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endersonmaialneto
endersonmaia
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lneto
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add luacpu module
1 parent 8944dc3 commit d4cdb08

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4 files changed

+199
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4 files changed

+199
-2
lines changed

‎Kbuild‎

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@@ -52,4 +52,5 @@ obj-$(CONFIG_LUNATIK_CRYPTO_SKCIPHER) += lib/luacrypto_skcipher.o
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obj-$(CONFIG_LUNATIK_CRYPTO_AEAD) += lib/luacrypto_aead.o
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obj-$(CONFIG_LUNATIK_CRYPTO_RNG) += lib/luacrypto_rng.o
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obj-$(CONFIG_LUNATIK_CRYPTO_COMP) += lib/luacrypto_comp.o
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obj-$(CONFIG_LUNATIK_CPU) += lib/luacpu.o
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‎Makefile‎

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@@ -30,7 +30,7 @@ all: lunatik_sym.h
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CONFIG_LUNATIK_NETFILTER=m CONFIG_LUNATIK_COMPLETION=m \
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CONFIG_LUNATIK_CRYPTO_SHASH=m CONFIG_LUNATIK_CRYPTO_SKCIPHER=m \
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CONFIG_LUNATIK_CRYPTO_AEAD=m CONFIG_LUNATIK_CRYPTO_RNG=m \
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CONFIG_LUNATIK_CRYPTO_COMP=m
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CONFIG_LUNATIK_CRYPTO_COMP=m CONFIG_LUNATIK_CPU=m
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clean:
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${MAKE} -C ${MODULES_BUILD_PATH} M=${PWD} clean

‎bin/lunatik‎

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@@ -10,7 +10,7 @@ local lunatik = {
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modules = {"lunatik", "luadevice", "lualinux", "luanotifier", "luasocket", "luarcu",
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"luathread", "luafib", "luadata", "luaprobe", "luasyscall", "luaxdp", "luafifo", "luaxtable",
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"luanetfilter", "luacompletion", "luacrypto_shash", "luacrypto_skcipher", "luacrypto_aead",
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"luacrypto_rng", "luacrypto_comp", "lunatik_run"}
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"luacrypto_rng", "luacrypto_comp", "luacpu", "lunatik_run"},
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}
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function lunatik.prompt()

‎lib/luacpu.c‎

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@@ -0,0 +1,196 @@
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/*
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* SPDX-FileCopyrightText: (c) 2025 Enderson Maia <[email protected]
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* SPDX-License-Identifier: MIT OR GPL-2.0-only
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*/
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/***
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* Linux CPU Lua interface.
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*
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* This module provides access to Linux's CPU abstractions.
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*
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* @module cpu
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
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#include <linux/cpumask.h>
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#include <linux/kernel_stat.h>
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#include <lua.h>
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#include <lualib.h>
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#include <lauxlib.h>
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#include <lunatik.h>
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#define LUACPU_NUM(name) \
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static int luacpu_num_##name(lua_State *L) { \
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lua_pushinteger(L, (lua_Integer)num_##name##_cpus()); \
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return 1; \
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}
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/***
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* Returns the possible CPUs in the system.
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*
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* @function num_possible
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* @treturn integer The number of possible CPUs in the system
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*/
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LUACPU_NUM(possible)
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/***
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* Returns the possible CPUs in the system.
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*
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* @function num_possible
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* @treturn integer The number of possible CPUs in the system
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*/
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LUACPU_NUM(present)
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/***
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* Returns the possible CPUs in the system.
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*
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* @function num_possible
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* @treturn integer The number of possible CPUs in the system
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*/
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LUACPU_NUM(online)
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/***
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* Macro to set CPU statistics in Lua table.
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* @param L Lua state
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* @param idx Index of the table in the Lua stack
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* @param kcs Kernel CPU statistics structure (kernel_cpustat)
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* @param name Field name in the Lua table
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* @param NAME Corresponding C enum name for CPU time
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*/
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#define luacpu_setstat(L, idx, kcs, name, NAME) \
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do { \
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lua_pushinteger(L, (lua_Integer)kcs.cpustat[CPUTIME_##NAME]); \
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lua_setfield(L, idx - 1, #name); \
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} while (0)
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/***
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* Gets CPU statistics for a specific CPU.
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* Fetches kernel CPU statistics including user, nice, system, idle, iowait,
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* irq, softirq, steal, guest, guest_nice and forceidle times.
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*
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* @function stats
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* @tparam integer cpu The CPU number (0-based) to query.
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* @treturn table A table containing CPU time statistics with the following fields:
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* @tfield integer user Time spent in user mode
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* @tfield integer nice Time spent in user mode with low priority (nice)
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* @tfield integer system Time spent in system mode
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* @tfield integer idle Time spent in idle task
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* @tfield integer iowait Time waiting for I/O to complete
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* @tfield integer irq Time servicing hardware interrupts
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* @tfield integer softirq Time servicing software interrupts
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* @tfield integer steal Time stolen by other operating systems (virtualized environment)
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* @tfield integer guest Time spent running a virtual CPU for guest OS
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* @tfield integer guest_nice Time spent running a niced guest
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* @tfield integer forceidle Time spent in forced idle (if CONFIG_SCHED_CORE is enabled)
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* @raise Error if CPU is offline
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* @usage
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* local cpu0 = cpu.stats(0)
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* print("CPU 0 user time:", cpu0.user)
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* print("CPU 0 idle time:", cpu0.idle)
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*/
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static int luacpu_stats(lua_State *L)
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{
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unsigned int cpu = luaL_checkinteger(L, 1);
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struct kernel_cpustat kcs;
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luaL_argcheck(L, cpu_online(cpu), 1, "CPU is offline");
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kcpustat_cpu_fetch(&kcs, cpu);
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lua_createtable(L, 0, NR_STATS);
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luacpu_setstat(L, -1, kcs, user, USER);
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luacpu_setstat(L, -1, kcs, nice, NICE);
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luacpu_setstat(L, -1, kcs, system, SYSTEM);
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luacpu_setstat(L, -1, kcs, idle, IDLE);
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luacpu_setstat(L, -1, kcs, iowait, IOWAIT);
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luacpu_setstat(L, -1, kcs, irq, IRQ);
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luacpu_setstat(L, -1, kcs, softirq, SOFTIRQ);
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luacpu_setstat(L, -1, kcs, steal, STEAL);
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luacpu_setstat(L, -1, kcs, guest, GUEST);
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luacpu_setstat(L, -1, kcs, guest_nice, GUEST_NICE);
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#ifdef CONFIG_SCHED_CORE
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luacpu_setstat(L, -1, kcs, forceidle, FORCEIDLE);
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#endif
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return 1;
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}
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#define LUACPU_FOREACH(name) \
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static int luacpu_foreach_##name(lua_State *L) { \
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unsigned int cpu; \
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luaL_checktype(L, 1, LUA_TFUNCTION); \
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for_each_##name##_cpu(cpu) { \
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lua_pushvalue(L, 1); \
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lua_pushinteger(L, cpu); \
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lua_call(L, 1, 0); \
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} \
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return 0; \
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};
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/***
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* Iterates over all possible CPUs and calls a function for each.
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*
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* @function foreach_possible
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* @tparam function callback Function to call for each possible CPU
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* @usage
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* cpu.foreach_possible(function(cpu_num)
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* print("CPU", cpu.stats(cpu_num))
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* end)
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*/
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LUACPU_FOREACH(possible)
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/***
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* Iterates over all present CPUs and calls a function for each.
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*
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* @function foreach_present
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* @tparam function callback Function to call for each present CPU
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* @usage
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* cpu.foreach_present(function(cpu_num)
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* print("CPU", cpu.stats(cpu_num))
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* end)
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*/
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LUACPU_FOREACH(present)
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/***
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* Iterates over all online CPUs and calls a function for each.
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*
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* @function foreach_online
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* @tparam function callback Function to call for each online CPU
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* @usage
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* cpu.foreach_online(function(cpu_num)
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* print("CPU", cpu.stats(cpu_num))
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* end)
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*/
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LUACPU_FOREACH(online)
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static const luaL_Reg luacpu_lib[] = {
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{"num_possible", luacpu_num_possible},
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{"num_present", luacpu_num_present},
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{"num_online", luacpu_num_online},
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{"stats", luacpu_stats},
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{"foreach_possible", luacpu_foreach_possible},
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{"foreach_present", luacpu_foreach_present},
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{"foreach_online", luacpu_foreach_online},
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{NULL, NULL}
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};
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LUNATIK_NEWLIB(cpu, luacpu_lib, NULL, NULL);
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static int __init luacpu_init(void)
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{
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return 0;
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}
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static void __exit luacpu_exit(void)
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{
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}
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module_init(luacpu_init);
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module_exit(luacpu_exit);
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MODULE_LICENSE("Dual MIT/GPL");
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MODULE_AUTHOR("Enderson Maia <[email protected]");
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MODULE_DESCRIPTION("Lunatik interface to Linux's CPU abstractions.");
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