// SPDX-License-Identifier: GPL-2.0+
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/*
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* Read-Copy Update module-based scalability-test facility
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*
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* Copyright (C) IBM Corporation, 2015
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*
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* Authors: Paul E. McKenney <paulmck@linux.ibm.com>
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*/
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#define pr_fmt(fmt) fmt
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/module.h>
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#include <linux/kthread.h>
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#include <linux/err.h>
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#include <linux/spinlock.h>
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#include <linux/smp.h>
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#include <linux/rcupdate.h>
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#include <linux/interrupt.h>
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#include <linux/sched.h>
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#include <uapi/linux/sched/types.h>
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#include <linux/atomic.h>
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#include <linux/bitops.h>
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#include <linux/completion.h>
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#include <linux/moduleparam.h>
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#include <linux/percpu.h>
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#include <linux/notifier.h>
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#include <linux/reboot.h>
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#include <linux/freezer.h>
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#include <linux/cpu.h>
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#include <linux/delay.h>
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#include <linux/stat.h>
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#include <linux/srcu.h>
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#include <linux/slab.h>
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#include <asm/byteorder.h>
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#include <linux/torture.h>
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#include <linux/vmalloc.h>
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#include "rcu.h"
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>");
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#define SCALE_FLAG "-scale:"
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#define SCALEOUT_STRING(s) \
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pr_alert("%s" SCALE_FLAG " %s\n", scale_type, s)
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#define VERBOSE_SCALEOUT_STRING(s) \
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do { if (verbose) pr_alert("%s" SCALE_FLAG " %s\n", scale_type, s); } while (0)
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#define VERBOSE_SCALEOUT_ERRSTRING(s) \
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do { if (verbose) pr_alert("%s" SCALE_FLAG "!!! %s\n", scale_type, s); } while (0)
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/*
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* The intended use cases for the nreaders and nwriters module parameters
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* are as follows:
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*
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* 1. Specify only the nr_cpus kernel boot parameter. This will
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* set both nreaders and nwriters to the value specified by
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* nr_cpus for a mixed reader/writer test.
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*
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* 2. Specify the nr_cpus kernel boot parameter, but set
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* rcuscale.nreaders to zero. This will set nwriters to the
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* value specified by nr_cpus for an update-only test.
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*
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* 3. Specify the nr_cpus kernel boot parameter, but set
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* rcuscale.nwriters to zero. This will set nreaders to the
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* value specified by nr_cpus for a read-only test.
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*
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* Various other use cases may of course be specified.
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*
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* Note that this test's readers are intended only as a test load for
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* the writers. The reader scalability statistics will be overly
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* pessimistic due to the per-critical-section interrupt disabling,
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* test-end checks, and the pair of calls through pointers.
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*/
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#ifdef MODULE
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# define RCUSCALE_SHUTDOWN 0
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#else
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# define RCUSCALE_SHUTDOWN 1
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#endif
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torture_param(bool, gp_async, false, "Use asynchronous GP wait primitives");
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torture_param(int, gp_async_max, 1000, "Max # outstanding waits per reader");
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torture_param(bool, gp_exp, false, "Use expedited GP wait primitives");
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torture_param(int, holdoff, 10, "Holdoff time before test start (s)");
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torture_param(int, nreaders, -1, "Number of RCU reader threads");
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torture_param(int, nwriters, -1, "Number of RCU updater threads");
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torture_param(bool, shutdown, RCUSCALE_SHUTDOWN,
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"Shutdown at end of scalability tests.");
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torture_param(int, verbose, 1, "Enable verbose debugging printk()s");
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torture_param(int, writer_holdoff, 0, "Holdoff (us) between GPs, zero to disable");
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torture_param(int, kfree_rcu_test, 0, "Do we run a kfree_rcu() scale test?");
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torture_param(int, kfree_mult, 1, "Multiple of kfree_obj size to allocate.");
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static char *scale_type = "rcu";
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module_param(scale_type, charp, 0444);
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MODULE_PARM_DESC(scale_type, "Type of RCU to scalability-test (rcu, srcu, ...)");
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static int nrealreaders;
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static int nrealwriters;
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static struct task_struct **writer_tasks;
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static struct task_struct **reader_tasks;
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static struct task_struct *shutdown_task;
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static u64 **writer_durations;
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static int *writer_n_durations;
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static atomic_t n_rcu_scale_reader_started;
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static atomic_t n_rcu_scale_writer_started;
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static atomic_t n_rcu_scale_writer_finished;
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static wait_queue_head_t shutdown_wq;
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static u64 t_rcu_scale_writer_started;
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static u64 t_rcu_scale_writer_finished;
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static unsigned long b_rcu_gp_test_started;
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static unsigned long b_rcu_gp_test_finished;
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static DEFINE_PER_CPU(atomic_t, n_async_inflight);
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#define MAX_MEAS 10000
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#define MIN_MEAS 100
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/*
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* Operations vector for selecting different types of tests.
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*/
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struct rcu_scale_ops {
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int ptype;
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void (*init)(void);
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void (*cleanup)(void);
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int (*readlock)(void);
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void (*readunlock)(int idx);
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unsigned long (*get_gp_seq)(void);
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unsigned long (*gp_diff)(unsigned long new, unsigned long old);
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unsigned long (*exp_completed)(void);
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void (*async)(struct rcu_head *head, rcu_callback_t func);
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void (*gp_barrier)(void);
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void (*sync)(void);
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void (*exp_sync)(void);
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const char *name;
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};
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static struct rcu_scale_ops *cur_ops;
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/*
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* Definitions for rcu scalability testing.
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*/
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static int rcu_scale_read_lock(void) __acquires(RCU)
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{
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rcu_read_lock();
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return 0;
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}
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static void rcu_scale_read_unlock(int idx) __releases(RCU)
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{
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rcu_read_unlock();
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}
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static unsigned long __maybe_unused rcu_no_completed(void)
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{
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return 0;
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}
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static void rcu_sync_scale_init(void)
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{
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}
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static struct rcu_scale_ops rcu_ops = {
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.ptype = RCU_FLAVOR,
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.init = rcu_sync_scale_init,
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.readlock = rcu_scale_read_lock,
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.readunlock = rcu_scale_read_unlock,
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.get_gp_seq = rcu_get_gp_seq,
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.gp_diff = rcu_seq_diff,
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.exp_completed = rcu_exp_batches_completed,
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.async = call_rcu,
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.gp_barrier = rcu_barrier,
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.sync = synchronize_rcu,
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.exp_sync = synchronize_rcu_expedited,
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.name = "rcu"
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};
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/*
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* Definitions for srcu scalability testing.
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*/
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DEFINE_STATIC_SRCU(srcu_ctl_scale);
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static struct srcu_struct *srcu_ctlp = &srcu_ctl_scale;
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static int srcu_scale_read_lock(void) __acquires(srcu_ctlp)
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{
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return srcu_read_lock(srcu_ctlp);
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}
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static void srcu_scale_read_unlock(int idx) __releases(srcu_ctlp)
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{
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srcu_read_unlock(srcu_ctlp, idx);
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}
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static unsigned long srcu_scale_completed(void)
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{
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return srcu_batches_completed(srcu_ctlp);
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}
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static void srcu_call_rcu(struct rcu_head *head, rcu_callback_t func)
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{
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call_srcu(srcu_ctlp, head, func);
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}
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static void srcu_rcu_barrier(void)
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{
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srcu_barrier(srcu_ctlp);
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}
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static void srcu_scale_synchronize(void)
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{
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synchronize_srcu(srcu_ctlp);
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}
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static void srcu_scale_synchronize_expedited(void)
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{
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synchronize_srcu_expedited(srcu_ctlp);
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}
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static struct rcu_scale_ops srcu_ops = {
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.ptype = SRCU_FLAVOR,
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.init = rcu_sync_scale_init,
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.readlock = srcu_scale_read_lock,
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.readunlock = srcu_scale_read_unlock,
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.get_gp_seq = srcu_scale_completed,
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.gp_diff = rcu_seq_diff,
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.exp_completed = srcu_scale_completed,
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.async = srcu_call_rcu,
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.gp_barrier = srcu_rcu_barrier,
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.sync = srcu_scale_synchronize,
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.exp_sync = srcu_scale_synchronize_expedited,
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.name = "srcu"
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};
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static struct srcu_struct srcud;
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static void srcu_sync_scale_init(void)
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{
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srcu_ctlp = &srcud;
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init_srcu_struct(srcu_ctlp);
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}
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static void srcu_sync_scale_cleanup(void)
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{
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cleanup_srcu_struct(srcu_ctlp);
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}
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static struct rcu_scale_ops srcud_ops = {
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.ptype = SRCU_FLAVOR,
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.init = srcu_sync_scale_init,
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.cleanup = srcu_sync_scale_cleanup,
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.readlock = srcu_scale_read_lock,
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.readunlock = srcu_scale_read_unlock,
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.get_gp_seq = srcu_scale_completed,
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.gp_diff = rcu_seq_diff,
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.exp_completed = srcu_scale_completed,
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.async = srcu_call_rcu,
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.gp_barrier = srcu_rcu_barrier,
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.sync = srcu_scale_synchronize,
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.exp_sync = srcu_scale_synchronize_expedited,
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.name = "srcud"
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};
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/*
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* Definitions for RCU-tasks scalability testing.
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*/
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static int tasks_scale_read_lock(void)
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{
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return 0;
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}
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static void tasks_scale_read_unlock(int idx)
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{
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}
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static struct rcu_scale_ops tasks_ops = {
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.ptype = RCU_TASKS_FLAVOR,
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.init = rcu_sync_scale_init,
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.readlock = tasks_scale_read_lock,
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.readunlock = tasks_scale_read_unlock,
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.get_gp_seq = rcu_no_completed,
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.gp_diff = rcu_seq_diff,
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.async = call_rcu_tasks,
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.gp_barrier = rcu_barrier_tasks,
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.sync = synchronize_rcu_tasks,
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.exp_sync = synchronize_rcu_tasks,
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.name = "tasks"
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};
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static unsigned long rcuscale_seq_diff(unsigned long new, unsigned long old)
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{
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if (!cur_ops->gp_diff)
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return new - old;
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return cur_ops->gp_diff(new, old);
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}
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/*
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* If scalability tests complete, wait for shutdown to commence.
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*/
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static void rcu_scale_wait_shutdown(void)
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{
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cond_resched_tasks_rcu_qs();
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if (atomic_read(&n_rcu_scale_writer_finished) < nrealwriters)
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return;
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while (!torture_must_stop())
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schedule_timeout_uninterruptible(1);
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}
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/*
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* RCU scalability reader kthread. Repeatedly does empty RCU read-side
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* critical section, minimizing update-side interference. However, the
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* point of this test is not to evaluate reader scalability, but instead
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* to serve as a test load for update-side scalability testing.
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*/
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static int
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rcu_scale_reader(void *arg)
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{
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unsigned long flags;
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int idx;
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long me = (long)arg;
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VERBOSE_SCALEOUT_STRING("rcu_scale_reader task started");
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set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids));
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set_user_nice(current, MAX_NICE);
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atomic_inc(&n_rcu_scale_reader_started);
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do {
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local_irq_save(flags);
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idx = cur_ops->readlock();
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cur_ops->readunlock(idx);
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local_irq_restore(flags);
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rcu_scale_wait_shutdown();
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} while (!torture_must_stop());
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torture_kthread_stopping("rcu_scale_reader");
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return 0;
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}
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/*
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* Callback function for asynchronous grace periods from rcu_scale_writer().
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*/
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static void rcu_scale_async_cb(struct rcu_head *rhp)
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{
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atomic_dec(this_cpu_ptr(&n_async_inflight));
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kfree(rhp);
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}
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/*
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* RCU scale writer kthread. Repeatedly does a grace period.
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*/
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static int
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rcu_scale_writer(void *arg)
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{
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int i = 0;
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int i_max;
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long me = (long)arg;
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struct rcu_head *rhp = NULL;
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bool started = false, done = false, alldone = false;
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u64 t;
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u64 *wdp;
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u64 *wdpp = writer_durations[me];
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VERBOSE_SCALEOUT_STRING("rcu_scale_writer task started");
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WARN_ON(!wdpp);
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set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids));
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sched_set_fifo_low(current);
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if (holdoff)
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schedule_timeout_uninterruptible(holdoff * HZ);
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/*
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* Wait until rcu_end_inkernel_boot() is called for normal GP tests
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* so that RCU is not always expedited for normal GP tests.
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* The system_state test is approximate, but works well in practice.
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*/
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while (!gp_exp && system_state != SYSTEM_RUNNING)
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schedule_timeout_uninterruptible(1);
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t = ktime_get_mono_fast_ns();
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if (atomic_inc_return(&n_rcu_scale_writer_started) >= nrealwriters) {
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t_rcu_scale_writer_started = t;
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if (gp_exp) {
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b_rcu_gp_test_started =
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cur_ops->exp_completed() / 2;
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} else {
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b_rcu_gp_test_started = cur_ops->get_gp_seq();
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}
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}
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do {
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if (writer_holdoff)
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udelay(writer_holdoff);
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wdp = &wdpp[i];
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*wdp = ktime_get_mono_fast_ns();
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if (gp_async) {
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retry:
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if (!rhp)
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rhp = kmalloc(sizeof(*rhp), GFP_KERNEL);
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if (rhp && atomic_read(this_cpu_ptr(&n_async_inflight)) < gp_async_max) {
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atomic_inc(this_cpu_ptr(&n_async_inflight));
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cur_ops->async(rhp, rcu_scale_async_cb);
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rhp = NULL;
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} else if (!kthread_should_stop()) {
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cur_ops->gp_barrier();
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goto retry;
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} else {
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kfree(rhp); /* Because we are stopping. */
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}
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} else if (gp_exp) {
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cur_ops->exp_sync();
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} else {
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cur_ops->sync();
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}
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t = ktime_get_mono_fast_ns();
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*wdp = t - *wdp;
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i_max = i;
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if (!started &&
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atomic_read(&n_rcu_scale_writer_started) >= nrealwriters)
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started = true;
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if (!done && i >= MIN_MEAS) {
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done = true;
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sched_set_normal(current, 0);
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pr_alert("%s%s rcu_scale_writer %ld has %d measurements\n",
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scale_type, SCALE_FLAG, me, MIN_MEAS);
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if (atomic_inc_return(&n_rcu_scale_writer_finished) >=
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nrealwriters) {
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schedule_timeout_interruptible(10);
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rcu_ftrace_dump(DUMP_ALL);
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SCALEOUT_STRING("Test complete");
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t_rcu_scale_writer_finished = t;
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if (gp_exp) {
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b_rcu_gp_test_finished =
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cur_ops->exp_completed() / 2;
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} else {
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b_rcu_gp_test_finished =
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cur_ops->get_gp_seq();
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}
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if (shutdown) {
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smp_mb(); /* Assign before wake. */
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wake_up(&shutdown_wq);
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}
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}
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}
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if (done && !alldone &&
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atomic_read(&n_rcu_scale_writer_finished) >= nrealwriters)
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alldone = true;
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if (started && !alldone && i < MAX_MEAS - 1)
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i++;
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rcu_scale_wait_shutdown();
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} while (!torture_must_stop());
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if (gp_async) {
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cur_ops->gp_barrier();
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}
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writer_n_durations[me] = i_max;
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torture_kthread_stopping("rcu_scale_writer");
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return 0;
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}
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static void
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rcu_scale_print_module_parms(struct rcu_scale_ops *cur_ops, const char *tag)
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{
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pr_alert("%s" SCALE_FLAG
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"--- %s: nreaders=%d nwriters=%d verbose=%d shutdown=%d\n",
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scale_type, tag, nrealreaders, nrealwriters, verbose, shutdown);
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}
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static void
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rcu_scale_cleanup(void)
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{
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int i;
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int j;
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int ngps = 0;
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u64 *wdp;
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u64 *wdpp;
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/*
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* Would like warning at start, but everything is expedited
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* during the mid-boot phase, so have to wait till the end.
|
*/
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if (rcu_gp_is_expedited() && !rcu_gp_is_normal() && !gp_exp)
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VERBOSE_SCALEOUT_ERRSTRING("All grace periods expedited, no normal ones to measure!");
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if (rcu_gp_is_normal() && gp_exp)
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VERBOSE_SCALEOUT_ERRSTRING("All grace periods normal, no expedited ones to measure!");
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if (gp_exp && gp_async)
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VERBOSE_SCALEOUT_ERRSTRING("No expedited async GPs, so went with async!");
|
|
if (torture_cleanup_begin())
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return;
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if (!cur_ops) {
|
torture_cleanup_end();
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return;
|
}
|
|
if (reader_tasks) {
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for (i = 0; i < nrealreaders; i++)
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torture_stop_kthread(rcu_scale_reader,
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reader_tasks[i]);
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kfree(reader_tasks);
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}
|
|
if (writer_tasks) {
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for (i = 0; i < nrealwriters; i++) {
|
torture_stop_kthread(rcu_scale_writer,
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writer_tasks[i]);
|
if (!writer_n_durations)
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continue;
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j = writer_n_durations[i];
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pr_alert("%s%s writer %d gps: %d\n",
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scale_type, SCALE_FLAG, i, j);
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ngps += j;
|
}
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pr_alert("%s%s start: %llu end: %llu duration: %llu gps: %d batches: %ld\n",
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scale_type, SCALE_FLAG,
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t_rcu_scale_writer_started, t_rcu_scale_writer_finished,
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t_rcu_scale_writer_finished -
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t_rcu_scale_writer_started,
|
ngps,
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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.");
|
|
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;
|
|
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);
|
|
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;
|
|
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 (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 (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,
|
};
|
|
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");
|
WARN_ON(!IS_MODULE(CONFIG_RCU_SCALE_TEST));
|
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 (firsterr)
|
goto unwind;
|
schedule_timeout_uninterruptible(1);
|
}
|
reader_tasks = kcalloc(nrealreaders, sizeof(reader_tasks[0]),
|
GFP_KERNEL);
|
if (reader_tasks == NULL) {
|
VERBOSE_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 (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) {
|
VERBOSE_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 (firsterr)
|
goto unwind;
|
}
|
torture_init_end();
|
return 0;
|
|
unwind:
|
torture_init_end();
|
rcu_scale_cleanup();
|
return firsterr;
|
}
|
|
module_init(rcu_scale_init);
|
module_exit(rcu_scale_cleanup);
|
