X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Fperf_event.c;h=e0eb4a2fe1833e9de3b5ff10f6959358d31e2806;hb=a121f24accac1600bf5b6fb1e12eeabdfed7cb1a;hp=34a1b9d7633e83aee544335f09185c3658db1564;hpb=c6567f642e20bcc79abed030f44be5b0d6da2ded;p=safe%2Fjmp%2Flinux-2.6 diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 34a1b9d..e0eb4a2 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -36,7 +36,7 @@ /* * Each CPU has a list of per CPU events: */ -DEFINE_PER_CPU(struct perf_cpu_context, perf_cpu_context); +static DEFINE_PER_CPU(struct perf_cpu_context, perf_cpu_context); int perf_max_events __read_mostly = 1; static int perf_reserved_percpu __read_mostly; @@ -203,14 +203,14 @@ perf_lock_task_context(struct task_struct *task, unsigned long *flags) * if so. If we locked the right context, then it * can't get swapped on us any more. */ - spin_lock_irqsave(&ctx->lock, *flags); + raw_spin_lock_irqsave(&ctx->lock, *flags); if (ctx != rcu_dereference(task->perf_event_ctxp)) { - spin_unlock_irqrestore(&ctx->lock, *flags); + raw_spin_unlock_irqrestore(&ctx->lock, *flags); goto retry; } if (!atomic_inc_not_zero(&ctx->refcount)) { - spin_unlock_irqrestore(&ctx->lock, *flags); + raw_spin_unlock_irqrestore(&ctx->lock, *flags); ctx = NULL; } } @@ -231,7 +231,7 @@ static struct perf_event_context *perf_pin_task_context(struct task_struct *task ctx = perf_lock_task_context(task, &flags); if (ctx) { ++ctx->pin_count; - spin_unlock_irqrestore(&ctx->lock, flags); + raw_spin_unlock_irqrestore(&ctx->lock, flags); } return ctx; } @@ -240,9 +240,9 @@ static void perf_unpin_context(struct perf_event_context *ctx) { unsigned long flags; - spin_lock_irqsave(&ctx->lock, flags); + raw_spin_lock_irqsave(&ctx->lock, flags); --ctx->pin_count; - spin_unlock_irqrestore(&ctx->lock, flags); + raw_spin_unlock_irqrestore(&ctx->lock, flags); put_ctx(ctx); } @@ -338,7 +338,16 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx) event->group_leader->nr_siblings--; update_event_times(event); - event->state = PERF_EVENT_STATE_OFF; + + /* + * If event was in error state, then keep it + * that way, otherwise bogus counts will be + * returned on read(). The only way to get out + * of error state is by explicit re-enabling + * of the event + */ + if (event->state > PERF_EVENT_STATE_OFF) + event->state = PERF_EVENT_STATE_OFF; /* * If this was a group event with sibling events then @@ -418,7 +427,7 @@ static void __perf_event_remove_from_context(void *info) if (ctx->task && cpuctx->task_ctx != ctx) return; - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); /* * Protect the list operation against NMI by disabling the * events on a global level. @@ -440,7 +449,7 @@ static void __perf_event_remove_from_context(void *info) } perf_enable(); - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); } @@ -467,7 +476,7 @@ static void perf_event_remove_from_context(struct perf_event *event) if (!task) { /* * Per cpu events are removed via an smp call and - * the removal is always sucessful. + * the removal is always successful. */ smp_call_function_single(event->cpu, __perf_event_remove_from_context, @@ -479,12 +488,12 @@ retry: task_oncpu_function_call(task, __perf_event_remove_from_context, event); - spin_lock_irq(&ctx->lock); + raw_spin_lock_irq(&ctx->lock); /* * If the context is active we need to retry the smp call. */ if (ctx->nr_active && !list_empty(&event->group_entry)) { - spin_unlock_irq(&ctx->lock); + raw_spin_unlock_irq(&ctx->lock); goto retry; } @@ -495,7 +504,7 @@ retry: */ if (!list_empty(&event->group_entry)) list_del_event(event, ctx); - spin_unlock_irq(&ctx->lock); + raw_spin_unlock_irq(&ctx->lock); } /* @@ -526,7 +535,7 @@ static void __perf_event_disable(void *info) if (ctx->task && cpuctx->task_ctx != ctx) return; - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); /* * If the event is on, turn it off. @@ -542,7 +551,7 @@ static void __perf_event_disable(void *info) event->state = PERF_EVENT_STATE_OFF; } - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); } /* @@ -558,7 +567,7 @@ static void __perf_event_disable(void *info) * is the current context on this CPU and preemption is disabled, * hence we can't get into perf_event_task_sched_out for this context. */ -static void perf_event_disable(struct perf_event *event) +void perf_event_disable(struct perf_event *event) { struct perf_event_context *ctx = event->ctx; struct task_struct *task = ctx->task; @@ -575,12 +584,12 @@ static void perf_event_disable(struct perf_event *event) retry: task_oncpu_function_call(task, __perf_event_disable, event); - spin_lock_irq(&ctx->lock); + raw_spin_lock_irq(&ctx->lock); /* * If the event is still active, we need to retry the cross-call. */ if (event->state == PERF_EVENT_STATE_ACTIVE) { - spin_unlock_irq(&ctx->lock); + raw_spin_unlock_irq(&ctx->lock); goto retry; } @@ -593,7 +602,7 @@ static void perf_event_disable(struct perf_event *event) event->state = PERF_EVENT_STATE_OFF; } - spin_unlock_irq(&ctx->lock); + raw_spin_unlock_irq(&ctx->lock); } static int @@ -761,7 +770,7 @@ static void __perf_install_in_context(void *info) cpuctx->task_ctx = ctx; } - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); ctx->is_active = 1; update_context_time(ctx); @@ -773,6 +782,9 @@ static void __perf_install_in_context(void *info) add_event_to_ctx(event, ctx); + if (event->cpu != -1 && event->cpu != smp_processor_id()) + goto unlock; + /* * Don't put the event on if it is disabled or if * it is in a group and the group isn't on. @@ -811,7 +823,7 @@ static void __perf_install_in_context(void *info) unlock: perf_enable(); - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); } /* @@ -836,7 +848,7 @@ perf_install_in_context(struct perf_event_context *ctx, if (!task) { /* * Per cpu events are installed via an smp call and - * the install is always sucessful. + * the install is always successful. */ smp_call_function_single(cpu, __perf_install_in_context, event, 1); @@ -847,12 +859,12 @@ retry: task_oncpu_function_call(task, __perf_install_in_context, event); - spin_lock_irq(&ctx->lock); + raw_spin_lock_irq(&ctx->lock); /* * we need to retry the smp call. */ if (ctx->is_active && list_empty(&event->group_entry)) { - spin_unlock_irq(&ctx->lock); + raw_spin_unlock_irq(&ctx->lock); goto retry; } @@ -863,7 +875,7 @@ retry: */ if (list_empty(&event->group_entry)) add_event_to_ctx(event, ctx); - spin_unlock_irq(&ctx->lock); + raw_spin_unlock_irq(&ctx->lock); } /* @@ -908,7 +920,7 @@ static void __perf_event_enable(void *info) cpuctx->task_ctx = ctx; } - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); ctx->is_active = 1; update_context_time(ctx); @@ -916,6 +928,9 @@ static void __perf_event_enable(void *info) goto unlock; __perf_event_mark_enabled(event, ctx); + if (event->cpu != -1 && event->cpu != smp_processor_id()) + goto unlock; + /* * If the event is in a group and isn't the group leader, * then don't put it on unless the group is on. @@ -950,7 +965,7 @@ static void __perf_event_enable(void *info) } unlock: - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); } /* @@ -962,7 +977,7 @@ static void __perf_event_enable(void *info) * perf_event_for_each_child or perf_event_for_each as described * for perf_event_disable. */ -static void perf_event_enable(struct perf_event *event) +void perf_event_enable(struct perf_event *event) { struct perf_event_context *ctx = event->ctx; struct task_struct *task = ctx->task; @@ -976,7 +991,7 @@ static void perf_event_enable(struct perf_event *event) return; } - spin_lock_irq(&ctx->lock); + raw_spin_lock_irq(&ctx->lock); if (event->state >= PERF_EVENT_STATE_INACTIVE) goto out; @@ -991,10 +1006,10 @@ static void perf_event_enable(struct perf_event *event) event->state = PERF_EVENT_STATE_OFF; retry: - spin_unlock_irq(&ctx->lock); + raw_spin_unlock_irq(&ctx->lock); task_oncpu_function_call(task, __perf_event_enable, event); - spin_lock_irq(&ctx->lock); + raw_spin_lock_irq(&ctx->lock); /* * If the context is active and the event is still off, @@ -1011,7 +1026,7 @@ static void perf_event_enable(struct perf_event *event) __perf_event_mark_enabled(event, ctx); out: - spin_unlock_irq(&ctx->lock); + raw_spin_unlock_irq(&ctx->lock); } static int perf_event_refresh(struct perf_event *event, int refresh) @@ -1033,7 +1048,7 @@ void __perf_event_sched_out(struct perf_event_context *ctx, { struct perf_event *event; - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); ctx->is_active = 0; if (likely(!ctx->nr_events)) goto out; @@ -1046,7 +1061,7 @@ void __perf_event_sched_out(struct perf_event_context *ctx, } perf_enable(); out: - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); } /* @@ -1184,8 +1199,8 @@ void perf_event_task_sched_out(struct task_struct *task, * order we take the locks because no other cpu could * be trying to lock both of these tasks. */ - spin_lock(&ctx->lock); - spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); + raw_spin_lock(&ctx->lock); + raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); if (context_equiv(ctx, next_ctx)) { /* * XXX do we need a memory barrier of sorts @@ -1199,8 +1214,8 @@ void perf_event_task_sched_out(struct task_struct *task, perf_event_sync_stat(ctx, next_ctx); } - spin_unlock(&next_ctx->lock); - spin_unlock(&ctx->lock); + raw_spin_unlock(&next_ctx->lock); + raw_spin_unlock(&ctx->lock); } rcu_read_unlock(); @@ -1242,7 +1257,7 @@ __perf_event_sched_in(struct perf_event_context *ctx, struct perf_event *event; int can_add_hw = 1; - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); ctx->is_active = 1; if (likely(!ctx->nr_events)) goto out; @@ -1297,7 +1312,7 @@ __perf_event_sched_in(struct perf_event_context *ctx, } perf_enable(); out: - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); } /* @@ -1361,11 +1376,14 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx) struct hw_perf_event *hwc; u64 interrupts, freq; - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { if (event->state != PERF_EVENT_STATE_ACTIVE) continue; + if (event->cpu != -1 && event->cpu != smp_processor_id()) + continue; + hwc = &event->hw; interrupts = hwc->interrupts; @@ -1416,7 +1434,7 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx) perf_enable(); } } - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); } /* @@ -1429,7 +1447,7 @@ static void rotate_ctx(struct perf_event_context *ctx) if (!ctx->nr_events) return; - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); /* * Rotate the first entry last (works just fine for group events too): */ @@ -1440,7 +1458,7 @@ static void rotate_ctx(struct perf_event_context *ctx) } perf_enable(); - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); } void perf_event_task_tick(struct task_struct *curr, int cpu) @@ -1489,7 +1507,7 @@ static void perf_event_enable_on_exec(struct task_struct *task) __perf_event_task_sched_out(ctx); - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); list_for_each_entry(event, &ctx->group_list, group_entry) { if (!event->attr.enable_on_exec) @@ -1507,7 +1525,7 @@ static void perf_event_enable_on_exec(struct task_struct *task) if (enabled) unclone_ctx(ctx); - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); perf_event_task_sched_in(task, smp_processor_id()); out: @@ -1533,10 +1551,10 @@ static void __perf_event_read(void *info) if (ctx->task && cpuctx->task_ctx != ctx) return; - spin_lock(&ctx->lock); + raw_spin_lock(&ctx->lock); update_context_time(ctx); update_event_times(event); - spin_unlock(&ctx->lock); + raw_spin_unlock(&ctx->lock); event->pmu->read(event); } @@ -1554,10 +1572,10 @@ static u64 perf_event_read(struct perf_event *event) struct perf_event_context *ctx = event->ctx; unsigned long flags; - spin_lock_irqsave(&ctx->lock, flags); + raw_spin_lock_irqsave(&ctx->lock, flags); update_context_time(ctx); update_event_times(event); - spin_unlock_irqrestore(&ctx->lock, flags); + raw_spin_unlock_irqrestore(&ctx->lock, flags); } return atomic64_read(&event->count); @@ -1570,8 +1588,7 @@ static void __perf_event_init_context(struct perf_event_context *ctx, struct task_struct *task) { - memset(ctx, 0, sizeof(*ctx)); - spin_lock_init(&ctx->lock); + raw_spin_lock_init(&ctx->lock); mutex_init(&ctx->mutex); INIT_LIST_HEAD(&ctx->group_list); INIT_LIST_HEAD(&ctx->event_list); @@ -1587,15 +1604,12 @@ static struct perf_event_context *find_get_context(pid_t pid, int cpu) unsigned long flags; int err; - /* - * If cpu is not a wildcard then this is a percpu event: - */ - if (cpu != -1) { + if (pid == -1 && cpu != -1) { /* Must be root to operate on a CPU event: */ if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) return ERR_PTR(-EACCES); - if (cpu < 0 || cpu > num_possible_cpus()) + if (cpu < 0 || cpu >= nr_cpumask_bits) return ERR_PTR(-EINVAL); /* @@ -1603,7 +1617,7 @@ static struct perf_event_context *find_get_context(pid_t pid, int cpu) * offline CPU and activate it when the CPU comes up, but * that's for later. */ - if (!cpu_isset(cpu, cpu_online_map)) + if (!cpu_online(cpu)) return ERR_PTR(-ENODEV); cpuctx = &per_cpu(perf_cpu_context, cpu); @@ -1641,11 +1655,11 @@ static struct perf_event_context *find_get_context(pid_t pid, int cpu) ctx = perf_lock_task_context(task, &flags); if (ctx) { unclone_ctx(ctx); - spin_unlock_irqrestore(&ctx->lock, flags); + raw_spin_unlock_irqrestore(&ctx->lock, flags); } if (!ctx) { - ctx = kmalloc(sizeof(struct perf_event_context), GFP_KERNEL); + ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); err = -ENOMEM; if (!ctx) goto errout; @@ -1979,7 +1993,7 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg) if (!value) return -EINVAL; - spin_lock_irq(&ctx->lock); + raw_spin_lock_irq(&ctx->lock); if (event->attr.freq) { if (value > sysctl_perf_event_sample_rate) { ret = -EINVAL; @@ -1992,7 +2006,7 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg) event->hw.sample_period = value; } unlock: - spin_unlock_irq(&ctx->lock); + raw_spin_unlock_irq(&ctx->lock); return ret; } @@ -2201,6 +2215,7 @@ static void perf_mmap_data_free(struct perf_mmap_data *data) perf_mmap_free_page((unsigned long)data->user_page); for (i = 0; i < data->nr_pages; i++) perf_mmap_free_page((unsigned long)data->data_pages[i]); + kfree(data); } #else @@ -2241,6 +2256,7 @@ static void perf_mmap_data_free_work(struct work_struct *work) perf_mmap_unmark_page(base + (i * PAGE_SIZE)); vfree(base); + kfree(data); } static void perf_mmap_data_free(struct perf_mmap_data *data) @@ -2346,7 +2362,6 @@ static void perf_mmap_data_free_rcu(struct rcu_head *rcu_head) data = container_of(rcu_head, struct perf_mmap_data, rcu_head); perf_mmap_data_free(data); - kfree(data); } static void perf_mmap_data_release(struct perf_event *event) @@ -3253,6 +3268,9 @@ static void perf_event_task_output(struct perf_event *event, static int perf_event_task_match(struct perf_event *event) { + if (event->cpu != -1 && event->cpu != smp_processor_id()) + return 0; + if (event->attr.comm || event->attr.mmap || event->attr.task) return 1; @@ -3278,12 +3296,11 @@ static void perf_event_task_event(struct perf_task_event *task_event) rcu_read_lock(); cpuctx = &get_cpu_var(perf_cpu_context); perf_event_task_ctx(&cpuctx->ctx, task_event); - put_cpu_var(perf_cpu_context); - if (!ctx) ctx = rcu_dereference(task_event->task->perf_event_ctxp); if (ctx) perf_event_task_ctx(ctx, task_event); + put_cpu_var(perf_cpu_context); rcu_read_unlock(); } @@ -3360,6 +3377,9 @@ static void perf_event_comm_output(struct perf_event *event, static int perf_event_comm_match(struct perf_event *event) { + if (event->cpu != -1 && event->cpu != smp_processor_id()) + return 0; + if (event->attr.comm) return 1; @@ -3396,15 +3416,10 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event) rcu_read_lock(); cpuctx = &get_cpu_var(perf_cpu_context); perf_event_comm_ctx(&cpuctx->ctx, comm_event); - put_cpu_var(perf_cpu_context); - - /* - * doesn't really matter which of the child contexts the - * events ends up in. - */ ctx = rcu_dereference(current->perf_event_ctxp); if (ctx) perf_event_comm_ctx(ctx, comm_event); + put_cpu_var(perf_cpu_context); rcu_read_unlock(); } @@ -3479,6 +3494,9 @@ static void perf_event_mmap_output(struct perf_event *event, static int perf_event_mmap_match(struct perf_event *event, struct perf_mmap_event *mmap_event) { + if (event->cpu != -1 && event->cpu != smp_processor_id()) + return 0; + if (event->attr.mmap) return 1; @@ -3552,15 +3570,10 @@ got_name: rcu_read_lock(); cpuctx = &get_cpu_var(perf_cpu_context); perf_event_mmap_ctx(&cpuctx->ctx, mmap_event); - put_cpu_var(perf_cpu_context); - - /* - * doesn't really matter which of the child contexts the - * events ends up in. - */ ctx = rcu_dereference(current->perf_event_ctxp); if (ctx) perf_event_mmap_ctx(ctx, mmap_event); + put_cpu_var(perf_cpu_context); rcu_read_unlock(); kfree(buf); @@ -3851,6 +3864,9 @@ static int perf_swevent_match(struct perf_event *event, struct perf_sample_data *data, struct pt_regs *regs) { + if (event->cpu != -1 && event->cpu != smp_processor_id()) + return 0; + if (!perf_swevent_is_counting(event)) return 0; @@ -4001,6 +4017,8 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) event->pmu->read(event); data.addr = 0; + data.raw = NULL; + data.period = event->hw.last_period; regs = get_irq_regs(); /* * In case we exclude kernel IPs or are somehow not in interrupt @@ -4069,8 +4087,7 @@ static void cpu_clock_perf_event_update(struct perf_event *event) u64 now; now = cpu_clock(cpu); - prev = atomic64_read(&event->hw.prev_count); - atomic64_set(&event->hw.prev_count, now); + prev = atomic64_xchg(&event->hw.prev_count, now); atomic64_add(now - prev, &event->count); } @@ -4275,15 +4292,8 @@ static void bp_perf_event_destroy(struct perf_event *event) static const struct pmu *bp_perf_event_init(struct perf_event *bp) { int err; - /* - * The breakpoint is already filled if we haven't created the counter - * through perf syscall - * FIXME: manage to get trigerred to NULL if it comes from syscalls - */ - if (!bp->callback) - err = register_perf_hw_breakpoint(bp); - else - err = __register_perf_hw_breakpoint(bp); + + err = register_perf_hw_breakpoint(bp); if (err) return ERR_PTR(err); @@ -4297,16 +4307,13 @@ void perf_bp_event(struct perf_event *bp, void *data) struct perf_sample_data sample; struct pt_regs *regs = data; + sample.raw = NULL; sample.addr = bp->attr.bp_addr; if (!perf_exclude_event(bp, regs)) perf_swevent_add(bp, 1, 1, &sample, regs); } #else -static void bp_perf_event_destroy(struct perf_event *event) -{ -} - static const struct pmu *bp_perf_event_init(struct perf_event *bp) { return NULL; @@ -4383,7 +4390,7 @@ perf_event_alloc(struct perf_event_attr *attr, struct perf_event_context *ctx, struct perf_event *group_leader, struct perf_event *parent_event, - perf_callback_t callback, + perf_overflow_handler_t overflow_handler, gfp_t gfpflags) { const struct pmu *pmu; @@ -4426,10 +4433,10 @@ perf_event_alloc(struct perf_event_attr *attr, event->state = PERF_EVENT_STATE_INACTIVE; - if (!callback && parent_event) - callback = parent_event->callback; + if (!overflow_handler && parent_event) + overflow_handler = parent_event->overflow_handler; - event->callback = callback; + event->overflow_handler = overflow_handler; if (attr->disabled) event->state = PERF_EVENT_STATE_OFF; @@ -4564,7 +4571,7 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr, if (attr->type >= PERF_TYPE_MAX) return -EINVAL; - if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3) + if (attr->__reserved_1 || attr->__reserved_2) return -EINVAL; if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) @@ -4769,7 +4776,8 @@ err_put_context: */ struct perf_event * perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, - pid_t pid, perf_callback_t callback) + pid_t pid, + perf_overflow_handler_t overflow_handler) { struct perf_event *event; struct perf_event_context *ctx; @@ -4786,7 +4794,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, } event = perf_event_alloc(attr, cpu, ctx, NULL, - NULL, callback, GFP_KERNEL); + NULL, overflow_handler, GFP_KERNEL); if (IS_ERR(event)) { err = PTR_ERR(event); goto err_put_context; @@ -4991,7 +4999,7 @@ void perf_event_exit_task(struct task_struct *child) * reading child->perf_event_ctxp, we wait until it has * incremented the context's refcount before we do put_ctx below. */ - spin_lock(&child_ctx->lock); + raw_spin_lock(&child_ctx->lock); child->perf_event_ctxp = NULL; /* * If this context is a clone; unclone it so it can't get @@ -5000,7 +5008,7 @@ void perf_event_exit_task(struct task_struct *child) */ unclone_ctx(child_ctx); update_context_time(child_ctx); - spin_unlock_irqrestore(&child_ctx->lock, flags); + raw_spin_unlock_irqrestore(&child_ctx->lock, flags); /* * Report the task dead after unscheduling the events so that we @@ -5083,7 +5091,7 @@ again: */ int perf_event_init_task(struct task_struct *child) { - struct perf_event_context *child_ctx, *parent_ctx; + struct perf_event_context *child_ctx = NULL, *parent_ctx; struct perf_event_context *cloned_ctx; struct perf_event *event; struct task_struct *parent = current; @@ -5099,20 +5107,6 @@ int perf_event_init_task(struct task_struct *child) return 0; /* - * This is executed from the parent task context, so inherit - * events that have been marked for cloning. - * First allocate and initialize a context for the child. - */ - - child_ctx = kmalloc(sizeof(struct perf_event_context), GFP_KERNEL); - if (!child_ctx) - return -ENOMEM; - - __perf_event_init_context(child_ctx, child); - child->perf_event_ctxp = child_ctx; - get_task_struct(child); - - /* * If the parent's context is a clone, pin it so it won't get * swapped under us. */ @@ -5142,6 +5136,26 @@ int perf_event_init_task(struct task_struct *child) continue; } + if (!child->perf_event_ctxp) { + /* + * This is executed from the parent task context, so + * inherit events that have been marked for cloning. + * First allocate and initialize a context for the + * child. + */ + + child_ctx = kzalloc(sizeof(struct perf_event_context), + GFP_KERNEL); + if (!child_ctx) { + ret = -ENOMEM; + goto exit; + } + + __perf_event_init_context(child_ctx, child); + child->perf_event_ctxp = child_ctx; + get_task_struct(child); + } + ret = inherit_group(event, parent, parent_ctx, child, child_ctx); if (ret) { @@ -5170,6 +5184,7 @@ int perf_event_init_task(struct task_struct *child) get_ctx(child_ctx->parent_ctx); } +exit: mutex_unlock(&parent_ctx->mutex); perf_unpin_context(parent_ctx); @@ -5284,11 +5299,11 @@ perf_set_reserve_percpu(struct sysdev_class *class, perf_reserved_percpu = val; for_each_online_cpu(cpu) { cpuctx = &per_cpu(perf_cpu_context, cpu); - spin_lock_irq(&cpuctx->ctx.lock); + raw_spin_lock_irq(&cpuctx->ctx.lock); mpt = min(perf_max_events - cpuctx->ctx.nr_events, perf_max_events - perf_reserved_percpu); cpuctx->max_pertask = mpt; - spin_unlock_irq(&cpuctx->ctx.lock); + raw_spin_unlock_irq(&cpuctx->ctx.lock); } spin_unlock(&perf_resource_lock);