Merge tag 'trace-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The major changes in this tracing update includes:

   - Removal of non-DYNAMIC_FTRACE from 32bit x86

   - Removal of mcount support from x86

   - Emulating a call from int3 on x86_64, fixes live kernel patching

   - Consolidated Tracing Error logs file

  Minor updates:

   - Removal of klp_check_compiler_support()

   - kdb ftrace dumping output changes

   - Accessing and creating ftrace instances from inside the kernel

   - Clean up of #define if macro

   - Introduction of TRACE_EVENT_NOP() to disable trace events based on
     config options

  And other minor fixes and clean ups"

* tag 'trace-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
  x86: Hide the int3_emulate_call/jmp functions from UML
  livepatch: Remove klp_check_compiler_support()
  ftrace/x86: Remove mcount support
  ftrace/x86_32: Remove support for non DYNAMIC_FTRACE
  tracing: Simplify "if" macro code
  tracing: Fix documentation about disabling options using trace_options
  tracing: Replace kzalloc with kcalloc
  tracing: Fix partial reading of trace event's id file
  tracing: Allow RCU to run between postponed startup tests
  tracing: Fix white space issues in parse_pred() function
  tracing: Eliminate const char[] auto variables
  ring-buffer: Fix mispelling of Calculate
  tracing: probeevent: Fix to make the type of $comm string
  tracing: probeevent: Do not accumulate on ret variable
  tracing: uprobes: Re-enable $comm support for uprobe events
  ftrace/x86_64: Emulate call function while updating in breakpoint handler
  x86_64: Allow breakpoints to emulate call instructions
  x86_64: Add gap to int3 to allow for call emulation
  tracing: kdb: Allow ftdump to skip all but the last few entries
  tracing: Add trace_total_entries() / trace_total_entries_cpu()
  ...

3 files changed, 35 insertions, 17 deletions

diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index d58aa0db05f9..8aaf7cd026b0 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -53,23 +53,24 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
  * "Define 'is'", Bill Clinton
  * "Define 'if'", Steven Rostedt
  */
-#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
-#define __trace_if(cond) \
-	if (__builtin_constant_p(!!(cond)) ? !!(cond) :			\
-	({								\
-		int ______r;						\
-		static struct ftrace_branch_data			\
-			__aligned(4)					\
-			__section("_ftrace_branch")			\
-			______f = {					\
-				.func = __func__,			\
-				.file = __FILE__,			\
-				.line = __LINE__,			\
-			};						\
-		______r = !!(cond);					\
-		______r ? ______f.miss_hit[1]++ : ______f.miss_hit[0]++;\
-		______r;						\
-	}))
+#define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
+
+#define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
+
+#define __trace_if_value(cond) ({			\
+	static struct ftrace_branch_data		\
+		__aligned(4)				\
+		__section("_ftrace_branch")		\
+		__if_trace = {				\
+			.func = __func__,		\
+			.file = __FILE__,		\
+			.line = __LINE__,		\
+		};					\
+	(cond) ?					\
+		(__if_trace.miss_hit[1]++,1) :		\
+		(__if_trace.miss_hit[0]++,0);		\
+})
+
 #endif /* CONFIG_PROFILE_ALL_BRANCHES */
 
 #else
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 20899919ead8..25e2995d4a4c 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -741,6 +741,8 @@ struct ftrace_graph_ret {
 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
 
+extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace);
+
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 
 struct fgraph_ops {
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 9c3186578ce0..86b019aa2839 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -548,4 +548,19 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p)
 
 #define TRACE_EVENT_PERF_PERM(event, expr...)
 
+#define DECLARE_EVENT_NOP(name, proto, args)				\
+	static inline void trace_##name(proto)				\
+	{ }								\
+	static inline bool trace_##name##_enabled(void)			\
+	{								\
+		return false;						\
+	}
+
+#define TRACE_EVENT_NOP(name, proto, args, struct, assign, print)	\
+	DECLARE_EVENT_NOP(name, PARAMS(proto), PARAMS(args))
+
+#define DECLARE_EVENT_CLASS_NOP(name, proto, args, tstruct, assign, print)
+#define DEFINE_EVENT_NOP(template, name, proto, args)			\
+	DECLARE_EVENT_NOP(name, PARAMS(proto), PARAMS(args))
+
 #endif /* ifdef TRACE_EVENT (see note above) */