[RFC][PATCH 08/11] ring-buffer: Do not disable recording when there is an iterator

From: Steven Rostedt
Date: Tue Mar 17 2020 - 17:35:24 EST


From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>

Now that the iterator can handle a concurrent writer, do not disable writing
to the ring buffer when there is an iterator present.

Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
kernel/trace/ring_buffer.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 5979327254f9..8bafba674ec0 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -4295,7 +4295,6 @@ ring_buffer_read_prepare(struct trace_buffer *buffer, int cpu, gfp_t flags)
iter->cpu_buffer = cpu_buffer;

atomic_inc(&buffer->resize_disabled);
- atomic_inc(&cpu_buffer->record_disabled);

return iter;
}
@@ -4368,7 +4367,6 @@ ring_buffer_read_finish(struct ring_buffer_iter *iter)
rb_check_pages(cpu_buffer);
raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);

- atomic_dec(&cpu_buffer->record_disabled);
atomic_dec(&cpu_buffer->buffer->resize_disabled);
kfree(iter->event);
kfree(iter);
--
2.25.1