Merge tag 'trace-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/g…

…it/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "This is mostly clean ups and small fixes.  Some of the more visible
  changes are:

   - The function pid code uses the event pid filtering logic
   - [ku]probe events have access to current->comm
   - trace_printk now has sample code
   - PCI devices now trace physical addresses
   - stack tracing has less unnessary functions traced"

* tag 'trace-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  printk, tracing: Avoiding unneeded blank lines
  tracing: Use __get_str() when manipulating strings
  tracing, RAS: Cleanup on __get_str() usage
  tracing: Use outer () on __get_str() definition
  ftrace: Reduce size of function graph entries
  tracing: Have HIST_TRIGGERS select TRACING
  tracing: Using for_each_set_bit() to simplify trace_pid_write()
  ftrace: Move toplevel init out of ftrace_init_tracefs()
  tracing/function_graph: Fix filters for function_graph threshold
  tracing: Skip more functions when doing stack tracing of events
  tracing: Expose CPU physical addresses (resource values) for PCI devices
  tracing: Show the preempt count of when the event was called
  tracing: Add trace_printk sample code
  tracing: Choose static tp_printk buffer by explicit nesting count
  tracing: expose current->comm to [ku]probe events
  ftrace: Have set_ftrace_pid use the bitmap like events do
  tracing: Move pid_list write processing into its own function
  tracing: Move the pid_list seq_file functions to be global
  tracing: Move filtered_pid helper functions into trace.c
  tracing: Make the pid filtering helper functions global

Documentation/trace/kprobetrace.txt

@@ -40,6 +40,7 @@ Synopsis of kprobe_events
   $stackN	: Fetch Nth entry of stack (N >= 0)
   $stack	: Fetch stack address.
   $retval	: Fetch return value.(*)
+  $comm		: Fetch current task comm.
   +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
   NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
   FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
@@ -62,6 +63,8 @@ offset, and container-size (usually 32). The syntax is;
 
  b<bit-width>@<bit-offset>/<container-size>
 
+For $comm, the default type is "string"; any other type is invalid.
+
 
 Per-Probe Event Filtering
 -------------------------

Documentation/trace/uprobetracer.txt

@@ -36,6 +36,7 @@ Synopsis of uprobe_tracer
    $stackN	: Fetch Nth entry of stack (N >= 0)
    $stack	: Fetch stack address.
    $retval	: Fetch return value.(*)
+   $comm	: Fetch current task comm.
    +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
    NAME=FETCHARG     : Set NAME as the argument name of FETCHARG.
    FETCHARG:TYPE     : Set TYPE as the type of FETCHARG. Currently, basic types
@@ -57,6 +58,8 @@ offset, and container-size (usually 32). The syntax is;
 
  b<bit-width>@<bit-offset>/<container-size>
 
+For $comm, the default type is "string"; any other type is invalid.
+
 
 Event Profiling
 ---------------

fs/nfs/nfs4trace.h

@@ -1235,8 +1235,8 @@ DECLARE_EVENT_CLASS(nfs4_idmap_event,
 				len = 0;
 			__entry->error = error < 0 ? error : 0;
 			__entry->id = id;
-			memcpy(__get_dynamic_array(name), name, len);
-			((char *)__get_dynamic_array(name))[len] = 0;
+			memcpy(__get_str(name), name, len);
+			__get_str(name)[len] = 0;
 		),
 
 		TP_printk(

fs/nfs/nfstrace.h

@@ -707,9 +707,9 @@ TRACE_EVENT(nfs_sillyrename_unlink,
 			__entry->dev = dir->i_sb->s_dev;
 			__entry->dir = NFS_FILEID(dir);
 			__entry->error = error;
-			memcpy(__get_dynamic_array(name),
+			memcpy(__get_str(name),
 				data->args.name.name, len);
-			((char *)__get_dynamic_array(name))[len] = 0;
+			__get_str(name)[len] = 0;
 		),
 
 		TP_printk(

include/linux/ftrace.h

@@ -754,23 +754,27 @@ static inline void ftrace_init(void) { }
 
 /*
  * Structure that defines an entry function trace.
+ * It's already packed but the attribute "packed" is needed
+ * to remove extra padding at the end.
  */
 struct ftrace_graph_ent {
 	unsigned long func; /* Current function */
 	int depth;
-};
+} __packed;
 
 /*
  * Structure that defines a return function trace.
+ * It's already packed but the attribute "packed" is needed
+ * to remove extra padding at the end.
  */
 struct ftrace_graph_ret {
 	unsigned long func; /* Current function */
-	unsigned long long calltime;
-	unsigned long long rettime;
 	/* Number of functions that overran the depth limit for current task */
 	unsigned long overrun;
+	unsigned long long calltime;
+	unsigned long long rettime;
 	int depth;
-};
+} __packed;
 
 /* Type of the callback handlers for tracing function graph*/
 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */

include/ras/ras_event.h

@@ -147,7 +147,7 @@ TRACE_EVENT(mc_event,
 		  __entry->error_count,
 		  mc_event_error_type(__entry->error_type),
 		  __entry->error_count > 1 ? "s" : "",
-		  ((char *)__get_str(msg))[0] ? " " : "",
+		  __get_str(msg)[0] ? " " : "",
 		  __get_str(msg),
 		  __get_str(label),
 		  __entry->mc_index,
@@ -157,7 +157,7 @@ TRACE_EVENT(mc_event,
 		  __entry->address,
 		  1 << __entry->grain_bits,
 		  __entry->syndrome,
-		  ((char *)__get_str(driver_detail))[0] ? " " : "",
+		  __get_str(driver_detail)[0] ? " " : "",
 		  __get_str(driver_detail))
 );
 

include/trace/events/printk.h

@@ -16,8 +16,16 @@ TRACE_EVENT(console,
 	),
 
 	TP_fast_assign(
-		memcpy(__get_dynamic_array(msg), text, len);
-		((char *)__get_dynamic_array(msg))[len] = 0;
+		/*
+		 * Each trace entry is printed in a new line.
+		 * If the msg finishes with '\n', cut it off
+		 * to avoid blank lines in the trace.
+		 */
+		if ((len > 0) && (text[len-1] == '\n'))
+			len -= 1;
+
+		memcpy(__get_str(msg), text, len);
+		__get_str(msg)[len] = 0;
 	),
 
 	TP_printk("%s", __get_str(msg))

include/trace/perf.h

@@ -15,7 +15,7 @@
 		((__entry->__data_loc_##field >> 16) & 0xffff)
 
 #undef __get_str
-#define __get_str(field) (char *)__get_dynamic_array(field)
+#define __get_str(field) ((char *)__get_dynamic_array(field))
 
 #undef __get_bitmask
 #define __get_bitmask(field) (char *)__get_dynamic_array(field)

include/trace/trace_events.h

@@ -256,7 +256,7 @@ TRACE_MAKE_SYSTEM_STR();
 		((__entry->__data_loc_##field >> 16) & 0xffff)
 
 #undef __get_str
-#define __get_str(field) (char *)__get_dynamic_array(field)
+#define __get_str(field) ((char *)__get_dynamic_array(field))
 
 #undef __get_bitmask
 #define __get_bitmask(field)						\

kernel/trace/Kconfig

@@ -542,6 +542,7 @@ config HIST_TRIGGERS
 	bool "Histogram triggers"
 	depends on ARCH_HAVE_NMI_SAFE_CMPXCHG
 	select TRACING_MAP
+	select TRACING
 	default n
 	help
 	  Hist triggers allow one or more arbitrary trace event fields