From 247c9de13f9d54a94734875000a9faea8168c8ca Mon Sep 17 00:00:00 2001 From: Eduardo Habkost Date: Wed, 23 Jan 2013 15:58:27 -0200 Subject: [PATCH] target-i386: Topology & APIC ID utility functions MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This introduces utility functions for the APIC ID calculation, based on: Intel® 64 Architecture Processor Topology Enumeration http://software.intel.com/en-us/articles/intel-64-architecture-processor-topology-enumeration/ The code should be compatible with AMD's "Extended Method" described at: AMD CPUID Specification (Publication #25481) Section 3: Multiple Core Calcuation as long as: - nr_threads is set to 1; - OFFSET_IDX is assumed to be 0; - CPUID Fn8000_0008_ECX[ApicIdCoreIdSize[3:0]] is set to apicid_core_width(). Unit tests included. Signed-off-by: Eduardo Habkost Signed-off-by: Andreas Färber --- target-i386/topology.h | 136 +++++++++++++++++++++++++++++++++++++++++++++++++ tests/.gitignore | 1 + tests/Makefile | 9 +++- tests/test-x86-cpuid.c | 110 +++++++++++++++++++++++++++++++++++++++ 4 files changed, 255 insertions(+), 1 deletion(-) create mode 100644 target-i386/topology.h create mode 100644 tests/test-x86-cpuid.c diff --git a/target-i386/topology.h b/target-i386/topology.h new file mode 100644 index 0000000000..24ed525453 --- /dev/null +++ b/target-i386/topology.h @@ -0,0 +1,136 @@ +/* + * x86 CPU topology data structures and functions + * + * Copyright (c) 2012 Red Hat Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#ifndef TARGET_I386_TOPOLOGY_H +#define TARGET_I386_TOPOLOGY_H + +/* This file implements the APIC-ID-based CPU topology enumeration logic, + * documented at the following document: + * Intel® 64 Architecture Processor Topology Enumeration + * http://software.intel.com/en-us/articles/intel-64-architecture-processor-topology-enumeration/ + * + * This code should be compatible with AMD's "Extended Method" described at: + * AMD CPUID Specification (Publication #25481) + * Section 3: Multiple Core Calcuation + * as long as: + * nr_threads is set to 1; + * OFFSET_IDX is assumed to be 0; + * CPUID Fn8000_0008_ECX[ApicIdCoreIdSize[3:0]] is set to apicid_core_width(). + */ + +#include +#include + +#include "qemu/bitops.h" + +/* APIC IDs can be 32-bit, but beware: APIC IDs > 255 require x2APIC support + */ +typedef uint32_t apic_id_t; + +/* Return the bit width needed for 'count' IDs + */ +static unsigned apicid_bitwidth_for_count(unsigned count) +{ + g_assert(count >= 1); + if (count == 1) { + return 0; + } + return bitops_flsl(count - 1) + 1; +} + +/* Bit width of the SMT_ID (thread ID) field on the APIC ID + */ +static inline unsigned apicid_smt_width(unsigned nr_cores, unsigned nr_threads) +{ + return apicid_bitwidth_for_count(nr_threads); +} + +/* Bit width of the Core_ID field + */ +static inline unsigned apicid_core_width(unsigned nr_cores, unsigned nr_threads) +{ + return apicid_bitwidth_for_count(nr_cores); +} + +/* Bit offset of the Core_ID field + */ +static inline unsigned apicid_core_offset(unsigned nr_cores, + unsigned nr_threads) +{ + return apicid_smt_width(nr_cores, nr_threads); +} + +/* Bit offset of the Pkg_ID (socket ID) field + */ +static inline unsigned apicid_pkg_offset(unsigned nr_cores, unsigned nr_threads) +{ + return apicid_core_offset(nr_cores, nr_threads) + + apicid_core_width(nr_cores, nr_threads); +} + +/* Make APIC ID for the CPU based on Pkg_ID, Core_ID, SMT_ID + * + * The caller must make sure core_id < nr_cores and smt_id < nr_threads. + */ +static inline apic_id_t apicid_from_topo_ids(unsigned nr_cores, + unsigned nr_threads, + unsigned pkg_id, + unsigned core_id, + unsigned smt_id) +{ + return (pkg_id << apicid_pkg_offset(nr_cores, nr_threads)) | + (core_id << apicid_core_offset(nr_cores, nr_threads)) | + smt_id; +} + +/* Calculate thread/core/package IDs for a specific topology, + * based on (contiguous) CPU index + */ +static inline void x86_topo_ids_from_idx(unsigned nr_cores, + unsigned nr_threads, + unsigned cpu_index, + unsigned *pkg_id, + unsigned *core_id, + unsigned *smt_id) +{ + unsigned core_index = cpu_index / nr_threads; + *smt_id = cpu_index % nr_threads; + *core_id = core_index % nr_cores; + *pkg_id = core_index / nr_cores; +} + +/* Make APIC ID for the CPU 'cpu_index' + * + * 'cpu_index' is a sequential, contiguous ID for the CPU. + */ +static inline apic_id_t x86_apicid_from_cpu_idx(unsigned nr_cores, + unsigned nr_threads, + unsigned cpu_index) +{ + unsigned pkg_id, core_id, smt_id; + x86_topo_ids_from_idx(nr_cores, nr_threads, cpu_index, + &pkg_id, &core_id, &smt_id); + return apicid_from_topo_ids(nr_cores, nr_threads, pkg_id, core_id, smt_id); +} + +#endif /* TARGET_I386_TOPOLOGY_H */ diff --git a/tests/.gitignore b/tests/.gitignore index f9041f3d32..38c94ef1da 100644 --- a/tests/.gitignore +++ b/tests/.gitignore @@ -10,4 +10,5 @@ test-qmp-commands.h test-qmp-commands test-qmp-input-strict test-qmp-marshal.c +test-x86-cpuid *-test diff --git a/tests/Makefile b/tests/Makefile index 442b286ccf..804ce42962 100644 --- a/tests/Makefile +++ b/tests/Makefile @@ -45,6 +45,9 @@ gcov-files-test-aio-$(CONFIG_WIN32) = aio-win32.c gcov-files-test-aio-$(CONFIG_POSIX) = aio-posix.c check-unit-y += tests/test-thread-pool$(EXESUF) gcov-files-test-thread-pool-y = thread-pool.c +check-unit-y += tests/test-x86-cpuid$(EXESUF) +# all code tested by test-x86-cpuid is inside topology.h +gcov-files-test-x86-cpuid-y = check-block-$(CONFIG_POSIX) += tests/qemu-iotests-quick.sh @@ -72,12 +75,15 @@ test-obj-y = tests/check-qint.o tests/check-qstring.o tests/check-qdict.o \ tests/test-coroutine.o tests/test-string-output-visitor.o \ tests/test-string-input-visitor.o tests/test-qmp-output-visitor.o \ tests/test-qmp-input-visitor.o tests/test-qmp-input-strict.o \ - tests/test-qmp-commands.o tests/test-visitor-serialization.o + tests/test-qmp-commands.o tests/test-visitor-serialization.o \ + tests/test-x86-cpuid.o test-qapi-obj-y = tests/test-qapi-visit.o tests/test-qapi-types.o $(test-obj-y): QEMU_INCLUDES += -Itests +tests/test-x86-cpuid.o: QEMU_INCLUDES += -I$(SRC_PATH)/target-i386 + tests/check-qint$(EXESUF): tests/check-qint.o libqemuutil.a tests/check-qstring$(EXESUF): tests/check-qstring.o libqemuutil.a tests/check-qdict$(EXESUF): tests/check-qdict.o libqemuutil.a @@ -88,6 +94,7 @@ tests/test-coroutine$(EXESUF): tests/test-coroutine.o $(block-obj-y) libqemuutil tests/test-aio$(EXESUF): tests/test-aio.o $(block-obj-y) libqemuutil.a libqemustub.a tests/test-thread-pool$(EXESUF): tests/test-thread-pool.o $(block-obj-y) libqemuutil.a libqemustub.a tests/test-iov$(EXESUF): tests/test-iov.o libqemuutil.a +tests/test-x86-cpuid$(EXESUF): tests/test-x86-cpuid.o tests/test-qapi-types.c tests/test-qapi-types.h :\ $(SRC_PATH)/qapi-schema-test.json $(SRC_PATH)/scripts/qapi-types.py diff --git a/tests/test-x86-cpuid.c b/tests/test-x86-cpuid.c new file mode 100644 index 0000000000..8d9f96a113 --- /dev/null +++ b/tests/test-x86-cpuid.c @@ -0,0 +1,110 @@ +/* + * Test code for x86 CPUID and Topology functions + * + * Copyright (c) 2012 Red Hat Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include + +#include "topology.h" + +static void test_topo_bits(void) +{ + /* simple tests for 1 thread per core, 1 core per socket */ + g_assert_cmpuint(apicid_smt_width(1, 1), ==, 0); + g_assert_cmpuint(apicid_core_width(1, 1), ==, 0); + + g_assert_cmpuint(x86_apicid_from_cpu_idx(1, 1, 0), ==, 0); + g_assert_cmpuint(x86_apicid_from_cpu_idx(1, 1, 1), ==, 1); + g_assert_cmpuint(x86_apicid_from_cpu_idx(1, 1, 2), ==, 2); + g_assert_cmpuint(x86_apicid_from_cpu_idx(1, 1, 3), ==, 3); + + + /* Test field width calculation for multiple values + */ + g_assert_cmpuint(apicid_smt_width(1, 2), ==, 1); + g_assert_cmpuint(apicid_smt_width(1, 3), ==, 2); + g_assert_cmpuint(apicid_smt_width(1, 4), ==, 2); + + g_assert_cmpuint(apicid_smt_width(1, 14), ==, 4); + g_assert_cmpuint(apicid_smt_width(1, 15), ==, 4); + g_assert_cmpuint(apicid_smt_width(1, 16), ==, 4); + g_assert_cmpuint(apicid_smt_width(1, 17), ==, 5); + + + g_assert_cmpuint(apicid_core_width(30, 2), ==, 5); + g_assert_cmpuint(apicid_core_width(31, 2), ==, 5); + g_assert_cmpuint(apicid_core_width(32, 2), ==, 5); + g_assert_cmpuint(apicid_core_width(33, 2), ==, 6); + + + /* build a weird topology and see if IDs are calculated correctly + */ + + /* This will use 2 bits for thread ID and 3 bits for core ID + */ + g_assert_cmpuint(apicid_smt_width(6, 3), ==, 2); + g_assert_cmpuint(apicid_core_width(6, 3), ==, 3); + g_assert_cmpuint(apicid_pkg_offset(6, 3), ==, 5); + + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 0), ==, 0); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 1), ==, 1); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 2), ==, 2); + + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 1 * 3 + 0), ==, + (1 << 2) | 0); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 1 * 3 + 1), ==, + (1 << 2) | 1); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 1 * 3 + 2), ==, + (1 << 2) | 2); + + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 2 * 3 + 0), ==, + (2 << 2) | 0); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 2 * 3 + 1), ==, + (2 << 2) | 1); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 2 * 3 + 2), ==, + (2 << 2) | 2); + + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 5 * 3 + 0), ==, + (5 << 2) | 0); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 5 * 3 + 1), ==, + (5 << 2) | 1); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 5 * 3 + 2), ==, + (5 << 2) | 2); + + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 1 * 6 * 3 + 0 * 3 + 0), ==, + (1 << 5)); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 1 * 6 * 3 + 1 * 3 + 1), ==, + (1 << 5) | (1 << 2) | 1); + g_assert_cmpuint(x86_apicid_from_cpu_idx(6, 3, 3 * 6 * 3 + 5 * 3 + 2), ==, + (3 << 5) | (5 << 2) | 2); +} + +int main(int argc, char **argv) +{ + g_test_init(&argc, &argv, NULL); + + g_test_add_func("/cpuid/topology/basic", test_topo_bits); + + g_test_run(); + + return 0; +} -- 2.11.0