diff options
Diffstat (limited to 'kernel/events')
| -rw-r--r-- | kernel/events/callchain.c | 3 | ||||
| -rw-r--r-- | kernel/events/core.c | 470 | ||||
| -rw-r--r-- | kernel/events/hw_breakpoint.c | 15 | ||||
| -rw-r--r-- | kernel/events/internal.h | 9 | ||||
| -rw-r--r-- | kernel/events/ring_buffer.c | 145 | ||||
| -rw-r--r-- | kernel/events/uprobes.c | 36 |
6 files changed, 498 insertions, 180 deletions
diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 24a77c34e9ad..c2b41a263166 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Performance events callchain code, extracted from core.c: * @@ -5,8 +6,6 @@ * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> - * - * For licensing details see kernel-base/COPYING */ #include <linux/perf_event.h> diff --git a/kernel/events/core.c b/kernel/events/core.c index 26d6edab051a..f85929ce13be 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Performance events core code: * @@ -5,8 +6,6 @@ * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> - * - * For licensing details see kernel-base/COPYING */ #include <linux/fs.h> @@ -385,6 +384,8 @@ static atomic_t nr_namespaces_events __read_mostly; static atomic_t nr_task_events __read_mostly; static atomic_t nr_freq_events __read_mostly; static atomic_t nr_switch_events __read_mostly; +static atomic_t nr_ksymbol_events __read_mostly; +static atomic_t nr_bpf_events __read_mostly; static LIST_HEAD(pmus); static DEFINE_MUTEX(pmus_lock); @@ -1171,7 +1172,7 @@ static void perf_event_ctx_deactivate(struct perf_event_context *ctx) static void get_ctx(struct perf_event_context *ctx) { - WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); + refcount_inc(&ctx->refcount); } static void free_ctx(struct rcu_head *head) @@ -1185,7 +1186,7 @@ static void free_ctx(struct rcu_head *head) static void put_ctx(struct perf_event_context *ctx) { - if (atomic_dec_and_test(&ctx->refcount)) { + if (refcount_dec_and_test(&ctx->refcount)) { if (ctx->parent_ctx) put_ctx(ctx->parent_ctx); if (ctx->task && ctx->task != TASK_TOMBSTONE) @@ -1254,6 +1255,7 @@ static void put_ctx(struct perf_event_context *ctx) * perf_event_context::lock * perf_event::mmap_mutex * mmap_sem + * perf_addr_filters_head::lock * * cpu_hotplug_lock * pmus_lock @@ -1267,7 +1269,7 @@ perf_event_ctx_lock_nested(struct perf_event *event, int nesting) again: rcu_read_lock(); ctx = READ_ONCE(event->ctx); - if (!atomic_inc_not_zero(&ctx->refcount)) { + if (!refcount_inc_not_zero(&ctx->refcount)) { rcu_read_unlock(); goto again; } @@ -1400,7 +1402,7 @@ retry: } if (ctx->task == TASK_TOMBSTONE || - !atomic_inc_not_zero(&ctx->refcount)) { + !refcount_inc_not_zero(&ctx->refcount)) { raw_spin_unlock(&ctx->lock); ctx = NULL; } else { @@ -2007,8 +2009,8 @@ event_sched_out(struct perf_event *event, event->pmu->del(event, 0); event->oncpu = -1; - if (event->pending_disable) { - event->pending_disable = 0; + if (READ_ONCE(event->pending_disable) >= 0) { + WRITE_ONCE(event->pending_disable, -1); state = PERF_EVENT_STATE_OFF; } perf_event_set_state(event, state); @@ -2196,7 +2198,8 @@ EXPORT_SYMBOL_GPL(perf_event_disable); void perf_event_disable_inatomic(struct perf_event *event) { - event->pending_disable = 1; + WRITE_ONCE(event->pending_disable, smp_processor_id()); + /* can fail, see perf_pending_event_disable() */ irq_work_queue(&event->pending); } @@ -2475,6 +2478,16 @@ static void ctx_resched(struct perf_cpu_context *cpuctx, perf_pmu_enable(cpuctx->ctx.pmu); } +void perf_pmu_resched(struct pmu *pmu) +{ + struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); + struct perf_event_context *task_ctx = cpuctx->task_ctx; + + perf_ctx_lock(cpuctx, task_ctx); + ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); + perf_ctx_unlock(cpuctx, task_ctx); +} + /* * Cross CPU call to install and enable a performance event * @@ -2797,7 +2810,7 @@ static int perf_event_stop(struct perf_event *event, int restart) * * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, * we update the addresses of corresponding vmas in - * event::addr_filters_offs array and bump the event::addr_filters_gen; + * event::addr_filter_ranges array and bump the event::addr_filters_gen; * (p2) when an event is scheduled in (pmu::add), it calls * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() * if the generation has changed since the previous call. @@ -4056,7 +4069,7 @@ static void __perf_event_init_context(struct perf_event_context *ctx) INIT_LIST_HEAD(&ctx->event_list); INIT_LIST_HEAD(&ctx->pinned_active); INIT_LIST_HEAD(&ctx->flexible_active); - atomic_set(&ctx->refcount, 1); + refcount_set(&ctx->refcount, 1); } static struct perf_event_context * @@ -4235,8 +4248,9 @@ static bool is_sb_event(struct perf_event *event) if (attr->mmap || attr->mmap_data || attr->mmap2 || attr->comm || attr->comm_exec || - attr->task || - attr->context_switch) + attr->task || attr->ksymbol || + attr->context_switch || + attr->bpf_event) return true; return false; } @@ -4305,6 +4319,10 @@ static void unaccount_event(struct perf_event *event) dec = true; if (has_branch_stack(event)) dec = true; + if (event->attr.ksymbol) + atomic_dec(&nr_ksymbol_events); + if (event->attr.bpf_event) + atomic_dec(&nr_bpf_events); if (dec) { if (!atomic_add_unless(&perf_sched_count, -1, 1)) @@ -4440,7 +4458,7 @@ static void _free_event(struct perf_event *event) perf_event_free_bpf_prog(event); perf_addr_filters_splice(event, NULL); - kfree(event->addr_filters_offs); + kfree(event->addr_filter_ranges); if (event->destroy) event->destroy(event); @@ -4987,6 +5005,9 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg) if (perf_event_check_period(event, value)) return -EINVAL; + if (!event->attr.freq && (value & (1ULL << 63))) + return -EINVAL; + event_function_call(event, __perf_event_period, &value); return 0; @@ -5396,7 +5417,7 @@ struct ring_buffer *ring_buffer_get(struct perf_event *event) rcu_read_lock(); rb = rcu_dereference(event->rb); if (rb) { - if (!atomic_inc_not_zero(&rb->refcount)) + if (!refcount_inc_not_zero(&rb->refcount)) rb = NULL; } rcu_read_unlock(); @@ -5406,7 +5427,7 @@ struct ring_buffer *ring_buffer_get(struct perf_event *event) void ring_buffer_put(struct ring_buffer *rb) { - if (!atomic_dec_and_test(&rb->refcount)) + if (!refcount_dec_and_test(&rb->refcount)) return; WARN_ON_ONCE(!list_empty(&rb->event_list)); @@ -5467,11 +5488,11 @@ static void perf_mmap_close(struct vm_area_struct *vma) /* now it's safe to free the pages */ atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); - vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; + atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); /* this has to be the last one */ rb_free_aux(rb); - WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); + WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); mutex_unlock(&event->mmap_mutex); } @@ -5540,7 +5561,7 @@ again: */ atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); - vma->vm_mm->pinned_vm -= mmap_locked; + atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); free_uid(mmap_user); out_put: @@ -5688,7 +5709,7 @@ accounting: lock_limit = rlimit(RLIMIT_MEMLOCK); lock_limit >>= PAGE_SHIFT; - locked = vma->vm_mm->pinned_vm + extra; + locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && !capable(CAP_IPC_LOCK)) { @@ -5729,7 +5750,7 @@ accounting: unlock: if (!ret) { atomic_long_add(user_extra, &user->locked_vm); - vma->vm_mm->pinned_vm += extra; + atomic64_add(extra, &vma->vm_mm->pinned_vm); atomic_inc(&event->mmap_count); } else if (rb) { @@ -5803,10 +5824,45 @@ void perf_event_wakeup(struct perf_event *event) } } +static void perf_pending_event_disable(struct perf_event *event) +{ + int cpu = READ_ONCE(event->pending_disable); + + if (cpu < 0) + return; + + if (cpu == smp_processor_id()) { + WRITE_ONCE(event->pending_disable, -1); + perf_event_disable_local(event); + return; + } + + /* + * CPU-A CPU-B + * + * perf_event_disable_inatomic() + * @pending_disable = CPU-A; + * irq_work_queue(); + * + * sched-out + * @pending_disable = -1; + * + * sched-in + * perf_event_disable_inatomic() + * @pending_disable = CPU-B; + * irq_work_queue(); // FAILS + * + * irq_work_run() + * perf_pending_event() + * + * But the event runs on CPU-B and wants disabling there. + */ + irq_work_queue_on(&event->pending, cpu); +} + static void perf_pending_event(struct irq_work *entry) { - struct perf_event *event = container_of(entry, - struct perf_event, pending); + struct perf_event *event = container_of(entry, struct perf_event, pending); int rctx; rctx = perf_swevent_get_recursion_context(); @@ -5815,10 +5871,7 @@ static void perf_pending_event(struct irq_work *entry) * and we won't recurse 'further'. */ - if (event->pending_disable) { - event->pending_disable = 0; - perf_event_disable_local(event); - } + perf_pending_event_disable(event); if (event->pending_wakeup) { event->pending_wakeup = 0; @@ -5873,7 +5926,7 @@ static void perf_sample_regs_user(struct perf_regs *regs_user, if (user_mode(regs)) { regs_user->abi = perf_reg_abi(current); regs_user->regs = regs; - } else if (current->mm) { + } else if (!(current->flags & PF_KTHREAD)) { perf_get_regs_user(regs_user, regs, regs_user_copy); } else { regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; @@ -6497,7 +6550,7 @@ void perf_prepare_sample(struct perf_event_header *header, data->phys_addr = perf_virt_to_phys(data->addr); } -static __always_inline void +static __always_inline int __perf_event_output(struct perf_event *event, struct perf_sample_data *data, struct pt_regs *regs, @@ -6507,13 +6560,15 @@ __perf_event_output(struct perf_event *event, { struct perf_output_handle handle; struct perf_event_header header; + int err; /* protect the callchain buffers */ rcu_read_lock(); perf_prepare_sample(&header, data, event, regs); - if (output_begin(&handle, event, header.size)) + err = output_begin(&handle, event, header.size); + if (err) goto exit; perf_output_sample(&handle, &header, data, event); @@ -6522,6 +6577,7 @@ __perf_event_output(struct perf_event *event, exit: rcu_read_unlock(); + return err; } void @@ -6540,12 +6596,12 @@ perf_event_output_backward(struct perf_event *event, __perf_event_output(event, data, regs, perf_output_begin_backward); } -void +int perf_event_output(struct perf_event *event, struct perf_sample_data *data, struct pt_regs *regs) { - __perf_event_output(event, data, regs, perf_output_begin); + return __perf_event_output(event, data, regs, perf_output_begin); } /* @@ -6686,7 +6742,8 @@ static void perf_event_addr_filters_exec(struct perf_event *event, void *data) raw_spin_lock_irqsave(&ifh->lock, flags); list_for_each_entry(filter, &ifh->list, entry) { if (filter->path.dentry) { - event->addr_filters_offs[count] = 0; + event->addr_filter_ranges[count].start = 0; + event->addr_filter_ranges[count].size = 0; restart++; } @@ -7178,6 +7235,7 @@ static void perf_event_mmap_output(struct perf_event *event, struct perf_output_handle handle; struct perf_sample_data sample; int size = mmap_event->event_id.header.size; + u32 type = mmap_event->event_id.header.type; int ret; if (!perf_event_mmap_match(event, data)) @@ -7221,6 +7279,7 @@ static void perf_event_mmap_output(struct perf_event *event, perf_output_end(&handle); out: mmap_event->event_id.header.size = size; + mmap_event->event_id.header.type = type; } static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) @@ -7366,28 +7425,47 @@ static bool perf_addr_filter_match(struct perf_addr_filter *filter, return true; } +static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, + struct vm_area_struct *vma, + struct perf_addr_filter_range *fr) +{ + unsigned long vma_size = vma->vm_end - vma->vm_start; + unsigned long off = vma->vm_pgoff << PAGE_SHIFT; + struct file *file = vma->vm_file; + + if (!perf_addr_filter_match(filter, file, off, vma_size)) + return false; + + if (filter->offset < off) { + fr->start = vma->vm_start; + fr->size = min(vma_size, filter->size - (off - filter->offset)); + } else { + fr->start = vma->vm_start + filter->offset - off; + fr->size = min(vma->vm_end - fr->start, filter->size); + } + + return true; +} + static void __perf_addr_filters_adjust(struct perf_event *event, void *data) { struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); struct vm_area_struct *vma = data; - unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; - struct file *file = vma->vm_file; struct perf_addr_filter *filter; unsigned int restart = 0, count = 0; + unsigned long flags; if (!has_addr_filter(event)) return; - if (!file) + if (!vma->vm_file) return; raw_spin_lock_irqsave(&ifh->lock, flags); list_for_each_entry(filter, &ifh->list, entry) { - if (perf_addr_filter_match(filter, file, off, - vma->vm_end - vma->vm_start)) { - event->addr_filters_offs[count] = vma->vm_start; + if (perf_addr_filter_vma_adjust(filter, vma, + &event->addr_filter_ranges[count])) restart++; - } count++; } @@ -7658,6 +7736,207 @@ static void perf_log_throttle(struct perf_event *event, int enable) perf_output_end(&handle); } +/* + * ksymbol register/unregister tracking + */ + +struct perf_ksymbol_event { + const char *name; + int name_len; + struct { + struct perf_event_header header; + u64 addr; + u32 len; + u16 ksym_type; + u16 flags; + } event_id; +}; + +static int perf_event_ksymbol_match(struct perf_event *event) +{ + return event->attr.ksymbol; +} + +static void perf_event_ksymbol_output(struct perf_event *event, void *data) +{ + struct perf_ksymbol_event *ksymbol_event = data; + struct perf_output_handle handle; + struct perf_sample_data sample; + int ret; + + if (!perf_event_ksymbol_match(event)) + return; + + perf_event_header__init_id(&ksymbol_event->event_id.header, + &sample, event); + ret = perf_output_begin(&handle, event, + ksymbol_event->event_id.header.size); + if (ret) + return; + + perf_output_put(&handle, ksymbol_event->event_id); + __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); + perf_event__output_id_sample(event, &handle, &sample); + + perf_output_end(&handle); +} + +void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, + const char *sym) +{ + struct perf_ksymbol_event ksymbol_event; + char name[KSYM_NAME_LEN]; + u16 flags = 0; + int name_len; + + if (!atomic_read(&nr_ksymbol_events)) + return; + + if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || + ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) + goto err; + + strlcpy(name, sym, KSYM_NAME_LEN); + name_len = strlen(name) + 1; + while (!IS_ALIGNED(name_len, sizeof(u64))) + name[name_len++] = '\0'; + BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); + + if (unregister) + flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; + + ksymbol_event = (struct perf_ksymbol_event){ + .name = name, + .name_len = name_len, + .event_id = { + .header = { + .type = PERF_RECORD_KSYMBOL, + .size = sizeof(ksymbol_event.event_id) + + name_len, + }, + .addr = addr, + .len = len, + .ksym_type = ksym_type, + .flags = flags, + }, + }; + + perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); + return; +err: + WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); +} + +/* + * bpf program load/unload tracking + */ + +struct perf_bpf_event { + struct bpf_prog *prog; + struct { + struct perf_event_header header; + u16 type; + u16 flags; + u32 id; + u8 tag[BPF_TAG_SIZE]; + } event_id; +}; + +static int perf_event_bpf_match(struct perf_event *event) +{ + return event->attr.bpf_event; +} + +static void perf_event_bpf_output(struct perf_event *event, void *data) +{ + struct perf_bpf_event *bpf_event = data; + struct perf_output_handle handle; + struct perf_sample_data sample; + int ret; + + if (!perf_event_bpf_match(event)) + return; + + perf_event_header__init_id(&bpf_event->event_id.header, + &sample, event); + ret = perf_output_begin(&handle, event, + bpf_event->event_id.header.size); + if (ret) + return; + + perf_output_put(&handle, bpf_event->event_id); + perf_event__output_id_sample(event, &handle, &sample); + + perf_output_end(&handle); +} + +static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, + enum perf_bpf_event_type type) +{ + bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; + char sym[KSYM_NAME_LEN]; + int i; + + if (prog->aux->func_cnt == 0) { + bpf_get_prog_name(prog, sym); + perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, + (u64)(unsigned long)prog->bpf_func, + prog->jited_len, unregister, sym); + } else { + for (i = 0; i < prog->aux->func_cnt; i++) { + struct bpf_prog *subprog = prog->aux->func[i]; + + bpf_get_prog_name(subprog, sym); + perf_event_ksymbol( + PERF_RECORD_KSYMBOL_TYPE_BPF, + (u64)(unsigned long)subprog->bpf_func, + subprog->jited_len, unregister, sym); + } + } +} + +void perf_event_bpf_event(struct bpf_prog *prog, + enum perf_bpf_event_type type, + u16 flags) +{ + struct perf_bpf_event bpf_event; + + if (type <= PERF_BPF_EVENT_UNKNOWN || + type >= PERF_BPF_EVENT_MAX) + return; + + switch (type) { + case PERF_BPF_EVENT_PROG_LOAD: + case PERF_BPF_EVENT_PROG_UNLOAD: + if (atomic_read(&nr_ksymbol_events)) + perf_event_bpf_emit_ksymbols(prog, type); + break; + default: + break; + } + + if (!atomic_read(&nr_bpf_events)) + return; + + bpf_event = (struct perf_bpf_event){ + .prog = prog, + .event_id = { + .header = { + .type = PERF_RECORD_BPF_EVENT, + .size = sizeof(bpf_event.event_id), + }, + .type = type, + .flags = flags, + .id = prog->aux->id, + }, + }; + + BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); + + memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); + perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); +} + void perf_event_itrace_started(struct perf_event *event) { event->attach_state |= PERF_ATTACH_ITRACE; @@ -8776,26 +9055,19 @@ static void perf_addr_filters_splice(struct perf_event *event, * @filter; if so, adjust filter's address range. * Called with mm::mmap_sem down for reading. */ -static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, - struct mm_struct *mm) +static void perf_addr_filter_apply(struct perf_addr_filter *filter, + struct mm_struct *mm, + struct perf_addr_filter_range *fr) { struct vm_area_struct *vma; for (vma = mm->mmap; vma; vma = vma->vm_next) { - struct file *file = vma->vm_file; - unsigned long off = vma->vm_pgoff << PAGE_SHIFT; - unsigned long vma_size = vma->vm_end - vma->vm_start; - - if (!file) - continue; - - if (!perf_addr_filter_match(filter, file, off, vma_size)) + if (!vma->vm_file) continue; - return vma->vm_start; + if (perf_addr_filter_vma_adjust(filter, vma, fr)) + return; } - - return 0; } /* @@ -8818,26 +9090,29 @@ static void perf_event_addr_filters_apply(struct perf_event *event) if (task == TASK_TOMBSTONE) return; - if (!ifh->nr_file_filters) - return; - - mm = get_task_mm(event->ctx->task); - if (!mm) - goto restart; + if (ifh->nr_file_filters) { + mm = get_task_mm(event->ctx->task); + if (!mm) + goto restart; - down_read(&mm->mmap_sem); + down_read(&mm->mmap_sem); + } raw_spin_lock_irqsave(&ifh->lock, flags); list_for_each_entry(filter, &ifh->list, entry) { - event->addr_filters_offs[count] = 0; + if (filter->path.dentry) { + /* + * Adjust base offset if the filter is associated to a + * binary that needs to be mapped: + */ + event->addr_filter_ranges[count].start = 0; + event->addr_filter_ranges[count].size = 0; - /* - * Adjust base offset if the filter is associated to a binary - * that needs to be mapped: - */ - if (filter->path.dentry) - event->addr_filters_offs[count] = - perf_addr_filter_apply(filter, mm); + perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); + } else { + event->addr_filter_ranges[count].start = filter->offset; + event->addr_filter_ranges[count].size = filter->size; + } count++; } @@ -8845,9 +9120,11 @@ static void perf_event_addr_filters_apply(struct perf_event *event) event->addr_filters_gen++; raw_spin_unlock_irqrestore(&ifh->lock, flags); - up_read(&mm->mmap_sem); + if (ifh->nr_file_filters) { + up_read(&mm->mmap_sem); - mmput(mm); + mmput(mm); + } restart: perf_event_stop(event, 1); @@ -8951,6 +9228,7 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr, case IF_SRC_KERNELADDR: case IF_SRC_KERNEL: kernel = 1; + /* fall through */ case IF_SRC_FILEADDR: case IF_SRC_FILE: @@ -9758,6 +10036,12 @@ void perf_pmu_unregister(struct pmu *pmu) } EXPORT_SYMBOL_GPL(perf_pmu_unregister); +static inline bool has_extended_regs(struct perf_event *event) +{ + return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || + (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); +} + static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) { struct perf_event_context *ctx = NULL; @@ -9788,6 +10072,19 @@ static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) if (ctx) perf_event_ctx_unlock(event->group_leader, ctx); + if (!ret) { + if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && + has_extended_regs(event)) + ret = -EOPNOTSUPP; + + if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && + event_has_any_exclude_flag(event)) + ret = -EINVAL; + + if (ret && event->destroy) + event->destroy(event); + } + if (ret) module_put(pmu->module); @@ -9916,6 +10213,10 @@ static void account_event(struct perf_event *event) inc = true; if (is_cgroup_event(event)) inc = true; + if (event->attr.ksymbol) + atomic_inc(&nr_ksymbol_events); + if (event->attr.bpf_event) + atomic_inc(&nr_bpf_events); if (inc) { /* @@ -9996,6 +10297,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, init_waitqueue_head(&event->waitq); + event->pending_disable = -1; init_irq_work(&event->pending, perf_pending_event); mutex_init(&event->mmap_mutex); @@ -10098,14 +10400,28 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, goto err_pmu; if (has_addr_filter(event)) { - event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, - sizeof(unsigned long), - GFP_KERNEL); - if (!event->addr_filters_offs) { + event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, + sizeof(struct perf_addr_filter_range), + GFP_KERNEL); + if (!event->addr_filter_ranges) { err = -ENOMEM; goto err_per_task; } + /* + * Clone the parent's vma offsets: they are valid until exec() + * even if the mm is not shared with the parent. + */ + if (event->parent) { + struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); + + raw_spin_lock_irq(&ifh->lock); + memcpy(event->addr_filter_ranges, + event->parent->addr_filter_ranges, + pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); + raw_spin_unlock_irq(&ifh->lock); + } + /* force hw sync on the address filters */ event->addr_filters_gen = 1; } @@ -10124,7 +10440,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, return event; err_addr_filters: - kfree(event->addr_filters_offs); + kfree(event->addr_filter_ranges); err_per_task: exclusive_event_destroy(event); @@ -10407,7 +10723,7 @@ __perf_event_ctx_lock_double(struct perf_event *group_leader, again: rcu_read_lock(); gctx = READ_ONCE(group_leader->ctx); - if (!atomic_inc_not_zero(&gctx->refcount)) { + if (!refcount_inc_not_zero(&gctx->refcount)) { rcu_read_unlock(); goto again; } @@ -11624,7 +11940,7 @@ static void __init perf_event_init_all_cpus(void) } } -void perf_swevent_init_cpu(unsigned int cpu) +static void perf_swevent_init_cpu(unsigned int cpu) { struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c index 5befb338a18d..c5cd852fe86b 100644 --- a/kernel/events/hw_breakpoint.c +++ b/kernel/events/hw_breakpoint.c @@ -1,18 +1,5 @@ +// SPDX-License-Identifier: GPL-2.0+ /* - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - * * Copyright (C) 2007 Alan Stern * Copyright (C) IBM Corporation, 2009 * Copyright (C) 2009, Frederic Weisbecker <fweisbec@gmail.com> diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 6dc725a7e7bc..3aef4191798c 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -4,13 +4,14 @@ #include <linux/hardirq.h> #include <linux/uaccess.h> +#include <linux/refcount.h> /* Buffer handling */ #define RING_BUFFER_WRITABLE 0x01 struct ring_buffer { - atomic_t refcount; + refcount_t refcount; struct rcu_head rcu_head; #ifdef CONFIG_PERF_USE_VMALLOC struct work_struct work; @@ -23,7 +24,7 @@ struct ring_buffer { atomic_t poll; /* POLL_ for wakeups */ local_t head; /* write position */ - local_t nest; /* nested writers */ + unsigned int nest; /* nested writers */ local_t events; /* event limit */ local_t wakeup; /* wakeup stamp */ local_t lost; /* nr records lost */ @@ -40,7 +41,7 @@ struct ring_buffer { /* AUX area */ long aux_head; - local_t aux_nest; + unsigned int aux_nest; long aux_wakeup; /* last aux_watermark boundary crossed by aux_head */ unsigned long aux_pgoff; int aux_nr_pages; @@ -48,7 +49,7 @@ struct ring_buffer { atomic_t aux_mmap_count; unsigned long aux_mmap_locked; void (*free_aux)(void *); - atomic_t aux_refcount; + refcount_t aux_refcount; void **aux_pages; void *aux_priv; diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 5ab4fe3b1dcc..ffb59a4ef4ff 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Performance events ring-buffer code: * @@ -5,8 +6,6 @@ * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> - * - * For licensing details see kernel-base/COPYING */ #include <linux/perf_event.h> @@ -39,7 +38,12 @@ static void perf_output_get_handle(struct perf_output_handle *handle) struct ring_buffer *rb = handle->rb; preempt_disable(); - local_inc(&rb->nest); + + /* + * Avoid an explicit LOAD/STORE such that architectures with memops + * can use them. + */ + (*(volatile unsigned int *)&rb->nest)++; handle->wakeup = local_read(&rb->wakeup); } @@ -47,17 +51,35 @@ static void perf_output_put_handle(struct perf_output_handle *handle) { struct ring_buffer *rb = handle->rb; unsigned long head; + unsigned int nest; + + /* + * If this isn't the outermost nesting, we don't have to update + * @rb->user_page->data_head. + */ + nest = READ_ONCE(rb->nest); + if (nest > 1) { + WRITE_ONCE(rb->nest, nest - 1); + goto out; + } again: + /* + * In order to avoid publishing a head value that goes backwards, + * we must ensure the load of @rb->head happens after we've + * incremented @rb->nest. + * + * Otherwise we can observe a @rb->head value before one published + * by an IRQ/NMI happening between the load and the increment. + */ + barrier(); head = local_read(&rb->head); /* - * IRQ/NMI can happen here, which means we can miss a head update. + * IRQ/NMI can happen here and advance @rb->head, causing our + * load above to be stale. */ - if (!local_dec_and_test(&rb->nest)) - goto out; - /* * Since the mmap() consumer (userspace) can run on a different CPU: * @@ -85,14 +107,23 @@ again: * See perf_output_begin(). */ smp_wmb(); /* B, matches C */ - rb->user_page->data_head = head; + WRITE_ONCE(rb->user_page->data_head, head); /* - * Now check if we missed an update -- rely on previous implied - * compiler barriers to force a re-read. + * We must publish the head before decrementing the nest count, + * otherwise an IRQ/NMI can publish a more recent head value and our + * write will (temporarily) publish a stale value. */ + barrier(); + WRITE_ONCE(rb->nest, 0); + + /* + * Ensure we decrement @rb->nest before we validate the @rb->head. + * Otherwise we cannot be sure we caught the 'last' nested update. + */ + barrier(); if (unlikely(head != local_read(&rb->head))) { - local_inc(&rb->nest); + WRITE_ONCE(rb->nest, 1); goto again; } @@ -285,7 +316,7 @@ ring_buffer_init(struct ring_buffer *rb, long watermark, int flags) else rb->overwrite = 1; - atomic_set(&rb->refcount, 1); + refcount_set(&rb->refcount, 1); INIT_LIST_HEAD(&rb->event_list); spin_lock_init(&rb->event_lock); @@ -331,6 +362,7 @@ void *perf_aux_output_begin(struct perf_output_handle *handle, struct perf_event *output_event = event; unsigned long aux_head, aux_tail; struct ring_buffer *rb; + unsigned int nest; if (output_event->parent) output_event = output_event->parent; @@ -358,16 +390,19 @@ void *perf_aux_output_begin(struct perf_output_handle *handle, if (!atomic_read(&rb->aux_mmap_count)) goto err; - if (!atomic_inc_not_zero(&rb->aux_refcount)) + if (!refcount_inc_not_zero(&rb->aux_refcount)) goto err; + nest = READ_ONCE(rb->aux_nest); /* * Nesting is not supported for AUX area, make sure nested * writers are caught early */ - if (WARN_ON_ONCE(local_xchg(&rb->aux_nest, 1))) + if (WARN_ON_ONCE(nest)) goto err_put; + WRITE_ONCE(rb->aux_nest, nest + 1); + aux_head = rb->aux_head; handle->rb = rb; @@ -393,9 +428,9 @@ void *perf_aux_output_begin(struct perf_output_handle *handle, * store that will be enabled on successful return */ if (!handle->size) { /* A, matches D */ - event->pending_disable = 1; + event->pending_disable = smp_processor_id(); perf_output_wakeup(handle); - local_set(&rb->aux_nest, 0); + WRITE_ONCE(rb->aux_nest, 0); goto err_put; } } @@ -456,38 +491,35 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size) rb->aux_head += size; } - if (size || handle->aux_flags) { - /* - * Only send RECORD_AUX if we have something useful to communicate - * - * Note: the OVERWRITE records by themselves are not considered - * useful, as they don't communicate any *new* information, - * aside from the short-lived offset, that becomes history at - * the next event sched-in and therefore isn't useful. - * The userspace that needs to copy out AUX data in overwrite - * mode should know to use user_page::aux_head for the actual - * offset. So, from now on we don't output AUX records that - * have *only* OVERWRITE flag set. - */ - - if (handle->aux_flags & ~(u64)PERF_AUX_FLAG_OVERWRITE) - perf_event_aux_event(handle->event, aux_head, size, - handle->aux_flags); - } + /* + * Only send RECORD_AUX if we have something useful to communicate + * + * Note: the OVERWRITE records by themselves are not considered + * useful, as they don't communicate any *new* information, + * aside from the short-lived offset, that becomes history at + * the next event sched-in and therefore isn't useful. + * The userspace that needs to copy out AUX data in overwrite + * mode should know to use user_page::aux_head for the actual + * offset. So, from now on we don't output AUX records that + * have *only* OVERWRITE flag set. + */ + if (size || (handle->aux_flags & ~(u64)PERF_AUX_FLAG_OVERWRITE)) + perf_event_aux_event(handle->event, aux_head, size, + handle->aux_flags); - rb->user_page->aux_head = rb->aux_head; + WRITE_ONCE(rb->user_page->aux_head, rb->aux_head); if (rb_need_aux_wakeup(rb)) wakeup = true; if (wakeup) { if (handle->aux_flags & PERF_AUX_FLAG_TRUNCATED) - handle->event->pending_disable = 1; + handle->event->pending_disable = smp_processor_id(); perf_output_wakeup(handle); } handle->event = NULL; - local_set(&rb->aux_nest, 0); + WRITE_ONCE(rb->aux_nest, 0); /* can't be last */ rb_free_aux(rb); ring_buffer_put(rb); @@ -507,7 +539,7 @@ int perf_aux_output_skip(struct perf_output_handle *handle, unsigned long size) rb->aux_head += size; - rb->user_page->aux_head = rb->aux_head; + WRITE_ONCE(rb->user_page->aux_head, rb->aux_head); if (rb_need_aux_wakeup(rb)) { perf_output_wakeup(handle); handle->wakeup = rb->aux_wakeup + rb->aux_watermark; @@ -599,29 +631,26 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event, { bool overwrite = !(flags & RING_BUFFER_WRITABLE); int node = (event->cpu == -1) ? -1 : cpu_to_node(event->cpu); - int ret = -ENOMEM, max_order = 0; + int ret = -ENOMEM, max_order; if (!has_aux(event)) return -EOPNOTSUPP; - if (event->pmu->capabilities & PERF_PMU_CAP_AUX_NO_SG) { - /* - * We need to start with the max_order that fits in nr_pages, - * not the other way around, hence ilog2() and not get_order. - */ - max_order = ilog2(nr_pages); + /* + * We need to start with the max_order that fits in nr_pages, + * not the other way around, hence ilog2() and not get_order. + */ + max_order = ilog2(nr_pages); - /* - * PMU requests more than one contiguous chunks of memory - * for SW double buffering - */ - if ((event->pmu->capabilities & PERF_PMU_CAP_AUX_SW_DOUBLEBUF) && - !overwrite) { - if (!max_order) - return -EINVAL; + /* + * PMU requests more than one contiguous chunks of memory + * for SW double buffering + */ + if (!overwrite) { + if (!max_order) + return -EINVAL; - max_order--; - } + max_order--; } rb->aux_pages = kcalloc_node(nr_pages, sizeof(void *), GFP_KERNEL, @@ -658,7 +687,7 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event, goto out; } - rb->aux_priv = event->pmu->setup_aux(event->cpu, rb->aux_pages, nr_pages, + rb->aux_priv = event->pmu->setup_aux(event, rb->aux_pages, nr_pages, overwrite); if (!rb->aux_priv) goto out; @@ -671,7 +700,7 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event, * we keep a refcount here to make sure either of the two can * reference them safely. */ - atomic_set(&rb->aux_refcount, 1); + refcount_set(&rb->aux_refcount, 1); rb->aux_overwrite = overwrite; rb->aux_watermark = watermark; @@ -690,7 +719,7 @@ out: void rb_free_aux(struct ring_buffer *rb) { - if (atomic_dec_and_test(&rb->aux_refcount)) + if (refcount_dec_and_test(&rb->aux_refcount)) __rb_free_aux(rb); } diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 8aef47ee7bfa..78f61bfc6b79 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1,20 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0+ /* * User-space Probes (UProbes) * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - * * Copyright (C) IBM Corporation, 2008-2012 * Authors: * Srikar Dronamraju @@ -66,7 +53,7 @@ static struct percpu_rw_semaphore dup_mmap_sem; struct uprobe { struct rb_node rb_node; /* node in the rb tree */ - atomic_t ref; + refcount_t ref; struct rw_semaphore register_rwsem; struct rw_semaphore consumer_rwsem; struct list_head pending_list; @@ -174,7 +161,8 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, struct mmu_notifier_range range; struct mem_cgroup *memcg; - mmu_notifier_range_init(&range, mm, addr, addr + PAGE_SIZE); + mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, mm, addr, + addr + PAGE_SIZE); VM_BUG_ON_PAGE(PageTransHuge(old_page), old_page); @@ -560,13 +548,13 @@ set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long v static struct uprobe *get_uprobe(struct uprobe *uprobe) { - atomic_inc(&uprobe->ref); + refcount_inc(&uprobe->ref); return uprobe; } static void put_uprobe(struct uprobe *uprobe) { - if (atomic_dec_and_test(&uprobe->ref)) { + if (refcount_dec_and_test(&uprobe->ref)) { /* * If application munmap(exec_vma) before uprobe_unregister() * gets called, we don't get a chance to remove uprobe from @@ -657,7 +645,7 @@ static struct uprobe *__insert_uprobe(struct uprobe *uprobe) rb_link_node(&uprobe->rb_node, parent, p); rb_insert_color(&uprobe->rb_node, &uprobes_tree); /* get access + creation ref */ - atomic_set(&uprobe->ref, 2); + refcount_set(&uprobe->ref, 2); return u; } @@ -2041,7 +2029,7 @@ static void handler_chain(struct uprobe *uprobe, struct pt_regs *regs) if (uc->handler) { rc = uc->handler(uc, regs); WARN(rc & ~UPROBE_HANDLER_MASK, - "bad rc=0x%x from %pf()\n", rc, uc->handler); + "bad rc=0x%x from %ps()\n", rc, uc->handler); } if (uc->ret_handler) @@ -2307,16 +2295,14 @@ static struct notifier_block uprobe_exception_nb = { .priority = INT_MAX-1, /* notified after kprobes, kgdb */ }; -static int __init init_uprobes(void) +void __init uprobes_init(void) { int i; for (i = 0; i < UPROBES_HASH_SZ; i++) mutex_init(&uprobes_mmap_mutex[i]); - if (percpu_init_rwsem(&dup_mmap_sem)) - return -ENOMEM; + BUG_ON(percpu_init_rwsem(&dup_mmap_sem)); - return register_die_notifier(&uprobe_exception_nb); + BUG_ON(register_die_notifier(&uprobe_exception_nb)); } -__initcall(init_uprobes); |