Merge branch 'drm-intel-next' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt...
[pandora-kernel.git] / kernel / perf_event.c
index 45b7aec..bd7ce8c 100644 (file)
@@ -2297,11 +2297,6 @@ unlock:
        rcu_read_unlock();
 }
 
-static unsigned long perf_data_size(struct perf_mmap_data *data)
-{
-       return data->nr_pages << (PAGE_SHIFT + data->data_order);
-}
-
 #ifndef CONFIG_PERF_USE_VMALLOC
 
 /*
@@ -2359,7 +2354,6 @@ perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
                        goto fail_data_pages;
        }
 
-       data->data_order = 0;
        data->nr_pages = nr_pages;
 
        return data;
@@ -2395,6 +2389,11 @@ static void perf_mmap_data_free(struct perf_mmap_data *data)
        kfree(data);
 }
 
+static inline int page_order(struct perf_mmap_data *data)
+{
+       return 0;
+}
+
 #else
 
 /*
@@ -2403,10 +2402,15 @@ static void perf_mmap_data_free(struct perf_mmap_data *data)
  * Required for architectures that have d-cache aliasing issues.
  */
 
+static inline int page_order(struct perf_mmap_data *data)
+{
+       return data->page_order;
+}
+
 static struct page *
 perf_mmap_to_page(struct perf_mmap_data *data, unsigned long pgoff)
 {
-       if (pgoff > (1UL << data->data_order))
+       if (pgoff > (1UL << page_order(data)))
                return NULL;
 
        return vmalloc_to_page((void *)data->user_page + pgoff * PAGE_SIZE);
@@ -2426,7 +2430,7 @@ static void perf_mmap_data_free_work(struct work_struct *work)
        int i, nr;
 
        data = container_of(work, struct perf_mmap_data, work);
-       nr = 1 << data->data_order;
+       nr = 1 << page_order(data);
 
        base = data->user_page;
        for (i = 0; i < nr + 1; i++)
@@ -2465,7 +2469,7 @@ perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
 
        data->user_page = all_buf;
        data->data_pages[0] = all_buf + PAGE_SIZE;
-       data->data_order = ilog2(nr_pages);
+       data->page_order = ilog2(nr_pages);
        data->nr_pages = 1;
 
        return data;
@@ -2479,6 +2483,11 @@ fail:
 
 #endif
 
+static unsigned long perf_data_size(struct perf_mmap_data *data)
+{
+       return data->nr_pages << (PAGE_SHIFT + page_order(data));
+}
+
 static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
        struct perf_event *event = vma->vm_file->private_data;
@@ -2958,42 +2967,26 @@ again:
        preempt_enable();
 }
 
-void perf_output_copy(struct perf_output_handle *handle,
+__always_inline void perf_output_copy(struct perf_output_handle *handle,
                      const void *buf, unsigned int len)
 {
-       unsigned int pages_mask;
-       unsigned long offset;
-       unsigned int size;
-       void **pages;
-
-       offset          = handle->offset;
-       pages_mask      = handle->data->nr_pages - 1;
-       pages           = handle->data->data_pages;
-
        do {
-               unsigned long page_offset;
-               unsigned long page_size;
-               int nr;
+               unsigned long size = min_t(unsigned long, handle->size, len);
 
-               nr          = (offset >> PAGE_SHIFT) & pages_mask;
-               page_size   = 1UL << (handle->data->data_order + PAGE_SHIFT);
-               page_offset = offset & (page_size - 1);
-               size        = min_t(unsigned int, page_size - page_offset, len);
+               memcpy(handle->addr, buf, size);
 
-               memcpy(pages[nr] + page_offset, buf, size);
+               len -= size;
+               handle->addr += size;
+               handle->size -= size;
+               if (!handle->size) {
+                       struct perf_mmap_data *data = handle->data;
 
-               len         -= size;
-               buf         += size;
-               offset      += size;
+                       handle->page++;
+                       handle->page &= data->nr_pages - 1;
+                       handle->addr = data->data_pages[handle->page];
+                       handle->size = PAGE_SIZE << page_order(data);
+               }
        } while (len);
-
-       handle->offset = offset;
-
-       /*
-        * Check we didn't copy past our reservation window, taking the
-        * possible unsigned int wrap into account.
-        */
-       WARN_ON_ONCE(((long)(handle->head - handle->offset)) < 0);
 }
 
 int perf_output_begin(struct perf_output_handle *handle,
@@ -3053,11 +3046,15 @@ int perf_output_begin(struct perf_output_handle *handle,
                        goto fail;
        } while (local_cmpxchg(&data->head, offset, head) != offset);
 
-       handle->offset  = offset;
-       handle->head    = head;
+       if (head - local_read(&data->wakeup) > data->watermark)
+               local_add(data->watermark, &data->wakeup);
 
-       if (head - tail > data->watermark)
-               local_inc(&data->wakeup);
+       handle->page = offset >> (PAGE_SHIFT + page_order(data));
+       handle->page &= data->nr_pages - 1;
+       handle->size = offset & ((PAGE_SIZE << page_order(data)) - 1);
+       handle->addr = data->data_pages[handle->page];
+       handle->addr += handle->size;
+       handle->size = (PAGE_SIZE << page_order(data)) - handle->size;
 
        if (have_lost) {
                lost_event.header.type = PERF_RECORD_LOST;
@@ -4005,9 +4002,6 @@ static void perf_swevent_add(struct perf_event *event, u64 nr,
        perf_swevent_overflow(event, 0, nmi, data, regs);
 }
 
-static int perf_tp_event_match(struct perf_event *event,
-                               struct perf_sample_data *data);
-
 static int perf_exclude_event(struct perf_event *event,
                              struct pt_regs *regs)
 {
@@ -4037,10 +4031,6 @@ static int perf_swevent_match(struct perf_event *event,
        if (perf_exclude_event(event, regs))
                return 0;
 
-       if (event->attr.type == PERF_TYPE_TRACEPOINT &&
-           !perf_tp_event_match(event, data))
-               return 0;
-
        return 1;
 }
 
@@ -4122,7 +4112,7 @@ end:
 
 int perf_swevent_get_recursion_context(void)
 {
-       struct perf_cpu_context *cpuctx = &get_cpu_var(perf_cpu_context);
+       struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
        int rctx;
 
        if (in_nmi())
@@ -4134,10 +4124,8 @@ int perf_swevent_get_recursion_context(void)
        else
                rctx = 0;
 
-       if (cpuctx->recursion[rctx]) {
-               put_cpu_var(perf_cpu_context);
+       if (cpuctx->recursion[rctx])
                return -1;
-       }
 
        cpuctx->recursion[rctx]++;
        barrier();
@@ -4151,7 +4139,6 @@ void perf_swevent_put_recursion_context(int rctx)
        struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
        barrier();
        cpuctx->recursion[rctx]--;
-       put_cpu_var(perf_cpu_context);
 }
 EXPORT_SYMBOL_GPL(perf_swevent_put_recursion_context);
 
@@ -4162,6 +4149,7 @@ void __perf_sw_event(u32 event_id, u64 nr, int nmi,
        struct perf_sample_data data;
        int rctx;
 
+       preempt_disable_notrace();
        rctx = perf_swevent_get_recursion_context();
        if (rctx < 0)
                return;
@@ -4171,6 +4159,7 @@ void __perf_sw_event(u32 event_id, u64 nr, int nmi,
        do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, nmi, &data, regs);
 
        perf_swevent_put_recursion_context(rctx);
+       preempt_enable_notrace();
 }
 
 static void perf_swevent_read(struct perf_event *event)
@@ -4486,11 +4475,46 @@ static int swevent_hlist_get(struct perf_event *event)
 
 #ifdef CONFIG_EVENT_TRACING
 
-void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
-                  int entry_size, struct pt_regs *regs, void *event)
+static const struct pmu perf_ops_tracepoint = {
+       .enable         = perf_trace_enable,
+       .disable        = perf_trace_disable,
+       .read           = perf_swevent_read,
+       .unthrottle     = perf_swevent_unthrottle,
+};
+
+static int perf_tp_filter_match(struct perf_event *event,
+                               struct perf_sample_data *data)
+{
+       void *record = data->raw->data;
+
+       if (likely(!event->filter) || filter_match_preds(event->filter, record))
+               return 1;
+       return 0;
+}
+
+static int perf_tp_event_match(struct perf_event *event,
+                               struct perf_sample_data *data,
+                               struct pt_regs *regs)
+{
+       /*
+        * All tracepoints are from kernel-space.
+        */
+       if (event->attr.exclude_kernel)
+               return 0;
+
+       if (!perf_tp_filter_match(event, data))
+               return 0;
+
+       return 1;
+}
+
+void perf_tp_event(u64 addr, u64 count, void *record, int entry_size,
+                  struct pt_regs *regs, struct hlist_head *head)
 {
-       const int type = PERF_TYPE_TRACEPOINT;
        struct perf_sample_data data;
+       struct perf_event *event;
+       struct hlist_node *node;
+
        struct perf_raw_record raw = {
                .size = entry_size,
                .data = record,
@@ -4499,30 +4523,18 @@ void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
        perf_sample_data_init(&data, addr);
        data.raw = &raw;
 
-       if (!event) {
-               do_perf_sw_event(type, event_id, count, 1, &data, regs);
-               return;
+       rcu_read_lock();
+       hlist_for_each_entry_rcu(event, node, head, hlist_entry) {
+               if (perf_tp_event_match(event, &data, regs))
+                       perf_swevent_add(event, count, 1, &data, regs);
        }
-
-       if (perf_swevent_match(event, type, event_id, &data, regs))
-               perf_swevent_add(event, count, 1, &data, regs);
+       rcu_read_unlock();
 }
 EXPORT_SYMBOL_GPL(perf_tp_event);
 
-static int perf_tp_event_match(struct perf_event *event,
-                               struct perf_sample_data *data)
-{
-       void *record = data->raw->data;
-
-       if (likely(!event->filter) || filter_match_preds(event->filter, record))
-               return 1;
-       return 0;
-}
-
 static void tp_perf_event_destroy(struct perf_event *event)
 {
-       perf_trace_disable(event->attr.config);
-       swevent_hlist_put(event);
+       perf_trace_destroy(event);
 }
 
 static const struct pmu *tp_perf_event_init(struct perf_event *event)
@@ -4538,17 +4550,13 @@ static const struct pmu *tp_perf_event_init(struct perf_event *event)
                        !capable(CAP_SYS_ADMIN))
                return ERR_PTR(-EPERM);
 
-       if (perf_trace_enable(event->attr.config, event))
+       err = perf_trace_init(event);
+       if (err)
                return NULL;
 
        event->destroy = tp_perf_event_destroy;
-       err = swevent_hlist_get(event);
-       if (err) {
-               perf_trace_disable(event->attr.config);
-               return ERR_PTR(err);
-       }
 
-       return &perf_ops_generic;
+       return &perf_ops_tracepoint;
 }
 
 static int perf_event_set_filter(struct perf_event *event, void __user *arg)
@@ -4576,12 +4584,6 @@ static void perf_event_free_filter(struct perf_event *event)
 
 #else
 
-static int perf_tp_event_match(struct perf_event *event,
-                               struct perf_sample_data *data)
-{
-       return 1;
-}
-
 static const struct pmu *tp_perf_event_init(struct perf_event *event)
 {
        return NULL;
@@ -4918,6 +4920,13 @@ static int perf_event_set_output(struct perf_event *event, int output_fd)
        int fput_needed = 0;
        int ret = -EINVAL;
 
+       /*
+        * Don't allow output of inherited per-task events. This would
+        * create performance issues due to cross cpu access.
+        */
+       if (event->cpu == -1 && event->attr.inherit)
+               return -EINVAL;
+
        if (!output_fd)
                goto set;
 
@@ -4938,6 +4947,18 @@ static int perf_event_set_output(struct perf_event *event, int output_fd)
        if (event->data)
                goto out;
 
+       /*
+        * Don't allow cross-cpu buffers
+        */
+       if (output_event->cpu != event->cpu)
+               goto out;
+
+       /*
+        * If its not a per-cpu buffer, it must be the same task.
+        */
+       if (output_event->cpu == -1 && output_event->ctx != event->ctx)
+               goto out;
+
        atomic_long_inc(&output_file->f_count);
 
 set:
@@ -4978,8 +4999,8 @@ SYSCALL_DEFINE5(perf_event_open,
        struct perf_event_context *ctx;
        struct file *event_file = NULL;
        struct file *group_file = NULL;
+       int event_fd;
        int fput_needed = 0;
-       int fput_needed2 = 0;
        int err;
 
        /* for future expandability... */
@@ -5000,12 +5021,18 @@ SYSCALL_DEFINE5(perf_event_open,
                        return -EINVAL;
        }
 
+       event_fd = get_unused_fd_flags(O_RDWR);
+       if (event_fd < 0)
+               return event_fd;
+
        /*
         * Get the target context (task or percpu):
         */
        ctx = find_get_context(pid, cpu);
-       if (IS_ERR(ctx))
-               return PTR_ERR(ctx);
+       if (IS_ERR(ctx)) {
+               err = PTR_ERR(ctx);
+               goto err_fd;
+       }
 
        /*
         * Look up the group leader (we will attach this event to it):
@@ -5045,13 +5072,11 @@ SYSCALL_DEFINE5(perf_event_open,
        if (IS_ERR(event))
                goto err_put_context;
 
-       err = anon_inode_getfd("[perf_event]", &perf_fops, event, O_RDWR);
-       if (err < 0)
-               goto err_free_put_context;
-
-       event_file = fget_light(err, &fput_needed2);
-       if (!event_file)
+       event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, O_RDWR);
+       if (IS_ERR(event_file)) {
+               err = PTR_ERR(event_file);
                goto err_free_put_context;
+       }
 
        if (flags & PERF_FLAG_FD_OUTPUT) {
                err = perf_event_set_output(event, group_fd);
@@ -5072,19 +5097,19 @@ SYSCALL_DEFINE5(perf_event_open,
        list_add_tail(&event->owner_entry, &current->perf_event_list);
        mutex_unlock(&current->perf_event_mutex);
 
-err_fput_free_put_context:
-       fput_light(event_file, fput_needed2);
+       fput_light(group_file, fput_needed);
+       fd_install(event_fd, event_file);
+       return event_fd;
 
+err_fput_free_put_context:
+       fput(event_file);
 err_free_put_context:
-       if (err < 0)
-               free_event(event);
-
+       free_event(event);
 err_put_context:
-       if (err < 0)
-               put_ctx(ctx);
-
        fput_light(group_file, fput_needed);
-
+       put_ctx(ctx);
+err_fd:
+       put_unused_fd(event_fd);
        return err;
 }