diff options
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/ring_buffer.c | 61 |
1 files changed, 0 insertions, 61 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index e9420fdc7409..0fc5add6423b 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -115,63 +115,11 @@ int ring_buffer_print_entry_header(struct trace_seq *s) * */ -/* - * A fast way to enable or disable all ring buffers is to - * call tracing_on or tracing_off. Turning off the ring buffers - * prevents all ring buffers from being recorded to. - * Turning this switch on, makes it OK to write to the - * ring buffer, if the ring buffer is enabled itself. - * - * There's three layers that must be on in order to write - * to the ring buffer. - * - * 1) This global flag must be set. - * 2) The ring buffer must be enabled for recording. - * 3) The per cpu buffer must be enabled for recording. - * - * In case of an anomaly, this global flag has a bit set that - * will permantly disable all ring buffers. - */ - -/* - * Global flag to disable all recording to ring buffers - * This has two bits: ON, DISABLED - * - * ON DISABLED - * ---- ---------- - * 0 0 : ring buffers are off - * 1 0 : ring buffers are on - * X 1 : ring buffers are permanently disabled - */ - -enum { - RB_BUFFERS_ON_BIT = 0, - RB_BUFFERS_DISABLED_BIT = 1, -}; - -enum { - RB_BUFFERS_ON = 1 << RB_BUFFERS_ON_BIT, - RB_BUFFERS_DISABLED = 1 << RB_BUFFERS_DISABLED_BIT, -}; - -static unsigned long ring_buffer_flags __read_mostly = RB_BUFFERS_ON; - /* Used for individual buffers (after the counter) */ #define RB_BUFFER_OFF (1 << 20) #define BUF_PAGE_HDR_SIZE offsetof(struct buffer_data_page, data) -/** - * tracing_off_permanent - permanently disable ring buffers - * - * This function, once called, will disable all ring buffers - * permanently. - */ -void tracing_off_permanent(void) -{ - set_bit(RB_BUFFERS_DISABLED_BIT, &ring_buffer_flags); -} - #define RB_EVNT_HDR_SIZE (offsetof(struct ring_buffer_event, array)) #define RB_ALIGNMENT 4U #define RB_MAX_SMALL_DATA (RB_ALIGNMENT * RINGBUF_TYPE_DATA_TYPE_LEN_MAX) @@ -2728,9 +2676,6 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, unsigned long length) struct ring_buffer_event *event; int cpu; - if (ring_buffer_flags != RB_BUFFERS_ON) - return NULL; - /* If we are tracing schedule, we don't want to recurse */ preempt_disable_notrace(); @@ -2992,9 +2937,6 @@ int ring_buffer_write(struct ring_buffer *buffer, int ret = -EBUSY; int cpu; - if (ring_buffer_flags != RB_BUFFERS_ON) - return -EBUSY; - preempt_disable_notrace(); if (atomic_read(&buffer->record_disabled)) @@ -4350,9 +4292,6 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a, ret = -EAGAIN; - if (ring_buffer_flags != RB_BUFFERS_ON) - goto out; - if (atomic_read(&buffer_a->record_disabled)) goto out; |