[v4,0/9] tracing: Improbe BTF support on probe events

Message

Masami Hiramatsu (Google) July 31, 2023, 7:30 a.m. UTC

Hi,

Here is the 4th version of series to improve the BTF support on probe events.
The previous series is here:

https://lore.kernel.org/all/169037639315.607919.2613476171148037242.stgit@devnote2/

This version updates the btf_find_struct_member() to use a simple stack
to walk through the anonymous unions/structures instead of recursive call.
Also, returning int error code from query_btf_context()
if !CONFIG_PROBE_EVENTS_BTF_ARGS.

This series enables {f,k}probe events to access the members of data
structures using BTF from arguments and return value. This also adds
some new APIs to BTF so that other users can use BTF to find function
prototypes and the members of data structures.

This series can be applied on top of "probes/core" branch of
https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git/

You can also get this series from:

git://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux.git topic/fprobe-event-ext

Thank you,

---

Masami Hiramatsu (Google) (9):
      tracing/probes: Support BTF argument on module functions
      bpf/btf: tracing: Move finding func-proto API and getting func-param API to BTF
      bpf/btf: Add a function to search a member of a struct/union
      tracing/probes: Support BTF based data structure field access
      tracing/probes: Support BTF field access from $retval
      tracing/probes: Add string type check with BTF
      tracing/fprobe-event: Assume fprobe is a return event by $retval
      selftests/ftrace: Add BTF fields access testcases
      Documentation: tracing: Update fprobe event example with BTF field


 Documentation/trace/fprobetrace.rst                |   64 ++-
 include/linux/btf.h                                |    8 
 kernel/bpf/btf.c                                   |   89 ++++
 kernel/trace/trace_eprobe.c                        |    4 
 kernel/trace/trace_fprobe.c                        |   59 ++
 kernel/trace/trace_kprobe.c                        |    1 
 kernel/trace/trace_probe.c                         |  494 +++++++++++++++-----
 kernel/trace/trace_probe.h                         |   27 +
 kernel/trace/trace_uprobe.c                        |    1 
 .../ftrace/test.d/dynevent/add_remove_btfarg.tc    |   14 +
 .../ftrace/test.d/dynevent/fprobe_syntax_errors.tc |    6 
 11 files changed, 593 insertions(+), 174 deletions(-)

--
Masami Hiramatsu (Google) <[e-mail]>