diff options
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/ring_buffer.c | 40 |
1 files changed, 22 insertions, 18 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 026238c55b0c..7ee6619951ea 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -422,13 +422,15 @@ struct rb_event_info { /* * Used for the add_timestamp * NONE - * NORMAL - may be for either time extend or absolute + * EXTEND - wants a time extend + * ABSOLUTE - the buffer requests all events to have absolute time stamps * FORCE - force a full time stamp. */ enum { - RB_ADD_STAMP_NONE, - RB_ADD_STAMP_NORMAL, - RB_ADD_STAMP_FORCE + RB_ADD_STAMP_NONE = 0, + RB_ADD_STAMP_EXTEND = BIT(1), + RB_ADD_STAMP_ABSOLUTE = BIT(2), + RB_ADD_STAMP_FORCE = BIT(3) }; /* * Used for which event context the event is in. @@ -2434,8 +2436,8 @@ rb_update_event(struct ring_buffer_per_cpu *cpu_buffer, * add it to the start of the reserved space. */ if (unlikely(info->add_timestamp)) { - bool abs = info->add_timestamp == RB_ADD_STAMP_FORCE || - ring_buffer_time_stamp_abs(cpu_buffer->buffer); + bool abs = info->add_timestamp & + (RB_ADD_STAMP_FORCE | RB_ADD_STAMP_ABSOLUTE); event = rb_add_time_stamp(event, abs ? info->delta : delta, abs); length -= RB_LEN_TIME_EXTEND; @@ -2884,8 +2886,8 @@ int ring_buffer_unlock_commit(struct trace_buffer *buffer, EXPORT_SYMBOL_GPL(ring_buffer_unlock_commit); static noinline void -rb_handle_timestamp(struct ring_buffer_per_cpu *cpu_buffer, - struct rb_event_info *info) +rb_check_timestamp(struct ring_buffer_per_cpu *cpu_buffer, + struct rb_event_info *info) { WARN_ONCE(info->delta > (1ULL << 59), KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n%s", @@ -2897,7 +2899,6 @@ rb_handle_timestamp(struct ring_buffer_per_cpu *cpu_buffer, "please switch to the trace global clock:\n" " echo global > /sys/kernel/debug/tracing/trace_clock\n" "or add trace_clock=global to the kernel command line\n"); - info->add_timestamp = RB_ADD_STAMP_NORMAL; } static struct ring_buffer_event * @@ -2908,7 +2909,6 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer, struct buffer_page *tail_page; unsigned long tail, write, w; u64 before, after; - bool abs = false; /* Don't let the compiler play games with cpu_buffer->tail_page */ tail_page = info->tail_page = READ_ONCE(cpu_buffer->tail_page); @@ -2922,20 +2922,23 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer, if (ring_buffer_time_stamp_abs(cpu_buffer->buffer)) { info->delta = info->ts; - abs = true; + info->add_timestamp = RB_ADD_STAMP_ABSOLUTE; } else { info->delta = info->ts - after; } - if (unlikely(test_time_stamp(info->delta))) - rb_handle_timestamp(cpu_buffer, info); + if (unlikely(test_time_stamp(info->delta))) { + rb_check_timestamp(cpu_buffer, info); + info->add_timestamp |= RB_ADD_STAMP_EXTEND; + } /* * If interrupting an event time update, we may need an absolute timestamp. * Don't bother if this is the start of a new page (w == 0). */ if (unlikely(before != after && w)) - info->add_timestamp = RB_ADD_STAMP_FORCE; + info->add_timestamp |= RB_ADD_STAMP_FORCE | RB_ADD_STAMP_EXTEND; + /* * If the time delta since the last event is too big to * hold in the time field of the event, then we append a @@ -2972,7 +2975,8 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer, /*D*/ local64_set(&cpu_buffer->write_stamp, info->ts); barrier(); /*E*/ save_before = local64_read(&cpu_buffer->before_stamp); - if (likely(info->add_timestamp != RB_ADD_STAMP_FORCE)) + if (likely(!(info->add_timestamp & + (RB_ADD_STAMP_FORCE | RB_ADD_STAMP_ABSOLUTE)))) /* This did not interrupt any time update */ info->delta = info->ts - after; else @@ -3015,15 +3019,15 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer, */ info->delta = 0; } - if (info->add_timestamp == RB_ADD_STAMP_FORCE) - info->add_timestamp = RB_ADD_STAMP_NORMAL; + info->add_timestamp &= ~RB_ADD_STAMP_FORCE; } /* * If this is the first commit on the page, then it has the same * timestamp as the page itself. */ - if (unlikely(!tail && info->add_timestamp != RB_ADD_STAMP_FORCE && !abs)) + if (unlikely(!tail && !(info->add_timestamp & + (RB_ADD_STAMP_FORCE | RB_ADD_STAMP_ABSOLUTE)))) info->delta = 0; /* We reserved something on the buffer */ |