lkml.org 
[lkml]   [2022]   [Mar]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    Date
    SubjectRe: [PATCH 06/10] libbpf: Add libbpf_kallsyms_parse function
    On Tue, Feb 22, 2022 at 9:07 AM Jiri Olsa <jolsa@kernel.org> wrote:
    >
    > Move the kallsyms parsing in internal libbpf_kallsyms_parse
    > function, so it can be used from other places.
    >
    > It will be used in following changes.
    >
    > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
    > ---

    LGTM

    Acked-by: Andrii Nakryiko <andrii@kernel.org>


    > tools/lib/bpf/libbpf.c | 62 ++++++++++++++++++++-------------
    > tools/lib/bpf/libbpf_internal.h | 5 +++
    > 2 files changed, 43 insertions(+), 24 deletions(-)
    >
    > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
    > index ad43b6ce825e..fb530b004a0d 100644
    > --- a/tools/lib/bpf/libbpf.c
    > +++ b/tools/lib/bpf/libbpf.c
    > @@ -7172,12 +7172,10 @@ static int bpf_object__sanitize_maps(struct bpf_object *obj)
    > return 0;
    > }
    >
    > -static int bpf_object__read_kallsyms_file(struct bpf_object *obj)
    > +int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *ctx)
    > {
    > char sym_type, sym_name[500];
    > unsigned long long sym_addr;
    > - const struct btf_type *t;
    > - struct extern_desc *ext;
    > int ret, err = 0;
    > FILE *f;
    >
    > @@ -7196,35 +7194,51 @@ static int bpf_object__read_kallsyms_file(struct bpf_object *obj)
    > if (ret != 3) {
    > pr_warn("failed to read kallsyms entry: %d\n", ret);
    > err = -EINVAL;
    > - goto out;
    > + break;
    > }
    >
    > - ext = find_extern_by_name(obj, sym_name);
    > - if (!ext || ext->type != EXT_KSYM)
    > - continue;
    > -
    > - t = btf__type_by_id(obj->btf, ext->btf_id);
    > - if (!btf_is_var(t))
    > - continue;
    > -
    > - if (ext->is_set && ext->ksym.addr != sym_addr) {
    > - pr_warn("extern (ksym) '%s' resolution is ambiguous: 0x%llx or 0x%llx\n",
    > - sym_name, ext->ksym.addr, sym_addr);
    > - err = -EINVAL;
    > - goto out;
    > - }
    > - if (!ext->is_set) {
    > - ext->is_set = true;
    > - ext->ksym.addr = sym_addr;
    > - pr_debug("extern (ksym) %s=0x%llx\n", sym_name, sym_addr);
    > - }
    > + err = cb(sym_addr, sym_type, sym_name, ctx);
    > + if (err)
    > + break;
    > }
    >
    > -out:
    > fclose(f);
    > return err;
    > }
    >
    > +static int kallsyms_cb(unsigned long long sym_addr, char sym_type,
    > + const char *sym_name, void *ctx)
    > +{
    > + struct bpf_object *obj = ctx;
    > + const struct btf_type *t;
    > + struct extern_desc *ext;
    > +
    > + ext = find_extern_by_name(obj, sym_name);
    > + if (!ext || ext->type != EXT_KSYM)
    > + return 0;
    > +
    > + t = btf__type_by_id(obj->btf, ext->btf_id);
    > + if (!btf_is_var(t))
    > + return 0;
    > +
    > + if (ext->is_set && ext->ksym.addr != sym_addr) {
    > + pr_warn("extern (ksym) '%s' resolution is ambiguous: 0x%llx or 0x%llx\n",
    > + sym_name, ext->ksym.addr, sym_addr);
    > + return -EINVAL;
    > + }
    > + if (!ext->is_set) {
    > + ext->is_set = true;
    > + ext->ksym.addr = sym_addr;
    > + pr_debug("extern (ksym) %s=0x%llx\n", sym_name, sym_addr);
    > + }
    > + return 0;
    > +}
    > +
    > +static int bpf_object__read_kallsyms_file(struct bpf_object *obj)
    > +{
    > + return libbpf_kallsyms_parse(kallsyms_cb, obj);
    > +}
    > +
    > static int find_ksym_btf_id(struct bpf_object *obj, const char *ksym_name,
    > __u16 kind, struct btf **res_btf,
    > struct module_btf **res_mod_btf)
    > diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h
    > index 4fda8bdf0a0d..b6247dc7f8eb 100644
    > --- a/tools/lib/bpf/libbpf_internal.h
    > +++ b/tools/lib/bpf/libbpf_internal.h
    > @@ -449,6 +449,11 @@ __s32 btf__find_by_name_kind_own(const struct btf *btf, const char *type_name,
    >
    > extern enum libbpf_strict_mode libbpf_mode;
    >
    > +typedef int (*kallsyms_cb_t)(unsigned long long sym_addr, char sym_type,
    > + const char *sym_name, void *ctx);
    > +
    > +int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *arg);
    > +
    > /* handle direct returned errors */
    > static inline int libbpf_err(int ret)
    > {
    > --
    > 2.35.1
    >

    \
     
     \ /
      Last update: 2022-03-05 00:13    [W:4.847 / U:0.180 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site