Merge tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "Nothing major this round.  Mostly small clean ups and fixes.

  Some visible changes:

   - A new flag was added to distinguish traces done in NMI context.

   - Preempt tracer now shows functions where preemption is disabled but
     interrupts are still enabled.

  Other notes:

   - Updates were done to function tracing to allow better performance
     with perf.

   - Infrastructure code has been added to allow for a new histogram
     feature for recording live trace event histograms that can be
     configured by simple user commands.  The feature itself was just
     finished, but needs a round in linux-next before being pulled.

     This only includes some infrastructure changes that will be needed"

* tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits)
  tracing: Record and show NMI state
  tracing: Fix trace_printk() to print when not using bprintk()
  tracing: Remove redundant reset per-CPU buff in irqsoff tracer
  x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c
  tracing: Fix crash from reading trace_pipe with sendfile
  tracing: Have preempt(irqs)off trace preempt disabled functions
  tracing: Fix return while holding a lock in register_tracer()
  ftrace: Use kasprintf() in ftrace_profile_tracefs()
  ftrace: Update dynamic ftrace calls only if necessary
  ftrace: Make ftrace_hash_rec_enable return update bool
  tracing: Fix typoes in code comment and printk in trace_nop.c
  tracing, writeback: Replace cgroup path to cgroup ino
  tracing: Use flags instead of bool in trigger structure
  tracing: Add an unreg_all() callback to trigger commands
  tracing: Add needs_rec flag to event triggers
  tracing: Add a per-event-trigger 'paused' field
  tracing: Add get_syscall_name()
  tracing: Add event record param to trigger_ops.func()
  tracing: Make event trigger functions available
  tracing: Make ftrace_event_field checking functions available
  ...

1 files changed, 7 insertions, 3 deletions

diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 282982195e09..0bb9cf2d53e6 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -389,7 +389,9 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 	char irqs_off;
 	int hardirq;
 	int softirq;
+	int nmi;
 
+	nmi = entry->flags & TRACE_FLAG_NMI;
 	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 
@@ -415,10 +417,12 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 	}
 
 	hardsoft_irq =
+		(nmi && hardirq)     ? 'Z' :
+		nmi                  ? 'z' :
 		(hardirq && softirq) ? 'H' :
-		hardirq ? 'h' :
-		softirq ? 's' :
-		'.';
+		hardirq              ? 'h' :
+		softirq              ? 's' :
+		                       '.' ;
 
 	trace_seq_printf(s, "%c%c%c",
 			 irqs_off, need_resched, hardsoft_irq);