Generate preload(), to pin defined objects. For pinning, use the bpf_obj_do_pin_kernel() function, just exported.
Signed-off-by: Roberto Sassu roberto.sassu@huawei.com --- kernel/bpf/preload/bpf_preload_kern.c | 24 ------- .../bpf/preload/iterators/iterators.lskel.h | 26 ++++++++ tools/bpf/bpftool/gen.c | 64 +++++++++++++++++++ 3 files changed, 90 insertions(+), 24 deletions(-)
diff --git a/kernel/bpf/preload/bpf_preload_kern.c b/kernel/bpf/preload/bpf_preload_kern.c index 8b49beb2b2d6..0869c889255c 100644 --- a/kernel/bpf/preload/bpf_preload_kern.c +++ b/kernel/bpf/preload/bpf_preload_kern.c @@ -5,30 +5,6 @@ #include <linux/bpf_preload.h> #include "iterators/iterators.lskel.h"
-static int preload(struct dentry *parent) -{ - int err; - - bpf_link_inc(dump_bpf_map_link); - bpf_link_inc(dump_bpf_prog_link); - - err = bpf_obj_do_pin_kernel(parent, "maps.debug", dump_bpf_map_link, - BPF_TYPE_LINK); - if (err) - goto undo; - - err = bpf_obj_do_pin_kernel(parent, "progs.debug", dump_bpf_prog_link, - BPF_TYPE_LINK); - if (err) - goto undo; - - return 0; -undo: - bpf_link_put(dump_bpf_map_link); - bpf_link_put(dump_bpf_prog_link); - return err; -} - static struct bpf_preload_ops ops = { .preload = preload, .owner = THIS_MODULE, diff --git a/kernel/bpf/preload/iterators/iterators.lskel.h b/kernel/bpf/preload/iterators/iterators.lskel.h index 4afd983ad40e..75b2e94b7547 100644 --- a/kernel/bpf/preload/iterators/iterators.lskel.h +++ b/kernel/bpf/preload/iterators/iterators.lskel.h @@ -448,4 +448,30 @@ static void free_objs_and_skel(void) iterators_bpf__destroy(skel); }
+static int preload(struct dentry *parent) +{ + int err; + + bpf_link_inc(dump_bpf_map_link); + bpf_link_inc(dump_bpf_prog_link); + + err = bpf_obj_do_pin_kernel(parent, "maps.debug", + dump_bpf_map_link, + BPF_TYPE_LINK); + if (err) + goto undo; + + err = bpf_obj_do_pin_kernel(parent, "progs.debug", + dump_bpf_prog_link, + BPF_TYPE_LINK); + if (err) + goto undo; + + return 0; +undo: + bpf_link_put(dump_bpf_map_link); + bpf_link_put(dump_bpf_prog_link); + return err; +} + #endif /* __ITERATORS_BPF_SKEL_H__ */ diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index e167aa092b7f..fa2c6022b80d 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -701,6 +701,69 @@ static void codegen_preload_free(struct bpf_object *obj, const char *obj_name) ", obj_name); }
+static void codegen_preload(struct bpf_object *obj, const char *obj_name) +{ + struct bpf_program *prog; + const char *link_name; + + codegen("\ + \n\ + \n\ + static int preload(struct dentry *parent) \n\ + { \n\ + int err; \n\ + \n\ + "); + + bpf_object__for_each_program(prog, obj) { + codegen("\ + \n\ + bpf_link_inc(%s_link); \n\ + ", bpf_program__name(prog)); + } + + bpf_object__for_each_program(prog, obj) { + link_name = bpf_program__name(prog); + /* These need to be hardcoded for compatibility reasons. */ + if (!strcmp(obj_name, "iterators_bpf")) { + if (!strcmp(link_name, "dump_bpf_map")) + link_name = "maps.debug"; + else if (!strcmp(link_name, "dump_bpf_prog")) + link_name = "progs.debug"; + } + + codegen("\ + \n\ + \n\ + err = bpf_obj_do_pin_kernel(parent, "%s", \n\ + %s_link, \n\ + BPF_TYPE_LINK); \n\ + if (err) \n\ + goto undo; \n\ + ", link_name, bpf_program__name(prog)); + } + + codegen("\ + \n\ + \n\ + return 0; \n\ + undo: \n\ + "); + + bpf_object__for_each_program(prog, obj) { + codegen("\ + \n\ + bpf_link_put(%s_link); \n\ + ", bpf_program__name(prog)); + } + + codegen("\ + \n\ + return err; \n\ + } \n\ + "); +} + static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *header_guard) { DECLARE_LIBBPF_OPTS(gen_loader_opts, opts); @@ -852,6 +915,7 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h if (gen_preload_methods) { codegen_preload_vars(obj, obj_name); codegen_preload_free(obj, obj_name); + codegen_preload(obj, obj_name); }
codegen("\