| /* |
| * Spinlock test |
| * |
| * This code is based on code from the tcg_baremetal_tests. |
| * |
| * Copyright (C) 2015 Virtual Open Systems SAS |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <libcflat.h> |
| #include <asm/smp.h> |
| #include <asm/cpumask.h> |
| #include <asm/barrier.h> |
| |
| #define LOOP_SIZE 10000000 |
| |
| struct lock_ops { |
| void (*lock)(int *v); |
| void (*unlock)(int *v); |
| }; |
| static struct lock_ops lock_ops; |
| |
| static void gcc_builtin_lock(int *lock_var) |
| { |
| while (__sync_lock_test_and_set(lock_var, 1)); |
| } |
| static void gcc_builtin_unlock(int *lock_var) |
| { |
| __sync_lock_release(lock_var); |
| } |
| static void none_lock(int *lock_var) |
| { |
| while (*(volatile int *)lock_var != 0); |
| *(volatile int *)lock_var = 1; |
| } |
| static void none_unlock(int *lock_var) |
| { |
| *(volatile int *)lock_var = 0; |
| } |
| |
| static int global_a, global_b; |
| static int global_lock; |
| |
| static cpumask_t smp_test_complete; |
| |
| static void test_spinlock(void) |
| { |
| int i, errors = 0; |
| int cpu = smp_processor_id(); |
| |
| printf("CPU%d online\n", cpu); |
| |
| for (i = 0; i < LOOP_SIZE; i++) { |
| |
| lock_ops.lock(&global_lock); |
| |
| if (global_a == (cpu + 1) % 2) { |
| global_a = 1; |
| global_b = 0; |
| } else { |
| global_a = 0; |
| global_b = 1; |
| } |
| |
| if (global_a == global_b) |
| errors++; |
| |
| lock_ops.unlock(&global_lock); |
| } |
| report("CPU%d: Done - Errors: %d", errors == 0, cpu, errors); |
| |
| cpumask_set_cpu(cpu, &smp_test_complete); |
| if (cpu != 0) |
| halt(); |
| } |
| |
| int main(int argc, char **argv) |
| { |
| int cpu; |
| |
| if (argc > 1 && strcmp(argv[1], "bad") != 0) { |
| lock_ops.lock = gcc_builtin_lock; |
| lock_ops.unlock = gcc_builtin_unlock; |
| } else { |
| lock_ops.lock = none_lock; |
| lock_ops.unlock = none_unlock; |
| } |
| |
| for_each_present_cpu(cpu) { |
| if (cpu == 0) |
| continue; |
| smp_boot_secondary(cpu, test_spinlock); |
| } |
| |
| test_spinlock(); |
| |
| while (!cpumask_full(&smp_test_complete)) |
| cpu_relax(); |
| |
| return report_summary(); |
| } |