diff options
| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-04-10 08:56:59 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-04-10 08:56:59 +0200 |
| commit | 8e86652e3e7152bba80c3b4d03814e40ede1abc7 (patch) | |
| tree | 1b31b94957fba52d8d223d03388b9afd8b522ad6 /kernel/trace/ring_buffer.c | |
| parent | 0246b15bbb43404d8d6f0ec86121c05515e0ed0b (diff) | |
| parent | 09a9639e56c01c7a00d6c0ca63f4c7c41abe075d (diff) | |
Merge 6.3-rc6 into usb-next
We need the USB fixes in here for testing, and this resolves two merge
conflicts, one pointed out by linux-next:
drivers/usb/dwc3/dwc3-pci.c
drivers/usb/host/xhci-pci.c
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/trace/ring_buffer.c')
| -rw-r--r-- | kernel/trace/ring_buffer.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index c6f47b6cfd5f..76a2d91eecad 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -3098,6 +3098,10 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer) if (RB_WARN_ON(cpu_buffer, rb_is_reader_page(cpu_buffer->tail_page))) return; + /* + * No need for a memory barrier here, as the update + * of the tail_page did it for this page. + */ local_set(&cpu_buffer->commit_page->page->commit, rb_page_write(cpu_buffer->commit_page)); rb_inc_page(&cpu_buffer->commit_page); @@ -3107,6 +3111,8 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer) while (rb_commit_index(cpu_buffer) != rb_page_write(cpu_buffer->commit_page)) { + /* Make sure the readers see the content of what is committed. */ + smp_wmb(); local_set(&cpu_buffer->commit_page->page->commit, rb_page_write(cpu_buffer->commit_page)); RB_WARN_ON(cpu_buffer, @@ -4684,7 +4690,12 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer) /* * Make sure we see any padding after the write update - * (see rb_reset_tail()) + * (see rb_reset_tail()). + * + * In addition, a writer may be writing on the reader page + * if the page has not been fully filled, so the read barrier + * is also needed to make sure we see the content of what is + * committed by the writer (see rb_set_commit_to_write()). */ smp_rmb(); |