diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/events/core.c | 91 | ||||
-rw-r--r-- | kernel/events/internal.h | 3 | ||||
-rw-r--r-- | kernel/events/ring_buffer.c | 3 | ||||
-rw-r--r-- | kernel/irq/manage.c | 5 | ||||
-rw-r--r-- | kernel/jump_label.c | 3 | ||||
-rw-r--r-- | kernel/printk.c | 3 | ||||
-rw-r--r-- | kernel/sched.c | 17 | ||||
-rw-r--r-- | kernel/sched_fair.c | 159 | ||||
-rw-r--r-- | kernel/sched_features.h | 1 | ||||
-rw-r--r-- | kernel/sched_rt.c | 3 | ||||
-rw-r--r-- | kernel/time/alarmtimer.c | 2 | ||||
-rw-r--r-- | kernel/time/clockevents.c | 1 | ||||
-rw-r--r-- | kernel/time/clocksource.c | 4 | ||||
-rw-r--r-- | kernel/time/tick-broadcast.c | 2 | ||||
-rw-r--r-- | kernel/timer.c | 2 | ||||
-rw-r--r-- | kernel/trace/ftrace.c | 5 | ||||
-rw-r--r-- | kernel/trace/trace_events.c | 1 | ||||
-rw-r--r-- | kernel/trace/trace_events_filter.c | 13 |
18 files changed, 265 insertions, 53 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index 0e8457d..d3b9df5 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -185,6 +185,9 @@ static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, static void update_context_time(struct perf_event_context *ctx); static u64 perf_event_time(struct perf_event *event); +static void ring_buffer_attach(struct perf_event *event, + struct ring_buffer *rb); + void __weak perf_event_print_debug(void) { } extern __weak const char *perf_pmu_name(void) @@ -2171,9 +2174,10 @@ static void perf_event_context_sched_in(struct perf_event_context *ctx, */ cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); - perf_event_sched_in(cpuctx, ctx, task); + if (ctx->nr_events) + cpuctx->task_ctx = ctx; - cpuctx->task_ctx = ctx; + perf_event_sched_in(cpuctx, cpuctx->task_ctx, task); perf_pmu_enable(ctx->pmu); perf_ctx_unlock(cpuctx, ctx); @@ -3190,12 +3194,33 @@ static unsigned int perf_poll(struct file *file, poll_table *wait) struct ring_buffer *rb; unsigned int events = POLL_HUP; + /* + * Race between perf_event_set_output() and perf_poll(): perf_poll() + * grabs the rb reference but perf_event_set_output() overrides it. + * Here is the timeline for two threads T1, T2: + * t0: T1, rb = rcu_dereference(event->rb) + * t1: T2, old_rb = event->rb + * t2: T2, event->rb = new rb + * t3: T2, ring_buffer_detach(old_rb) + * t4: T1, ring_buffer_attach(rb1) + * t5: T1, poll_wait(event->waitq) + * + * To avoid this problem, we grab mmap_mutex in perf_poll() + * thereby ensuring that the assignment of the new ring buffer + * and the detachment of the old buffer appear atomic to perf_poll() + */ + mutex_lock(&event->mmap_mutex); + rcu_read_lock(); rb = rcu_dereference(event->rb); - if (rb) + if (rb) { + ring_buffer_attach(event, rb); events = atomic_xchg(&rb->poll, 0); + } rcu_read_unlock(); + mutex_unlock(&event->mmap_mutex); + poll_wait(file, &event->waitq, wait); return events; @@ -3496,6 +3521,49 @@ unlock: return ret; } +static void ring_buffer_attach(struct perf_event *event, + struct ring_buffer *rb) +{ + unsigned long flags; + + if (!list_empty(&event->rb_entry)) + return; + + spin_lock_irqsave(&rb->event_lock, flags); + if (!list_empty(&event->rb_entry)) + goto unlock; + + list_add(&event->rb_entry, &rb->event_list); +unlock: + spin_unlock_irqrestore(&rb->event_lock, flags); +} + +static void ring_buffer_detach(struct perf_event *event, + struct ring_buffer *rb) +{ + unsigned long flags; + + if (list_empty(&event->rb_entry)) + return; + + spin_lock_irqsave(&rb->event_lock, flags); + list_del_init(&event->rb_entry); + wake_up_all(&event->waitq); + spin_unlock_irqrestore(&rb->event_lock, flags); +} + +static void ring_buffer_wakeup(struct perf_event *event) +{ + struct ring_buffer *rb; + + rcu_read_lock(); + rb = rcu_dereference(event->rb); + list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { + wake_up_all(&event->waitq); + } + rcu_read_unlock(); +} + static void rb_free_rcu(struct rcu_head *rcu_head) { struct ring_buffer *rb; @@ -3521,9 +3589,19 @@ static struct ring_buffer *ring_buffer_get(struct perf_event *event) static void ring_buffer_put(struct ring_buffer *rb) { + struct perf_event *event, *n; + unsigned long flags; + if (!atomic_dec_and_test(&rb->refcount)) return; + spin_lock_irqsave(&rb->event_lock, flags); + list_for_each_entry_safe(event, n, &rb->event_list, rb_entry) { + list_del_init(&event->rb_entry); + wake_up_all(&event->waitq); + } + spin_unlock_irqrestore(&rb->event_lock, flags); + call_rcu(&rb->rcu_head, rb_free_rcu); } @@ -3546,6 +3624,7 @@ static void perf_mmap_close(struct vm_area_struct *vma) atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm); vma->vm_mm->pinned_vm -= event->mmap_locked; rcu_assign_pointer(event->rb, NULL); + ring_buffer_detach(event, rb); mutex_unlock(&event->mmap_mutex); ring_buffer_put(rb); @@ -3700,7 +3779,7 @@ static const struct file_operations perf_fops = { void perf_event_wakeup(struct perf_event *event) { - wake_up_all(&event->waitq); + ring_buffer_wakeup(event); if (event->pending_kill) { kill_fasync(&event->fasync, SIGIO, event->pending_kill); @@ -5822,6 +5901,8 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, INIT_LIST_HEAD(&event->group_entry); INIT_LIST_HEAD(&event->event_entry); INIT_LIST_HEAD(&event->sibling_list); + INIT_LIST_HEAD(&event->rb_entry); + init_waitqueue_head(&event->waitq); init_irq_work(&event->pending, perf_pending_event); @@ -6028,6 +6109,8 @@ set: old_rb = event->rb; rcu_assign_pointer(event->rb, rb); + if (old_rb) + ring_buffer_detach(event, old_rb); ret = 0; unlock: mutex_unlock(&event->mmap_mutex); diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 09097dd..64568a6 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -22,6 +22,9 @@ struct ring_buffer { local_t lost; /* nr records lost */ long watermark; /* wakeup watermark */ + /* poll crap */ + spinlock_t event_lock; + struct list_head event_list; struct perf_event_mmap_page *user_page; void *data_pages[0]; diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index a2a2920..7f3011c 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -209,6 +209,9 @@ ring_buffer_init(struct ring_buffer *rb, long watermark, int flags) rb->writable = 1; atomic_set(&rb->refcount, 1); + + INIT_LIST_HEAD(&rb->event_list); + spin_lock_init(&rb->event_lock); } #ifndef CONFIG_PERF_USE_VMALLOC diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 0e2b179..1da999f 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -623,8 +623,9 @@ static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id) static int irq_wait_for_interrupt(struct irqaction *action) { + set_current_state(TASK_INTERRUPTIBLE); + while (!kthread_should_stop()) { - set_current_state(TASK_INTERRUPTIBLE); if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags)) { @@ -632,7 +633,9 @@ static int irq_wait_for_interrupt(struct irqaction *action) return 0; } schedule(); + set_current_state(TASK_INTERRUPTIBLE); } + __set_current_state(TASK_RUNNING); return -1; } diff --git a/kernel/jump_label.c b/kernel/jump_label.c index bbdfe2a..66ff710 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -66,8 +66,9 @@ void jump_label_inc(struct jump_label_key *key) return; jump_label_lock(); - if (atomic_add_return(1, &key->enabled) == 1) + if (atomic_read(&key->enabled) == 0) jump_label_update(key, JUMP_LABEL_ENABLE); + atomic_inc(&key->enabled); jump_label_unlock(); } diff --git a/kernel/printk.c b/kernel/printk.c index 1455a0d..7982a0a 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -1293,10 +1293,11 @@ again: raw_spin_lock(&logbuf_lock); if (con_start != log_end) retry = 1; + raw_spin_unlock_irqrestore(&logbuf_lock, flags); + if (retry && console_trylock()) goto again; - raw_spin_unlock_irqrestore(&logbuf_lock, flags); if (wake_klogd) wake_up_klogd(); } diff --git a/kernel/sched.c b/kernel/sched.c index 0e9344a..d6b149c 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -71,6 +71,7 @@ #include <linux/ctype.h> #include <linux/ftrace.h> #include <linux/slab.h> +#include <linux/init_task.h> #include <asm/tlb.h> #include <asm/irq_regs.h> @@ -4810,6 +4811,9 @@ EXPORT_SYMBOL(wait_for_completion); * This waits for either a completion of a specific task to be signaled or for a * specified timeout to expire. The timeout is in jiffies. It is not * interruptible. + * + * The return value is 0 if timed out, and positive (at least 1, or number of + * jiffies left till timeout) if completed. */ unsigned long __sched wait_for_completion_timeout(struct completion *x, unsigned long timeout) @@ -4824,6 +4828,8 @@ EXPORT_SYMBOL(wait_for_completion_timeout); * * This waits for completion of a specific task to be signaled. It is * interruptible. + * + * The return value is -ERESTARTSYS if interrupted, 0 if completed. */ int __sched wait_for_completion_interruptible(struct completion *x) { @@ -4841,6 +4847,9 @@ EXPORT_SYMBOL(wait_for_completion_interruptible); * * This waits for either a completion of a specific task to be signaled or for a * specified timeout to expire. It is interruptible. The timeout is in jiffies. + * + * The return value is -ERESTARTSYS if interrupted, 0 if timed out, + * positive (at least 1, or number of jiffies left till timeout) if completed. */ long __sched wait_for_completion_interruptible_timeout(struct completion *x, @@ -4856,6 +4865,8 @@ EXPORT_SYMBOL(wait_for_completion_interruptible_timeout); * * This waits to be signaled for completion of a specific task. It can be * interrupted by a kill signal. + * + * The return value is -ERESTARTSYS if interrupted, 0 if completed. */ int __sched wait_for_completion_killable(struct completion *x) { @@ -4874,6 +4885,9 @@ EXPORT_SYMBOL(wait_for_completion_killable); * This waits for either a completion of a specific task to be * signaled or for a specified timeout to expire. It can be * interrupted by a kill signal. The timeout is in jiffies. + * + * The return value is -ERESTARTSYS if interrupted, 0 if timed out, + * positive (at least 1, or number of jiffies left till timeout) if completed. */ long __sched wait_for_completion_killable_timeout(struct completion *x, @@ -6099,6 +6113,9 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) */ idle->sched_class = &idle_sched_class; ftrace_graph_init_idle_task(idle, cpu); +#if defined(CONFIG_SMP) + sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu); +#endif } /* diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 5c9e679..a78ed27 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -772,19 +772,32 @@ static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update) list_del_leaf_cfs_rq(cfs_rq); } +static inline long calc_tg_weight(struct task_group *tg, struct cfs_rq *cfs_rq) +{ + long tg_weight; + + /* + * Use this CPU's actual weight instead of the last load_contribution + * to gain a more accurate current total weight. See + * update_cfs_rq_load_contribution(). + */ + tg_weight = atomic_read(&tg->load_weight); + tg_weight -= cfs_rq->load_contribution; + tg_weight += cfs_rq->load.weight; + + return tg_weight; +} + static long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg) { - long load_weight, load, shares; + long tg_weight, load, shares; + tg_weight = calc_tg_weight(tg, cfs_rq); load = cfs_rq->load.weight; - load_weight = atomic_read(&tg->load_weight); - load_weight += load; - load_weight -= cfs_rq->load_contribution; - shares = (tg->shares * load); - if (load_weight) - shares /= load_weight; + if (tg_weight) + shares /= tg_weight; if (shares < MIN_SHARES) shares = MIN_SHARES; @@ -1743,7 +1756,7 @@ static void __return_cfs_rq_runtime(struct cfs_rq *cfs_rq) static __always_inline void return_cfs_rq_runtime(struct cfs_rq *cfs_rq) { - if (!cfs_rq->runtime_enabled || !cfs_rq->nr_running) + if (!cfs_rq->runtime_enabled || cfs_rq->nr_running) return; __return_cfs_rq_runtime(cfs_rq); @@ -2036,36 +2049,100 @@ static void task_waking_fair(struct task_struct *p) * Adding load to a group doesn't make a group heavier, but can cause movement * of group shares between cpus. Assuming the shares were perfectly aligned one * can calculate the shift in shares. + * + * Calculate the effective load difference if @wl is added (subtracted) to @tg + * on this @cpu and results in a total addition (subtraction) of @wg to the + * total group weight. + * + * Given a runqueue weight distribution (rw_i) we can compute a shares + * distribution (s_i) using: + * + * s_i = rw_i / \Sum rw_j (1) + * + * Suppose we have 4 CPUs and our @tg is a direct child of the root group and + * has 7 equal weight tasks, distributed as below (rw_i), with the resulting + * shares distribution (s_i): + * + * rw_i = { 2, 4, 1, 0 } + * s_i = { 2/7, 4/7, 1/7, 0 } + * + * As per wake_affine() we're interested in the load of two CPUs (the CPU the + * task used to run on and the CPU the waker is running on), we need to + * compute the effect of waking a task on either CPU and, in case of a sync + * wakeup, compute the effect of the current task going to sleep. + * + * So for a change of @wl to the local @cpu with an overall group weight change + * of @wl we can compute the new shares distribution (s'_i) using: + * + * s'_i = (rw_i + @wl) / (@wg + \Sum rw_j) (2) + * + * Suppose we're interested in CPUs 0 and 1, and want to compute the load + * differences in waking a task to CPU 0. The additional task changes the + * weight and shares distributions like: + * + * rw'_i = { 3, 4, 1, 0 } + * s'_i = { 3/8, 4/8, 1/8, 0 } + * + * We can then compute the difference in effective weight by using: + * + * dw_i = S * (s'_i - s_i) (3) + * + * Where 'S' is the group weight as seen by its parent. + * + * Therefore the effective change in loads on CPU 0 would be 5/56 (3/8 - 2/7) + * times the weight of the group. The effect on CPU 1 would be -4/56 (4/8 - + * 4/7) times the weight of the group. */ static long effective_load(struct task_group *tg, int cpu, long wl, long wg) { struct sched_entity *se = tg->se[cpu]; - if (!tg->parent) + if (!tg->parent) /* the trivial, non-cgroup case */ return wl; for_each_sched_entity(se) { - long lw, w; + long w, W; tg = se->my_q->tg; - w = se->my_q->load.weight; - /* use this cpu's instantaneous contribution */ - lw = atomic_read(&tg->load_weight); - lw -= se->my_q->load_contribution; - lw += w + wg; + /* + * W = @wg + \Sum rw_j + */ + W = wg + calc_tg_weight(tg, se->my_q); - wl += w; + /* + * w = rw_i + @wl + */ + w = se->my_q->load.weight + wl; - if (lw > 0 && wl < lw) - wl = (wl * tg->shares) / lw; + /* + * wl = S * s'_i; see (2) + */ + if (W > 0 && w < W) + wl = (w * tg->shares) / W; else wl = tg->shares; - /* zero point is MIN_SHARES */ + /* + * Per the above, wl is the new se->load.weight value; since + * those are clipped to [MIN_SHARES, ...) do so now. See + * calc_cfs_shares(). + */ if (wl < MIN_SHARES) wl = MIN_SHARES; + + /* + * wl = dw_i = S * (s'_i - s_i); see (3) + */ wl -= se->load.weight; + + /* + * Recursively apply this logic to all parent groups to compute + * the final effective load change on the root group. Since + * only the @tg group gets extra weight, all parent groups can + * only redistribute existing shares. @wl is the shift in shares + * resulting from this level per the above. + */ wg = 0; } @@ -2249,7 +2326,8 @@ 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; - int i; + struct sched_group *sg; + int i, smt = 0; /* * If the task is going to be woken-up on this cpu and if it is @@ -2269,25 +2347,38 @@ static int select_idle_sibling(struct task_struct *p, int target) * Otherwise, iterate the domains and find an elegible idle cpu. */ rcu_read_lock(); +again: for_each_domain(target, sd) { - if (!(sd->flags & SD_SHARE_PKG_RESOURCES)) - break; + if (!smt && (sd->flags & SD_SHARE_CPUPOWER)) + continue; - for_each_cpu_and(i, sched_domain_span(sd), tsk_cpus_allowed(p)) { - if (idle_cpu(i)) { - target = i; - break; + if (!(sd->flags & SD_SHARE_PKG_RESOURCES)) { + if (!smt) { + smt = 1; + goto again; } + break; } - /* - * Lets stop looking for an idle sibling when we reached - * the domain that spans the current cpu and prev_cpu. - */ - if (cpumask_test_cpu(cpu, sched_domain_span(sd)) && - cpumask_test_cpu(prev_cpu, sched_domain_span(sd))) - break; + 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: rcu_read_unlock(); return target; @@ -3511,7 +3602,7 @@ static bool update_sd_pick_busiest(struct sched_domain *sd, } /** - * update_sd_lb_stats - Update sched_group's statistics for load balancing. + * update_sd_lb_stats - Update sched_domain's statistics for load balancing. * @sd: sched_domain whose statistics are to be updated. * @this_cpu: Cpu for which load balance is currently performed. * @idle: Idle status of this_cpu diff --git a/kernel/sched_features.h b/kernel/sched_features.h index efa0a7b..8480224 100644 --- a/kernel/sched_features.h +++ b/kernel/sched_features.h @@ -67,3 +67,4 @@ SCHED_FEAT(NONTASK_POWER, 1) SCHED_FEAT(TTWU_QUEUE, 1) SCHED_FEAT(FORCE_SD_OVERLAP, 0) +SCHED_FEAT(RT_RUNTIME_SHARE, 1) diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 056cbd2..583a136 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -560,6 +560,9 @@ static int balance_runtime(struct rt_rq *rt_rq) { int more = 0; + if (!sched_feat(RT_RUNTIME_SHARE)) + return more; + if (rt_rq->rt_time > rt_rq->rt_runtime) { raw_spin_unlock(&rt_rq->rt_runtime_lock); more = do_balance_runtime(rt_rq); diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index c436e79..8a46f5d 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -195,7 +195,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) struct alarm *alarm; ktime_t expired = next->expires; - if (expired.tv64 >= now.tv64) + if (expired.tv64 > now.tv64) break; alarm = container_of(next, struct alarm, node); diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 1ecd6ba..c4eb71c 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -387,6 +387,7 @@ void clockevents_exchange_device(struct clock_event_device *old, * released list and do a notify add later. */ if (old) { + old->event_handler = clockevents_handle_noop; clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED); list_del(&old->list); list_add(&old->list, &clockevents_released); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index cfc65e1..da2f760 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -548,7 +548,7 @@ static u64 clocksource_max_deferment(struct clocksource *cs) * note a margin of 12.5% is used because this can be computed with * a shift, versus say 10% which would require division. */ - return max_nsecs - (max_nsecs >> 5); + return max_nsecs - (max_nsecs >> 3); } #ifndef CONFIG_ARCH_USES_GETTIMEOFFSET @@ -669,7 +669,7 @@ void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq) * ~ 0.06ppm granularity for NTP. We apply the same 12.5% * margin as we do in clocksource_max_deferment() */ - sec = (cs->mask - (cs->mask >> 5)); + sec = (cs->mask - (cs->mask >> 3)); do_div(sec, freq); do_div(sec, scale); if (!sec) diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index f954282..fd4a7b1 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -71,7 +71,7 @@ int tick_check_broadcast_device(struct clock_event_device *dev) (dev->features & CLOCK_EVT_FEAT_C3STOP)) return 0; - clockevents_exchange_device(NULL, dev); + clockevents_exchange_device(tick_broadcast_device.evtdev, dev); tick_broadcast_device.evtdev = dev; if (!cpumask_empty(tick_get_broadcast_mask())) tick_broadcast_start_periodic(dev); diff --git a/kernel/timer.c b/kernel/timer.c index dbaa624..9c3c62b 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -1368,7 +1368,7 @@ SYSCALL_DEFINE0(getppid) int pid; rcu_read_lock(); - pid = task_tgid_vnr(current->real_parent); + pid = task_tgid_vnr(rcu_dereference(current->real_parent)); rcu_read_unlock(); return pid; diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 900b409..b1e8943 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -152,7 +152,6 @@ void clear_ftrace_function(void) ftrace_pid_function = ftrace_stub; } -#undef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST /* * For those archs that do not test ftrace_trace_stop in their @@ -1212,7 +1211,9 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable, if (!src->count) { free_ftrace_hash_rcu(*dst); rcu_assign_pointer(*dst, EMPTY_HASH); - return 0; + /* still need to update the function records */ + ret = 0; + goto out; } /* diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 581876f..c212a7f 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1078,7 +1078,6 @@ event_subsystem_dir(const char *name, struct dentry *d_events) /* First see if we did not already create this dir */ list_for_each_entry(system, &event_subsystems, list) { if (strcmp(system->name, name) == 0) { - __get_system(system); system->nr_events++; return system->entry; } diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 816d3d0..95dc31e 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -1649,7 +1649,9 @@ static int replace_system_preds(struct event_subsystem *system, */ err = replace_preds(call, NULL, ps, filter_string, true); if (err) - goto fail; + call->flags |= TRACE_EVENT_FL_NO_SET_FILTER; + else + call->flags &= ~TRACE_EVENT_FL_NO_SET_FILTER; } list_for_each_entry(call, &ftrace_events, list) { @@ -1658,6 +1660,9 @@ static int replace_system_preds(struct event_subsystem *system, if (strcmp(call->class->system, system->name) != 0) continue; + if (call->flags & TRACE_EVENT_FL_NO_SET_FILTER) + continue; + filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL); if (!filter_item) goto fail_mem; @@ -1686,7 +1691,7 @@ static int replace_system_preds(struct event_subsystem *system, * replace the filter for the call. */ filter = call->filter; - call->filter = filter_item->filter; + rcu_assign_pointer(call->filter, filter_item->filter); filter_item->filter = filter; fail = false; @@ -1741,7 +1746,7 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string) filter = call->filter; if (!filter) goto out_unlock; - call->filter = NULL; + RCU_INIT_POINTER(call->filter, NULL); /* Make sure the filter is not being used */ synchronize_sched(); __free_filter(filter); @@ -1782,7 +1787,7 @@ out: * string */ tmp = call->filter; - call->filter = filter; + rcu_assign_pointer(call->filter, filter); if (tmp) { /* Make sure the call is done with the filter */ synchronize_sched(); |