Merge tag 'trace-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - simplify the Kconfig use of FTRACE and TRACE_IRQFLAGS_SUPPORT

 - bootconfig can now start histograms

 - bootconfig supports group/all enabling

 - histograms now can put values in linear size buckets

 - execnames can be passed to synthetic events

 - introduce "event probes" that attach to other events and can retrieve
   data from pointers of fields, or record fields as different types (a
   pointer to a string as a string instead of just a hex number)

 - various fixes and clean ups

* tag 'trace-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (35 commits)
  tracing/doc: Fix table format in histogram code
  selftests/ftrace: Add selftest for testing duplicate eprobes and kprobes
  selftests/ftrace: Add selftest for testing eprobe events on synthetic events
  selftests/ftrace: Add test case to test adding and removing of event probe
  selftests/ftrace: Fix requirement check of README file
  selftests/ftrace: Add clear_dynamic_events() to test cases
  tracing: Add a probe that attaches to trace events
  tracing/probes: Reject events which have the same name of existing one
  tracing/probes: Have process_fetch_insn() take a void * instead of pt_regs
  tracing/probe: Change traceprobe_set_print_fmt() to take a type
  tracing/probes: Use struct_size() instead of defining custom macros
  tracing/probes: Allow for dot delimiter as well as slash for system names
  tracing/probe: Have traceprobe_parse_probe_arg() take a const arg
  tracing: Have dynamic events have a ref counter
  tracing: Add DYNAMIC flag for dynamic events
  tracing: Replace deprecated CPU-hotplug functions.
  MAINTAINERS: Add an entry for os noise/latency
  tracepoint: Fix kerneldoc comments
  bootconfig/tracing/ktest: Update ktest example for boot-time tracing
  tools/bootconfig: Use per-group/all enable option in ftrace2bconf script
  ...

1 files changed, 80 insertions, 5 deletions

diff --git a/Documentation/trace/boottime-trace.rst b/Documentation/trace/boottime-trace.rst
index 8053898cfeb4..6dcfbc64014d 100644
--- a/Documentation/trace/boottime-trace.rst
+++ b/Documentation/trace/boottime-trace.rst
@@ -125,6 +125,71 @@ Note that kprobe and synthetic event definitions can be written under
 instance node, but those are also visible from other instances. So please
 take care for event name conflict.
 
+Ftrace Histogram Options
+------------------------
+
+Since it is too long to write a histogram action as a string for per-event
+action option, there are tree-style options under per-event 'hist' subkey
+for the histogram actions. For the detail of the each parameter,
+please read the event histogram document [3]_.
+
+.. [3] See :ref:`Documentation/trace/histogram.rst <histogram>`
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]keys = KEY1[, KEY2[...]]
+  Set histogram key parameters. (Mandatory)
+  The 'N' is a digit string for the multiple histogram. You can omit it
+  if there is one histogram on the event.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]values = VAL1[, VAL2[...]]
+  Set histogram value parameters.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]sort = SORT1[, SORT2[...]]
+  Set histogram sort parameter options.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]size = NR_ENTRIES
+  Set histogram size (number of entries).
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]name = NAME
+  Set histogram name.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]var.VARIABLE = EXPR
+  Define a new VARIABLE by EXPR expression.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]<pause|continue|clear>
+  Set histogram control parameter. You can set one of them.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onmatch.[M.]event = GROUP.EVENT
+  Set histogram 'onmatch' handler matching event parameter.
+  The 'M' is a digit string for the multiple 'onmatch' handler. You can omit it
+  if there is one 'onmatch' handler on this histogram.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onmatch.[M.]trace = EVENT[, ARG1[...]]
+  Set histogram 'trace' action for 'onmatch'.
+  EVENT must be a synthetic event name, and ARG1... are parameters
+  for that event. Mandatory if 'onmatch.event' option is set.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onmax.[M.]var = VAR
+  Set histogram 'onmax' handler variable parameter.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onchange.[M.]var = VAR
+  Set histogram 'onchange' handler variable parameter.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]<onmax|onchange>.[M.]save = ARG1[, ARG2[...]]
+  Set histogram 'save' action parameters for 'onmax' or 'onchange' handler.
+  This option or below 'snapshot' option is mandatory if 'onmax.var' or
+  'onchange.var' option is set.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]<onmax|onchange>.[M.]snapshot
+  Set histogram 'snapshot' action for 'onmax' or 'onchange' handler.
+  This option or above 'save' option is mandatory if 'onmax.var' or
+  'onchange.var' option is set.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.filter = FILTER_EXPR
+  Set histogram filter expression. You don't need 'if' in the FILTER_EXPR.
+
+Note that this 'hist' option can conflict with the per-event 'actions'
+option if the 'actions' option has a histogram action.
+
 
 When to Start
 =============
@@ -159,13 +224,23 @@ below::
         }
         synthetic.initcall_latency {
                 fields = "unsigned long func", "u64 lat"
-                actions = "hist:keys=func.sym,lat:vals=lat:sort=lat"
+                hist {
+                        keys = func.sym, lat
+                        values = lat
+                        sort = lat
+                }
         }
-        initcall.initcall_start {
-                actions = "hist:keys=func:ts0=common_timestamp.usecs"
+        initcall.initcall_start.hist {
+                keys = func
+                var.ts0 = common_timestamp.usecs
         }
-        initcall.initcall_finish {
-                actions = "hist:keys=func:lat=common_timestamp.usecs-$ts0:onmatch(initcall.initcall_start).initcall_latency(func,$lat)"
+        initcall.initcall_finish.hist {
+                keys = func
+                var.lat = common_timestamp.usecs - $ts0
+                onmatch {
+                        event = initcall.initcall_start
+                        trace = initcall_latency, func, $lat
+                }
         }
   }