From: Steven Rostedt The trace_pipe did not recognize the latency format flag and would produce different output than the trace file. The problem was partly due that the trace flags in the iterator was not set as well as the trace_pipe zeros out part of the iterator (including the flags) to be able to use the same routines as the trace file. trace_flags of the iterator should not cause any problems when not zeroed out by for trace_pipe. Reported-by: Johannes Berg Signed-off-by: Steven Rostedt --- include/linux/ftrace_event.h | 2 +- kernel/trace/trace.c | 3 +++ 2 files changed, 4 insertions(+), 1 deletions(-) diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index bbf40f6..5c093ff 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -51,6 +51,7 @@ struct trace_iterator { int cpu_file; struct mutex mutex; struct ring_buffer_iter *buffer_iter[NR_CPUS]; + unsigned long iter_flags; /* The below is zeroed out in pipe_read */ struct trace_seq seq; @@ -58,7 +59,6 @@ struct trace_iterator { int cpu; u64 ts; - unsigned long iter_flags; loff_t pos; long idx; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a3a8a87..cae34c6 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2826,6 +2826,9 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) /* trace pipe does not show start of buffer */ cpumask_setall(iter->started); + if (trace_flags & TRACE_ITER_LATENCY_FMT) + iter->iter_flags |= TRACE_FILE_LAT_FMT; + iter->cpu_file = cpu_file; iter->tr = &global_trace; mutex_init(&iter->mutex); -- 1.6.3.1 -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/