mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-24 13:13:57 +08:00
ring_buffer: fix typing mistake
Impact: Fix bug I found several very very curious line. It's so curious that it may be brought by typing mistake. When (cpu_buffer->reader_page == cpu_buffer->commit_page): 1) We haven't copied it for bpage is changed: bpage = cpu_buffer->reader_page->page; memcpy(bpage->data, cpu_buffer->reader_page->page->data + read ... ) 2) We need update cpu_buffer->reader_page->read, but "cpu_buffer->reader_page += read;" is not right. [ This bug was a typo. The commit->reader_page is a page pointer and not an index into the page. The line should have been commit->reader_page->read += read. The other changes by Lai are nice clean ups to the code. - SDR ] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This commit is contained in:
parent
34cd4998d3
commit
b85fa01ed9
@ -2406,7 +2406,7 @@ void ring_buffer_free_read_page(struct ring_buffer *buffer, void *data)
|
||||
* to swap with a page in the ring buffer.
|
||||
*
|
||||
* for example:
|
||||
* rpage = ring_buffer_alloc_page(buffer);
|
||||
* rpage = ring_buffer_alloc_read_page(buffer);
|
||||
* if (!rpage)
|
||||
* return error;
|
||||
* ret = ring_buffer_read_page(buffer, &rpage, cpu, 0);
|
||||
@ -2461,18 +2461,17 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
|
||||
*/
|
||||
if (cpu_buffer->reader_page == cpu_buffer->commit_page) {
|
||||
unsigned int read = cpu_buffer->reader_page->read;
|
||||
unsigned int commit = rb_page_commit(cpu_buffer->reader_page);
|
||||
|
||||
if (full)
|
||||
goto out;
|
||||
/* The writer is still on the reader page, we must copy */
|
||||
bpage = cpu_buffer->reader_page->page;
|
||||
memcpy(bpage->data,
|
||||
cpu_buffer->reader_page->page->data + read,
|
||||
local_read(&bpage->commit) - read);
|
||||
commit - read);
|
||||
|
||||
/* consume what was read */
|
||||
cpu_buffer->reader_page += read;
|
||||
|
||||
cpu_buffer->reader_page->read = commit;
|
||||
} else {
|
||||
/* swap the pages */
|
||||
rb_init_page(bpage);
|
||||
|
Loading…
Reference in New Issue
Block a user