diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h index 7d9eb39fa76a..025159e17e1b 100644 --- a/include/linux/ring_buffer.h +++ b/include/linux/ring_buffer.h @@ -178,6 +178,8 @@ void ring_buffer_normalize_time_stamp(struct ring_buffer *buffer, int cpu, u64 *ts); void ring_buffer_set_clock(struct ring_buffer *buffer, u64 (*clock)(void)); +void ring_buffer_set_time_stamp_abs(struct ring_buffer *buffer, bool abs); +bool ring_buffer_time_stamp_abs(struct ring_buffer *buffer); size_t ring_buffer_page_len(void *page); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index dcf1c4dd3efe..2a03e069bbc6 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -488,6 +488,7 @@ struct ring_buffer { u64 (*clock)(void); struct rb_irq_work irq_work; + bool time_stamp_abs; }; struct ring_buffer_iter { @@ -1382,6 +1383,16 @@ void ring_buffer_set_clock(struct ring_buffer *buffer, buffer->clock = clock; } +void ring_buffer_set_time_stamp_abs(struct ring_buffer *buffer, bool abs) +{ + buffer->time_stamp_abs = abs; +} + +bool ring_buffer_time_stamp_abs(struct ring_buffer *buffer) +{ + return buffer->time_stamp_abs; +} + static void rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer); static inline unsigned long rb_page_entries(struct buffer_page *bpage) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 20a2300ae4e8..cba003f0362e 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2269,7 +2269,7 @@ trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, *current_rb = trace_file->tr->trace_buffer.buffer; - if ((trace_file->flags & + if (!ring_buffer_time_stamp_abs(*current_rb) && (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && (entry = this_cpu_read(trace_buffered_event))) { /* Try to use the per cpu buffer first */ @@ -6282,6 +6282,37 @@ static int tracing_clock_open(struct inode *inode, struct file *file) return ret; } +int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs) +{ + int ret = 0; + + mutex_lock(&trace_types_lock); + + if (abs && tr->time_stamp_abs_ref++) + goto out; + + if (!abs) { + if (WARN_ON_ONCE(!tr->time_stamp_abs_ref)) { + ret = -EINVAL; + goto out; + } + + if (--tr->time_stamp_abs_ref) + goto out; + } + + ring_buffer_set_time_stamp_abs(tr->trace_buffer.buffer, abs); + +#ifdef CONFIG_TRACER_MAX_TRACE + if (tr->max_buffer.buffer) + ring_buffer_set_time_stamp_abs(tr->max_buffer.buffer, abs); +#endif + out: + mutex_unlock(&trace_types_lock); + + return ret; +} + struct ftrace_buffer_info { struct trace_iterator iter; void *spare; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 2a6d0325a761..477341710ebf 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -273,6 +273,7 @@ struct trace_array { /* function tracing enabled */ int function_enabled; #endif + int time_stamp_abs_ref; }; enum { @@ -286,6 +287,8 @@ extern struct mutex trace_types_lock; extern int trace_array_get(struct trace_array *tr); extern void trace_array_put(struct trace_array *tr); +extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs); + /* * The global tracer (top) should be the first trace array added, * but we check the flag anyway.