Merge tag 'trace-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "New features for this release:

   - Pretty much a full rewrite of the processing of function plugins.
     i.e. echo do_IRQ:stacktrace > set_ftrace_filter

   - The rewrite was needed to add plugins to be unique to tracing
     instances. i.e. mkdir instance/foo; cd instances/foo; echo
     do_IRQ:stacktrace > set_ftrace_filter The old way was written very
     hacky. This removes a lot of those hacks.

   - New "function-fork" tracing option. When set, pids in the
     set_ftrace_pid will have their children added when the processes
     with their pids listed in the set_ftrace_pid file forks.

   - Exposure of "maxactive" for kretprobe in kprobe_events

   - Allow for builtin init functions to be traced by the function
     tracer (via the kernel command line). Module init function tracing
     will come in the next release.

   - Added more selftests, and have selftests also test in an instance"

* tag 'trace-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (60 commits)
  ring-buffer: Return reader page back into existing ring buffer
  selftests: ftrace: Allow some event trigger tests to run in an instance
  selftests: ftrace: Have some basic tests run in a tracing instance too
  selftests: ftrace: Have event tests also run in an tracing instance
  selftests: ftrace: Make func_event_triggers and func_traceonoff_triggers tests do instances
  selftests: ftrace: Allow some tests to be run in a tracing instance
  tracing/ftrace: Allow for instances to trigger their own stacktrace probes
  tracing/ftrace: Allow for the traceonoff probe be unique to instances
  tracing/ftrace: Enable snapshot function trigger to work with instances
  tracing/ftrace: Allow instances to have their own function probes
  tracing/ftrace: Add a better way to pass data via the probe functions
  ftrace: Dynamically create the probe ftrace_ops for the trace_array
  tracing: Pass the trace_array into ftrace_probe_ops functions
  tracing: Have the trace_array hold the list of registered func probes
  ftrace: If the hash for a probe fails to update then free what was initialized
  ftrace: Have the function probes call their own function
  ftrace: Have each function probe use its own ftrace_ops
  ftrace: Have unregister_ftrace_function_probe_func() return a value
  ftrace: Add helper function ftrace_hash_move_and_update_ops()
  ftrace: Remove data field from ftrace_func_probe structure
  ...

1 files changed, 7 insertions, 3 deletions

diff --git a/init/main.c b/init/main.c
index b1b9dbf7622f..cc48053bb39f 100644
--- a/init/main.c
+++ b/init/main.c
@@ -545,6 +545,11 @@ asmlinkage __visible void __init start_kernel(void)
         trap_init();
         mm_init();
 
+        ftrace_init();
+
+        /* trace_printk can be enabled here */
+        early_trace_init();
+
         /*
          * Set up the scheduler prior starting any interrupts (such as the
          * timer interrupt). Full topology setup happens at smp_init()
@@ -570,7 +575,7 @@ asmlinkage __visible void __init start_kernel(void)
 
         rcu_init();
 
-        /* trace_printk() and trace points may be used after this */
+        /* Trace events are available after this */
         trace_init();
 
         context_tracking_init();
@@ -670,8 +675,6 @@ asmlinkage __visible void __init start_kernel(void)
                 efi_free_boot_services();
         }
 
-        ftrace_init();
-
         /* Do the rest non-__init'ed, we're now alive */
         rest_init();
 }
@@ -959,6 +962,7 @@ static int __ref kernel_init(void *unused)
         kernel_init_freeable();
         /* need to finish all async __init code before freeing the memory */
         async_synchronize_full();
+        ftrace_free_init_mem();
         free_initmem();
         mark_readonly();
         system_state = SYSTEM_RUNNING;