Merge tag 'trace-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - Add function names as a way to filter function addresses

 - Add sample module to test ftrace ops and dynamic trampolines

 - Allow stack traces to be passed from beginning event to end event for
   synthetic events. This will allow seeing the stack trace of when a
   task is scheduled out and recorded when it gets scheduled back in.

 - Add trace event helper __get_buf() to use as a temporary buffer when
   printing out trace event output.

 - Add kernel command line to create trace instances on boot up.

 - Add enabling of events to instances created at boot up.

 - Add trace_array_puts() to write into instances.

 - Allow boot instances to take a snapshot at the end of boot up.

 - Allow live patch modules to include trace events

 - Minor fixes and clean ups

* tag 'trace-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (31 commits)
  tracing: Remove unnecessary NULL assignment
  tracepoint: Allow livepatch module add trace event
  tracing: Always use canonical ftrace path
  tracing/histogram: Fix stacktrace histogram Documententation
  tracing/histogram: Fix stacktrace key
  tracing/histogram: Fix a few problems with stacktrace variable printing
  tracing: Add BUILD_BUG() to make sure stacktrace fits in strings
  tracing/histogram: Don't use strlen to find length of stacktrace variables
  tracing: Allow boot instances to have snapshot buffers
  tracing: Add trace_array_puts() to write into instance
  tracing: Add enabling of events to boot instances
  tracing: Add creation of instances at boot command line
  tracing: Fix trace_event_raw_event_synth() if else statement
  samples: ftrace: Make some global variables static
  ftrace: sample: avoid open-coded 64-bit division
  samples: ftrace: Include the nospec-branch.h only for x86
  tracing: Acquire buffer from temparary trace sequence
  tracing/histogram: Wrap remaining shell snippets in code blocks
  tracing/osnoise: No need for schedule_hrtimeout range
  bpf/tracing: Use stage6 of tracing to not duplicate macros
  ...

1 files changed, 12 insertions, 0 deletions

diff --git a/Documentation/trace/events.rst b/Documentation/trace/events.rst
index 8b33850b8bf9..f5fcb8e1218f 100644
--- a/Documentation/trace/events.rst
+++ b/Documentation/trace/events.rst
@@ -207,6 +207,18 @@ field name::
 As the kernel will have to know how to retrieve the memory that the pointer
 is at from user space.
 
+You can convert any long type to a function address and search by function name::
+
+  call_site.function == security_prepare_creds
+
+The above will filter when the field "call_site" falls on the address within
+"security_prepare_creds". That is, it will compare the value of "call_site" and
+the filter will return true if it is greater than or equal to the start of
+the function "security_prepare_creds" and less than the end of that function.
+
+The ".function" postfix can only be attached to values of size long, and can only
+be compared with "==" or "!=".
+
 5.2 Setting filters
 -------------------