forked from Minki/linux
perf: Rename perf_mmap_data to perf_buffer
Rename to clarify code. s/perf_mmap_data/perf_buffer/g and selective s/data/buffer/g Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra
Ingo Molnar
parent
68aa00ac0a
commit
ca5135e6b4
@ -602,7 +602,7 @@ enum perf_event_active_state {
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struct file;
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struct perf_mmap_data {
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struct perf_buffer {
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atomic_t refcount;
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struct rcu_head rcu_head;
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#ifdef CONFIG_PERF_USE_VMALLOC
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@ -727,7 +727,7 @@ struct perf_event {
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atomic_t mmap_count;
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int mmap_locked;
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struct user_struct *mmap_user;
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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/* poll related */
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wait_queue_head_t waitq;
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@ -825,7 +825,7 @@ struct perf_cpu_context {
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struct perf_output_handle {
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struct perf_event *event;
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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unsigned long wakeup;
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unsigned long size;
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void *addr;
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@ -1876,7 +1876,7 @@ static void free_event_rcu(struct rcu_head *head)
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}
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static void perf_pending_sync(struct perf_event *event);
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static void perf_mmap_data_put(struct perf_mmap_data *data);
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static void perf_buffer_put(struct perf_buffer *buffer);
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static void free_event(struct perf_event *event)
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{
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@ -1892,9 +1892,9 @@ static void free_event(struct perf_event *event)
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atomic_dec(&nr_task_events);
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}
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if (event->data) {
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perf_mmap_data_put(event->data);
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event->data = NULL;
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if (event->buffer) {
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perf_buffer_put(event->buffer);
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event->buffer = NULL;
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}
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if (event->destroy)
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@ -2119,13 +2119,13 @@ perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
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static unsigned int perf_poll(struct file *file, poll_table *wait)
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{
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struct perf_event *event = file->private_data;
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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unsigned int events = POLL_HUP;
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rcu_read_lock();
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data = rcu_dereference(event->data);
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if (data)
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events = atomic_xchg(&data->poll, 0);
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buffer = rcu_dereference(event->buffer);
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if (buffer)
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events = atomic_xchg(&buffer->poll, 0);
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rcu_read_unlock();
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poll_wait(file, &event->waitq, wait);
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@ -2335,14 +2335,14 @@ static int perf_event_index(struct perf_event *event)
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void perf_event_update_userpage(struct perf_event *event)
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{
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struct perf_event_mmap_page *userpg;
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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rcu_read_lock();
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data = rcu_dereference(event->data);
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if (!data)
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buffer = rcu_dereference(event->buffer);
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if (!buffer)
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goto unlock;
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userpg = data->user_page;
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userpg = buffer->user_page;
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/*
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* Disable preemption so as to not let the corresponding user-space
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@ -2376,15 +2376,15 @@ unlock:
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*/
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static struct page *
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perf_mmap_to_page(struct perf_mmap_data *data, unsigned long pgoff)
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perf_mmap_to_page(struct perf_buffer *buffer, unsigned long pgoff)
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{
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if (pgoff > data->nr_pages)
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if (pgoff > buffer->nr_pages)
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return NULL;
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if (pgoff == 0)
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return virt_to_page(data->user_page);
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return virt_to_page(buffer->user_page);
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return virt_to_page(data->data_pages[pgoff - 1]);
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return virt_to_page(buffer->data_pages[pgoff - 1]);
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}
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static void *perf_mmap_alloc_page(int cpu)
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@ -2400,42 +2400,42 @@ static void *perf_mmap_alloc_page(int cpu)
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return page_address(page);
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}
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static struct perf_mmap_data *
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perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
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static struct perf_buffer *
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perf_buffer_alloc(struct perf_event *event, int nr_pages)
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{
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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unsigned long size;
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int i;
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size = sizeof(struct perf_mmap_data);
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size = sizeof(struct perf_buffer);
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size += nr_pages * sizeof(void *);
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data = kzalloc(size, GFP_KERNEL);
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if (!data)
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buffer = kzalloc(size, GFP_KERNEL);
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if (!buffer)
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goto fail;
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data->user_page = perf_mmap_alloc_page(event->cpu);
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if (!data->user_page)
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buffer->user_page = perf_mmap_alloc_page(event->cpu);
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if (!buffer->user_page)
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goto fail_user_page;
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for (i = 0; i < nr_pages; i++) {
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data->data_pages[i] = perf_mmap_alloc_page(event->cpu);
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if (!data->data_pages[i])
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buffer->data_pages[i] = perf_mmap_alloc_page(event->cpu);
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if (!buffer->data_pages[i])
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goto fail_data_pages;
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}
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data->nr_pages = nr_pages;
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buffer->nr_pages = nr_pages;
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return data;
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return buffer;
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fail_data_pages:
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for (i--; i >= 0; i--)
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free_page((unsigned long)data->data_pages[i]);
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free_page((unsigned long)buffer->data_pages[i]);
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free_page((unsigned long)data->user_page);
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free_page((unsigned long)buffer->user_page);
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fail_user_page:
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kfree(data);
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kfree(buffer);
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fail:
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return NULL;
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@ -2449,17 +2449,17 @@ static void perf_mmap_free_page(unsigned long addr)
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__free_page(page);
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}
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static void perf_mmap_data_free(struct perf_mmap_data *data)
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static void perf_buffer_free(struct perf_buffer *buffer)
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{
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int i;
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perf_mmap_free_page((unsigned long)data->user_page);
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for (i = 0; i < data->nr_pages; i++)
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perf_mmap_free_page((unsigned long)data->data_pages[i]);
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kfree(data);
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perf_mmap_free_page((unsigned long)buffer->user_page);
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for (i = 0; i < buffer->nr_pages; i++)
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perf_mmap_free_page((unsigned long)buffer->data_pages[i]);
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kfree(buffer);
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}
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static inline int page_order(struct perf_mmap_data *data)
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static inline int page_order(struct perf_buffer *buffer)
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{
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return 0;
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}
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@ -2472,18 +2472,18 @@ static inline int page_order(struct perf_mmap_data *data)
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* Required for architectures that have d-cache aliasing issues.
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*/
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static inline int page_order(struct perf_mmap_data *data)
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static inline int page_order(struct perf_buffer *buffer)
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{
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return data->page_order;
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return buffer->page_order;
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}
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static struct page *
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perf_mmap_to_page(struct perf_mmap_data *data, unsigned long pgoff)
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perf_mmap_to_page(struct perf_buffer *buffer, unsigned long pgoff)
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{
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if (pgoff > (1UL << page_order(data)))
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if (pgoff > (1UL << page_order(buffer)))
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return NULL;
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return vmalloc_to_page((void *)data->user_page + pgoff * PAGE_SIZE);
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return vmalloc_to_page((void *)buffer->user_page + pgoff * PAGE_SIZE);
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}
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static void perf_mmap_unmark_page(void *addr)
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@ -2493,57 +2493,57 @@ static void perf_mmap_unmark_page(void *addr)
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page->mapping = NULL;
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}
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static void perf_mmap_data_free_work(struct work_struct *work)
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static void perf_buffer_free_work(struct work_struct *work)
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{
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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void *base;
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int i, nr;
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data = container_of(work, struct perf_mmap_data, work);
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nr = 1 << page_order(data);
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buffer = container_of(work, struct perf_buffer, work);
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nr = 1 << page_order(buffer);
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base = data->user_page;
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base = buffer->user_page;
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for (i = 0; i < nr + 1; i++)
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perf_mmap_unmark_page(base + (i * PAGE_SIZE));
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vfree(base);
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kfree(data);
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kfree(buffer);
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}
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static void perf_mmap_data_free(struct perf_mmap_data *data)
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static void perf_buffer_free(struct perf_buffer *buffer)
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{
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schedule_work(&data->work);
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schedule_work(&buffer->work);
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}
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static struct perf_mmap_data *
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perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
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static struct perf_buffer *
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perf_buffer_alloc(struct perf_event *event, int nr_pages)
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{
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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unsigned long size;
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void *all_buf;
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size = sizeof(struct perf_mmap_data);
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size = sizeof(struct perf_buffer);
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size += sizeof(void *);
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data = kzalloc(size, GFP_KERNEL);
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if (!data)
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buffer = kzalloc(size, GFP_KERNEL);
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if (!buffer)
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goto fail;
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INIT_WORK(&data->work, perf_mmap_data_free_work);
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INIT_WORK(&buffer->work, perf_buffer_free_work);
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all_buf = vmalloc_user((nr_pages + 1) * PAGE_SIZE);
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if (!all_buf)
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goto fail_all_buf;
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data->user_page = all_buf;
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data->data_pages[0] = all_buf + PAGE_SIZE;
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data->page_order = ilog2(nr_pages);
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data->nr_pages = 1;
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buffer->user_page = all_buf;
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buffer->data_pages[0] = all_buf + PAGE_SIZE;
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buffer->page_order = ilog2(nr_pages);
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buffer->nr_pages = 1;
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return data;
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return buffer;
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fail_all_buf:
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kfree(data);
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kfree(buffer);
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fail:
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return NULL;
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@ -2551,15 +2551,15 @@ fail:
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#endif
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static unsigned long perf_data_size(struct perf_mmap_data *data)
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static unsigned long perf_data_size(struct perf_buffer *buffer)
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{
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return data->nr_pages << (PAGE_SHIFT + page_order(data));
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return buffer->nr_pages << (PAGE_SHIFT + page_order(buffer));
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}
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static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
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{
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struct perf_event *event = vma->vm_file->private_data;
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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int ret = VM_FAULT_SIGBUS;
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if (vmf->flags & FAULT_FLAG_MKWRITE) {
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@ -2569,14 +2569,14 @@ static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
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}
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rcu_read_lock();
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data = rcu_dereference(event->data);
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if (!data)
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buffer = rcu_dereference(event->buffer);
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if (!buffer)
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goto unlock;
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if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE))
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goto unlock;
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vmf->page = perf_mmap_to_page(data, vmf->pgoff);
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vmf->page = perf_mmap_to_page(buffer, vmf->pgoff);
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if (!vmf->page)
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goto unlock;
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@ -2592,51 +2592,51 @@ unlock:
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}
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static void
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perf_mmap_data_init(struct perf_event *event, struct perf_mmap_data *data)
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perf_buffer_init(struct perf_event *event, struct perf_buffer *buffer)
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{
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long max_size = perf_data_size(data);
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long max_size = perf_data_size(buffer);
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if (event->attr.watermark) {
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data->watermark = min_t(long, max_size,
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buffer->watermark = min_t(long, max_size,
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event->attr.wakeup_watermark);
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}
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if (!data->watermark)
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data->watermark = max_size / 2;
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if (!buffer->watermark)
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buffer->watermark = max_size / 2;
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atomic_set(&data->refcount, 1);
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rcu_assign_pointer(event->data, data);
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atomic_set(&buffer->refcount, 1);
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rcu_assign_pointer(event->buffer, buffer);
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}
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static void perf_mmap_data_free_rcu(struct rcu_head *rcu_head)
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static void perf_buffer_free_rcu(struct rcu_head *rcu_head)
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{
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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data = container_of(rcu_head, struct perf_mmap_data, rcu_head);
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perf_mmap_data_free(data);
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buffer = container_of(rcu_head, struct perf_buffer, rcu_head);
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perf_buffer_free(buffer);
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}
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static struct perf_mmap_data *perf_mmap_data_get(struct perf_event *event)
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static struct perf_buffer *perf_buffer_get(struct perf_event *event)
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{
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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rcu_read_lock();
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data = rcu_dereference(event->data);
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if (data) {
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if (!atomic_inc_not_zero(&data->refcount))
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data = NULL;
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buffer = rcu_dereference(event->buffer);
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if (buffer) {
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if (!atomic_inc_not_zero(&buffer->refcount))
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buffer = NULL;
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}
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rcu_read_unlock();
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return data;
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return buffer;
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}
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static void perf_mmap_data_put(struct perf_mmap_data *data)
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static void perf_buffer_put(struct perf_buffer *buffer)
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{
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if (!atomic_dec_and_test(&data->refcount))
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if (!atomic_dec_and_test(&buffer->refcount))
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return;
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call_rcu(&data->rcu_head, perf_mmap_data_free_rcu);
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call_rcu(&buffer->rcu_head, perf_buffer_free_rcu);
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}
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static void perf_mmap_open(struct vm_area_struct *vma)
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@ -2651,16 +2651,16 @@ static void perf_mmap_close(struct vm_area_struct *vma)
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struct perf_event *event = vma->vm_file->private_data;
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if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) {
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unsigned long size = perf_data_size(event->data);
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unsigned long size = perf_data_size(event->buffer);
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struct user_struct *user = event->mmap_user;
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struct perf_mmap_data *data = event->data;
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struct perf_buffer *buffer = event->buffer;
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atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm);
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vma->vm_mm->locked_vm -= event->mmap_locked;
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rcu_assign_pointer(event->data, NULL);
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rcu_assign_pointer(event->buffer, NULL);
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mutex_unlock(&event->mmap_mutex);
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perf_mmap_data_put(data);
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perf_buffer_put(buffer);
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free_uid(user);
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}
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}
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@ -2678,7 +2678,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
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unsigned long user_locked, user_lock_limit;
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struct user_struct *user = current_user();
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unsigned long locked, lock_limit;
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struct perf_mmap_data *data;
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struct perf_buffer *buffer;
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unsigned long vma_size;
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unsigned long nr_pages;
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long user_extra, extra;
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@ -2699,7 +2699,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
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nr_pages = (vma_size / PAGE_SIZE) - 1;
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/*
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* If we have data pages ensure they're a power-of-two number, so we
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* If we have buffer pages ensure they're a power-of-two number, so we
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* can do bitmasks instead of modulo.
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*/
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if (nr_pages != 0 && !is_power_of_2(nr_pages))
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@ -2713,9 +2713,9 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
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WARN_ON_ONCE(event->ctx->parent_ctx);
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mutex_lock(&event->mmap_mutex);
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if (event->data) {
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if (event->data->nr_pages == nr_pages)
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atomic_inc(&event->data->refcount);
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if (event->buffer) {
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if (event->buffer->nr_pages == nr_pages)
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atomic_inc(&event->buffer->refcount);
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else
|
||||
ret = -EINVAL;
|
||||
goto unlock;
|
||||
@ -2745,17 +2745,17 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
|
||||
goto unlock;
|
||||
}
|
||||
|
||||
WARN_ON(event->data);
|
||||
WARN_ON(event->buffer);
|
||||
|
||||
data = perf_mmap_data_alloc(event, nr_pages);
|
||||
if (!data) {
|
||||
buffer = perf_buffer_alloc(event, nr_pages);
|
||||
if (!buffer) {
|
||||
ret = -ENOMEM;
|
||||
goto unlock;
|
||||
}
|
||||
|
||||
perf_mmap_data_init(event, data);
|
||||
perf_buffer_init(event, buffer);
|
||||
if (vma->vm_flags & VM_WRITE)
|
||||
event->data->writable = 1;
|
||||
event->buffer->writable = 1;
|
||||
|
||||
atomic_long_add(user_extra, &user->locked_vm);
|
||||
event->mmap_locked = extra;
|
||||
@ -2964,15 +2964,15 @@ EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks);
|
||||
/*
|
||||
* Output
|
||||
*/
|
||||
static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail,
|
||||
static bool perf_output_space(struct perf_buffer *buffer, unsigned long tail,
|
||||
unsigned long offset, unsigned long head)
|
||||
{
|
||||
unsigned long mask;
|
||||
|
||||
if (!data->writable)
|
||||
if (!buffer->writable)
|
||||
return true;
|
||||
|
||||
mask = perf_data_size(data) - 1;
|
||||
mask = perf_data_size(buffer) - 1;
|
||||
|
||||
offset = (offset - tail) & mask;
|
||||
head = (head - tail) & mask;
|
||||
@ -2985,7 +2985,7 @@ static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail,
|
||||
|
||||
static void perf_output_wakeup(struct perf_output_handle *handle)
|
||||
{
|
||||
atomic_set(&handle->data->poll, POLL_IN);
|
||||
atomic_set(&handle->buffer->poll, POLL_IN);
|
||||
|
||||
if (handle->nmi) {
|
||||
handle->event->pending_wakeup = 1;
|
||||
@ -3005,45 +3005,45 @@ static void perf_output_wakeup(struct perf_output_handle *handle)
|
||||
*/
|
||||
static void perf_output_get_handle(struct perf_output_handle *handle)
|
||||
{
|
||||
struct perf_mmap_data *data = handle->data;
|
||||
struct perf_buffer *buffer = handle->buffer;
|
||||
|
||||
preempt_disable();
|
||||
local_inc(&data->nest);
|
||||
handle->wakeup = local_read(&data->wakeup);
|
||||
local_inc(&buffer->nest);
|
||||
handle->wakeup = local_read(&buffer->wakeup);
|
||||
}
|
||||
|
||||
static void perf_output_put_handle(struct perf_output_handle *handle)
|
||||
{
|
||||
struct perf_mmap_data *data = handle->data;
|
||||
struct perf_buffer *buffer = handle->buffer;
|
||||
unsigned long head;
|
||||
|
||||
again:
|
||||
head = local_read(&data->head);
|
||||
head = local_read(&buffer->head);
|
||||
|
||||
/*
|
||||
* IRQ/NMI can happen here, which means we can miss a head update.
|
||||
*/
|
||||
|
||||
if (!local_dec_and_test(&data->nest))
|
||||
if (!local_dec_and_test(&buffer->nest))
|
||||
goto out;
|
||||
|
||||
/*
|
||||
* Publish the known good head. Rely on the full barrier implied
|
||||
* by atomic_dec_and_test() order the data->head read and this
|
||||
* by atomic_dec_and_test() order the buffer->head read and this
|
||||
* write.
|
||||
*/
|
||||
data->user_page->data_head = head;
|
||||
buffer->user_page->data_head = head;
|
||||
|
||||
/*
|
||||
* Now check if we missed an update, rely on the (compiler)
|
||||
* barrier in atomic_dec_and_test() to re-read data->head.
|
||||
* barrier in atomic_dec_and_test() to re-read buffer->head.
|
||||
*/
|
||||
if (unlikely(head != local_read(&data->head))) {
|
||||
local_inc(&data->nest);
|
||||
if (unlikely(head != local_read(&buffer->head))) {
|
||||
local_inc(&buffer->nest);
|
||||
goto again;
|
||||
}
|
||||
|
||||
if (handle->wakeup != local_read(&data->wakeup))
|
||||
if (handle->wakeup != local_read(&buffer->wakeup))
|
||||
perf_output_wakeup(handle);
|
||||
|
||||
out:
|
||||
@ -3063,12 +3063,12 @@ __always_inline void perf_output_copy(struct perf_output_handle *handle,
|
||||
buf += size;
|
||||
handle->size -= size;
|
||||
if (!handle->size) {
|
||||
struct perf_mmap_data *data = handle->data;
|
||||
struct perf_buffer *buffer = handle->buffer;
|
||||
|
||||
handle->page++;
|
||||
handle->page &= data->nr_pages - 1;
|
||||
handle->addr = data->data_pages[handle->page];
|
||||
handle->size = PAGE_SIZE << page_order(data);
|
||||
handle->page &= buffer->nr_pages - 1;
|
||||
handle->addr = buffer->data_pages[handle->page];
|
||||
handle->size = PAGE_SIZE << page_order(buffer);
|
||||
}
|
||||
} while (len);
|
||||
}
|
||||
@ -3077,7 +3077,7 @@ int perf_output_begin(struct perf_output_handle *handle,
|
||||
struct perf_event *event, unsigned int size,
|
||||
int nmi, int sample)
|
||||
{
|
||||
struct perf_mmap_data *data;
|
||||
struct perf_buffer *buffer;
|
||||
unsigned long tail, offset, head;
|
||||
int have_lost;
|
||||
struct {
|
||||
@ -3093,19 +3093,19 @@ int perf_output_begin(struct perf_output_handle *handle,
|
||||
if (event->parent)
|
||||
event = event->parent;
|
||||
|
||||
data = rcu_dereference(event->data);
|
||||
if (!data)
|
||||
buffer = rcu_dereference(event->buffer);
|
||||
if (!buffer)
|
||||
goto out;
|
||||
|
||||
handle->data = data;
|
||||
handle->buffer = buffer;
|
||||
handle->event = event;
|
||||
handle->nmi = nmi;
|
||||
handle->sample = sample;
|
||||
|
||||
if (!data->nr_pages)
|
||||
if (!buffer->nr_pages)
|
||||
goto out;
|
||||
|
||||
have_lost = local_read(&data->lost);
|
||||
have_lost = local_read(&buffer->lost);
|
||||
if (have_lost)
|
||||
size += sizeof(lost_event);
|
||||
|
||||
@ -3117,30 +3117,30 @@ int perf_output_begin(struct perf_output_handle *handle,
|
||||
* tail pointer. So that all reads will be completed before the
|
||||
* write is issued.
|
||||
*/
|
||||
tail = ACCESS_ONCE(data->user_page->data_tail);
|
||||
tail = ACCESS_ONCE(buffer->user_page->data_tail);
|
||||
smp_rmb();
|
||||
offset = head = local_read(&data->head);
|
||||
offset = head = local_read(&buffer->head);
|
||||
head += size;
|
||||
if (unlikely(!perf_output_space(data, tail, offset, head)))
|
||||
if (unlikely(!perf_output_space(buffer, tail, offset, head)))
|
||||
goto fail;
|
||||
} while (local_cmpxchg(&data->head, offset, head) != offset);
|
||||
} while (local_cmpxchg(&buffer->head, offset, head) != offset);
|
||||
|
||||
if (head - local_read(&data->wakeup) > data->watermark)
|
||||
local_add(data->watermark, &data->wakeup);
|
||||
if (head - local_read(&buffer->wakeup) > buffer->watermark)
|
||||
local_add(buffer->watermark, &buffer->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->page = offset >> (PAGE_SHIFT + page_order(buffer));
|
||||
handle->page &= buffer->nr_pages - 1;
|
||||
handle->size = offset & ((PAGE_SIZE << page_order(buffer)) - 1);
|
||||
handle->addr = buffer->data_pages[handle->page];
|
||||
handle->addr += handle->size;
|
||||
handle->size = (PAGE_SIZE << page_order(data)) - handle->size;
|
||||
handle->size = (PAGE_SIZE << page_order(buffer)) - handle->size;
|
||||
|
||||
if (have_lost) {
|
||||
lost_event.header.type = PERF_RECORD_LOST;
|
||||
lost_event.header.misc = 0;
|
||||
lost_event.header.size = sizeof(lost_event);
|
||||
lost_event.id = event->id;
|
||||
lost_event.lost = local_xchg(&data->lost, 0);
|
||||
lost_event.lost = local_xchg(&buffer->lost, 0);
|
||||
|
||||
perf_output_put(handle, lost_event);
|
||||
}
|
||||
@ -3148,7 +3148,7 @@ int perf_output_begin(struct perf_output_handle *handle,
|
||||
return 0;
|
||||
|
||||
fail:
|
||||
local_inc(&data->lost);
|
||||
local_inc(&buffer->lost);
|
||||
perf_output_put_handle(handle);
|
||||
out:
|
||||
rcu_read_unlock();
|
||||
@ -3159,15 +3159,15 @@ out:
|
||||
void perf_output_end(struct perf_output_handle *handle)
|
||||
{
|
||||
struct perf_event *event = handle->event;
|
||||
struct perf_mmap_data *data = handle->data;
|
||||
struct perf_buffer *buffer = handle->buffer;
|
||||
|
||||
int wakeup_events = event->attr.wakeup_events;
|
||||
|
||||
if (handle->sample && wakeup_events) {
|
||||
int events = local_inc_return(&data->events);
|
||||
int events = local_inc_return(&buffer->events);
|
||||
if (events >= wakeup_events) {
|
||||
local_sub(wakeup_events, &data->events);
|
||||
local_inc(&data->wakeup);
|
||||
local_sub(wakeup_events, &buffer->events);
|
||||
local_inc(&buffer->wakeup);
|
||||
}
|
||||
}
|
||||
|
||||
@ -5010,7 +5010,7 @@ err_size:
|
||||
static int
|
||||
perf_event_set_output(struct perf_event *event, struct perf_event *output_event)
|
||||
{
|
||||
struct perf_mmap_data *data = NULL, *old_data = NULL;
|
||||
struct perf_buffer *buffer = NULL, *old_buffer = NULL;
|
||||
int ret = -EINVAL;
|
||||
|
||||
if (!output_event)
|
||||
@ -5040,19 +5040,19 @@ set:
|
||||
|
||||
if (output_event) {
|
||||
/* get the buffer we want to redirect to */
|
||||
data = perf_mmap_data_get(output_event);
|
||||
if (!data)
|
||||
buffer = perf_buffer_get(output_event);
|
||||
if (!buffer)
|
||||
goto unlock;
|
||||
}
|
||||
|
||||
old_data = event->data;
|
||||
rcu_assign_pointer(event->data, data);
|
||||
old_buffer = event->buffer;
|
||||
rcu_assign_pointer(event->buffer, buffer);
|
||||
ret = 0;
|
||||
unlock:
|
||||
mutex_unlock(&event->mmap_mutex);
|
||||
|
||||
if (old_data)
|
||||
perf_mmap_data_put(old_data);
|
||||
if (old_buffer)
|
||||
perf_buffer_put(old_buffer);
|
||||
out:
|
||||
return ret;
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user