On Fri, Feb 15, 2019 at 01:53:51PM -0800, Song Liu wrote: > This patch enables perf-record to save btf information as headers to > perf.data A new header type HEADER_BTF is introduced for this data. > > Signed-off-by: Song Liu <songliubrav...@fb.com> > --- > tools/perf/util/header.c | 99 +++++++++++++++++++++++++++++++++++++++- > tools/perf/util/header.h | 1 + > 2 files changed, 99 insertions(+), 1 deletion(-) > > diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c > index 0889ad797940..2de4f4e9b590 100644 > --- a/tools/perf/util/header.c > +++ b/tools/perf/util/header.c > @@ -1127,6 +1127,45 @@ static int write_bpf_prog_info(struct feat_fd *ff, > return ret; > } > > +static int write_btf(struct feat_fd *ff, > + struct perf_evlist *evlist __maybe_unused) > +{ > + struct perf_env *env = &ff->ph->env; > + struct rb_root *root; > + struct rb_node *next; > + u32 count = 0; > + int ret; > + > + down_read(&env->bpf_progs.bpf_info_lock); > + > + root = &env->bpf_progs.btfs; > + next = rb_first(root); > + while (next) { > + ++count; > + next = rb_next(next); > + } > + > + ret = do_write(ff, &count, sizeof(count)); > + > + if (ret < 0) > + goto out; > + > + next = rb_first(root); > + while (next) { > + struct btf_node *node; > + > + node = rb_entry(next, struct btf_node, rb_node); > + next = rb_next(&node->rb_node); > + ret = do_write(ff, node, > + sizeof(struct btf_node) + node->data_size);
hm, you write the whole struct btf_node with struct rb_node? why? thanks, jirka