mbox series

[for-linus,0/6] tracing: Fixes for 6.3

Message ID 20230403212125.244064799@goodmis.org
Headers
Series tracing: Fixes for 6.3 |

Message

Steven Rostedt April 3, 2023, 9:21 p.m. UTC 
  Tracing fixes for 6.3:

- Fix timerlat notification, as it was not triggering the
  notify to users when a new max latency was hit.

- Do not trigger max latency if the tracing is off.
  When tracing is off, the ring buffer is not updated, it
  does not make sense to notify when there's a new max latency
  detected by the tracer, as why that latency happened is not available.
  The tracing logic still runs when the ring buffer is disabled, but
  it should not be triggering notifications.

- Fix race on freeing the synthetic event "last_cmd" variable by
  adding a mutex around it.

- Fix race between reader and writer of the ring buffer by adding
  memory barriers. When the writer is still on the reader page
  it must have its content visible on the buffer before it moves
  the commit index that the reader uses to know how much content is
  on the page.

- Make get_lock_parent_ip() always inlined, as it uses _THIS_IP_
  and _RET_IP_, which gets broken if it is not inlined.

- Make __field(int, arr[5]) in a TRACE_EVENT() macro fail to build.
  The field formats of trace events are calculated by using sizeof(type)
  and other means by what is passed into the structure macros like
  __field(). The __field() macro is only meant for atom types like
  int, long, short, pointer, etc. It is not meant for arrays. But
  the code will currently compile with arrays, but then the format
  produced will be inaccurate, and user space parsing tools will break.
  Two bugs have already been fixed, now add code that will make the
  kernel fail to build if another trace event includes this buggy
  field format.


  git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git
trace/urgent

Head SHA1: f82e7ca019dfad3b006fd3b772f7ac569672db55


Daniel Bristot de Oliveira (2):
      tracing/timerlat: Notify new max thread latency
      tracing/osnoise: Fix notify new tracing_max_latency

John Keeping (1):
      ftrace: Mark get_lock_parent_ip() __always_inline

Steven Rostedt (Google) (1):
      tracing: Error if a trace event has an array for a __field()

Tze-nan Wu (1):
      tracing/synthetic: Fix races on freeing last_cmd

Zheng Yejian (1):
      ring-buffer: Fix race while reader and writer are on the same page

----
 include/linux/ftrace.h                    |  2 +-
 include/trace/stages/stage5_get_offsets.h | 21 +++++++++++++++++----
 kernel/trace/ring_buffer.c                | 13 ++++++++++++-
 kernel/trace/trace_events_synth.c         | 19 +++++++++++++++----
 kernel/trace/trace_osnoise.c              |  4 +++-
 5 files changed, 48 insertions(+), 11 deletions(-)