[GIT PULL] tracing: Updates for v7.1

[Steven Rostedt]

Linus,

*** NOTE ***
This has a conflict with your current tree. I did a merge and pushed a
branch to my tree "merge/upstream". The file kernel/trace/trace.c has a
conflict and kernel/trace/trace.h has a mis-merge (adds a prototype
that was already added to the header by an upstream commit).
*** NOTE ***

tracing updates for v7.1:

- Fix printf format warning for bprintf

  sunrpc uses a trace_printk() that triggers a printf warning during the
  compile. Move the __printf() attribute around for when debugging is not
  enabled the warning will go away.

- Remove redundant check for EVENT_FILE_FL_FREED in event_filter_write()

  The FREED flag is checked in the call to event_file_file() and then
  checked again right afterward, which is unneeded.

- Clean up event_file_file() and event_file_data() helpers

  These helper functions played a different role in the past, but now with
  eventfs, the READ_ONCE() isn't needed. Simplify the code a bit and also
  add a warning to event_file_data() if the file or its data is not present.

- Remove updating file->private_data in tracing open

  All access to the file private data is handled by the helper functions,
  which do not use file->private_data. Stop updating it on open.

- Show ENUM names in function arguments via BTF in function tracing

  When showing the function arguments when func-args option is set for
  function tracing, if one of the arguments is found to be an enum, show the
  name of the enum instead of its number.

- Add new trace_call__##name() API for tracepoints

  Tracepoints are enabled via static_branch() blocks, where when not
  enabled, there's only a nop that is in the code where the execution will
  just skip over it. When tracing is enabled, the nop is converted to a
  direct jump to the tracepoint code. Sometimes more calculations are
  required to be performed to update the parameters of the tracepoint. In
  this case, trace_##name##_enabled() is called which is a static_branch()
  that gets enabled only when the tracepoint is enabled. This allows the
  extra calculations to also be skipped by the nop:

  if (trace_foo_enabled()) {
      x = bar();
      trace_foo(x);
  }

  Where the x=bar() is only performed when foo is enabled. The problem with
  this approach is that there's now two static_branch() calls. One for
  checking if the tracepoint is enabled, and then again to know if the
  tracepoint should be called. The second one is redundant.

  Introduce trace_call__foo() that will call the foo() tracepoint directly
  without doing a static_branch():

  if (trace_foo_enabled()) {
      x = bar();
      trace_call__foo();
  }

- Update various locations to use the new trace_call__##name() API

- Move snapshot code out of trace.c

  Cleaning up trace.c to not be a "dump all", move the snapshot code out of
  it and into a new trace_snapshot.c file.

- Clean up some "%*.s" to "%*s"

- Allow boot kernel command line options to be called multiple times

  Have options like:

    ftrace_filter=foo ftrace_filter=bar ftrace_filter=zoo

  Equal to:

    ftrace_filter=foo,bar,zoo

- Fix ipi_raise event CPU field to be a CPU field

  The ipi_raise target_cpus field is defined as a __bitmask(). There is now a
  __cpumask() field definition. Update the field to use that.

- Have hist_field_name() use a snprintf() and not a series of strcat()

  It's safer to use snprintf() that a series of strcat().

- Fix tracepoint regfunc balancing

  A tracepoint can define a "reg" and "unreg" function that gets called
  before the tracepoint is enabled, and after it is disabled respectively.
  But on error, after the "reg" func is called and the tracepoint is not
  enabled, the "unreg" function is not called to tear down what the "reg"
  function performed.

- Fix output that shows what histograms are enabled

  Event variables are displayed incorrectly in the histogram output.

  Instead of "sched.sched_wakeup.$var", it is showing
  "$sched.sched_wakeup.var" where the '$' is in the incorrect location.

- Some other simple cleanups.


Please pull the latest trace-v7.1 tree, which can be found at:


  git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git
trace-v7.1

Tag SHA1: 391250945189f8a948e432b1ef64a3bc6c224536
Head SHA1: 621a59d8fc678762abc12ad8ad6bf616496fa4d2


Arnd Bergmann (1):
      tracing: move __printf() attribute on __ftrace_vbprintk()

CaoRuichuang (1):
      tracing: Report ipi_raise target CPUs as cpumask

David Carlier (1):
      tracepoint: balance regfunc() on func_add() failure in tracepoint_add_func()

David Laight (1):
      tracing: Remove spurious default precision from show_event_trigger/filter formats

Donglin Peng (1):
      tracing: Pretty-print enum parameters in function arguments

Pengpeng Hou (1):
      tracing: Rebuild full_name on each hist_field_name() call

Petr Pavlu (3):
      tracing: Remove unnecessary check for EVENT_FILE_FL_FREED
      tracing: Clean up access to trace_event_file from a file pointer
      tracing: Free up file->private_data for use by individual events

Randy Dunlap (1):
      tracing: trace_mmap.h: fix a kernel-doc warning

Steven Rostedt (3):
      tracing: Move snapshot code out of trace.c and into trace_snapshot.c
      tracing: Remove tracing_alloc_snapshot() when snapshot isn't defined
      tracing: Remove duplicate latency_fsnotify() stub

Tom Zanussi (2):
      tracing: Fix fully-qualified variable reference printing in histograms
      selftests/ftrace: Add test case for fully-qualified variable references

Vineeth Pillai (Google) (7):
      tracepoint: Add trace_call__##name() API
      kernel: Use trace_call__##name() at guarded tracepoint call sites
      i2c: Use trace_call__##name() at guarded tracepoint call sites
      spi: Use trace_call__##name() at guarded tracepoint call sites
      btrfs: Use trace_call__##name() at guarded tracepoint call sites
      mm: damon: Use trace_call__##name() at guarded tracepoint call sites
      cpufreq: Use trace_call__##name() at guarded tracepoint call sites

Wesley Atwell (2):
      tracing: Append repeated boot-time tracing parameters
      tracing: Preserve repeated trace_trigger boot parameters

----
 drivers/cpufreq/amd-pstate.c                       |   10 +-
 drivers/cpufreq/cpufreq.c                          |    2 +-
 drivers/cpufreq/intel_pstate.c                     |    2 +-
 drivers/i2c/i2c-core-slave.c                       |    2 +-
 drivers/spi/spi-axi-spi-engine.c                   |    4 +-
 fs/btrfs/extent_map.c                              |    4 +-
 fs/btrfs/raid56.c                                  |    4 +-
 include/linux/ftrace.h                             |    2 +-
 include/linux/trace_printk.h                       |    1 -
 include/linux/tracepoint.h                         |   11 +
 include/trace/events/ipi.h                         |    6 +-
 include/uapi/linux/trace_mmap.h                    |    1 +
 kernel/irq_work.c                                  |    2 +-
 kernel/sched/ext.c                                 |    2 +-
 kernel/smp.c                                       |    2 +-
 kernel/trace/Makefile                              |    1 +
 kernel/trace/ftrace.c                              |   12 +-
 kernel/trace/trace.c                               | 1312 ++------------------
 kernel/trace/trace.h                               |  126 +-
 kernel/trace/trace_events.c                        |   31 +-
 kernel/trace/trace_events_hist.c                   |   29 +-
 kernel/trace/trace_kprobe.c                        |    3 +-
 kernel/trace/trace_output.c                        |   12 +-
 kernel/trace/trace_printk.c                        |    1 +
 kernel/trace/trace_snapshot.c                      | 1066 ++++++++++++++++
 kernel/tracepoint.c                                |    2 +
 mm/damon/core.c                                    |    2 +-
 .../inter-event/trigger-fully-qualified-var-ref.tc |   34 +
 28 files changed, 1396 insertions(+), 1290 deletions(-)
 create mode 100644 kernel/trace/trace_snapshot.c
 create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-fully-qualified-var-ref.tc
---------------------------