Oops, ignore this. I forgot to update subjects. On Thu, 23 Sep 2021 21:38:55 +0900 Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote: > Hi Steve, > > Here I share my testing patch of the BTF for kprobe events. > Currently this only allow user to specify '$$args' for > tracing all arguments of the function. This is only > avaialbe if > - the probe point is on the function entry > - the kernel is compiled with BTF (CONFIG_DEBUG_INFO_BTF) > - the kernel is enables BPF (CONFIG_BPF_SYSCALL) > > And Special thanks to Sven! Most of BTF handling part of > this patch comes from his patch [1] > > [1] https://stackframe.org/0001-ftrace-arg-hack.patch > > What I thought while coding this were; > - kernel/bpf/btf.c can be moved under lib/ so that > the other subsystems can reuse it, independent > from BPF. (Also, this should depends on CONFIG_DEBUG_INFO_BTF) > - some more utility functions can be exposed. > e.g. I copied btf_type_int() from btf.c > - If there are more comments for the BTF APIs, it will > be more useful... > - Overall, the BTF is easy to understand for who > already understand DWARF. Great work! > - I think I need 'ptr' and 'bool' types for fetcharg types. > > Anyway, this is just for testing. I have to add some > more cleanup, features and documentations, etc. > > Thank you, > > --- > > Masami Hiramatsu (1): > tracing/kprobe: Support $$args for function entry > > > kernel/trace/trace_kprobe.c | 60 ++++++++++++++++++++++++- > kernel/trace/trace_probe.c | 105 +++++++++++++++++++++++++++++++++++++++++++ > kernel/trace/trace_probe.h | 5 ++ > 3 files changed, 168 insertions(+), 2 deletions(-) > > -- > Masami Hiramatsu (Linaro) <mhiramat@xxxxxxxxxx> -- Masami Hiramatsu <mhiramat@xxxxxxxxxx>
