + { + ASMAtomicBitSet(pSet, iCpu); + return 0; + } + return -1; +} + + +/** + * Removes a CPU given by its identifier from the set. + * + * @returns 0 on success, -1 if idCpu isn't valid. + * @param pSet Pointer to the set. + * @param idCpu The identifier of the CPU to delete. + * @remarks The modification is atomic. + */ +DECLINLINE(int) RTCpuSetDel(PRTCPUSET pSet, RTCPUID idCpu) +{ + int iCpu = RTMpCpuIdToSetIndex(idCpu); + if (RT_LIKELY(iCpu >= 0)) + { + ASMAtomicBitClear(pSet, iCpu); + return 0; + } + return -1; +} + + +/** + * Removes a CPU given by its index from the set. + * + * @returns 0 on success, -1 if iCpu isn't valid. + * @param pSet Pointer to the set. + * @param iCpu The index of the CPU to delete. + * @remarks The modification is atomic. + */ +DECLINLINE(int) RTCpuSetDelByIndex(PRTCPUSET pSet, int iCpu) +{ + if (RT_LIKELY((unsigned)iCpu < RTCPUSET_MAX_CPUS)) + { + ASMAtomicBitClear(pSet, iCpu); + return 0; + } + return -1; +} + + +/** + * Checks if a CPU given by its identifier is a member of the set. + * + * @returns true / false accordingly. + * @param pSet Pointer to the set. + * @param idCpu The identifier of the CPU to look for. + * @remarks The test is atomic. + */ +DECLINLINE(bool) RTCpuSetIsMember(PCRTCPUSET pSet, RTCPUID idCpu) +{ + int iCpu = RTMpCpuIdToSetIndex(idCpu); + if (RT_LIKELY(iCpu >= 0)) + return ASMBitTest((volatile void *)pSet, iCpu); + return false; +} + + +/** + * Checks if a CPU given by its index is a member of the set. + * + * @returns true / false accordingly. + * @param pSet Pointer to the set. + * @param iCpu The index of the CPU in the set. + * @remarks The test is atomic. + */ +DECLINLINE(bool) RTCpuSetIsMemberByIndex(PCRTCPUSET pSet, int iCpu) +{ + if (RT_LIKELY((unsigned)iCpu < RTCPUSET_MAX_CPUS)) + return ASMBitTest((volatile void *)pSet, iCpu); + return false; +} + + +/** + * Checks if the two sets match or not. + * + * @returns true / false accordingly. + * @param pSet1 The first set. + * @param pSet2 The second set. + */ +DECLINLINE(bool) RTCpuSetIsEqual(PCRTCPUSET pSet1, PCRTCPUSET pSet2) +{ + size_t i; + for (i = 0; i < RT_ELEMENTS(pSet1->bmSet); i++) + if (pSet1->bmSet[i] != pSet2->bmSet[i]) + return false; + return true; +} + + +/** + * Checks if the CPU set is empty or not. + * + * @returns true / false accordingly. + * @param pSet Pointer to the set. + */ +DECLINLINE(bool) RTCpuSetIsEmpty(PRTCPUSET pSet) +{ + size_t i; + for (i = 0; i < RT_ELEMENTS(pSet->bmSet); i++) + if (pSet->bmSet[i]) + return false; + return true; +} + + +/** + * Converts the CPU set to a 64-bit mask. + * + * @returns The mask. + * @param pSet Pointer to the set. + * @remarks Use with extreme care as it may lose information! + */ +DECLINLINE(uint64_t) RTCpuSetToU64(PCRTCPUSET pSet) +{ + return pSet->bmSet[0]; +} + + +/** + * Initializes the CPU set from a 64-bit mask. + * + * @param pSet Pointer to the set. + * @param fMask The mask. + */ +DECLINLINE(PRTCPUSET) RTCpuSetFromU64(PRTCPUSET pSet, uint64_t fMask) +{ + size_t i; + + pSet->bmSet[0] = fMask; + for (i = 1; i < RT_ELEMENTS(pSet->bmSet); i++) + pSet->bmSet[i] = 0; + + return pSet; +} + + +/** + * Count the CPUs in the set. + * + * @returns CPU count. + * @param pSet Pointer to the set. + */ +DECLINLINE(int) RTCpuSetCount(PCRTCPUSET pSet) +{ + int cCpus = 0; + size_t i; + + for (i = 0; i < RT_ELEMENTS(pSet->bmSet); i++) + { + uint64_t u64 = pSet->bmSet[i]; + if (u64 != 0) + { + unsigned iCpu = 64; + while (iCpu-- > 0) + { + if (u64 & 1) + cCpus++; + u64 >>= 1; + } + } + } + return cCpus; +} + + +/** + * Get the highest set index. + * + * @returns The higest set index, -1 if all bits are clear. + * @param pSet Pointer to the set. + */ +DECLINLINE(int) RTCpuLastIndex(PCRTCPUSET pSet) +{ + size_t i = RT_ELEMENTS(pSet->bmSet); + while (i-- > 0) + { + uint64_t u64 = pSet->bmSet[i]; + if (u64) + { + /* There are more efficient ways to do this in asm.h... */ + unsigned iBit; + for (iBit = 63; iBit > 0; iBit--) + { + if (u64 & RT_BIT_64(63)) + break; + u64 <<= 1; + } + return (int)i * 64 + (int)iBit; + } + } + return 0; +} + + +/** @} */ + +RT_C_DECLS_END + +#endif /* !IPRT_INCLUDED_cpuset_h */ + |