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) <mhiramat@xxxxxxxxxx>
