^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Preempt / IRQ disable delay thread to test latency tracers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2018 Joel Fernandes (Google) <joel@joelfernandes.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/trace_clock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/interrupt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/irq.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/kobject.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/kthread.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/printk.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/sysfs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/completion.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) static ulong delay = 100;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) static char test_mode[12] = "irq";
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) static uint burst_size = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) module_param_named(delay, delay, ulong, 0444);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) module_param_string(test_mode, test_mode, 12, 0444);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) module_param_named(burst_size, burst_size, uint, 0444);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) MODULE_PARM_DESC(delay, "Period in microseconds (100 us default)");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) MODULE_PARM_DESC(test_mode, "Mode of the test such as preempt, irq, or alternate (default irq)");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) MODULE_PARM_DESC(burst_size, "The size of a burst (default 1)");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) static struct completion done;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #define MIN(x, y) ((x) < (y) ? (x) : (y))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) static void busy_wait(ulong time)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) u64 start, end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) start = trace_clock_local();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) end = trace_clock_local();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) if (kthread_should_stop())
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) } while ((end - start) < (time * 1000));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) static __always_inline void irqoff_test(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) local_irq_save(flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) busy_wait(delay);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) local_irq_restore(flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) static __always_inline void preemptoff_test(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) preempt_disable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) busy_wait(delay);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) preempt_enable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) static void execute_preemptirqtest(int idx)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) if (!strcmp(test_mode, "irq"))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) irqoff_test();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) else if (!strcmp(test_mode, "preempt"))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) preemptoff_test();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) else if (!strcmp(test_mode, "alternate")) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) if (idx % 2 == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) irqoff_test();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) preemptoff_test();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) #define DECLARE_TESTFN(POSTFIX) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) static void preemptirqtest_##POSTFIX(int idx) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) { \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) execute_preemptirqtest(idx); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) } \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) * We create 10 different functions, so that we can get 10 different
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) * backtraces.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) DECLARE_TESTFN(0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) DECLARE_TESTFN(1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) DECLARE_TESTFN(2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) DECLARE_TESTFN(3)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) DECLARE_TESTFN(4)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) DECLARE_TESTFN(5)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) DECLARE_TESTFN(6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) DECLARE_TESTFN(7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) DECLARE_TESTFN(8)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) DECLARE_TESTFN(9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) static void (*testfuncs[])(int) = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) preemptirqtest_0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) preemptirqtest_1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) preemptirqtest_2,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) preemptirqtest_3,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) preemptirqtest_4,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) preemptirqtest_5,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) preemptirqtest_6,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) preemptirqtest_7,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) preemptirqtest_8,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) preemptirqtest_9,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) #define NR_TEST_FUNCS ARRAY_SIZE(testfuncs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) static int preemptirq_delay_run(void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) int s = MIN(burst_size, NR_TEST_FUNCS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) for (i = 0; i < s; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) (testfuncs[i])(i);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) complete(&done);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) set_current_state(TASK_INTERRUPTIBLE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) while (!kthread_should_stop()) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) schedule();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) set_current_state(TASK_INTERRUPTIBLE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) __set_current_state(TASK_RUNNING);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) static int preemptirq_run_test(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) struct task_struct *task;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) char task_name[50];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) init_completion(&done);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) snprintf(task_name, sizeof(task_name), "%s_test", test_mode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) task = kthread_run(preemptirq_delay_run, NULL, task_name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) if (IS_ERR(task))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) return PTR_ERR(task);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) if (task) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) wait_for_completion(&done);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) kthread_stop(task);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) static ssize_t trigger_store(struct kobject *kobj, struct kobj_attribute *attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) const char *buf, size_t count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) ssize_t ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) ret = preemptirq_run_test();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) static struct kobj_attribute trigger_attribute =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) __ATTR(trigger, 0200, NULL, trigger_store);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) static struct attribute *attrs[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) &trigger_attribute.attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) static struct attribute_group attr_group = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) .attrs = attrs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) static struct kobject *preemptirq_delay_kobj;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) static int __init preemptirq_delay_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) int retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) retval = preemptirq_run_test();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) if (retval != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) preemptirq_delay_kobj = kobject_create_and_add("preemptirq_delay_test",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) kernel_kobj);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) if (!preemptirq_delay_kobj)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) retval = sysfs_create_group(preemptirq_delay_kobj, &attr_group);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) if (retval)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) kobject_put(preemptirq_delay_kobj);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) static void __exit preemptirq_delay_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) kobject_put(preemptirq_delay_kobj);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) module_init(preemptirq_delay_init)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) module_exit(preemptirq_delay_exit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) MODULE_LICENSE("GPL v2");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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