perf/core improvements and fixes:

perf record:

  Alexey Budankov:

  - Implement --mmap-flush=<number> option, to control a threshold for draining
    the mmap ring buffers and consequently the size of the write calls to the
    output, be it, pipe mode or soon a compressor that with bigger
    buffers will do a better job before dumping compressed data into a new content mode, which is in the final steps of reviewing and testing.

perf trace:

  Arnaldo Carvalho de Melo:

  - Add 'string' event alias to select syscalls with string args, i.e. for testing
    the BPF program used to copy those strings, allow for:

    # perf trace -e string

    To select all the syscalls that have things like pathnames.

  - Use a PERCPU_ARRAY BPF map to copy more string bytes than what is possible using
    the BPF stack, just like pioneered by the sysdig tool.

Feature detection:

  Alexey Budankov:

  - Implement libzstd feature check, which is a library that provides a uniform
    API to various compression formats, will be used in 'perf record', see note
    about --mmap-flush feature.

perf stat:

  Andi Kleen:

  - Implement a tool specific 'duration_time' event to allow showing the "time
    elapsed" line in the default 'perf stat' output as one of the events that
    can be asked for when using --field-separator and other script consumable

Intel vendor events (JSON files):

  Andi Kleen:

  - Update metrics from TMAM 3.5.

  - Update events:

    Bonnell to V4
    Broadwell-DE to v7
    Broadwell to v23
    BroadwellX to v14
    GoldmontPlus to v1.01
    Goldmont to v13
    Haswell to v28
    HaswellX to v20
    IvyBridge to v21
    IvyTown to v20
    JakeTown to v20
    KnightsLanding to v9
    SandyBridge to v16
    Silvermont to v14
    Skylake to v42
    SkylakeX to v1.12

IBM S/390 vendor events (JSON):

  Thomas Richter:

  - Fix s390 counter long description for L1D_RO_EXCL_WRITES.

tools lib traceevent:

  Steven Rostedt (Red Hat):

  - Add more debugging to see various internal ring buffer entries.

  Steven Rostedt (VMWare):

  - Handle trace_printk() "%px".
  - Add mono clocks to be parsed in seconds.
  - Removed unneeded !! and return parenthesis.

  Tzvetomir Stoyanov :

  - Implement a new API, tep_list_events_copy().
  - Implement new traceevent APIs for accessing struct tep_handler fields.
  - Remove tep filter trivial APIs, not used anymore.
  - Remove call to exit() from tep_filter_add_filter_str(), library routines shouldn't
    kill tools using it.
  - Make traceevent APIs more consistent.

Signed-off-by: Arnaldo Carvalho de Melo <>

perf vendor events intel: Update Silvermont to v14

Signed-off-by: Andi Kleen <>
Cc: Kan Liang <>
Cc: Jiri Olsa <>
Signed-off-by: Arnaldo Carvalho de Melo <>
3 files changed