diff options
Diffstat (limited to 'kernel/rcu/refscale.c')
| -rw-r--r-- | kernel/rcu/refscale.c | 471 |
1 files changed, 404 insertions, 67 deletions
diff --git a/kernel/rcu/refscale.c b/kernel/rcu/refscale.c index 1b47376acdc4..a2d9d75d88a1 100644 --- a/kernel/rcu/refscale.c +++ b/kernel/rcu/refscale.c @@ -85,22 +85,16 @@ torture_param(int, holdoff, IS_BUILTIN(CONFIG_RCU_REF_SCALE_TEST) ? 10 : 0, // Number of typesafe_lookup structures, that is, the degree of concurrency. torture_param(long, lookup_instances, 0, "Number of typesafe_lookup structures."); // Number of loops per experiment, all readers execute operations concurrently. -torture_param(long, loops, 10000, "Number of loops per experiment."); +torture_param(int, loops, 10000, "Number of loops per experiment."); // Number of readers, with -1 defaulting to about 75% of the CPUs. torture_param(int, nreaders, -1, "Number of readers, -1 for 75% of CPUs."); // Number of runs. torture_param(int, nruns, 30, "Number of experiments to run."); // Reader delay in nanoseconds, 0 for no delay. torture_param(int, readdelay, 0, "Read-side delay in nanoseconds."); - -#ifdef MODULE -# define REFSCALE_SHUTDOWN 0 -#else -# define REFSCALE_SHUTDOWN 1 -#endif - -torture_param(bool, shutdown, REFSCALE_SHUTDOWN, - "Shutdown at end of scalability tests."); +// Maximum shutdown delay in seconds, or zero for no shutdown. +torture_param(int, shutdown_secs, !IS_MODULE(CONFIG_REPRO_TEST) * 300, + "Shutdown at end of scalability tests or at specified timeout (s)."); struct reader_task { struct task_struct *task; @@ -109,12 +103,8 @@ struct reader_task { u64 last_duration_ns; }; -static struct task_struct *shutdown_task; -static wait_queue_head_t shutdown_wq; - static struct task_struct *main_task; static wait_queue_head_t main_wq; -static int shutdown_start; static struct reader_task *reader_tasks; @@ -136,6 +126,7 @@ struct ref_scale_ops { void (*cleanup)(void); void (*readsection)(const int nloops); void (*delaysection)(const int nloops, const int udl, const int ndl); + bool enable_irqs; const char *name; }; @@ -184,6 +175,8 @@ static const struct ref_scale_ops rcu_ops = { // Definitions for SRCU ref scale testing. DEFINE_STATIC_SRCU(srcu_refctl_scale); +DEFINE_STATIC_SRCU_FAST(srcu_fast_refctl_scale); +DEFINE_STATIC_SRCU_FAST_UPDOWN(srcu_fast_updown_refctl_scale); static struct srcu_struct *srcu_ctlp = &srcu_refctl_scale; static void srcu_ref_scale_read_section(const int nloops) @@ -216,34 +209,76 @@ static const struct ref_scale_ops srcu_ops = { .name = "srcu" }; -static void srcu_lite_ref_scale_read_section(const int nloops) +static bool srcu_fast_sync_scale_init(void) +{ + srcu_ctlp = &srcu_fast_refctl_scale; + return true; +} + +static void srcu_fast_ref_scale_read_section(const int nloops) { int i; - int idx; + struct srcu_ctr __percpu *scp; for (i = nloops; i >= 0; i--) { - idx = srcu_read_lock_lite(srcu_ctlp); - srcu_read_unlock_lite(srcu_ctlp, idx); + scp = srcu_read_lock_fast(srcu_ctlp); + srcu_read_unlock_fast(srcu_ctlp, scp); } } -static void srcu_lite_ref_scale_delay_section(const int nloops, const int udl, const int ndl) +static void srcu_fast_ref_scale_delay_section(const int nloops, const int udl, const int ndl) { int i; - int idx; + struct srcu_ctr __percpu *scp; for (i = nloops; i >= 0; i--) { - idx = srcu_read_lock_lite(srcu_ctlp); + scp = srcu_read_lock_fast(srcu_ctlp); un_delay(udl, ndl); - srcu_read_unlock_lite(srcu_ctlp, idx); + srcu_read_unlock_fast(srcu_ctlp, scp); } } -static const struct ref_scale_ops srcu_lite_ops = { - .init = rcu_sync_scale_init, - .readsection = srcu_lite_ref_scale_read_section, - .delaysection = srcu_lite_ref_scale_delay_section, - .name = "srcu-lite" +static const struct ref_scale_ops srcu_fast_ops = { + .init = srcu_fast_sync_scale_init, + .readsection = srcu_fast_ref_scale_read_section, + .delaysection = srcu_fast_ref_scale_delay_section, + .name = "srcu-fast" +}; + +static bool srcu_fast_updown_sync_scale_init(void) +{ + srcu_ctlp = &srcu_fast_updown_refctl_scale; + return true; +} + +static void srcu_fast_updown_ref_scale_read_section(const int nloops) +{ + int i; + struct srcu_ctr __percpu *scp; + + for (i = nloops; i >= 0; i--) { + scp = srcu_read_lock_fast_updown(srcu_ctlp); + srcu_read_unlock_fast_updown(srcu_ctlp, scp); + } +} + +static void srcu_fast_updown_ref_scale_delay_section(const int nloops, const int udl, const int ndl) +{ + int i; + struct srcu_ctr __percpu *scp; + + for (i = nloops; i >= 0; i--) { + scp = srcu_read_lock_fast_updown(srcu_ctlp); + un_delay(udl, ndl); + srcu_read_unlock_fast_updown(srcu_ctlp, scp); + } +} + +static const struct ref_scale_ops srcu_fast_updown_ops = { + .init = srcu_fast_updown_sync_scale_init, + .readsection = srcu_fast_updown_ref_scale_read_section, + .delaysection = srcu_fast_updown_ref_scale_delay_section, + .name = "srcu-fast-updown" }; #ifdef CONFIG_TASKS_RCU @@ -323,6 +358,9 @@ static const struct ref_scale_ops rcu_trace_ops = { // Definitions for reference count static atomic_t refcnt; +// Definitions acquire-release. +static DEFINE_PER_CPU(unsigned long, test_acqrel); + static void ref_refcnt_section(const int nloops) { int i; @@ -351,6 +389,184 @@ static const struct ref_scale_ops refcnt_ops = { .name = "refcnt" }; +static void ref_percpuinc_section(const int nloops) +{ + int i; + + for (i = nloops; i >= 0; i--) { + this_cpu_inc(test_acqrel); + this_cpu_dec(test_acqrel); + } +} + +static void ref_percpuinc_delay_section(const int nloops, const int udl, const int ndl) +{ + int i; + + for (i = nloops; i >= 0; i--) { + this_cpu_inc(test_acqrel); + un_delay(udl, ndl); + this_cpu_dec(test_acqrel); + } +} + +static const struct ref_scale_ops percpuinc_ops = { + .init = rcu_sync_scale_init, + .readsection = ref_percpuinc_section, + .delaysection = ref_percpuinc_delay_section, + .name = "percpuinc" +}; + +// Note that this can lose counts in preemptible kernels. +static void ref_incpercpu_section(const int nloops) +{ + int i; + + for (i = nloops; i >= 0; i--) { + unsigned long *tap = this_cpu_ptr(&test_acqrel); + + WRITE_ONCE(*tap, READ_ONCE(*tap) + 1); + WRITE_ONCE(*tap, READ_ONCE(*tap) - 1); + } +} + +static void ref_incpercpu_delay_section(const int nloops, const int udl, const int ndl) +{ + int i; + + for (i = nloops; i >= 0; i--) { + unsigned long *tap = this_cpu_ptr(&test_acqrel); + + WRITE_ONCE(*tap, READ_ONCE(*tap) + 1); + un_delay(udl, ndl); + WRITE_ONCE(*tap, READ_ONCE(*tap) - 1); + } +} + +static const struct ref_scale_ops incpercpu_ops = { + .init = rcu_sync_scale_init, + .readsection = ref_incpercpu_section, + .delaysection = ref_incpercpu_delay_section, + .name = "incpercpu" +}; + +static void ref_incpercpupreempt_section(const int nloops) +{ + int i; + + for (i = nloops; i >= 0; i--) { + unsigned long *tap; + + preempt_disable(); + tap = this_cpu_ptr(&test_acqrel); + WRITE_ONCE(*tap, READ_ONCE(*tap) + 1); + WRITE_ONCE(*tap, READ_ONCE(*tap) - 1); + preempt_enable(); + } +} + +static void ref_incpercpupreempt_delay_section(const int nloops, const int udl, const int ndl) +{ + int i; + + for (i = nloops; i >= 0; i--) { + unsigned long *tap; + + preempt_disable(); + tap = this_cpu_ptr(&test_acqrel); + WRITE_ONCE(*tap, READ_ONCE(*tap) + 1); + un_delay(udl, ndl); + WRITE_ONCE(*tap, READ_ONCE(*tap) - 1); + preempt_enable(); + } +} + +static const struct ref_scale_ops incpercpupreempt_ops = { + .init = rcu_sync_scale_init, + .readsection = ref_incpercpupreempt_section, + .delaysection = ref_incpercpupreempt_delay_section, + .name = "incpercpupreempt" +}; + +static void ref_incpercpubh_section(const int nloops) +{ + int i; + + for (i = nloops; i >= 0; i--) { + unsigned long *tap; + + local_bh_disable(); + tap = this_cpu_ptr(&test_acqrel); + WRITE_ONCE(*tap, READ_ONCE(*tap) + 1); + WRITE_ONCE(*tap, READ_ONCE(*tap) - 1); + local_bh_enable(); + } +} + +static void ref_incpercpubh_delay_section(const int nloops, const int udl, const int ndl) +{ + int i; + + for (i = nloops; i >= 0; i--) { + unsigned long *tap; + + local_bh_disable(); + tap = this_cpu_ptr(&test_acqrel); + WRITE_ONCE(*tap, READ_ONCE(*tap) + 1); + un_delay(udl, ndl); + WRITE_ONCE(*tap, READ_ONCE(*tap) - 1); + local_bh_enable(); + } +} + +static const struct ref_scale_ops incpercpubh_ops = { + .init = rcu_sync_scale_init, + .readsection = ref_incpercpubh_section, + .delaysection = ref_incpercpubh_delay_section, + .enable_irqs = true, + .name = "incpercpubh" +}; + +static void ref_incpercpuirqsave_section(const int nloops) +{ + int i; + unsigned long flags; + + for (i = nloops; i >= 0; i--) { + unsigned long *tap; + + local_irq_save(flags); + tap = this_cpu_ptr(&test_acqrel); + WRITE_ONCE(*tap, READ_ONCE(*tap) + 1); + WRITE_ONCE(*tap, READ_ONCE(*tap) - 1); + local_irq_restore(flags); + } +} + +static void ref_incpercpuirqsave_delay_section(const int nloops, const int udl, const int ndl) +{ + int i; + unsigned long flags; + + for (i = nloops; i >= 0; i--) { + unsigned long *tap; + + local_irq_save(flags); + tap = this_cpu_ptr(&test_acqrel); + WRITE_ONCE(*tap, READ_ONCE(*tap) + 1); + un_delay(udl, ndl); + WRITE_ONCE(*tap, READ_ONCE(*tap) - 1); + local_irq_restore(flags); + } +} + +static const struct ref_scale_ops incpercpuirqsave_ops = { + .init = rcu_sync_scale_init, + .readsection = ref_incpercpuirqsave_section, + .delaysection = ref_incpercpuirqsave_delay_section, + .name = "incpercpuirqsave" +}; + // Definitions for rwlock static rwlock_t test_rwlock; @@ -494,9 +710,6 @@ static const struct ref_scale_ops lock_irq_ops = { .name = "lock-irq" }; -// Definitions acquire-release. -static DEFINE_PER_CPU(unsigned long, test_acqrel); - static void ref_acqrel_section(const int nloops) { unsigned long x; @@ -629,6 +842,133 @@ static const struct ref_scale_ops jiffies_ops = { .name = "jiffies" }; +static void ref_preempt_section(const int nloops) +{ + int i; + + migrate_disable(); + for (i = nloops; i >= 0; i--) { + preempt_disable(); + preempt_enable(); + } + migrate_enable(); +} + +static void ref_preempt_delay_section(const int nloops, const int udl, const int ndl) +{ + int i; + + migrate_disable(); + for (i = nloops; i >= 0; i--) { + preempt_disable(); + un_delay(udl, ndl); + preempt_enable(); + } + migrate_enable(); +} + +static const struct ref_scale_ops preempt_ops = { + .readsection = ref_preempt_section, + .delaysection = ref_preempt_delay_section, + .name = "preempt" +}; + +static void ref_bh_section(const int nloops) +{ + int i; + + preempt_disable(); + for (i = nloops; i >= 0; i--) { + local_bh_disable(); + local_bh_enable(); + } + preempt_enable(); +} + +static void ref_bh_delay_section(const int nloops, const int udl, const int ndl) +{ + int i; + + preempt_disable(); + for (i = nloops; i >= 0; i--) { + local_bh_disable(); + un_delay(udl, ndl); + local_bh_enable(); + } + preempt_enable(); +} + +static const struct ref_scale_ops bh_ops = { + .readsection = ref_bh_section, + .delaysection = ref_bh_delay_section, + .enable_irqs = true, + .name = "bh" +}; + +static void ref_irq_section(const int nloops) +{ + int i; + + preempt_disable(); + for (i = nloops; i >= 0; i--) { + local_irq_disable(); + local_irq_enable(); + } + preempt_enable(); +} + +static void ref_irq_delay_section(const int nloops, const int udl, const int ndl) +{ + int i; + + preempt_disable(); + for (i = nloops; i >= 0; i--) { + local_irq_disable(); + un_delay(udl, ndl); + local_irq_enable(); + } + preempt_enable(); +} + +static const struct ref_scale_ops irq_ops = { + .readsection = ref_irq_section, + .delaysection = ref_irq_delay_section, + .name = "irq" +}; + +static void ref_irqsave_section(const int nloops) +{ + unsigned long flags; + int i; + + preempt_disable(); + for (i = nloops; i >= 0; i--) { + local_irq_save(flags); + local_irq_restore(flags); + } + preempt_enable(); +} + +static void ref_irqsave_delay_section(const int nloops, const int udl, const int ndl) +{ + unsigned long flags; + int i; + + preempt_disable(); + for (i = nloops; i >= 0; i--) { + local_irq_save(flags); + un_delay(udl, ndl); + local_irq_restore(flags); + } + preempt_enable(); +} + +static const struct ref_scale_ops irqsave_ops = { + .readsection = ref_irqsave_section, + .delaysection = ref_irqsave_delay_section, + .name = "irqsave" +}; + //////////////////////////////////////////////////////////////////////// // // Methods leveraging SLAB_TYPESAFE_BY_RCU. @@ -793,7 +1133,7 @@ static bool typesafe_init(void) else if (si == 0) si = nr_cpu_ids; rtsarray_size = si; - rtsarray = kcalloc(si, sizeof(*rtsarray), GFP_KERNEL); + rtsarray = kzalloc_objs(*rtsarray, si); if (!rtsarray) return false; for (idx = 0; idx < rtsarray_size; idx++) { @@ -924,15 +1264,18 @@ repeat: if (!atomic_dec_return(&n_warmedup)) while (atomic_read_acquire(&n_warmedup)) rcu_scale_one_reader(); - // Also keep interrupts disabled. This also has the effect - // of preventing entries into slow path for rcu_read_unlock(). - local_irq_save(flags); + // Also keep interrupts disabled when it is safe to do so, which + // it is not for local_bh_enable(). This also has the effect of + // preventing entries into slow path for rcu_read_unlock(). + if (!cur_ops->enable_irqs) + local_irq_save(flags); start = ktime_get_mono_fast_ns(); rcu_scale_one_reader(); duration = ktime_get_mono_fast_ns() - start; - local_irq_restore(flags); + if (!cur_ops->enable_irqs) + local_irq_restore(flags); rt->last_duration_ns = WARN_ON_ONCE(duration < 0) ? 0 : duration; // To reduce runtime-skew noise, do maintain-load invocations until @@ -1004,6 +1347,8 @@ static u64 process_durations(int n) return sum; } +static void ref_scale_cleanup(void); + // The main_func is the main orchestrator, it performs a bunch of // experiments. For every experiment, it orders all the readers // involved to start and waits for them to finish the experiment. It @@ -1021,7 +1366,7 @@ static int main_func(void *arg) set_user_nice(current, MAX_NICE); VERBOSE_SCALEOUT("main_func task started"); - result_avg = kzalloc(nruns * sizeof(*result_avg), GFP_KERNEL); + result_avg = kcalloc(nruns, sizeof(*result_avg), GFP_KERNEL); buf = kzalloc(800 + 64, GFP_KERNEL); if (!result_avg || !buf) { SCALEOUT_ERRSTRING("out of memory"); @@ -1090,9 +1435,10 @@ static int main_func(void *arg) oom_exit: // This will shutdown everything including us. - if (shutdown) { - shutdown_start = 1; - wake_up(&shutdown_wq); + if (shutdown_secs) { + main_task = NULL; // Avoid self-kill deadlock. + ref_scale_cleanup(); + kernel_power_off(); } // Wait for torture to stop us @@ -1110,8 +1456,8 @@ static void ref_scale_print_module_parms(const struct ref_scale_ops *cur_ops, const char *tag) { pr_alert("%s" SCALE_FLAG - "--- %s: verbose=%d verbose_batched=%d shutdown=%d holdoff=%d lookup_instances=%ld loops=%ld nreaders=%d nruns=%d readdelay=%d\n", scale_type, tag, - verbose, verbose_batched, shutdown, holdoff, lookup_instances, loops, nreaders, nruns, readdelay); + "--- %s: verbose=%d verbose_batched=%d shutdown_secs=%d holdoff=%d lookup_instances=%ld loops=%d nreaders=%d nruns=%d readdelay=%d\n", scale_type, tag, + verbose, verbose_batched, shutdown_secs, holdoff, lookup_instances, loops, nreaders, nruns, readdelay); } static void @@ -1133,9 +1479,9 @@ ref_scale_cleanup(void) reader_tasks[i].task); } kfree(reader_tasks); + reader_tasks = NULL; torture_stop_kthread("main_task", main_task); - kfree(main_task); // Do scale-type-specific cleanup operations. if (cur_ops->cleanup != NULL) @@ -1144,28 +1490,19 @@ ref_scale_cleanup(void) torture_cleanup_end(); } -// Shutdown kthread. Just waits to be awakened, then shuts down system. -static int -ref_scale_shutdown(void *arg) -{ - wait_event_idle(shutdown_wq, shutdown_start); - - smp_mb(); // Wake before output. - ref_scale_cleanup(); - kernel_power_off(); - - return -EINVAL; -} - static int __init ref_scale_init(void) { long i; int firsterr = 0; static const struct ref_scale_ops *scale_ops[] = { - &rcu_ops, &srcu_ops, &srcu_lite_ops, RCU_TRACE_OPS RCU_TASKS_OPS - &refcnt_ops, &rwlock_ops, &rwsem_ops, &lock_ops, &lock_irq_ops, - &acqrel_ops, &sched_clock_ops, &clock_ops, &jiffies_ops, + &rcu_ops, &srcu_ops, &srcu_fast_ops, &srcu_fast_updown_ops, + RCU_TRACE_OPS RCU_TASKS_OPS + &refcnt_ops, &percpuinc_ops, &incpercpu_ops, &incpercpupreempt_ops, + &incpercpubh_ops, &incpercpuirqsave_ops, + &rwlock_ops, &rwsem_ops, &lock_ops, &lock_irq_ops, &acqrel_ops, + &sched_clock_ops, &clock_ops, &jiffies_ops, + &preempt_ops, &bh_ops, &irq_ops, &irqsave_ops, &typesafe_ref_ops, &typesafe_lock_ops, &typesafe_seqlock_ops, }; @@ -1196,26 +1533,26 @@ ref_scale_init(void) ref_scale_print_module_parms(cur_ops, "Start of test"); // Shutdown task - if (shutdown) { - init_waitqueue_head(&shutdown_wq); - firsterr = torture_create_kthread(ref_scale_shutdown, NULL, - shutdown_task); + if (shutdown_secs) { + firsterr = torture_shutdown_init(shutdown_secs, ref_scale_cleanup); if (torture_init_error(firsterr)) goto unwind; - schedule_timeout_uninterruptible(1); } // Reader tasks (default to ~75% of online CPUs). if (nreaders < 0) nreaders = (num_online_cpus() >> 1) + (num_online_cpus() >> 2); - if (WARN_ONCE(loops <= 0, "%s: loops = %ld, adjusted to 1\n", __func__, loops)) + if (WARN_ONCE(loops <= 0, "%s: loops = %d, adjusted to 1\n", __func__, loops)) loops = 1; if (WARN_ONCE(nreaders <= 0, "%s: nreaders = %d, adjusted to 1\n", __func__, nreaders)) nreaders = 1; if (WARN_ONCE(nruns <= 0, "%s: nruns = %d, adjusted to 1\n", __func__, nruns)) nruns = 1; - reader_tasks = kcalloc(nreaders, sizeof(reader_tasks[0]), - GFP_KERNEL); + if (WARN_ONCE(loops > INT_MAX / nreaders, + "%s: nreaders * loops will overflow, adjusted loops to %d", + __func__, INT_MAX / nreaders)) + loops = INT_MAX / nreaders; + reader_tasks = kzalloc_objs(reader_tasks[0], nreaders); if (!reader_tasks) { SCALEOUT_ERRSTRING("out of memory"); firsterr = -ENOMEM; @@ -1244,7 +1581,7 @@ ref_scale_init(void) unwind: torture_init_end(); ref_scale_cleanup(); - if (shutdown) { + if (shutdown_secs) { WARN_ON(!IS_MODULE(CONFIG_RCU_REF_SCALE_TEST)); kernel_power_off(); } |
