kernel/trace/ring_buffer.c

402 	struct buffer_page	*tail_page;
446  * head_page == tail_page && head == tail then buffer is empty.
461 	struct buffer_page		*tail_page;	/* write to tail */
586 	struct buffer_page *tail_page = READ_ONCE(cpu_buffer->tail_page);
595 		if (page == tail_page || WARN_ON_ONCE(stop++ > 100))
663 		return rb_fix_abs_ts(ts, cpu_buffer->tail_page->page->time_stamp);
1378 			       struct buffer_page *tail_page,
1407 	if (tail_page == READ_ONCE(cpu_buffer->tail_page)) {
1432 		/* Either we update tail_page or an interrupt does */
1433 		if (try_cmpxchg(&cpu_buffer->tail_page, &tail_page, next_page))
1628 	cpu_buffer->tail_page = cpu_buffer->commit_page = cpu_buffer->head_page;
1807 	struct list_head *tail_page, *to_remove, *next_page;
1827 	tail_page = &cpu_buffer->tail_page->list;
1833 	if (cpu_buffer->tail_page == cpu_buffer->reader_page)
1834 		tail_page = rb_list_head(tail_page->next);
1835 	to_remove = tail_page;
1851 	 * Now we remove all pages between tail_page and next_page.
1855 	tail_page->next = (struct list_head *)((unsigned long)next_page |
1858 	next_page->prev = tail_page;
2369 		    struct buffer_page *tail_page,
2384 	type = rb_head_page_set_update(cpu_buffer, next_page, tail_page,
2493 		buffer_tail_page = READ_ONCE(cpu_buffer->tail_page);
2498 		if (buffer_tail_page != tail_page &&
2512 					      tail_page,
2527 	struct buffer_page *tail_page = info->tail_page;
2533 	 * must fill the old tail_page with padding.
2542 			tail_page->real_end = 0;
2544 		local_sub(length, &tail_page->write);
2548 	event = __rb_page_index(tail_page, tail);
2555 	tail_page->real_end = tail;
2579 		local_sub(length, &tail_page->write);
2592 	/* Make sure the padding is visible before the tail_page->write update */
2597 	local_sub(length, &tail_page->write);
2609 	struct buffer_page *tail_page = info->tail_page;
2615 	next_page = tail_page;
2643 	if (rb_is_head_page(next_page, &tail_page->list)) {
2660 						  tail_page,
2678 				      cpu_buffer->tail_page) &&
2687 	rb_tail_page_update(cpu_buffer, tail_page, next_page);
2882 	bpage = READ_ONCE(cpu_buffer->tail_page);
2885 	 * Make sure the tail_page is still the same and
2957 	while (cpu_buffer->commit_page != READ_ONCE(cpu_buffer->tail_page)) {
2961 			       rb_is_reader_page(cpu_buffer->tail_page)))
2965 		 * of the tail_page did it for this page.
2994 	if (unlikely(cpu_buffer->commit_page != READ_ONCE(cpu_buffer->tail_page)))
3422 	bpage = info->tail_page->page;
3505 	struct buffer_page *tail_page;
3508 	/* Don't let the compiler play games with cpu_buffer->tail_page */
3509 	tail_page = info->tail_page = READ_ONCE(cpu_buffer->tail_page);
3511  /*A*/	w = local_read(&tail_page->write) & RB_WRITE_MASK;
3543  /*C*/	write = local_add_return(info->length, &tail_page->write);
3592  /*F*/		if (write == (local_read(&tail_page->write) & RB_WRITE_MASK) &&
3625 	event = __rb_page_index(tail_page, tail);
3628 	local_inc(&tail_page->entries);
3635 		tail_page->page->time_stamp = info->ts;
4150 	if (cpu_buffer->tail_page == cpu_buffer->reader_page)
5228 	cpu_buffer->tail_page = cpu_buffer->head_page;
6019 		cpu_buffer->tail_page = cpu_buffer->commit_page = cpu_buffer->head_page;