diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/pid_namespace.c | 6 | ||||
| -rw-r--r-- | kernel/sched/core.c | 39 | ||||
| -rw-r--r-- | kernel/sched/fair.c | 28 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 19 | ||||
| -rw-r--r-- | kernel/workqueue.c | 37 |
5 files changed, 57 insertions, 72 deletions
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index baa528d7dfbd..478bad2745e3 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -234,15 +234,19 @@ static int pid_ns_ctl_handler(struct ctl_table *table, int write, */ tmp.data = ¤t->nsproxy->pid_ns->last_pid; - return proc_dointvec(&tmp, write, buffer, lenp, ppos); + return proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); } +extern int pid_max; +static int zero = 0; static struct ctl_table pid_ns_ctl_table[] = { { .procname = "ns_last_pid", .maxlen = sizeof(int), .mode = 0666, /* permissions are checked in the handler */ .proc_handler = pid_ns_ctl_handler, + .extra1 = &zero, + .extra2 = &pid_max, }, { } }; diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a4ea245f3d85..649c9f876cb1 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6014,11 +6014,6 @@ static void destroy_sched_domains(struct sched_domain *sd, int cpu) * SD_SHARE_PKG_RESOURCE set (Last Level Cache Domain) for this * allows us to avoid some pointer chasing select_idle_sibling(). * - * Iterate domains and sched_groups downward, assigning CPUs to be - * select_idle_sibling() hw buddy. Cross-wiring hw makes bouncing - * due to random perturbation self canceling, ie sw buddies pull - * their counterpart to their CPU's hw counterpart. - * * Also keep a unique ID per domain (we use the first cpu number in * the cpumask of the domain), this allows us to quickly tell if * two cpus are in the same cache domain, see cpus_share_cache(). @@ -6032,40 +6027,8 @@ static void update_top_cache_domain(int cpu) int id = cpu; sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES); - if (sd) { - struct sched_domain *tmp = sd; - struct sched_group *sg, *prev; - bool right; - - /* - * Traverse to first CPU in group, and count hops - * to cpu from there, switching direction on each - * hop, never ever pointing the last CPU rightward. - */ - do { - id = cpumask_first(sched_domain_span(tmp)); - prev = sg = tmp->groups; - right = 1; - - while (cpumask_first(sched_group_cpus(sg)) != id) - sg = sg->next; - - while (!cpumask_test_cpu(cpu, sched_group_cpus(sg))) { - prev = sg; - sg = sg->next; - right = !right; - } - - /* A CPU went down, never point back to domain start. */ - if (right && cpumask_first(sched_group_cpus(sg->next)) == id) - right = false; - - sg = right ? sg->next : prev; - tmp->idle_buddy = cpumask_first(sched_group_cpus(sg)); - } while ((tmp = tmp->child)); - + if (sd) id = cpumask_first(sched_domain_span(sd)); - } rcu_assign_pointer(per_cpu(sd_llc, cpu), sd); per_cpu(sd_llc_id, cpu) = id; diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 42d9df6a5ca4..96e2b18b6283 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2637,6 +2637,8 @@ static int select_idle_sibling(struct task_struct *p, int target) int cpu = smp_processor_id(); int prev_cpu = task_cpu(p); struct sched_domain *sd; + struct sched_group *sg; + int i; /* * If the task is going to be woken-up on this cpu and if it is @@ -2653,17 +2655,29 @@ static int select_idle_sibling(struct task_struct *p, int target) return prev_cpu; /* - * Otherwise, check assigned siblings to find an elegible idle cpu. + * Otherwise, iterate the domains and find an elegible idle cpu. */ sd = rcu_dereference(per_cpu(sd_llc, target)); - for_each_lower_domain(sd) { - if (!cpumask_test_cpu(sd->idle_buddy, tsk_cpus_allowed(p))) - continue; - if (idle_cpu(sd->idle_buddy)) - return sd->idle_buddy; - } + sg = sd->groups; + do { + if (!cpumask_intersects(sched_group_cpus(sg), + tsk_cpus_allowed(p))) + goto next; + for_each_cpu(i, sched_group_cpus(sg)) { + if (!idle_cpu(i)) + goto next; + } + + target = cpumask_first_and(sched_group_cpus(sg), + tsk_cpus_allowed(p)); + goto done; +next: + sg = sg->next; + } while (sg != sd->groups); + } +done: return target; } diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 34e5eac81424..d3b91e75cecd 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -303,10 +303,11 @@ void getnstimeofday(struct timespec *ts) seq = read_seqbegin(&tk->lock); ts->tv_sec = tk->xtime_sec; - ts->tv_nsec = timekeeping_get_ns(tk); + nsecs = timekeeping_get_ns(tk); } while (read_seqretry(&tk->lock, seq)); + ts->tv_nsec = 0; timespec_add_ns(ts, nsecs); } EXPORT_SYMBOL(getnstimeofday); @@ -345,6 +346,7 @@ void ktime_get_ts(struct timespec *ts) { struct timekeeper *tk = &timekeeper; struct timespec tomono; + s64 nsec; unsigned int seq; WARN_ON(timekeeping_suspended); @@ -352,13 +354,14 @@ void ktime_get_ts(struct timespec *ts) do { seq = read_seqbegin(&tk->lock); ts->tv_sec = tk->xtime_sec; - ts->tv_nsec = timekeeping_get_ns(tk); + nsec = timekeeping_get_ns(tk); tomono = tk->wall_to_monotonic; } while (read_seqretry(&tk->lock, seq)); - set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec, - ts->tv_nsec + tomono.tv_nsec); + ts->tv_sec += tomono.tv_sec; + ts->tv_nsec = 0; + timespec_add_ns(ts, nsec + tomono.tv_nsec); } EXPORT_SYMBOL_GPL(ktime_get_ts); @@ -1244,6 +1247,7 @@ void get_monotonic_boottime(struct timespec *ts) { struct timekeeper *tk = &timekeeper; struct timespec tomono, sleep; + s64 nsec; unsigned int seq; WARN_ON(timekeeping_suspended); @@ -1251,14 +1255,15 @@ void get_monotonic_boottime(struct timespec *ts) do { seq = read_seqbegin(&tk->lock); ts->tv_sec = tk->xtime_sec; - ts->tv_nsec = timekeeping_get_ns(tk); + nsec = timekeeping_get_ns(tk); tomono = tk->wall_to_monotonic; sleep = tk->total_sleep_time; } while (read_seqretry(&tk->lock, seq)); - set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec + sleep.tv_sec, - ts->tv_nsec + tomono.tv_nsec + sleep.tv_nsec); + ts->tv_sec += tomono.tv_sec + sleep.tv_sec; + ts->tv_nsec = 0; + timespec_add_ns(ts, nsec + tomono.tv_nsec + sleep.tv_nsec); } EXPORT_SYMBOL_GPL(get_monotonic_boottime); diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 1e1373bcb3e3..3c5a79e2134c 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1349,8 +1349,16 @@ static void busy_worker_rebind_fn(struct work_struct *work) struct worker *worker = container_of(work, struct worker, rebind_work); struct global_cwq *gcwq = worker->pool->gcwq; - if (worker_maybe_bind_and_lock(worker)) - worker_clr_flags(worker, WORKER_REBIND); + worker_maybe_bind_and_lock(worker); + + /* + * %WORKER_REBIND must be cleared even if the above binding failed; + * otherwise, we may confuse the next CPU_UP cycle or oops / get + * stuck by calling idle_worker_rebind() prematurely. If CPU went + * down again inbetween, %WORKER_UNBOUND would be set, so clearing + * %WORKER_REBIND is always safe. + */ + worker_clr_flags(worker, WORKER_REBIND); spin_unlock_irq(&gcwq->lock); } @@ -3568,18 +3576,17 @@ static int __devinit workqueue_cpu_down_callback(struct notifier_block *nfb, #ifdef CONFIG_SMP struct work_for_cpu { - struct completion completion; + struct work_struct work; long (*fn)(void *); void *arg; long ret; }; -static int do_work_for_cpu(void *_wfc) +static void work_for_cpu_fn(struct work_struct *work) { - struct work_for_cpu *wfc = _wfc; + struct work_for_cpu *wfc = container_of(work, struct work_for_cpu, work); + wfc->ret = wfc->fn(wfc->arg); - complete(&wfc->completion); - return 0; } /** @@ -3594,19 +3601,11 @@ static int do_work_for_cpu(void *_wfc) */ long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg) { - struct task_struct *sub_thread; - struct work_for_cpu wfc = { - .completion = COMPLETION_INITIALIZER_ONSTACK(wfc.completion), - .fn = fn, - .arg = arg, - }; + struct work_for_cpu wfc = { .fn = fn, .arg = arg }; - sub_thread = kthread_create(do_work_for_cpu, &wfc, "work_for_cpu"); - if (IS_ERR(sub_thread)) - return PTR_ERR(sub_thread); - kthread_bind(sub_thread, cpu); - wake_up_process(sub_thread); - wait_for_completion(&wfc.completion); + INIT_WORK_ONSTACK(&wfc.work, work_for_cpu_fn); + schedule_work_on(cpu, &wfc.work); + flush_work(&wfc.work); return wfc.ret; } EXPORT_SYMBOL_GPL(work_on_cpu); |