// SPDX-License-Identifier: GPL-2.0+/* * Common functions for in-kernel torture tests. * * Copyright (C) IBM Corporation, 2014 * * Author: Paul E. McKenney <paulmck@linux.ibm.com> * Based on kernel/rcu/torture.c. */ #define pr_fmt(fmt) fmt #include <linux/types.h>#include <linux/kernel.h>#include <linux/init.h>#include <linux/module.h>#include <linux/kthread.h>#include <linux/err.h>#include <linux/spinlock.h>#include <linux/smp.h>#include <linux/interrupt.h>#include <linux/sched.h>#include <linux/sched/clock.h>#include <linux/atomic.h>#include <linux/bitops.h>#include <linux/completion.h>#include <linux/moduleparam.h>#include <linux/percpu.h>#include <linux/notifier.h>#include <linux/reboot.h>#include <linux/freezer.h>#include <linux/cpu.h>#include <linux/delay.h>#include <linux/stat.h>#include <linux/slab.h>#include <linux/trace_clock.h>#include <linux/ktime.h>#include <asm/byteorder.h>#include <linux/torture.h>#include <linux/sched/rt.h>#include "rcu/rcu.h" MODULE_DESCRIPTION("Common functions for in-kernel torture tests");MODULE_LICENSE("GPL");MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>"); static bool disable_onoff_at_boot;module_param(disable_onoff_at_boot, bool, 0444); static bool ftrace_dump_at_shutdown;module_param(ftrace_dump_at_shutdown, bool, 0444); static int verbose_sleep_frequency;module_param(verbose_sleep_frequency, int, 0444); static int verbose_sleep_duration = 1;module_param(verbose_sleep_duration, int, 0444); static int random_shuffle;module_param(random_shuffle, int, 0444); static char *torture_type;static int verbose; /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */#define FULLSTOP_DONTSTOP 0 /* Normal operation. */#define FULLSTOP_SHUTDOWN 1 /* System shutdown with torture running. */#define FULLSTOP_RMMOD 2 /* Normal rmmod of torture. */static int fullstop = FULLSTOP_RMMOD;static DEFINE_MUTEX(fullstop_mutex); static atomic_t verbose_sleep_counter; /* * Sleep if needed from VERBOSE_TOROUT*(). */void verbose_torout_sleep(void){ if (verbose_sleep_frequency > 0 && verbose_sleep_duration > 0 && !(atomic_inc_return(&verbose_sleep_counter) % verbose_sleep_frequency)) schedule_timeout_uninterruptible(verbose_sleep_duration);}EXPORT_SYMBOL_GPL(verbose_torout_sleep); /* * Schedule a high-resolution-timer sleep in nanoseconds, with a 32-bit * nanosecond random fuzz. This function and its friends desynchronize * testing from the timer wheel. */int torture_hrtimeout_ns(ktime_t baset_ns, u32 fuzzt_ns, const enum hrtimer_mode mode, struct torture_random_state *trsp){ ktime_t hto = baset_ns; if (trsp) hto += torture_random(trsp) % fuzzt_ns; set_current_state(TASK_IDLE); return schedule_hrtimeout(&hto, mode);}EXPORT_SYMBOL_GPL(torture_hrtimeout_ns); /* * Schedule a high-resolution-timer sleep in microseconds, with a 32-bit * nanosecond (not microsecond!) random fuzz. */int torture_hrtimeout_us(u32 baset_us, u32 fuzzt_ns, struct torture_random_state *trsp){ ktime_t baset_ns = baset_us * NSEC_PER_USEC; return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);}EXPORT_SYMBOL_GPL(torture_hrtimeout_us); /* * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit * microsecond (not millisecond!) random fuzz. */int torture_hrtimeout_ms(u32 baset_ms, u32 fuzzt_us, struct torture_random_state *trsp){ ktime_t baset_ns = baset_ms * NSEC_PER_MSEC; u32 fuzzt_ns; if ((u32)~0U / NSEC_PER_USEC < fuzzt_us) fuzzt_ns = (u32)~0U; else fuzzt_ns = fuzzt_us * NSEC_PER_USEC; return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);}EXPORT_SYMBOL_GPL(torture_hrtimeout_ms); /* * Schedule a high-resolution-timer sleep in jiffies, with an * implied one-jiffy random fuzz. This is intended to replace calls to * schedule_timeout_interruptible() and friends. */int torture_hrtimeout_jiffies(u32 baset_j, struct torture_random_state *trsp){ ktime_t baset_ns = jiffies_to_nsecs(baset_j); return torture_hrtimeout_ns(baset_ns, jiffies_to_nsecs(1), HRTIMER_MODE_REL, trsp);}EXPORT_SYMBOL_GPL(torture_hrtimeout_jiffies); /* * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit * millisecond (not second!) random fuzz. */int torture_hrtimeout_s(u32 baset_s, u32 fuzzt_ms, struct torture_random_state *trsp){ ktime_t baset_ns = baset_s * NSEC_PER_SEC; u32 fuzzt_ns; if ((u32)~0U / NSEC_PER_MSEC < fuzzt_ms) fuzzt_ns = (u32)~0U; else fuzzt_ns = fuzzt_ms * NSEC_PER_MSEC; return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);}EXPORT_SYMBOL_GPL(torture_hrtimeout_s); #ifdef CONFIG_HOTPLUG_CPU /* * Variables for online-offline handling. Only present if CPU hotplug * is enabled, otherwise does nothing. */ static struct task_struct *onoff_task;static long onoff_holdoff;static long onoff_interval;static torture_ofl_func *onoff_f;static long n_offline_attempts;static long n_offline_successes;static unsigned long sum_offline;static int min_offline = -1;static int max_offline;static long n_online_attempts;static long n_online_successes;static unsigned long sum_online;static int min_online = -1;static int max_online; static int torture_online_cpus = NR_CPUS; /* * Some torture testing leverages confusion as to the number of online * CPUs. This function returns the torture-testing view of this number, * which allows torture tests to load-balance appropriately. */int torture_num_online_cpus(void){ return READ_ONCE(torture_online_cpus);}EXPORT_SYMBOL_GPL(torture_num_online_cpus); /* * Attempt to take a CPU offline. Return false if the CPU is already * offline or if it is not subject to CPU-hotplug operations. The * caller can detect other failures by looking at the statistics. */bool torture_offline(int cpu, long *n_offl_attempts, long *n_offl_successes, unsigned long *sum_offl, int *min_offl, int *max_offl){ unsigned long delta; int ret; char *s; unsigned long starttime; if (!cpu_online(cpu) || !cpu_is_hotpluggable(cpu)) return false; if (num_online_cpus() <= 1) return false; /* Can't offline the last CPU. */ if (verbose > 1) pr_alert("%s" TORTURE_FLAG "torture_onoff task: offlining %d\n", torture_type, cpu); starttime = jiffies; (*n_offl_attempts)++; ret = remove_cpu(cpu); if (ret) { s = ""; if (!rcu_inkernel_boot_has_ended() && ret == -EBUSY) { // PCI probe frequently disables hotplug during boot. (*n_offl_attempts)--; s = " (-EBUSY forgiven during boot)"; } if (verbose) pr_alert("%s" TORTURE_FLAG "torture_onoff task: offline %d failed%s: errno %d\n", torture_type, cpu, s, ret); } else { if (verbose > 1) pr_alert("%s" TORTURE_FLAG "torture_onoff task: offlined %d\n", torture_type, cpu); if (onoff_f) onoff_f(); (*n_offl_successes)++; delta = jiffies - starttime; *sum_offl += delta; if (*min_offl < 0) { *min_offl = delta; *max_offl = delta; } if (*min_offl > delta) *min_offl = delta; if (*max_offl < delta) *max_offl = delta; WRITE_ONCE(torture_online_cpus, torture_online_cpus - 1); WARN_ON_ONCE(torture_online_cpus <= 0); } return true;}EXPORT_SYMBOL_GPL(torture_offline); /* * Attempt to bring a CPU online. Return false if the CPU is already * online or if it is not subject to CPU-hotplug operations. The * caller can detect other failures by looking at the statistics. */bool torture_online(int cpu, long *n_onl_attempts, long *n_onl_successes, unsigned long *sum_onl, int *min_onl, int *max_onl){ unsigned long delta; int ret; char *s; unsigned long starttime; if (cpu_online(cpu) || !cpu_is_hotpluggable(cpu)) return false; if (verbose > 1) pr_alert("%s" TORTURE_FLAG "torture_onoff task: onlining %d\n", torture_type, cpu); starttime = jiffies; (*n_onl_attempts)++; ret = add_cpu(cpu); if (ret) { s = ""; if (!rcu_inkernel_boot_has_ended() && ret == -EBUSY) { // PCI probe frequently disables hotplug during boot. (*n_onl_attempts)--; s = " (-EBUSY forgiven during boot)"; } if (verbose) pr_alert("%s" TORTURE_FLAG "torture_onoff task: online %d failed%s: errno %d\n", torture_type, cpu, s, ret); } else { if (verbose > 1) pr_alert("%s" TORTURE_FLAG "torture_onoff task: onlined %d\n", torture_type, cpu); (*n_onl_successes)++; delta = jiffies - starttime; *sum_onl += delta; if (*min_onl < 0) { *min_onl = delta; *max_onl = delta; } if (*min_onl > delta) *min_onl = delta; if (*max_onl < delta) *max_onl = delta; WRITE_ONCE(torture_online_cpus, torture_online_cpus + 1); } return true;}EXPORT_SYMBOL_GPL(torture_online); /* * Get everything online at the beginning and ends of tests. */static void torture_online_all(char *phase){ int cpu; int ret; for_each_possible_cpu(cpu) { if (cpu_online(cpu)) continue; ret = add_cpu(cpu); if (ret && verbose) { pr_alert("%s" TORTURE_FLAG "%s: %s online %d: errno %d\n", __func__, phase, torture_type, cpu, ret); } }} /* * Execute random CPU-hotplug operations at the interval specified * by the onoff_interval. */static inttorture_onoff(void *arg){ int cpu; int maxcpu = -1; DEFINE_TORTURE_RANDOM(rand); VERBOSE_TOROUT_STRING("torture_onoff task started"); for_each_online_cpu(cpu) maxcpu = cpu; WARN_ON(maxcpu < 0); torture_online_all("Initial"); if (maxcpu == 0) { VERBOSE_TOROUT_STRING("Only one CPU, so CPU-hotplug testing is disabled"); goto stop; } if (onoff_holdoff > 0) { VERBOSE_TOROUT_STRING("torture_onoff begin holdoff"); torture_hrtimeout_jiffies(onoff_holdoff, &rand); VERBOSE_TOROUT_STRING("torture_onoff end holdoff"); } while (!torture_must_stop()) { if (disable_onoff_at_boot && !rcu_inkernel_boot_has_ended()) { torture_hrtimeout_jiffies(HZ / 10, &rand); continue; } cpu = torture_random(&rand) % (maxcpu + 1); if (!torture_offline(cpu, &n_offline_attempts, &n_offline_successes, &sum_offline, &min_offline, &max_offline)) torture_online(cpu, &n_online_attempts, &n_online_successes, &sum_online, &min_online, &max_online); torture_hrtimeout_jiffies(onoff_interval, &rand); } stop: torture_kthread_stopping("torture_onoff"); torture_online_all("Final"); return 0;} #endif /* #ifdef CONFIG_HOTPLUG_CPU */ /* * Initiate online-offline handling. */int torture_onoff_init(long ooholdoff, long oointerval, torture_ofl_func *f){#ifdef CONFIG_HOTPLUG_CPU onoff_holdoff = ooholdoff; onoff_interval = oointerval; onoff_f = f; if (onoff_interval <= 0) return 0; return torture_create_kthread(torture_onoff, NULL, onoff_task);#else /* #ifdef CONFIG_HOTPLUG_CPU */ return 0;#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */}EXPORT_SYMBOL_GPL(torture_onoff_init); /* * Clean up after online/offline testing. */static void torture_onoff_cleanup(void){#ifdef CONFIG_HOTPLUG_CPU if (onoff_task == NULL) return; VERBOSE_TOROUT_STRING("Stopping torture_onoff task"); kthread_stop(onoff_task); onoff_task = NULL;#endif /* #ifdef CONFIG_HOTPLUG_CPU */} /* * Print online/offline testing statistics. */void torture_onoff_stats(void){#ifdef CONFIG_HOTPLUG_CPU pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ", n_online_successes, n_online_attempts, n_offline_successes, n_offline_attempts, min_online, max_online, min_offline, max_offline, sum_online, sum_offline, HZ);#endif /* #ifdef CONFIG_HOTPLUG_CPU */}EXPORT_SYMBOL_GPL(torture_onoff_stats); /* * Were all the online/offline operations successful? */bool torture_onoff_failures(void){#ifdef CONFIG_HOTPLUG_CPU return n_online_successes != n_online_attempts || n_offline_successes != n_offline_attempts;#else /* #ifdef CONFIG_HOTPLUG_CPU */ return false;#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */}EXPORT_SYMBOL_GPL(torture_onoff_failures); #define TORTURE_RANDOM_MULT 39916801 /* prime */#define TORTURE_RANDOM_ADD 479001701 /* prime */#define TORTURE_RANDOM_REFRESH 10000 /* * Crude but fast random-number generator. Uses a linear congruential * generator, with occasional help from cpu_clock(). */unsigned longtorture_random(struct torture_random_state *trsp){ if (--trsp->trs_count < 0) { trsp->trs_state += (unsigned long)local_clock() + raw_smp_processor_id(); trsp->trs_count = TORTURE_RANDOM_REFRESH; } trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT + TORTURE_RANDOM_ADD; return swahw32(trsp->trs_state);}EXPORT_SYMBOL_GPL(torture_random); /* * Variables for shuffling. The idea is to ensure that each CPU stays * idle for an extended period to test interactions with dyntick idle, * as well as interactions with any per-CPU variables. */struct shuffle_task { struct list_head st_l; struct task_struct *st_t;}; static long shuffle_interval; /* In jiffies. */static struct task_struct *shuffler_task;static cpumask_var_t shuffle_tmp_mask;static int shuffle_idle_cpu; /* Force all torture tasks off this CPU */static struct list_head shuffle_task_list = LIST_HEAD_INIT(shuffle_task_list);static DEFINE_MUTEX(shuffle_task_mutex); /* * Register a task to be shuffled. If there is no memory, just splat * and don't bother registering. */void torture_shuffle_task_register(struct task_struct *tp){ struct shuffle_task *stp; if (WARN_ON_ONCE(tp == NULL)) return; stp = kmalloc(sizeof(*stp), GFP_KERNEL); if (WARN_ON_ONCE(stp == NULL)) return; stp->st_t = tp; mutex_lock(&shuffle_task_mutex); list_add(&stp->st_l, &shuffle_task_list);Lines 1–500 of 959. Load more
// SPDX-License-Identifier: GPL-2.0+ /* * Common functions for in-kernel torture tests. * * Copyright (C) IBM Corporation, 2014 * * Author: Paul E. McKenney <paulmck@linux.ibm.com> * Based on kernel/rcu/torture.c. */ #define pr_fmt(fmt) fmt #include <linux/types.h> #include <linux/kernel.h> #include <linux/init.h> #include <linux/module.h> #include <linux/kthread.h> #include <linux/err.h> #include <linux/spinlock.h> #include <linux/smp.h> #include <linux/interrupt.h> #include <linux/sched.h> #include <linux/sched/clock.h> #include <linux/atomic.h> #include <linux/bitops.h> #include <linux/completion.h> #include <linux/moduleparam.h> #include <linux/percpu.h> #include <linux/notifier.h> #include <linux/reboot.h> #include <linux/freezer.h> #include <linux/cpu.h> #include <linux/delay.h> #include <linux/stat.h> #include <linux/slab.h> #include <linux/trace_clock.h> #include <linux/ktime.h> #include <asm/byteorder.h> #include <linux/torture.h> #include <linux/sched/rt.h> #include "rcu/rcu.h" MODULE_DESCRIPTION("Common functions for in-kernel torture tests"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>"); static bool disable_onoff_at_boot; module_param(disable_onoff_at_boot, bool, 0444); static bool ftrace_dump_at_shutdown; module_param(ftrace_dump_at_shutdown, bool, 0444); static int verbose_sleep_frequency; module_param(verbose_sleep_frequency, int, 0444); static int verbose_sleep_duration = 1; module_param(verbose_sleep_duration, int, 0444); static int random_shuffle; module_param(random_shuffle, int, 0444); static char *torture_type; static int verbose; /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ #define FULLSTOP_DONTSTOP 0 /* Normal operation. */ #define FULLSTOP_SHUTDOWN 1 /* System shutdown with torture running. */ #define FULLSTOP_RMMOD 2 /* Normal rmmod of torture. */ static int fullstop = FULLSTOP_RMMOD; static DEFINE_MUTEX(fullstop_mutex); static atomic_t verbose_sleep_counter; /* * Sleep if needed from VERBOSE_TOROUT*(). */ void verbose_torout_sleep(void) { if (verbose_sleep_frequency > 0 && verbose_sleep_duration > 0 && !(atomic_inc_return(&verbose_sleep_counter) % verbose_sleep_frequency)) schedule_timeout_uninterruptible(verbose_sleep_duration); } EXPORT_SYMBOL_GPL(verbose_torout_sleep); /* * Schedule a high-resolution-timer sleep in nanoseconds, with a 32-bit * nanosecond random fuzz. This function and its friends desynchronize * testing from the timer wheel. */ int torture_hrtimeout_ns(ktime_t baset_ns, u32 fuzzt_ns, const enum hrtimer_mode mode, struct torture_random_state *trsp) { ktime_t hto = baset_ns; if (trsp) hto += torture_random(trsp) % fuzzt_ns; set_current_state(TASK_IDLE); return schedule_hrtimeout(&hto, mode); } EXPORT_SYMBOL_GPL(torture_hrtimeout_ns); /* * Schedule a high-resolution-timer sleep in microseconds, with a 32-bit * nanosecond (not microsecond!) random fuzz. */ int torture_hrtimeout_us(u32 baset_us, u32 fuzzt_ns, struct torture_random_state *trsp) { ktime_t baset_ns = baset_us * NSEC_PER_USEC; return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp); } EXPORT_SYMBOL_GPL(torture_hrtimeout_us); /* * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit * microsecond (not millisecond!) random fuzz. */ int torture_hrtimeout_ms(u32 baset_ms, u32 fuzzt_us, struct torture_random_state *trsp) { ktime_t baset_ns = baset_ms * NSEC_PER_MSEC; u32 fuzzt_ns; if ((u32)~0U / NSEC_PER_USEC < fuzzt_us) fuzzt_ns = (u32)~0U; else fuzzt_ns = fuzzt_us * NSEC_PER_USEC; return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp); } EXPORT_SYMBOL_GPL(torture_hrtimeout_ms); /* * Schedule a high-resolution-timer sleep in jiffies, with an * implied one-jiffy random fuzz. This is intended to replace calls to * schedule_timeout_interruptible() and friends. */ int torture_hrtimeout_jiffies(u32 baset_j, struct torture_random_state *trsp) { ktime_t baset_ns = jiffies_to_nsecs(baset_j); return torture_hrtimeout_ns(baset_ns, jiffies_to_nsecs(1), HRTIMER_MODE_REL, trsp); } EXPORT_SYMBOL_GPL(torture_hrtimeout_jiffies); /* * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit * millisecond (not second!) random fuzz. */ int torture_hrtimeout_s(u32 baset_s, u32 fuzzt_ms, struct torture_random_state *trsp) { ktime_t baset_ns = baset_s * NSEC_PER_SEC; u32 fuzzt_ns; if ((u32)~0U / NSEC_PER_MSEC < fuzzt_ms) fuzzt_ns = (u32)~0U; else fuzzt_ns = fuzzt_ms * NSEC_PER_MSEC; return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp); } EXPORT_SYMBOL_GPL(torture_hrtimeout_s); #ifdef CONFIG_HOTPLUG_CPU /* * Variables for online-offline handling. Only present if CPU hotplug * is enabled, otherwise does nothing. */ static struct task_struct *onoff_task; static long onoff_holdoff; static long onoff_interval; static torture_ofl_func *onoff_f; static long n_offline_attempts; static long n_offline_successes; static unsigned long sum_offline; static int min_offline = -1; static int max_offline; static long n_online_attempts; static long n_online_successes; static unsigned long sum_online; static int min_online = -1; static int max_online; static int torture_online_cpus = NR_CPUS; /* * Some torture testing leverages confusion as to the number of online * CPUs. This function returns the torture-testing view of this number, * which allows torture tests to load-balance appropriately. */ int torture_num_online_cpus(void) { return READ_ONCE(torture_online_cpus); } EXPORT_SYMBOL_GPL(torture_num_online_cpus); /* * Attempt to take a CPU offline. Return false if the CPU is already * offline or if it is not subject to CPU-hotplug operations. The * caller can detect other failures by looking at the statistics. */ bool torture_offline(int cpu, long *n_offl_attempts, long *n_offl_successes, unsigned long *sum_offl, int *min_offl, int *max_offl) { unsigned long delta; int ret; char *s; unsigned long starttime; if (!cpu_online(cpu) || !cpu_is_hotpluggable(cpu)) return false; if (num_online_cpus() <= 1) return false; /* Can't offline the last CPU. */ if (verbose > 1) pr_alert("%s" TORTURE_FLAG "torture_onoff task: offlining %d\n", torture_type, cpu); starttime = jiffies; (*n_offl_attempts)++; ret = remove_cpu(cpu); if (ret) { s = ""; if (!rcu_inkernel_boot_has_ended() && ret == -EBUSY) { // PCI probe frequently disables hotplug during boot. (*n_offl_attempts)--; s = " (-EBUSY forgiven during boot)"; } if (verbose) pr_alert("%s" TORTURE_FLAG "torture_onoff task: offline %d failed%s: errno %d\n", torture_type, cpu, s, ret); } else { if (verbose > 1) pr_alert("%s" TORTURE_FLAG "torture_onoff task: offlined %d\n", torture_type, cpu); if (onoff_f) onoff_f(); (*n_offl_successes)++; delta = jiffies - starttime; *sum_offl += delta; if (*min_offl < 0) { *min_offl = delta; *max_offl = delta; } if (*min_offl > delta) *min_offl = delta; if (*max_offl < delta) *max_offl = delta; WRITE_ONCE(torture_online_cpus, torture_online_cpus - 1); WARN_ON_ONCE(torture_online_cpus <= 0); } return true; } EXPORT_SYMBOL_GPL(torture_offline); /* * Attempt to bring a CPU online. Return false if the CPU is already * online or if it is not subject to CPU-hotplug operations. The * caller can detect other failures by looking at the statistics. */ bool torture_online(int cpu, long *n_onl_attempts, long *n_onl_successes, unsigned long *sum_onl, int *min_onl, int *max_onl) { unsigned long delta; int ret; char *s; unsigned long starttime; if (cpu_online(cpu) || !cpu_is_hotpluggable(cpu)) return false; if (verbose > 1) pr_alert("%s" TORTURE_FLAG "torture_onoff task: onlining %d\n", torture_type, cpu); starttime = jiffies; (*n_onl_attempts)++; ret = add_cpu(cpu); if (ret) { s = ""; if (!rcu_inkernel_boot_has_ended() && ret == -EBUSY) { // PCI probe frequently disables hotplug during boot. (*n_onl_attempts)--; s = " (-EBUSY forgiven during boot)"; } if (verbose) pr_alert("%s" TORTURE_FLAG "torture_onoff task: online %d failed%s: errno %d\n", torture_type, cpu, s, ret); } else { if (verbose > 1) pr_alert("%s" TORTURE_FLAG "torture_onoff task: onlined %d\n", torture_type, cpu); (*n_onl_successes)++; delta = jiffies - starttime; *sum_onl += delta; if (*min_onl < 0) { *min_onl = delta; *max_onl = delta; } if (*min_onl > delta) *min_onl = delta; if (*max_onl < delta) *max_onl = delta; WRITE_ONCE(torture_online_cpus, torture_online_cpus + 1); } return true; } EXPORT_SYMBOL_GPL(torture_online); /* * Get everything online at the beginning and ends of tests. */ static void torture_online_all(char *phase) { int cpu; int ret; for_each_possible_cpu(cpu) { if (cpu_online(cpu)) continue; ret = add_cpu(cpu); if (ret && verbose) { pr_alert("%s" TORTURE_FLAG "%s: %s online %d: errno %d\n", __func__, phase, torture_type, cpu, ret); } } } /* * Execute random CPU-hotplug operations at the interval specified * by the onoff_interval. */ static int torture_onoff(void *arg) { int cpu; int maxcpu = -1; DEFINE_TORTURE_RANDOM(rand); VERBOSE_TOROUT_STRING("torture_onoff task started"); for_each_online_cpu(cpu) maxcpu = cpu; WARN_ON(maxcpu < 0); torture_online_all("Initial"); if (maxcpu == 0) { VERBOSE_TOROUT_STRING("Only one CPU, so CPU-hotplug testing is disabled"); goto stop; } if (onoff_holdoff > 0) { VERBOSE_TOROUT_STRING("torture_onoff begin holdoff"); torture_hrtimeout_jiffies(onoff_holdoff, &rand); VERBOSE_TOROUT_STRING("torture_onoff end holdoff"); } while (!torture_must_stop()) { if (disable_onoff_at_boot && !rcu_inkernel_boot_has_ended()) { torture_hrtimeout_jiffies(HZ / 10, &rand); continue; } cpu = torture_random(&rand) % (maxcpu + 1); if (!torture_offline(cpu, &n_offline_attempts, &n_offline_successes, &sum_offline, &min_offline, &max_offline)) torture_online(cpu, &n_online_attempts, &n_online_successes, &sum_online, &min_online, &max_online); torture_hrtimeout_jiffies(onoff_interval, &rand); } stop: torture_kthread_stopping("torture_onoff"); torture_online_all("Final"); return 0; } #endif /* #ifdef CONFIG_HOTPLUG_CPU */ /* * Initiate online-offline handling. */ int torture_onoff_init(long ooholdoff, long oointerval, torture_ofl_func *f) { #ifdef CONFIG_HOTPLUG_CPU onoff_holdoff = ooholdoff; onoff_interval = oointerval; onoff_f = f; if (onoff_interval <= 0) return 0; return torture_create_kthread(torture_onoff, NULL, onoff_task); #else /* #ifdef CONFIG_HOTPLUG_CPU */ return 0; #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ } EXPORT_SYMBOL_GPL(torture_onoff_init); /* * Clean up after online/offline testing. */ static void torture_onoff_cleanup(void) { #ifdef CONFIG_HOTPLUG_CPU if (onoff_task == NULL) return; VERBOSE_TOROUT_STRING("Stopping torture_onoff task"); kthread_stop(onoff_task); onoff_task = NULL; #endif /* #ifdef CONFIG_HOTPLUG_CPU */ } /* * Print online/offline testing statistics. */ void torture_onoff_stats(void) { #ifdef CONFIG_HOTPLUG_CPU pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ", n_online_successes, n_online_attempts, n_offline_successes, n_offline_attempts, min_online, max_online, min_offline, max_offline, sum_online, sum_offline, HZ); #endif /* #ifdef CONFIG_HOTPLUG_CPU */ } EXPORT_SYMBOL_GPL(torture_onoff_stats); /* * Were all the online/offline operations successful? */ bool torture_onoff_failures(void) { #ifdef CONFIG_HOTPLUG_CPU return n_online_successes != n_online_attempts || n_offline_successes != n_offline_attempts; #else /* #ifdef CONFIG_HOTPLUG_CPU */ return false; #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ } EXPORT_SYMBOL_GPL(torture_onoff_failures); #define TORTURE_RANDOM_MULT 39916801 /* prime */ #define TORTURE_RANDOM_ADD 479001701 /* prime */ #define TORTURE_RANDOM_REFRESH 10000 /* * Crude but fast random-number generator. Uses a linear congruential * generator, with occasional help from cpu_clock(). */ unsigned long torture_random(struct torture_random_state *trsp) { if (--trsp->trs_count < 0) { trsp->trs_state += (unsigned long)local_clock() + raw_smp_processor_id(); trsp->trs_count = TORTURE_RANDOM_REFRESH; } trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT + TORTURE_RANDOM_ADD; return swahw32(trsp->trs_state); } EXPORT_SYMBOL_GPL(torture_random); /* * Variables for shuffling. The idea is to ensure that each CPU stays * idle for an extended period to test interactions with dyntick idle, * as well as interactions with any per-CPU variables. */ struct shuffle_task { struct list_head st_l; struct task_struct *st_t; }; static long shuffle_interval; /* In jiffies. */ static struct task_struct *shuffler_task; static cpumask_var_t shuffle_tmp_mask; static int shuffle_idle_cpu; /* Force all torture tasks off this CPU */ static struct list_head shuffle_task_list = LIST_HEAD_INIT(shuffle_task_list); static DEFINE_MUTEX(shuffle_task_mutex); /* * Register a task to be shuffled. If there is no memory, just splat * and don't bother registering. */ void torture_shuffle_task_register(struct task_struct *tp) { struct shuffle_task *stp; if (WARN_ON_ONCE(tp == NULL)) return; stp = kmalloc(sizeof(*stp), GFP_KERNEL); if (WARN_ON_ONCE(stp == NULL)) return; stp->st_t = tp; mutex_lock(&shuffle_task_mutex); list_add(&stp->st_l, &shuffle_task_list);