--- kernel/trace/ring_buffer.c

+++ kernel/trace/ring_buffer.c

@@ -389,7 +389,7 @@ static inline int test_time_stamp(u64 de

#define BUF_MAX_DATA_SIZE (BUF_PAGE_SIZE - (sizeof(u32) * 2))

/* Max number of timestamps that can fit on a page */

-#define RB_TIMESTAMPS_PER_PAGE (BUF_PAGE_SIZE / RB_LEN_TIME_STAMP)

+#define RB_TIMESTAMPS_PER_PAGE (BUF_PAGE_SIZE / RB_LEN_TIME_EXTEND)

int ring_buffer_print_page_header(struct trace_seq *s)

{

@@ -2237,12 +2237,12 @@ ring_buffer_lock_reserve(struct ring_buf

if (ring_buffer_flags != RB_BUFFERS_ON)

return NULL;

- if (atomic_read(&buffer->record_disabled))

- return NULL;

-

/* If we are tracing schedule, we don't want to recurse */

resched = ftrace_preempt_disable();

+ if (atomic_read(&buffer->record_disabled))

+ goto out_nocheck;

+

if (trace_recursive_lock())

goto out_nocheck;

@@ -2474,11 +2474,11 @@ int ring_buffer_write(struct ring_buffer

if (ring_buffer_flags != RB_BUFFERS_ON)

return -EBUSY;

- if (atomic_read(&buffer->record_disabled))

- return -EBUSY;

-

resched = ftrace_preempt_disable();

+ if (atomic_read(&buffer->record_disabled))

+ goto out;

+

cpu = raw_smp_processor_id();

if (!cpumask_test_cpu(cpu, buffer->cpumask))