X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Frcutorture.c;h=9bb52177af02a3e20aa347e3b65c0a236caa1922;hb=de3f440f8c9922afe8770dd16c84f1c87d779b59;hp=0334b6a8baca35e007c0d509844dc68f64749007;hpb=2326974df29988181b6b69ed6fbf42b17adf916f;p=safe%2Fjmp%2Flinux-2.6 diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 0334b6a..9bb5217 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -18,7 +18,7 @@ * Copyright (C) IBM Corporation, 2005, 2006 * * Authors: Paul E. McKenney - * Josh Triplett + * Josh Triplett * * See also: Documentation/RCU/torture.txt */ @@ -39,17 +39,18 @@ #include #include #include +#include #include #include #include -#include #include #include #include +#include MODULE_LICENSE("GPL"); MODULE_AUTHOR("Paul E. McKenney and " - "Josh Triplett "); + "Josh Triplett "); static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */ static int nfakewriters = 4; /* # fake writer threads */ @@ -57,7 +58,9 @@ static int stat_interval; /* Interval between stats, in seconds. */ /* Defaults to "only at end of test". */ static int verbose; /* Print more debug info. */ static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ -static int shuffle_interval = 5; /* Interval between shuffles (in sec)*/ +static int shuffle_interval = 3; /* Interval between shuffles (in sec)*/ +static int stutter = 5; /* Start/stop testing interval (in sec) */ +static int irqreader = 1; /* RCU readers from irq (timers). */ static char *torture_type = "rcu"; /* What RCU implementation to torture. */ module_param(nreaders, int, 0444); @@ -72,6 +75,10 @@ module_param(test_no_idle_hz, bool, 0444); MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs"); module_param(shuffle_interval, int, 0444); MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles"); +module_param(stutter, int, 0444); +MODULE_PARM_DESC(stutter, "Number of seconds to run/halt test"); +module_param(irqreader, int, 0444); +MODULE_PARM_DESC(irqreader, "Allow RCU readers from irq handlers"); module_param(torture_type, charp, 0444); MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, srcu)"); @@ -91,6 +98,7 @@ static struct task_struct **fakewriter_tasks; static struct task_struct **reader_tasks; static struct task_struct *stats_task; static struct task_struct *shuffler_task; +static struct task_struct *stutter_task; #define RCU_TORTURE_PIPE_LEN 10 @@ -101,10 +109,9 @@ struct rcu_torture { int rtort_mbtest; }; -static int fullstop = 0; /* stop generating callbacks at test end. */ static LIST_HEAD(rcu_torture_freelist); -static struct rcu_torture *rcu_torture_current = NULL; -static long rcu_torture_current_version = 0; +static struct rcu_torture *rcu_torture_current; +static long rcu_torture_current_version; static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; static DEFINE_SPINLOCK(rcu_torture_lock); static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) = @@ -117,7 +124,58 @@ static atomic_t n_rcu_torture_alloc_fail; static atomic_t n_rcu_torture_free; static atomic_t n_rcu_torture_mberror; static atomic_t n_rcu_torture_error; +static long n_rcu_torture_timers; static struct list_head rcu_torture_removed; +static cpumask_var_t shuffle_tmp_mask; + +static int stutter_pause_test; + +#if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE) +#define RCUTORTURE_RUNNABLE_INIT 1 +#else +#define RCUTORTURE_RUNNABLE_INIT 0 +#endif +int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; + +/* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ + +#define FULLSTOP_DONTSTOP 0 /* Normal operation. */ +#define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */ +#define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */ +static int fullstop = FULLSTOP_RMMOD; +DEFINE_MUTEX(fullstop_mutex); /* Protect fullstop transitions and spawning */ + /* of kthreads. */ + +/* + * Detect and respond to a system shutdown. + */ +static int +rcutorture_shutdown_notify(struct notifier_block *unused1, + unsigned long unused2, void *unused3) +{ + mutex_lock(&fullstop_mutex); + if (fullstop == FULLSTOP_DONTSTOP) + fullstop = FULLSTOP_SHUTDOWN; + else + printk(KERN_WARNING /* but going down anyway, so... */ + "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); + mutex_unlock(&fullstop_mutex); + return NOTIFY_DONE; +} + +/* + * Absorb kthreads into a kernel function that won't return, so that + * they won't ever access module text or data again. + */ +static void rcutorture_shutdown_absorb(char *title) +{ + if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) { + printk(KERN_NOTICE + "rcutorture thread %s parking due to system shutdown\n", + title); + schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT); + } +} /* * Allocate an element from the rcu_tortures pool. @@ -179,6 +237,18 @@ rcu_random(struct rcu_random_state *rrsp) return swahw32(rrsp->rrs_state); } +static void +rcu_stutter_wait(char *title) +{ + while (stutter_pause_test || !rcutorture_runnable) { + if (rcutorture_runnable) + schedule_timeout_interruptible(1); + else + schedule_timeout_interruptible(round_jiffies_relative(HZ)); + rcutorture_shutdown_absorb(title); + } +} + /* * Operations vector for selecting different types of tests. */ @@ -187,16 +257,18 @@ struct rcu_torture_ops { void (*init)(void); void (*cleanup)(void); int (*readlock)(void); - void (*readdelay)(struct rcu_random_state *rrsp); + void (*read_delay)(struct rcu_random_state *rrsp); void (*readunlock)(int idx); int (*completed)(void); - void (*deferredfree)(struct rcu_torture *p); + void (*deferred_free)(struct rcu_torture *p); void (*sync)(void); void (*cb_barrier)(void); int (*stats)(char *page); + int irq_capable; char *name; }; -static struct rcu_torture_ops *cur_ops = NULL; + +static struct rcu_torture_ops *cur_ops; /* * Definitions for rcu torture testing. @@ -210,14 +282,17 @@ static int rcu_torture_read_lock(void) __acquires(RCU) static void rcu_read_delay(struct rcu_random_state *rrsp) { - long delay; - const long longdelay = 200; + const unsigned long shortdelay_us = 200; + const unsigned long longdelay_ms = 50; - /* We want there to be long-running readers, but not all the time. */ + /* We want a short delay sometimes to make a reader delay the grace + * period, and we want a long delay occasionally to trigger + * force_quiescent_state. */ - delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay); - if (!delay) - udelay(longdelay); + if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) + mdelay(longdelay_ms); + if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) + udelay(shortdelay_us); } static void rcu_torture_read_unlock(int idx) __releases(RCU) @@ -236,7 +311,7 @@ rcu_torture_cb(struct rcu_head *p) int i; struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); - if (fullstop) { + if (fullstop != FULLSTOP_DONTSTOP) { /* Test is ending, just drop callbacks on the floor. */ /* The next initialization will pick up the pieces. */ return; @@ -249,7 +324,12 @@ rcu_torture_cb(struct rcu_head *p) rp->rtort_mbtest = 0; rcu_torture_free(rp); } else - cur_ops->deferredfree(rp); + cur_ops->deferred_free(rp); +} + +static int rcu_no_completed(void) +{ + return 0; } static void rcu_torture_deferred_free(struct rcu_torture *p) @@ -258,17 +338,18 @@ static void rcu_torture_deferred_free(struct rcu_torture *p) } static struct rcu_torture_ops rcu_ops = { - .init = NULL, - .cleanup = NULL, - .readlock = rcu_torture_read_lock, - .readdelay = rcu_read_delay, - .readunlock = rcu_torture_read_unlock, - .completed = rcu_torture_completed, - .deferredfree = rcu_torture_deferred_free, - .sync = synchronize_rcu, - .cb_barrier = rcu_barrier, - .stats = NULL, - .name = "rcu" + .init = NULL, + .cleanup = NULL, + .readlock = rcu_torture_read_lock, + .read_delay = rcu_read_delay, + .readunlock = rcu_torture_read_unlock, + .completed = rcu_torture_completed, + .deferred_free = rcu_torture_deferred_free, + .sync = synchronize_rcu, + .cb_barrier = rcu_barrier, + .stats = NULL, + .irq_capable = 1, + .name = "rcu" }; static void rcu_sync_torture_deferred_free(struct rcu_torture *p) @@ -298,17 +379,33 @@ static void rcu_sync_torture_init(void) } static struct rcu_torture_ops rcu_sync_ops = { - .init = rcu_sync_torture_init, - .cleanup = NULL, - .readlock = rcu_torture_read_lock, - .readdelay = rcu_read_delay, - .readunlock = rcu_torture_read_unlock, - .completed = rcu_torture_completed, - .deferredfree = rcu_sync_torture_deferred_free, - .sync = synchronize_rcu, - .cb_barrier = NULL, - .stats = NULL, - .name = "rcu_sync" + .init = rcu_sync_torture_init, + .cleanup = NULL, + .readlock = rcu_torture_read_lock, + .read_delay = rcu_read_delay, + .readunlock = rcu_torture_read_unlock, + .completed = rcu_torture_completed, + .deferred_free = rcu_sync_torture_deferred_free, + .sync = synchronize_rcu, + .cb_barrier = NULL, + .stats = NULL, + .irq_capable = 1, + .name = "rcu_sync" +}; + +static struct rcu_torture_ops rcu_expedited_ops = { + .init = rcu_sync_torture_init, + .cleanup = NULL, + .readlock = rcu_torture_read_lock, + .read_delay = rcu_read_delay, /* just reuse rcu's version. */ + .readunlock = rcu_torture_read_unlock, + .completed = rcu_no_completed, + .deferred_free = rcu_sync_torture_deferred_free, + .sync = synchronize_rcu_expedited, + .cb_barrier = NULL, + .stats = NULL, + .irq_capable = 1, + .name = "rcu_expedited" }; /* @@ -359,31 +456,33 @@ static void rcu_bh_torture_synchronize(void) } static struct rcu_torture_ops rcu_bh_ops = { - .init = NULL, - .cleanup = NULL, - .readlock = rcu_bh_torture_read_lock, - .readdelay = rcu_read_delay, /* just reuse rcu's version. */ - .readunlock = rcu_bh_torture_read_unlock, - .completed = rcu_bh_torture_completed, - .deferredfree = rcu_bh_torture_deferred_free, - .sync = rcu_bh_torture_synchronize, - .cb_barrier = rcu_barrier_bh, - .stats = NULL, - .name = "rcu_bh" + .init = NULL, + .cleanup = NULL, + .readlock = rcu_bh_torture_read_lock, + .read_delay = rcu_read_delay, /* just reuse rcu's version. */ + .readunlock = rcu_bh_torture_read_unlock, + .completed = rcu_bh_torture_completed, + .deferred_free = rcu_bh_torture_deferred_free, + .sync = rcu_bh_torture_synchronize, + .cb_barrier = rcu_barrier_bh, + .stats = NULL, + .irq_capable = 1, + .name = "rcu_bh" }; static struct rcu_torture_ops rcu_bh_sync_ops = { - .init = rcu_sync_torture_init, - .cleanup = NULL, - .readlock = rcu_bh_torture_read_lock, - .readdelay = rcu_read_delay, /* just reuse rcu's version. */ - .readunlock = rcu_bh_torture_read_unlock, - .completed = rcu_bh_torture_completed, - .deferredfree = rcu_sync_torture_deferred_free, - .sync = rcu_bh_torture_synchronize, - .cb_barrier = NULL, - .stats = NULL, - .name = "rcu_bh_sync" + .init = rcu_sync_torture_init, + .cleanup = NULL, + .readlock = rcu_bh_torture_read_lock, + .read_delay = rcu_read_delay, /* just reuse rcu's version. */ + .readunlock = rcu_bh_torture_read_unlock, + .completed = rcu_bh_torture_completed, + .deferred_free = rcu_sync_torture_deferred_free, + .sync = rcu_bh_torture_synchronize, + .cb_barrier = NULL, + .stats = NULL, + .irq_capable = 1, + .name = "rcu_bh_sync" }; /* @@ -455,17 +554,36 @@ static int srcu_torture_stats(char *page) } static struct rcu_torture_ops srcu_ops = { - .init = srcu_torture_init, - .cleanup = srcu_torture_cleanup, - .readlock = srcu_torture_read_lock, - .readdelay = srcu_read_delay, - .readunlock = srcu_torture_read_unlock, - .completed = srcu_torture_completed, - .deferredfree = rcu_sync_torture_deferred_free, - .sync = srcu_torture_synchronize, - .cb_barrier = NULL, - .stats = srcu_torture_stats, - .name = "srcu" + .init = srcu_torture_init, + .cleanup = srcu_torture_cleanup, + .readlock = srcu_torture_read_lock, + .read_delay = srcu_read_delay, + .readunlock = srcu_torture_read_unlock, + .completed = srcu_torture_completed, + .deferred_free = rcu_sync_torture_deferred_free, + .sync = srcu_torture_synchronize, + .cb_barrier = NULL, + .stats = srcu_torture_stats, + .name = "srcu" +}; + +static void srcu_torture_synchronize_expedited(void) +{ + synchronize_srcu_expedited(&srcu_ctl); +} + +static struct rcu_torture_ops srcu_expedited_ops = { + .init = srcu_torture_init, + .cleanup = srcu_torture_cleanup, + .readlock = srcu_torture_read_lock, + .read_delay = srcu_read_delay, + .readunlock = srcu_torture_read_unlock, + .completed = srcu_torture_completed, + .deferred_free = rcu_sync_torture_deferred_free, + .sync = srcu_torture_synchronize_expedited, + .cb_barrier = NULL, + .stats = srcu_torture_stats, + .name = "srcu_expedited" }; /* @@ -483,11 +601,6 @@ static void sched_torture_read_unlock(int idx) preempt_enable(); } -static int sched_torture_completed(void) -{ - return 0; -} - static void rcu_sched_torture_deferred_free(struct rcu_torture *p) { call_rcu_sched(&p->rtort_rcu, rcu_torture_cb); @@ -499,31 +612,47 @@ static void sched_torture_synchronize(void) } static struct rcu_torture_ops sched_ops = { - .init = rcu_sync_torture_init, - .cleanup = NULL, - .readlock = sched_torture_read_lock, - .readdelay = rcu_read_delay, /* just reuse rcu's version. */ - .readunlock = sched_torture_read_unlock, - .completed = sched_torture_completed, - .deferredfree = rcu_sched_torture_deferred_free, - .sync = sched_torture_synchronize, - .cb_barrier = rcu_barrier_sched, - .stats = NULL, - .name = "sched" + .init = rcu_sync_torture_init, + .cleanup = NULL, + .readlock = sched_torture_read_lock, + .read_delay = rcu_read_delay, /* just reuse rcu's version. */ + .readunlock = sched_torture_read_unlock, + .completed = rcu_no_completed, + .deferred_free = rcu_sched_torture_deferred_free, + .sync = sched_torture_synchronize, + .cb_barrier = rcu_barrier_sched, + .stats = NULL, + .irq_capable = 1, + .name = "sched" +}; + +static struct rcu_torture_ops sched_sync_ops = { + .init = rcu_sync_torture_init, + .cleanup = NULL, + .readlock = sched_torture_read_lock, + .read_delay = rcu_read_delay, /* just reuse rcu's version. */ + .readunlock = sched_torture_read_unlock, + .completed = rcu_no_completed, + .deferred_free = rcu_sync_torture_deferred_free, + .sync = sched_torture_synchronize, + .cb_barrier = NULL, + .stats = NULL, + .name = "sched_sync" }; -static struct rcu_torture_ops sched_ops_sync = { - .init = rcu_sync_torture_init, - .cleanup = NULL, - .readlock = sched_torture_read_lock, - .readdelay = rcu_read_delay, /* just reuse rcu's version. */ - .readunlock = sched_torture_read_unlock, - .completed = sched_torture_completed, - .deferredfree = rcu_sync_torture_deferred_free, - .sync = sched_torture_synchronize, - .cb_barrier = NULL, - .stats = NULL, - .name = "sched_sync" +static struct rcu_torture_ops sched_expedited_ops = { + .init = rcu_sync_torture_init, + .cleanup = NULL, + .readlock = sched_torture_read_lock, + .read_delay = rcu_read_delay, /* just reuse rcu's version. */ + .readunlock = sched_torture_read_unlock, + .completed = rcu_no_completed, + .deferred_free = rcu_sync_torture_deferred_free, + .sync = synchronize_sched_expedited, + .cb_barrier = NULL, + .stats = rcu_expedited_torture_stats, + .irq_capable = 1, + .name = "sched_expedited" }; /* @@ -545,26 +674,29 @@ rcu_torture_writer(void *arg) do { schedule_timeout_uninterruptible(1); - if ((rp = rcu_torture_alloc()) == NULL) + rp = rcu_torture_alloc(); + if (rp == NULL) continue; rp->rtort_pipe_count = 0; udelay(rcu_random(&rand) & 0x3ff); old_rp = rcu_torture_current; rp->rtort_mbtest = 1; rcu_assign_pointer(rcu_torture_current, rp); - smp_wmb(); + smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */ if (old_rp) { i = old_rp->rtort_pipe_count; if (i > RCU_TORTURE_PIPE_LEN) i = RCU_TORTURE_PIPE_LEN; atomic_inc(&rcu_torture_wcount[i]); old_rp->rtort_pipe_count++; - cur_ops->deferredfree(old_rp); + cur_ops->deferred_free(old_rp); } rcu_torture_current_version++; oldbatch = cur_ops->completed(); - } while (!kthread_should_stop() && !fullstop); + rcu_stutter_wait("rcu_torture_writer"); + } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping"); + rcutorture_shutdown_absorb("rcu_torture_writer"); while (!kthread_should_stop()) schedule_timeout_uninterruptible(1); return 0; @@ -586,15 +718,63 @@ rcu_torture_fakewriter(void *arg) schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); udelay(rcu_random(&rand) & 0x3ff); cur_ops->sync(); - } while (!kthread_should_stop() && !fullstop); + rcu_stutter_wait("rcu_torture_fakewriter"); + } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping"); + rcutorture_shutdown_absorb("rcu_torture_fakewriter"); while (!kthread_should_stop()) schedule_timeout_uninterruptible(1); return 0; } /* + * RCU torture reader from timer handler. Dereferences rcu_torture_current, + * incrementing the corresponding element of the pipeline array. The + * counter in the element should never be greater than 1, otherwise, the + * RCU implementation is broken. + */ +static void rcu_torture_timer(unsigned long unused) +{ + int idx; + int completed; + static DEFINE_RCU_RANDOM(rand); + static DEFINE_SPINLOCK(rand_lock); + struct rcu_torture *p; + int pipe_count; + + idx = cur_ops->readlock(); + completed = cur_ops->completed(); + p = rcu_dereference(rcu_torture_current); + if (p == NULL) { + /* Leave because rcu_torture_writer is not yet underway */ + cur_ops->readunlock(idx); + return; + } + if (p->rtort_mbtest == 0) + atomic_inc(&n_rcu_torture_mberror); + spin_lock(&rand_lock); + cur_ops->read_delay(&rand); + n_rcu_torture_timers++; + spin_unlock(&rand_lock); + preempt_disable(); + pipe_count = p->rtort_pipe_count; + if (pipe_count > RCU_TORTURE_PIPE_LEN) { + /* Should not happen, but... */ + pipe_count = RCU_TORTURE_PIPE_LEN; + } + __this_cpu_inc(per_cpu_var(rcu_torture_count)[pipe_count]); + completed = cur_ops->completed() - completed; + if (completed > RCU_TORTURE_PIPE_LEN) { + /* Should not happen, but... */ + completed = RCU_TORTURE_PIPE_LEN; + } + __this_cpu_inc(per_cpu_var(rcu_torture_batch)[completed]); + preempt_enable(); + cur_ops->readunlock(idx); +} + +/* * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, * incrementing the corresponding element of the pipeline array. The * counter in the element should never be greater than 1, otherwise, the @@ -608,11 +788,18 @@ rcu_torture_reader(void *arg) DEFINE_RCU_RANDOM(rand); struct rcu_torture *p; int pipe_count; + struct timer_list t; VERBOSE_PRINTK_STRING("rcu_torture_reader task started"); set_user_nice(current, 19); + if (irqreader && cur_ops->irq_capable) + setup_timer_on_stack(&t, rcu_torture_timer, 0); do { + if (irqreader && cur_ops->irq_capable) { + if (!timer_pending(&t)) + mod_timer(&t, 1); + } idx = cur_ops->readlock(); completed = cur_ops->completed(); p = rcu_dereference(rcu_torture_current); @@ -624,25 +811,29 @@ rcu_torture_reader(void *arg) } if (p->rtort_mbtest == 0) atomic_inc(&n_rcu_torture_mberror); - cur_ops->readdelay(&rand); + cur_ops->read_delay(&rand); preempt_disable(); pipe_count = p->rtort_pipe_count; if (pipe_count > RCU_TORTURE_PIPE_LEN) { /* Should not happen, but... */ pipe_count = RCU_TORTURE_PIPE_LEN; } - ++__get_cpu_var(rcu_torture_count)[pipe_count]; + __this_cpu_inc(per_cpu_var(rcu_torture_count)[pipe_count]); completed = cur_ops->completed() - completed; if (completed > RCU_TORTURE_PIPE_LEN) { /* Should not happen, but... */ completed = RCU_TORTURE_PIPE_LEN; } - ++__get_cpu_var(rcu_torture_batch)[completed]; + __this_cpu_inc(per_cpu_var(rcu_torture_batch)[completed]); preempt_enable(); cur_ops->readunlock(idx); schedule(); - } while (!kthread_should_stop() && !fullstop); + rcu_stutter_wait("rcu_torture_reader"); + } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping"); + rcutorture_shutdown_absorb("rcu_torture_reader"); + if (irqreader && cur_ops->irq_capable) + del_timer_sync(&t); while (!kthread_should_stop()) schedule_timeout_uninterruptible(1); return 0; @@ -673,20 +864,22 @@ rcu_torture_printk(char *page) cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); cnt += sprintf(&page[cnt], "rtc: %p ver: %ld tfle: %d rta: %d rtaf: %d rtf: %d " - "rtmbe: %d", + "rtmbe: %d nt: %ld", rcu_torture_current, rcu_torture_current_version, list_empty(&rcu_torture_freelist), atomic_read(&n_rcu_torture_alloc), atomic_read(&n_rcu_torture_alloc_fail), atomic_read(&n_rcu_torture_free), - atomic_read(&n_rcu_torture_mberror)); + atomic_read(&n_rcu_torture_mberror), + n_rcu_torture_timers); if (atomic_read(&n_rcu_torture_mberror) != 0) cnt += sprintf(&page[cnt], " !!!"); cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); if (i > 1) { cnt += sprintf(&page[cnt], "!!! "); atomic_inc(&n_rcu_torture_error); + WARN_ON_ONCE(1); } cnt += sprintf(&page[cnt], "Reader Pipe: "); for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) @@ -738,6 +931,7 @@ rcu_torture_stats(void *arg) do { schedule_timeout_interruptible(stat_interval * HZ); rcu_torture_stats_print(); + rcutorture_shutdown_absorb("rcu_torture_stats"); } while (!kthread_should_stop()); VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping"); return 0; @@ -750,10 +944,9 @@ static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ */ static void rcu_torture_shuffle_tasks(void) { - cpumask_t tmp_mask; int i; - cpus_setall(tmp_mask); + cpumask_setall(shuffle_tmp_mask); get_online_cpus(); /* No point in shuffling if there is only one online CPU (ex: UP) */ @@ -763,29 +956,29 @@ static void rcu_torture_shuffle_tasks(void) } if (rcu_idle_cpu != -1) - cpu_clear(rcu_idle_cpu, tmp_mask); + cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask); - set_cpus_allowed_ptr(current, &tmp_mask); + set_cpus_allowed_ptr(current, shuffle_tmp_mask); if (reader_tasks) { for (i = 0; i < nrealreaders; i++) if (reader_tasks[i]) set_cpus_allowed_ptr(reader_tasks[i], - &tmp_mask); + shuffle_tmp_mask); } if (fakewriter_tasks) { for (i = 0; i < nfakewriters; i++) if (fakewriter_tasks[i]) set_cpus_allowed_ptr(fakewriter_tasks[i], - &tmp_mask); + shuffle_tmp_mask); } if (writer_task) - set_cpus_allowed_ptr(writer_task, &tmp_mask); + set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask); if (stats_task) - set_cpus_allowed_ptr(stats_task, &tmp_mask); + set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask); if (rcu_idle_cpu == -1) rcu_idle_cpu = num_online_cpus() - 1; @@ -806,31 +999,74 @@ rcu_torture_shuffle(void *arg) do { schedule_timeout_interruptible(shuffle_interval * HZ); rcu_torture_shuffle_tasks(); + rcutorture_shutdown_absorb("rcu_torture_shuffle"); } while (!kthread_should_stop()); VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); return 0; } +/* Cause the rcutorture test to "stutter", starting and stopping all + * threads periodically. + */ +static int +rcu_torture_stutter(void *arg) +{ + VERBOSE_PRINTK_STRING("rcu_torture_stutter task started"); + do { + schedule_timeout_interruptible(stutter * HZ); + stutter_pause_test = 1; + if (!kthread_should_stop()) + schedule_timeout_interruptible(stutter * HZ); + stutter_pause_test = 0; + rcutorture_shutdown_absorb("rcu_torture_stutter"); + } while (!kthread_should_stop()); + VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping"); + return 0; +} + static inline void rcu_torture_print_module_parms(char *tag) { printk(KERN_ALERT "%s" TORTURE_FLAG "--- %s: nreaders=%d nfakewriters=%d " "stat_interval=%d verbose=%d test_no_idle_hz=%d " - "shuffle_interval = %d\n", + "shuffle_interval=%d stutter=%d irqreader=%d\n", torture_type, tag, nrealreaders, nfakewriters, - stat_interval, verbose, test_no_idle_hz, shuffle_interval); + stat_interval, verbose, test_no_idle_hz, shuffle_interval, + stutter, irqreader); } +static struct notifier_block rcutorture_nb = { + .notifier_call = rcutorture_shutdown_notify, +}; + static void rcu_torture_cleanup(void) { int i; - fullstop = 1; + mutex_lock(&fullstop_mutex); + if (fullstop == FULLSTOP_SHUTDOWN) { + printk(KERN_WARNING /* but going down anyway, so... */ + "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); + mutex_unlock(&fullstop_mutex); + schedule_timeout_uninterruptible(10); + if (cur_ops->cb_barrier != NULL) + cur_ops->cb_barrier(); + return; + } + fullstop = FULLSTOP_RMMOD; + mutex_unlock(&fullstop_mutex); + unregister_reboot_notifier(&rcutorture_nb); + if (stutter_task) { + VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task"); + kthread_stop(stutter_task); + } + stutter_task = NULL; if (shuffler_task) { VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); kthread_stop(shuffler_task); + free_cpumask_var(shuffle_tmp_mask); } shuffler_task = NULL; @@ -895,8 +1131,12 @@ rcu_torture_init(void) int cpu; int firsterr = 0; static struct rcu_torture_ops *torture_ops[] = - { &rcu_ops, &rcu_sync_ops, &rcu_bh_ops, &rcu_bh_sync_ops, - &srcu_ops, &sched_ops, &sched_ops_sync, }; + { &rcu_ops, &rcu_sync_ops, &rcu_expedited_ops, + &rcu_bh_ops, &rcu_bh_sync_ops, + &srcu_ops, &srcu_expedited_ops, + &sched_ops, &sched_sync_ops, &sched_expedited_ops, }; + + mutex_lock(&fullstop_mutex); /* Process args and tell the world that the torturer is on the job. */ for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { @@ -905,9 +1145,14 @@ rcu_torture_init(void) break; } if (i == ARRAY_SIZE(torture_ops)) { - printk(KERN_ALERT "rcutorture: invalid torture type: \"%s\"\n", + printk(KERN_ALERT "rcu-torture: invalid torture type: \"%s\"\n", torture_type); - return (-EINVAL); + printk(KERN_ALERT "rcu-torture types:"); + for (i = 0; i < ARRAY_SIZE(torture_ops); i++) + printk(KERN_ALERT " %s", torture_ops[i]->name); + printk(KERN_ALERT "\n"); + mutex_unlock(&fullstop_mutex); + return -EINVAL; } if (cur_ops->init) cur_ops->init(); /* no "goto unwind" prior to this point!!! */ @@ -917,7 +1162,7 @@ rcu_torture_init(void) else nrealreaders = 2 * num_online_cpus(); rcu_torture_print_module_parms("Start of test"); - fullstop = 0; + fullstop = FULLSTOP_DONTSTOP; /* Set up the freelist. */ @@ -958,7 +1203,7 @@ rcu_torture_init(void) goto unwind; } fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), - GFP_KERNEL); + GFP_KERNEL); if (fakewriter_tasks == NULL) { VERBOSE_PRINTK_ERRSTRING("out of memory"); firsterr = -ENOMEM; @@ -967,7 +1212,7 @@ rcu_torture_init(void) for (i = 0; i < nfakewriters; i++) { VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task"); fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL, - "rcu_torture_fakewriter"); + "rcu_torture_fakewriter"); if (IS_ERR(fakewriter_tasks[i])) { firsterr = PTR_ERR(fakewriter_tasks[i]); VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter"); @@ -1006,19 +1251,43 @@ rcu_torture_init(void) } if (test_no_idle_hz) { rcu_idle_cpu = num_online_cpus() - 1; + + if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) { + firsterr = -ENOMEM; + VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask"); + goto unwind; + } + /* Create the shuffler thread */ shuffler_task = kthread_run(rcu_torture_shuffle, NULL, "rcu_torture_shuffle"); if (IS_ERR(shuffler_task)) { + free_cpumask_var(shuffle_tmp_mask); firsterr = PTR_ERR(shuffler_task); VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); shuffler_task = NULL; goto unwind; } } + if (stutter < 0) + stutter = 0; + if (stutter) { + /* Create the stutter thread */ + stutter_task = kthread_run(rcu_torture_stutter, NULL, + "rcu_torture_stutter"); + if (IS_ERR(stutter_task)) { + firsterr = PTR_ERR(stutter_task); + VERBOSE_PRINTK_ERRSTRING("Failed to create stutter"); + stutter_task = NULL; + goto unwind; + } + } + register_reboot_notifier(&rcutorture_nb); + mutex_unlock(&fullstop_mutex); return 0; unwind: + mutex_unlock(&fullstop_mutex); rcu_torture_cleanup(); return firsterr; }