[v2,00/10] Refactor APIs for creating output handler

Message

Tzvetomir Stoyanov (VMware) Nov. 11, 2021, 3:03 p.m. UTC

In the trace-cmd library there are various APIs for allocating and
initializing output handler to a trace file. The existing APIs are use
case oriented, with a lot of parameters. Extending them for new use
cases, adding more input parameters, will make the library more complex
and not easy to use.
Almost all use case oriented APIs for output handler creation are
removed and replaced with new flow, which is easier to be extended with
new parameters.

Removed APIs:
 tracecmd_create_init_fd_msg()
 tracecmd_create_init_file_glob()
 tracecmd_create_init_fd_glob()
 tracecmd_create_init_file_override()

New APIs:
 tracecmd_output_allocate()
 tracecmd_output_set_msg()
 tracecmd_output_set_trace_dir()
 tracecmd_output_set_kallsyms()
 tracecmd_output_set_from_input()
 tracecmd_output_write_init()
 tracecmd_output_write_headers()

The new tracecmd_output_allocate() API allocates memory and performs
minimal initialization of an output handler to a trace file. No data
is written in the file.
The tracecmd_output_set_...() APIs can be used to set various
parameters to the newly allocated output handler, that affect the way
the data is written into the file.
When the output handler is configured for the desired use case, the
tracecmd_output_write_init() is used to start writing to the file, it
writes initial magic bytes.
The tracecmd_output_write_headers() API is used to write the initial
headers into the file.

This patch-set depends on:
  "trace-cmd fixes and clean-ups" patch set.

v2 changes:
 - Rebased on top of the latest master.

Tzvetomir Stoyanov (VMware) (10):
  trace-cmd library: New API for allocating an output handler
  trace-cmd library: New API for setting a message context to an output
    handler
  trace-cmd library: New API for setting a custom trace directory to an
    output handler
  trace-cmd library: New API for setting a custom kallsyms to an output
    handler
  trace-cmd library: New API to inherit parameters from an existing
    trace file
  trace-cmd library: New API tracecmd_output_write_init
  trace-cmd library: New API to write headers of a trace file
  trace-cmd library: Use the new flow when creating output handler
  trace-cmd: Use the new flow when creating output handler
  trace-cmd library: Remove deprecated APIs for creating an output
    handler

 .../include/private/trace-cmd-private.h       |  25 +-
 lib/trace-cmd/trace-output.c                  | 397 +++++++++++-------
 tracecmd/trace-record.c                       |  55 ++-
 tracecmd/trace-restore.c                      |  32 +-
 4 files changed, 347 insertions(+), 162 deletions(-)

Comments

Steven Rostedt Nov. 24, 2021, 3:33 a.m. UTC | #1

On Thu, 11 Nov 2021 17:03:11 +0200
"Tzvetomir Stoyanov (VMware)" <[e-mail]> wrote:

> This patch-set depends on:
>   "trace-cmd fixes and clean-ups" patch set.

FYI, please have a link to the patches that are dependent. Ideally a
mailing list archive link, or at a minimum, a link to patchwork.

But just a subject line is not easy to find, especially if it's been
archived.

-- Steve