From: Alexei Starovoitov <ast@xxxxxxxxxx>
Generealize light skeleton by hiding mmap details in skel_internal.h
In this form generated lskel.h is usable both by user space and by the kernel.
Note that previously #include <bpf/bpf.h> was in *.lskel.h file.
To avoid #ifdef-s in a generated lskel.h the include of bpf.h is moved
to skel_internal.h, but skel_internal.h is also used by gen_loader.c
which is part of libbpf. Therefore skel_internal.h does #include "bpf.h"
in case of user space, so gen_loader.c and lskel.h have necessary definitions.
Acked-by: Yonghong Song <yhs@xxxxxx>
Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
tools/bpf/bpftool/gen.c | 55 +++++++++++++++++++++++++++--------------
1 file changed, 37 insertions(+), 18 deletions(-)
diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c
index eacfc6a2060d..9e0b45bdc5cb 100644
--- a/tools/bpf/bpftool/gen.c
+++ b/tools/bpf/bpftool/gen.c
@@ -472,7 +472,7 @@ static void codegen_destroy(struct bpf_object *obj, const char *obj_name)
continue;
if (bpf_map__is_internal(map) &&
(bpf_map__map_flags(map) & BPF_F_MMAPABLE))
- printf("\tmunmap(skel->%1$s, %2$zd);\n",
+ printf("\tskel_free_map_data(skel->%1$s, skel->maps.%1$s.initial_value, %2$zd);\n",
ident, bpf_map_mmap_sz(map));
codegen("\
\n\
@@ -481,7 +481,7 @@ static void codegen_destroy(struct bpf_object *obj, const char *obj_name)
}
codegen("\
\n\
- free(skel); \n\
+ skel_free(skel); \n\
} \n\
",
obj_name);
@@ -525,7 +525,7 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h
{ \n\
struct %1$s *skel; \n\
\n\
- skel = calloc(sizeof(*skel), 1); \n\
+ skel = skel_alloc(sizeof(*skel)); \n\
if (!skel) \n\
goto cleanup; \n\
skel->ctx.sz = (void *)&skel->links - (void *)skel; \n\
@@ -544,18 +544,14 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h
codegen("\
\n\
- skel->%1$s = \n\
- mmap(NULL, %2$zd, PROT_READ | PROT_WRITE,\n\
- MAP_SHARED | MAP_ANONYMOUS, -1, 0); \n\
- if (skel->%1$s == (void *) -1) \n\
- goto cleanup; \n\
- memcpy(skel->%1$s, (void *)\"\\ \n\
- ", ident, bpf_map_mmap_sz(map));
+ skel->%1$s = skel_prep_map_data((void *)\"\\ \n\
+ ", ident);
mmap_data = bpf_map__initial_value(map, &mmap_size);
print_hex(mmap_data, mmap_size);
- printf("\", %2$zd);\n"
- "\tskel->maps.%1$s.initial_value = (__u64)(long)skel->%1$s;\n",
- ident, mmap_size);
+ printf("\", %1$zd, %2$zd);\n"
+ " if (!skel->%3$s)\n"
+ " goto cleanup;\n",
+ bpf_map_mmap_sz(map), mmap_size, ident);
}
codegen("\
\n\
@@ -592,6 +588,24 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h
codegen("\
\n\
\"; \n\
+ ");
+ bpf_object__for_each_map(map, obj) {
+ size_t mmap_size = 0;
+
+ if (!get_map_ident(map, ident, sizeof(ident)))
+ continue;
+
+ if (!bpf_map__is_internal(map) ||
+ !(bpf_map__map_flags(map) & BPF_F_MMAPABLE))
+ continue;
+
+ bpf_map__initial_value(map, &mmap_size);
+ printf("\tskel->maps.%1$s.initial_value ="
+ " skel_prep_init_value((void **)&skel->%1$s, %2$zd, %3$zd);\n",
+ ident, bpf_map_mmap_sz(map), mmap_size);
+ }
+ codegen("\
+ \n\
err = bpf_load_and_run(&opts); \n\
if (err < 0) \n\
return err; \n\
@@ -611,14 +625,21 @@ static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *h
else
mmap_flags = "PROT_READ | PROT_WRITE";
- printf("\tskel->%1$s =\n"
- "\t\tmmap(skel->%1$s, %2$zd, %3$s, MAP_SHARED | MAP_FIXED,\n"
- "\t\t\tskel->maps.%1$s.map_fd, 0);\n",
+ codegen("\
+ \n\
+ skel->%1$s = skel_finalize_map_data(&skel->maps.%1$s.initial_value, \n\
+ %2$zd, %3$s, skel->maps.%1$s.map_fd);\n\
+ if (!skel->%1$s) \n\
+ goto cleanup; \n\
+ ",
ident, bpf_map_mmap_sz(map), mmap_flags);
}
codegen("\
\n\
return 0; \n\
+ cleanup: __attribute__((__unused__)); \n\
+ %1$s__destroy(skel); \n\
+ return -ENOMEM; \n\
} \n\
\n\
static inline struct %1$s * \n\
@@ -751,8 +772,6 @@ static int do_skeleton(int argc, char **argv)
#ifndef %2$s \n\
#define %2$s \n\
\n\
- #include <stdlib.h> \n\
- #include <bpf/bpf.h> \n\
#include <bpf/skel_internal.h> \n\
\n\
struct %1$s { \n\
--
2.30.2
