| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Read-Copy Update module-based scalability-test facility |
| * |
| * Copyright (C) IBM Corporation, 2015 |
| * |
| * Authors: Paul E. McKenney <paulmck@linux.ibm.com> |
| */ |
| |
| #define pr_fmt(fmt) fmt |
| |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/mm.h> |
| #include <linux/module.h> |
| #include <linux/kthread.h> |
| #include <linux/err.h> |
| #include <linux/spinlock.h> |
| #include <linux/smp.h> |
| #include <linux/rcupdate.h> |
| #include <linux/interrupt.h> |
| #include <linux/sched.h> |
| #include <uapi/linux/sched/types.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/srcu.h> |
| #include <linux/slab.h> |
| #include <asm/byteorder.h> |
| #include <linux/torture.h> |
| #include <linux/vmalloc.h> |
| #include <linux/rcupdate_trace.h> |
| |
| #include "rcu.h" |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>"); |
| |
| #define SCALE_FLAG "-scale:" |
| #define SCALEOUT_STRING(s) \ |
| pr_alert("%s" SCALE_FLAG " %s\n", scale_type, s) |
| #define VERBOSE_SCALEOUT_STRING(s) \ |
| do { if (verbose) pr_alert("%s" SCALE_FLAG " %s\n", scale_type, s); } while (0) |
| #define SCALEOUT_ERRSTRING(s) \ |
| pr_alert("%s" SCALE_FLAG "!!! %s\n", scale_type, s) |
| |
| /* |
| * The intended use cases for the nreaders and nwriters module parameters |
| * are as follows: |
| * |
| * 1. Specify only the nr_cpus kernel boot parameter. This will |
| * set both nreaders and nwriters to the value specified by |
| * nr_cpus for a mixed reader/writer test. |
| * |
| * 2. Specify the nr_cpus kernel boot parameter, but set |
| * rcuscale.nreaders to zero. This will set nwriters to the |
| * value specified by nr_cpus for an update-only test. |
| * |
| * 3. Specify the nr_cpus kernel boot parameter, but set |
| * rcuscale.nwriters to zero. This will set nreaders to the |
| * value specified by nr_cpus for a read-only test. |
| * |
| * Various other use cases may of course be specified. |
| * |
| * Note that this test's readers are intended only as a test load for |
| * the writers. The reader scalability statistics will be overly |
| * pessimistic due to the per-critical-section interrupt disabling, |
| * test-end checks, and the pair of calls through pointers. |
| */ |
| |
| #ifdef MODULE |
| # define RCUSCALE_SHUTDOWN 0 |
| #else |
| # define RCUSCALE_SHUTDOWN 1 |
| #endif |
| |
| torture_param(bool, gp_async, false, "Use asynchronous GP wait primitives"); |
| torture_param(int, gp_async_max, 1000, "Max # outstanding waits per reader"); |
| torture_param(bool, gp_exp, false, "Use expedited GP wait primitives"); |
| torture_param(int, holdoff, 10, "Holdoff time before test start (s)"); |
| torture_param(int, nreaders, -1, "Number of RCU reader threads"); |
| torture_param(int, nwriters, -1, "Number of RCU updater threads"); |
| torture_param(bool, shutdown, RCUSCALE_SHUTDOWN, |
| "Shutdown at end of scalability tests."); |
| torture_param(int, verbose, 1, "Enable verbose debugging printk()s"); |
| torture_param(int, writer_holdoff, 0, "Holdoff (us) between GPs, zero to disable"); |
| torture_param(int, kfree_rcu_test, 0, "Do we run a kfree_rcu() scale test?"); |
| torture_param(int, kfree_mult, 1, "Multiple of kfree_obj size to allocate."); |
| |
| static char *scale_type = "rcu"; |
| module_param(scale_type, charp, 0444); |
| MODULE_PARM_DESC(scale_type, "Type of RCU to scalability-test (rcu, srcu, ...)"); |
| |
| static int nrealreaders; |
| static int nrealwriters; |
| static struct task_struct **writer_tasks; |
| static struct task_struct **reader_tasks; |
| static struct task_struct *shutdown_task; |
| |
| static u64 **writer_durations; |
| static int *writer_n_durations; |
| static atomic_t n_rcu_scale_reader_started; |
| static atomic_t n_rcu_scale_writer_started; |
| static atomic_t n_rcu_scale_writer_finished; |
| static wait_queue_head_t shutdown_wq; |
| static u64 t_rcu_scale_writer_started; |
| static u64 t_rcu_scale_writer_finished; |
| static unsigned long b_rcu_gp_test_started; |
| static unsigned long b_rcu_gp_test_finished; |
| static DEFINE_PER_CPU(atomic_t, n_async_inflight); |
| |
| #define MAX_MEAS 10000 |
| #define MIN_MEAS 100 |
| |
| /* |
| * Operations vector for selecting different types of tests. |
| */ |
| |
| struct rcu_scale_ops { |
| int ptype; |
| void (*init)(void); |
| void (*cleanup)(void); |
| int (*readlock)(void); |
| void (*readunlock)(int idx); |
| unsigned long (*get_gp_seq)(void); |
| unsigned long (*gp_diff)(unsigned long new, unsigned long old); |
| unsigned long (*exp_completed)(void); |
| void (*async)(struct rcu_head *head, rcu_callback_t func); |
| void (*gp_barrier)(void); |
| void (*sync)(void); |
| void (*exp_sync)(void); |
| const char *name; |
| }; |
| |
| static struct rcu_scale_ops *cur_ops; |
| |
| /* |
| * Definitions for rcu scalability testing. |
| */ |
| |
| static int rcu_scale_read_lock(void) __acquires(RCU) |
| { |
| rcu_read_lock(); |
| return 0; |
| } |
| |
| static void rcu_scale_read_unlock(int idx) __releases(RCU) |
| { |
| rcu_read_unlock(); |
| } |
| |
| static unsigned long __maybe_unused rcu_no_completed(void) |
| { |
| return 0; |
| } |
| |
| static void rcu_sync_scale_init(void) |
| { |
| } |
| |
| static struct rcu_scale_ops rcu_ops = { |
| .ptype = RCU_FLAVOR, |
| .init = rcu_sync_scale_init, |
| .readlock = rcu_scale_read_lock, |
| .readunlock = rcu_scale_read_unlock, |
| .get_gp_seq = rcu_get_gp_seq, |
| .gp_diff = rcu_seq_diff, |
| .exp_completed = rcu_exp_batches_completed, |
| .async = call_rcu, |
| .gp_barrier = rcu_barrier, |
| .sync = synchronize_rcu, |
| .exp_sync = synchronize_rcu_expedited, |
| .name = "rcu" |
| }; |
| |
| /* |
| * Definitions for srcu scalability testing. |
| */ |
| |
| DEFINE_STATIC_SRCU(srcu_ctl_scale); |
| static struct srcu_struct *srcu_ctlp = &srcu_ctl_scale; |
| |
| static int srcu_scale_read_lock(void) __acquires(srcu_ctlp) |
| { |
| return srcu_read_lock(srcu_ctlp); |
| } |
| |
| static void srcu_scale_read_unlock(int idx) __releases(srcu_ctlp) |
| { |
| srcu_read_unlock(srcu_ctlp, idx); |
| } |
| |
| static unsigned long srcu_scale_completed(void) |
| { |
| return srcu_batches_completed(srcu_ctlp); |
| } |
| |
| static void srcu_call_rcu(struct rcu_head *head, rcu_callback_t func) |
| { |
| call_srcu(srcu_ctlp, head, func); |
| } |
| |
| static void srcu_rcu_barrier(void) |
| { |
| srcu_barrier(srcu_ctlp); |
| } |
| |
| static void srcu_scale_synchronize(void) |
| { |
| synchronize_srcu(srcu_ctlp); |
| } |
| |
| static void srcu_scale_synchronize_expedited(void) |
| { |
| synchronize_srcu_expedited(srcu_ctlp); |
| } |
| |
| static struct rcu_scale_ops srcu_ops = { |
| .ptype = SRCU_FLAVOR, |
| .init = rcu_sync_scale_init, |
| .readlock = srcu_scale_read_lock, |
| .readunlock = srcu_scale_read_unlock, |
| .get_gp_seq = srcu_scale_completed, |
| .gp_diff = rcu_seq_diff, |
| .exp_completed = srcu_scale_completed, |
| .async = srcu_call_rcu, |
| .gp_barrier = srcu_rcu_barrier, |
| .sync = srcu_scale_synchronize, |
| .exp_sync = srcu_scale_synchronize_expedited, |
| .name = "srcu" |
| }; |
| |
| static struct srcu_struct srcud; |
| |
| static void srcu_sync_scale_init(void) |
| { |
| srcu_ctlp = &srcud; |
| init_srcu_struct(srcu_ctlp); |
| } |
| |
| static void srcu_sync_scale_cleanup(void) |
| { |
| cleanup_srcu_struct(srcu_ctlp); |
| } |
| |
| static struct rcu_scale_ops srcud_ops = { |
| .ptype = SRCU_FLAVOR, |
| .init = srcu_sync_scale_init, |
| .cleanup = srcu_sync_scale_cleanup, |
| .readlock = srcu_scale_read_lock, |
| .readunlock = srcu_scale_read_unlock, |
| .get_gp_seq = srcu_scale_completed, |
| .gp_diff = rcu_seq_diff, |
| .exp_completed = srcu_scale_completed, |
| .async = srcu_call_rcu, |
| .gp_barrier = srcu_rcu_barrier, |
| .sync = srcu_scale_synchronize, |
| .exp_sync = srcu_scale_synchronize_expedited, |
| .name = "srcud" |
| }; |
| |
| #ifdef CONFIG_TASKS_RCU |
| |
| /* |
| * Definitions for RCU-tasks scalability testing. |
| */ |
| |
| static int tasks_scale_read_lock(void) |
| { |
| return 0; |
| } |
| |
| static void tasks_scale_read_unlock(int idx) |
| { |
| } |
| |
| static struct rcu_scale_ops tasks_ops = { |
| .ptype = RCU_TASKS_FLAVOR, |
| .init = rcu_sync_scale_init, |
| .readlock = tasks_scale_read_lock, |
| .readunlock = tasks_scale_read_unlock, |
| .get_gp_seq = rcu_no_completed, |
| .gp_diff = rcu_seq_diff, |
| .async = call_rcu_tasks, |
| .gp_barrier = rcu_barrier_tasks, |
| .sync = synchronize_rcu_tasks, |
| .exp_sync = synchronize_rcu_tasks, |
| .name = "tasks" |
| }; |
| |
| #define TASKS_OPS &tasks_ops, |
| |
| #else // #ifdef CONFIG_TASKS_RCU |
| |
| #define TASKS_OPS |
| |
| #endif // #else // #ifdef CONFIG_TASKS_RCU |
| |
| #ifdef CONFIG_TASKS_TRACE_RCU |
| |
| /* |
| * Definitions for RCU-tasks-trace scalability testing. |
| */ |
| |
| static int tasks_trace_scale_read_lock(void) |
| { |
| rcu_read_lock_trace(); |
| return 0; |
| } |
| |
| static void tasks_trace_scale_read_unlock(int idx) |
| { |
| rcu_read_unlock_trace(); |
| } |
| |
| static struct rcu_scale_ops tasks_tracing_ops = { |
| .ptype = RCU_TASKS_FLAVOR, |
| .init = rcu_sync_scale_init, |
| .readlock = tasks_trace_scale_read_lock, |
| .readunlock = tasks_trace_scale_read_unlock, |
| .get_gp_seq = rcu_no_completed, |
| .gp_diff = rcu_seq_diff, |
| .async = call_rcu_tasks_trace, |
| .gp_barrier = rcu_barrier_tasks_trace, |
| .sync = synchronize_rcu_tasks_trace, |
| .exp_sync = synchronize_rcu_tasks_trace, |
| .name = "tasks-tracing" |
| }; |
| |
| #define TASKS_TRACING_OPS &tasks_tracing_ops, |
| |
| #else // #ifdef CONFIG_TASKS_TRACE_RCU |
| |
| #define TASKS_TRACING_OPS |
| |
| #endif // #else // #ifdef CONFIG_TASKS_TRACE_RCU |
| |
| static unsigned long rcuscale_seq_diff(unsigned long new, unsigned long old) |
| { |
| if (!cur_ops->gp_diff) |
| return new - old; |
| return cur_ops->gp_diff(new, old); |
| } |
| |
| /* |
| * If scalability tests complete, wait for shutdown to commence. |
| */ |
| static void rcu_scale_wait_shutdown(void) |
| { |
| cond_resched_tasks_rcu_qs(); |
| if (atomic_read(&n_rcu_scale_writer_finished) < nrealwriters) |
| return; |
| while (!torture_must_stop()) |
| schedule_timeout_uninterruptible(1); |
| } |
| |
| /* |
| * RCU scalability reader kthread. Repeatedly does empty RCU read-side |
| * critical section, minimizing update-side interference. However, the |
| * point of this test is not to evaluate reader scalability, but instead |
| * to serve as a test load for update-side scalability testing. |
| */ |
| static int |
| rcu_scale_reader(void *arg) |
| { |
| unsigned long flags; |
| int idx; |
| long me = (long)arg; |
| |
| VERBOSE_SCALEOUT_STRING("rcu_scale_reader task started"); |
| set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids)); |
| set_user_nice(current, MAX_NICE); |
| atomic_inc(&n_rcu_scale_reader_started); |
| |
| do { |
| local_irq_save(flags); |
| idx = cur_ops->readlock(); |
| cur_ops->readunlock(idx); |
| local_irq_restore(flags); |
| rcu_scale_wait_shutdown(); |
| } while (!torture_must_stop()); |
| torture_kthread_stopping("rcu_scale_reader"); |
| return 0; |
| } |
| |
| /* |
| * Callback function for asynchronous grace periods from rcu_scale_writer(). |
| */ |
| static void rcu_scale_async_cb(struct rcu_head *rhp) |
| { |
| atomic_dec(this_cpu_ptr(&n_async_inflight)); |
| kfree(rhp); |
| } |
| |
| /* |
| * RCU scale writer kthread. Repeatedly does a grace period. |
| */ |
| static int |
| rcu_scale_writer(void *arg) |
| { |
| int i = 0; |
| int i_max; |
| long me = (long)arg; |
| struct rcu_head *rhp = NULL; |
| bool started = false, done = false, alldone = false; |
| u64 t; |
| u64 *wdp; |
| u64 *wdpp = writer_durations[me]; |
| |
| VERBOSE_SCALEOUT_STRING("rcu_scale_writer task started"); |
| WARN_ON(!wdpp); |
| set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids)); |
| current->flags |= PF_NO_SETAFFINITY; |
| sched_set_fifo_low(current); |
| |
| if (holdoff) |
| schedule_timeout_uninterruptible(holdoff * HZ); |
| |
| /* |
| * Wait until rcu_end_inkernel_boot() is called for normal GP tests |
| * so that RCU is not always expedited for normal GP tests. |
| * The system_state test is approximate, but works well in practice. |
| */ |
| while (!gp_exp && system_state != SYSTEM_RUNNING) |
| schedule_timeout_uninterruptible(1); |
| |
| t = ktime_get_mono_fast_ns(); |
| if (atomic_inc_return(&n_rcu_scale_writer_started) >= nrealwriters) { |
| t_rcu_scale_writer_started = t; |
| if (gp_exp) { |
| b_rcu_gp_test_started = |
| cur_ops->exp_completed() / 2; |
| } else { |
| b_rcu_gp_test_started = cur_ops->get_gp_seq(); |
| } |
| } |
| |
| do { |
| if (writer_holdoff) |
| udelay(writer_holdoff); |
| wdp = &wdpp[i]; |
| *wdp = ktime_get_mono_fast_ns(); |
| if (gp_async) { |
| retry: |
| if (!rhp) |
| rhp = kmalloc(sizeof(*rhp), GFP_KERNEL); |
| if (rhp && atomic_read(this_cpu_ptr(&n_async_inflight)) < gp_async_max) { |
| atomic_inc(this_cpu_ptr(&n_async_inflight)); |
| cur_ops->async(rhp, rcu_scale_async_cb); |
| rhp = NULL; |
| } else if (!kthread_should_stop()) { |
| cur_ops->gp_barrier(); |
| goto retry; |
| } else { |
| kfree(rhp); /* Because we are stopping. */ |
| } |
| } else if (gp_exp) { |
| cur_ops->exp_sync(); |
| } else { |
| cur_ops->sync(); |
| } |
| t = ktime_get_mono_fast_ns(); |
| *wdp = t - *wdp; |
| i_max = i; |
| if (!started && |
| atomic_read(&n_rcu_scale_writer_started) >= nrealwriters) |
| started = true; |
| if (!done && i >= MIN_MEAS) { |
| done = true; |
| sched_set_normal(current, 0); |
| pr_alert("%s%s rcu_scale_writer %ld has %d measurements\n", |
| scale_type, SCALE_FLAG, me, MIN_MEAS); |
| if (atomic_inc_return(&n_rcu_scale_writer_finished) >= |
| nrealwriters) { |
| schedule_timeout_interruptible(10); |
| rcu_ftrace_dump(DUMP_ALL); |
| SCALEOUT_STRING("Test complete"); |
| t_rcu_scale_writer_finished = t; |
| if (gp_exp) { |
| b_rcu_gp_test_finished = |
| cur_ops->exp_completed() / 2; |
| } else { |
| b_rcu_gp_test_finished = |
| cur_ops->get_gp_seq(); |
| } |
| if (shutdown) { |
| smp_mb(); /* Assign before wake. */ |
| wake_up(&shutdown_wq); |
| } |
| } |
| } |
| if (done && !alldone && |
| atomic_read(&n_rcu_scale_writer_finished) >= nrealwriters) |
| alldone = true; |
| if (started && !alldone && i < MAX_MEAS - 1) |
| i++; |
| rcu_scale_wait_shutdown(); |
| } while (!torture_must_stop()); |
| if (gp_async) { |
| cur_ops->gp_barrier(); |
| } |
| writer_n_durations[me] = i_max + 1; |
| torture_kthread_stopping("rcu_scale_writer"); |
| return 0; |
| } |
| |
| static void |
| rcu_scale_print_module_parms(struct rcu_scale_ops *cur_ops, const char *tag) |
| { |
| pr_alert("%s" SCALE_FLAG |
| "--- %s: nreaders=%d nwriters=%d verbose=%d shutdown=%d\n", |
| scale_type, tag, nrealreaders, nrealwriters, verbose, shutdown); |
| } |
| |
| static void |
| rcu_scale_cleanup(void) |
| { |
| int i; |
| int j; |
| int ngps = 0; |
| u64 *wdp; |
| u64 *wdpp; |
| |
| /* |
| * Would like warning at start, but everything is expedited |
| * during the mid-boot phase, so have to wait till the end. |
| */ |
| if (rcu_gp_is_expedited() && !rcu_gp_is_normal() && !gp_exp) |
| SCALEOUT_ERRSTRING("All grace periods expedited, no normal ones to measure!"); |
| if (rcu_gp_is_normal() && gp_exp) |
| SCALEOUT_ERRSTRING("All grace periods normal, no expedited ones to measure!"); |
| if (gp_exp && gp_async) |
| SCALEOUT_ERRSTRING("No expedited async GPs, so went with async!"); |
| |
| if (torture_cleanup_begin()) |
| return; |
| if (!cur_ops) { |
| torture_cleanup_end(); |
| return; |
| } |
| |
| if (reader_tasks) { |
| for (i = 0; i < nrealreaders; i++) |
| torture_stop_kthread(rcu_scale_reader, |
| reader_tasks[i]); |
| kfree(reader_tasks); |
| } |
| |
| if (writer_tasks) { |
| for (i = 0; i < nrealwriters; i++) { |
| torture_stop_kthread(rcu_scale_writer, |
| writer_tasks[i]); |
| if (!writer_n_durations) |
| continue; |
| j = writer_n_durations[i]; |
| pr_alert("%s%s writer %d gps: %d\n", |
| scale_type, SCALE_FLAG, i, j); |
| ngps += j; |
| } |
| pr_alert("%s%s start: %llu end: %llu duration: %llu gps: %d batches: %ld\n", |
| scale_type, SCALE_FLAG, |
| t_rcu_scale_writer_started, t_rcu_scale_writer_finished, |
| t_rcu_scale_writer_finished - |
| t_rcu_scale_writer_started, |
| ngps, |
| rcuscale_seq_diff(b_rcu_gp_test_finished, |
| b_rcu_gp_test_started)); |
| for (i = 0; i < nrealwriters; i++) { |
| if (!writer_durations) |
| break; |
| if (!writer_n_durations) |
| continue; |
| wdpp = writer_durations[i]; |
| if (!wdpp) |
| continue; |
| for (j = 0; j < writer_n_durations[i]; j++) { |
| wdp = &wdpp[j]; |
| pr_alert("%s%s %4d writer-duration: %5d %llu\n", |
| scale_type, SCALE_FLAG, |
| i, j, *wdp); |
| if (j % 100 == 0) |
| schedule_timeout_uninterruptible(1); |
| } |
| kfree(writer_durations[i]); |
| } |
| kfree(writer_tasks); |
| kfree(writer_durations); |
| kfree(writer_n_durations); |
| } |
| |
| /* Do torture-type-specific cleanup operations. */ |
| if (cur_ops->cleanup != NULL) |
| cur_ops->cleanup(); |
| |
| torture_cleanup_end(); |
| } |
| |
| /* |
| * Return the number if non-negative. If -1, the number of CPUs. |
| * If less than -1, that much less than the number of CPUs, but |
| * at least one. |
| */ |
| static int compute_real(int n) |
| { |
| int nr; |
| |
| if (n >= 0) { |
| nr = n; |
| } else { |
| nr = num_online_cpus() + 1 + n; |
| if (nr <= 0) |
| nr = 1; |
| } |
| return nr; |
| } |
| |
| /* |
| * RCU scalability shutdown kthread. Just waits to be awakened, then shuts |
| * down system. |
| */ |
| static int |
| rcu_scale_shutdown(void *arg) |
| { |
| wait_event(shutdown_wq, |
| atomic_read(&n_rcu_scale_writer_finished) >= nrealwriters); |
| smp_mb(); /* Wake before output. */ |
| rcu_scale_cleanup(); |
| kernel_power_off(); |
| return -EINVAL; |
| } |
| |
| /* |
| * kfree_rcu() scalability tests: Start a kfree_rcu() loop on all CPUs for number |
| * of iterations and measure total time and number of GP for all iterations to complete. |
| */ |
| |
| torture_param(int, kfree_nthreads, -1, "Number of threads running loops of kfree_rcu()."); |
| torture_param(int, kfree_alloc_num, 8000, "Number of allocations and frees done in an iteration."); |
| torture_param(int, kfree_loops, 10, "Number of loops doing kfree_alloc_num allocations and frees."); |
| torture_param(bool, kfree_rcu_test_double, false, "Do we run a kfree_rcu() double-argument scale test?"); |
| torture_param(bool, kfree_rcu_test_single, false, "Do we run a kfree_rcu() single-argument scale test?"); |
| |
| static struct task_struct **kfree_reader_tasks; |
| static int kfree_nrealthreads; |
| static atomic_t n_kfree_scale_thread_started; |
| static atomic_t n_kfree_scale_thread_ended; |
| |
| struct kfree_obj { |
| char kfree_obj[8]; |
| struct rcu_head rh; |
| }; |
| |
| static int |
| kfree_scale_thread(void *arg) |
| { |
| int i, loop = 0; |
| long me = (long)arg; |
| struct kfree_obj *alloc_ptr; |
| u64 start_time, end_time; |
| long long mem_begin, mem_during = 0; |
| bool kfree_rcu_test_both; |
| DEFINE_TORTURE_RANDOM(tr); |
| |
| VERBOSE_SCALEOUT_STRING("kfree_scale_thread task started"); |
| set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids)); |
| set_user_nice(current, MAX_NICE); |
| kfree_rcu_test_both = (kfree_rcu_test_single == kfree_rcu_test_double); |
| |
| start_time = ktime_get_mono_fast_ns(); |
| |
| if (atomic_inc_return(&n_kfree_scale_thread_started) >= kfree_nrealthreads) { |
| if (gp_exp) |
| b_rcu_gp_test_started = cur_ops->exp_completed() / 2; |
| else |
| b_rcu_gp_test_started = cur_ops->get_gp_seq(); |
| } |
| |
| do { |
| if (!mem_during) { |
| mem_during = mem_begin = si_mem_available(); |
| } else if (loop % (kfree_loops / 4) == 0) { |
| mem_during = (mem_during + si_mem_available()) / 2; |
| } |
| |
| for (i = 0; i < kfree_alloc_num; i++) { |
| alloc_ptr = kmalloc(kfree_mult * sizeof(struct kfree_obj), GFP_KERNEL); |
| if (!alloc_ptr) |
| return -ENOMEM; |
| |
| // By default kfree_rcu_test_single and kfree_rcu_test_double are |
| // initialized to false. If both have the same value (false or true) |
| // both are randomly tested, otherwise only the one with value true |
| // is tested. |
| if ((kfree_rcu_test_single && !kfree_rcu_test_double) || |
| (kfree_rcu_test_both && torture_random(&tr) & 0x800)) |
| kfree_rcu(alloc_ptr); |
| else |
| kfree_rcu(alloc_ptr, rh); |
| } |
| |
| cond_resched(); |
| } while (!torture_must_stop() && ++loop < kfree_loops); |
| |
| if (atomic_inc_return(&n_kfree_scale_thread_ended) >= kfree_nrealthreads) { |
| end_time = ktime_get_mono_fast_ns(); |
| |
| if (gp_exp) |
| b_rcu_gp_test_finished = cur_ops->exp_completed() / 2; |
| else |
| b_rcu_gp_test_finished = cur_ops->get_gp_seq(); |
| |
| pr_alert("Total time taken by all kfree'ers: %llu ns, loops: %d, batches: %ld, memory footprint: %lldMB\n", |
| (unsigned long long)(end_time - start_time), kfree_loops, |
| rcuscale_seq_diff(b_rcu_gp_test_finished, b_rcu_gp_test_started), |
| (mem_begin - mem_during) >> (20 - PAGE_SHIFT)); |
| |
| if (shutdown) { |
| smp_mb(); /* Assign before wake. */ |
| wake_up(&shutdown_wq); |
| } |
| } |
| |
| torture_kthread_stopping("kfree_scale_thread"); |
| return 0; |
| } |
| |
| static void |
| kfree_scale_cleanup(void) |
| { |
| int i; |
| |
| if (torture_cleanup_begin()) |
| return; |
| |
| if (kfree_reader_tasks) { |
| for (i = 0; i < kfree_nrealthreads; i++) |
| torture_stop_kthread(kfree_scale_thread, |
| kfree_reader_tasks[i]); |
| kfree(kfree_reader_tasks); |
| } |
| |
| torture_cleanup_end(); |
| } |
| |
| /* |
| * shutdown kthread. Just waits to be awakened, then shuts down system. |
| */ |
| static int |
| kfree_scale_shutdown(void *arg) |
| { |
| wait_event(shutdown_wq, |
| atomic_read(&n_kfree_scale_thread_ended) >= kfree_nrealthreads); |
| |
| smp_mb(); /* Wake before output. */ |
| |
| kfree_scale_cleanup(); |
| kernel_power_off(); |
| return -EINVAL; |
| } |
| |
| static int __init |
| kfree_scale_init(void) |
| { |
| long i; |
| int firsterr = 0; |
| |
| kfree_nrealthreads = compute_real(kfree_nthreads); |
| /* Start up the kthreads. */ |
| if (shutdown) { |
| init_waitqueue_head(&shutdown_wq); |
| firsterr = torture_create_kthread(kfree_scale_shutdown, NULL, |
| shutdown_task); |
| if (torture_init_error(firsterr)) |
| goto unwind; |
| schedule_timeout_uninterruptible(1); |
| } |
| |
| pr_alert("kfree object size=%zu\n", kfree_mult * sizeof(struct kfree_obj)); |
| |
| kfree_reader_tasks = kcalloc(kfree_nrealthreads, sizeof(kfree_reader_tasks[0]), |
| GFP_KERNEL); |
| if (kfree_reader_tasks == NULL) { |
| firsterr = -ENOMEM; |
| goto unwind; |
| } |
| |
| for (i = 0; i < kfree_nrealthreads; i++) { |
| firsterr = torture_create_kthread(kfree_scale_thread, (void *)i, |
| kfree_reader_tasks[i]); |
| if (torture_init_error(firsterr)) |
| goto unwind; |
| } |
| |
| while (atomic_read(&n_kfree_scale_thread_started) < kfree_nrealthreads) |
| schedule_timeout_uninterruptible(1); |
| |
| torture_init_end(); |
| return 0; |
| |
| unwind: |
| torture_init_end(); |
| kfree_scale_cleanup(); |
| return firsterr; |
| } |
| |
| static int __init |
| rcu_scale_init(void) |
| { |
| long i; |
| int firsterr = 0; |
| static struct rcu_scale_ops *scale_ops[] = { |
| &rcu_ops, &srcu_ops, &srcud_ops, TASKS_OPS TASKS_TRACING_OPS |
| }; |
| |
| if (!torture_init_begin(scale_type, verbose)) |
| return -EBUSY; |
| |
| /* Process args and announce that the scalability'er is on the job. */ |
| for (i = 0; i < ARRAY_SIZE(scale_ops); i++) { |
| cur_ops = scale_ops[i]; |
| if (strcmp(scale_type, cur_ops->name) == 0) |
| break; |
| } |
| if (i == ARRAY_SIZE(scale_ops)) { |
| pr_alert("rcu-scale: invalid scale type: \"%s\"\n", scale_type); |
| pr_alert("rcu-scale types:"); |
| for (i = 0; i < ARRAY_SIZE(scale_ops); i++) |
| pr_cont(" %s", scale_ops[i]->name); |
| pr_cont("\n"); |
| firsterr = -EINVAL; |
| cur_ops = NULL; |
| goto unwind; |
| } |
| if (cur_ops->init) |
| cur_ops->init(); |
| |
| if (kfree_rcu_test) |
| return kfree_scale_init(); |
| |
| nrealwriters = compute_real(nwriters); |
| nrealreaders = compute_real(nreaders); |
| atomic_set(&n_rcu_scale_reader_started, 0); |
| atomic_set(&n_rcu_scale_writer_started, 0); |
| atomic_set(&n_rcu_scale_writer_finished, 0); |
| rcu_scale_print_module_parms(cur_ops, "Start of test"); |
| |
| /* Start up the kthreads. */ |
| |
| if (shutdown) { |
| init_waitqueue_head(&shutdown_wq); |
| firsterr = torture_create_kthread(rcu_scale_shutdown, NULL, |
| shutdown_task); |
| if (torture_init_error(firsterr)) |
| goto unwind; |
| schedule_timeout_uninterruptible(1); |
| } |
| reader_tasks = kcalloc(nrealreaders, sizeof(reader_tasks[0]), |
| GFP_KERNEL); |
| if (reader_tasks == NULL) { |
| SCALEOUT_ERRSTRING("out of memory"); |
| firsterr = -ENOMEM; |
| goto unwind; |
| } |
| for (i = 0; i < nrealreaders; i++) { |
| firsterr = torture_create_kthread(rcu_scale_reader, (void *)i, |
| reader_tasks[i]); |
| if (torture_init_error(firsterr)) |
| goto unwind; |
| } |
| while (atomic_read(&n_rcu_scale_reader_started) < nrealreaders) |
| schedule_timeout_uninterruptible(1); |
| writer_tasks = kcalloc(nrealwriters, sizeof(reader_tasks[0]), |
| GFP_KERNEL); |
| writer_durations = kcalloc(nrealwriters, sizeof(*writer_durations), |
| GFP_KERNEL); |
| writer_n_durations = |
| kcalloc(nrealwriters, sizeof(*writer_n_durations), |
| GFP_KERNEL); |
| if (!writer_tasks || !writer_durations || !writer_n_durations) { |
| SCALEOUT_ERRSTRING("out of memory"); |
| firsterr = -ENOMEM; |
| goto unwind; |
| } |
| for (i = 0; i < nrealwriters; i++) { |
| writer_durations[i] = |
| kcalloc(MAX_MEAS, sizeof(*writer_durations[i]), |
| GFP_KERNEL); |
| if (!writer_durations[i]) { |
| firsterr = -ENOMEM; |
| goto unwind; |
| } |
| firsterr = torture_create_kthread(rcu_scale_writer, (void *)i, |
| writer_tasks[i]); |
| if (torture_init_error(firsterr)) |
| goto unwind; |
| } |
| torture_init_end(); |
| return 0; |
| |
| unwind: |
| torture_init_end(); |
| rcu_scale_cleanup(); |
| if (shutdown) { |
| WARN_ON(!IS_MODULE(CONFIG_RCU_SCALE_TEST)); |
| kernel_power_off(); |
| } |
| return firsterr; |
| } |
| |
| module_init(rcu_scale_init); |
| module_exit(rcu_scale_cleanup); |