Skip to content

Commit

Permalink
bpftool: use bpf_program__get_prog_info_linear() in prog.c:do_dump()
Browse files Browse the repository at this point in the history 
This patches uses bpf_program__get_prog_info_linear() to simplify the
logic in prog.c do_dump().

Committer testing:

Before:

  # bpftool prog dump xlated id 208 > /tmp/dump.xlated.before
  # bpftool prog dump jited id 208 > /tmp/dump.jited.before
  # bpftool map dump id 107 > /tmp/map.dump.before

After:

  # ~acme/git/perf/tools/bpf/bpftool/bpftool map dump id 107 > /tmp/map.dump.after
  # ~acme/git/perf/tools/bpf/bpftool/bpftool prog dump xlated id 208 > /tmp/dump.xlated.after
  # ~acme/git/perf/tools/bpf/bpftool/bpftool prog dump jited id 208 > /tmp/dump.jited.after
  # diff -u /tmp/dump.xlated.before /tmp/dump.xlated.after
  # diff -u /tmp/dump.jited.before /tmp/dump.jited.after
  # diff -u /tmp/map.dump.before /tmp/map.dump.after
  # ~acme/git/perf/tools/bpf/bpftool/bpftool prog dump xlated id 208
     0: (bf) r6 = r1
     1: (85) call bpf_get_current_pid_tgid#80800
     2: (63) *(u32 *)(r10 -328) = r0
     3: (bf) r2 = r10
     4: (07) r2 += -328
     5: (18) r1 = map[id:107]
     7: (85) call __htab_map_lookup_elem#85680
     8: (15) if r0 == 0x0 goto pc+1
     9: (07) r0 += 56
    10: (b7) r7 = 0
    11: (55) if r0 != 0x0 goto pc+52
    12: (bf) r1 = r10
    13: (07) r1 += -328
    14: (b7) r2 = 64
    15: (bf) r3 = r6
    16: (85) call bpf_probe_read#-46848
    17: (bf) r2 = r10
    18: (07) r2 += -320
    19: (18) r1 = map[id:106]
    21: (07) r1 += 208
    22: (61) r0 = *(u32 *)(r2 +0)
    23: (35) if r0 >= 0x200 goto pc+3
    24: (67) r0 <<= 3
    25: (0f) r0 += r1
    26: (05) goto pc+1
    27: (b7) r0 = 0
    28: (15) if r0 == 0x0 goto pc+35
    29: (71) r1 = *(u8 *)(r0 +0)
    30: (15) if r1 == 0x0 goto pc+33
    31: (b7) r5 = 64
    32: (79) r1 = *(u64 *)(r10 -320)
    33: (15) if r1 == 0x2 goto pc+2
    34: (15) if r1 == 0x101 goto pc+3
    35: (55) if r1 != 0x15 goto pc+19
    36: (79) r3 = *(u64 *)(r6 +16)
    37: (05) goto pc+1
    38: (79) r3 = *(u64 *)(r6 +24)
    39: (15) if r3 == 0x0 goto pc+15
    40: (b7) r1 = 0
    41: (63) *(u32 *)(r10 -260) = r1
    42: (bf) r1 = r10
    43: (07) r1 += -256
    44: (b7) r2 = 256
    45: (85) call bpf_probe_read_str#-46704
    46: (b7) r5 = 328
    47: (63) *(u32 *)(r10 -264) = r0
    48: (bf) r1 = r0
    49: (67) r1 <<= 32
    50: (77) r1 >>= 32
    51: (25) if r1 > 0xff goto pc+3
    52: (07) r0 += 72
    53: (57) r0 &= 255
    54: (bf) r5 = r0
    55: (bf) r4 = r10
    56: (07) r4 += -328
    57: (bf) r1 = r6
    58: (18) r2 = map[id:105]
    60: (18) r3 = 0xffffffff
    62: (85) call bpf_perf_event_output_tp#-45104
    63: (bf) r7 = r0
    64: (bf) r0 = r7
    65: (95) exit
  #

Signed-off-by: Song Liu <[email protected]>
Reviewed-by: Jiri Olsa <[email protected]>
Acked-by: Daniel Borkmann <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stanislav Fomichev <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
  • Loading branch information
@liu-song-6 @acmel
liu-song-6 authored and acmel committed Mar 19, 2019
1 parent 34be164 commit cae73f2
Showing 1 changed file with 59 additions and 207 deletions.
266 changes: 59 additions & 207 deletions tools/bpf/bpftool/prog.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -401,41 +401,31 @@ static int do_show(int argc, char **argv)

static int do_dump(int argc, char **argv)
{
unsigned int finfo_rec_size, linfo_rec_size, jited_linfo_rec_size;
void *func_info = NULL, *linfo = NULL, *jited_linfo = NULL;
unsigned int nr_finfo, nr_linfo = 0, nr_jited_linfo = 0;
struct bpf_prog_info_linear *info_linear;
struct bpf_prog_linfo *prog_linfo = NULL;
unsigned long *func_ksyms = NULL;
struct bpf_prog_info info = {};
unsigned int *func_lens = NULL;
enum {DUMP_JITED, DUMP_XLATED} mode;
const char *disasm_opt = NULL;
unsigned int nr_func_ksyms;
unsigned int nr_func_lens;
struct bpf_prog_info *info;
struct dump_data dd = {};
__u32 len = sizeof(info);
void *func_info = NULL;
struct btf *btf = NULL;
unsigned int buf_size;
char *filepath = NULL;
bool opcodes = false;
bool visual = false;
char func_sig[1024];
unsigned char *buf;
bool linum = false;
__u32 *member_len;
__u64 *member_ptr;
__u32 member_len;
__u64 arrays;
ssize_t n;
int err;
int fd;

if (is_prefix(*argv, "jited")) {
if (disasm_init())
return -1;

member_len = &info.jited_prog_len;
member_ptr = &info.jited_prog_insns;
mode = DUMP_JITED;
} else if (is_prefix(*argv, "xlated")) {
member_len = &info.xlated_prog_len;
member_ptr = &info.xlated_prog_insns;
mode = DUMP_XLATED;
} else {
p_err("expected 'xlated' or 'jited', got: %s", *argv);
return -1;
Expand Down Expand Up @@ -474,175 +464,50 @@ static int do_dump(int argc, char **argv)
return -1;
}

err = bpf_obj_get_info_by_fd(fd, &info, &len);
if (err) {
p_err("can't get prog info: %s", strerror(errno));
return -1;
}

if (!*member_len) {
p_info("no instructions returned");
close(fd);
return 0;
}
if (mode == DUMP_JITED)
arrays = 1UL << BPF_PROG_INFO_JITED_INSNS;
else
arrays = 1UL << BPF_PROG_INFO_XLATED_INSNS;

buf_size = *member_len;
arrays |= 1UL << BPF_PROG_INFO_JITED_KSYMS;
arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;

buf = malloc(buf_size);
if (!buf) {
p_err("mem alloc failed");
close(fd);
info_linear = bpf_program__get_prog_info_linear(fd, arrays);
close(fd);
if (IS_ERR_OR_NULL(info_linear)) {
p_err("can't get prog info: %s", strerror(errno));
return -1;
}

nr_func_ksyms = info.nr_jited_ksyms;
if (nr_func_ksyms) {
func_ksyms = malloc(nr_func_ksyms * sizeof(__u64));
if (!func_ksyms) {
p_err("mem alloc failed");
close(fd);
goto err_free;
}
}

nr_func_lens = info.nr_jited_func_lens;
if (nr_func_lens) {
func_lens = malloc(nr_func_lens * sizeof(__u32));
if (!func_lens) {
p_err("mem alloc failed");
close(fd);
info = &info_linear->info;
if (mode == DUMP_JITED) {
if (info->jited_prog_len == 0) {
p_info("no instructions returned");
goto err_free;
}
}

nr_finfo = info.nr_func_info;
finfo_rec_size = info.func_info_rec_size;
if (nr_finfo && finfo_rec_size) {
func_info = malloc(nr_finfo * finfo_rec_size);
if (!func_info) {
p_err("mem alloc failed");
close(fd);
buf = (unsigned char *)(info->jited_prog_insns);
member_len = info->jited_prog_len;
} else { /* DUMP_XLATED */
if (info->xlated_prog_len == 0) {
p_err("error retrieving insn dump: kernel.kptr_restrict set?");
goto err_free;
}
buf = (unsigned char *)info->xlated_prog_insns;
member_len = info->xlated_prog_len;
}

linfo_rec_size = info.line_info_rec_size;
if (info.nr_line_info && linfo_rec_size && info.btf_id) {
nr_linfo = info.nr_line_info;
linfo = malloc(nr_linfo * linfo_rec_size);
if (!linfo) {
p_err("mem alloc failed");
close(fd);
goto err_free;
}
}

jited_linfo_rec_size = info.jited_line_info_rec_size;
if (info.nr_jited_line_info &&
jited_linfo_rec_size &&
info.nr_jited_ksyms &&
info.nr_jited_func_lens &&
info.btf_id) {
nr_jited_linfo = info.nr_jited_line_info;
jited_linfo = malloc(nr_jited_linfo * jited_linfo_rec_size);
if (!jited_linfo) {
p_err("mem alloc failed");
close(fd);
goto err_free;
}
}

memset(&info, 0, sizeof(info));

*member_ptr = ptr_to_u64(buf);
*member_len = buf_size;
info.jited_ksyms = ptr_to_u64(func_ksyms);
info.nr_jited_ksyms = nr_func_ksyms;
info.jited_func_lens = ptr_to_u64(func_lens);
info.nr_jited_func_lens = nr_func_lens;
info.nr_func_info = nr_finfo;
info.func_info_rec_size = finfo_rec_size;
info.func_info = ptr_to_u64(func_info);
info.nr_line_info = nr_linfo;
info.line_info_rec_size = linfo_rec_size;
info.line_info = ptr_to_u64(linfo);
info.nr_jited_line_info = nr_jited_linfo;
info.jited_line_info_rec_size = jited_linfo_rec_size;
info.jited_line_info = ptr_to_u64(jited_linfo);

err = bpf_obj_get_info_by_fd(fd, &info, &len);
close(fd);
if (err) {
p_err("can't get prog info: %s", strerror(errno));
goto err_free;
}

if (*member_len > buf_size) {
p_err("too many instructions returned");
goto err_free;
}

if (info.nr_jited_ksyms > nr_func_ksyms) {
p_err("too many addresses returned");
goto err_free;
}

if (info.nr_jited_func_lens > nr_func_lens) {
p_err("too many values returned");
goto err_free;
}

if (info.nr_func_info != nr_finfo) {
p_err("incorrect nr_func_info %d vs. expected %d",
info.nr_func_info, nr_finfo);
goto err_free;
}

if (info.func_info_rec_size != finfo_rec_size) {
p_err("incorrect func_info_rec_size %d vs. expected %d",
info.func_info_rec_size, finfo_rec_size);
goto err_free;
}

if (linfo && info.nr_line_info != nr_linfo) {
p_err("incorrect nr_line_info %u vs. expected %u",
info.nr_line_info, nr_linfo);
goto err_free;
}

if (info.line_info_rec_size != linfo_rec_size) {
p_err("incorrect line_info_rec_size %u vs. expected %u",
info.line_info_rec_size, linfo_rec_size);
goto err_free;
}

if (jited_linfo && info.nr_jited_line_info != nr_jited_linfo) {
p_err("incorrect nr_jited_line_info %u vs. expected %u",
info.nr_jited_line_info, nr_jited_linfo);
goto err_free;
}

if (info.jited_line_info_rec_size != jited_linfo_rec_size) {
p_err("incorrect jited_line_info_rec_size %u vs. expected %u",
info.jited_line_info_rec_size, jited_linfo_rec_size);
goto err_free;
}

if ((member_len == &info.jited_prog_len &&
info.jited_prog_insns == 0) ||
(member_len == &info.xlated_prog_len &&
info.xlated_prog_insns == 0)) {
p_err("error retrieving insn dump: kernel.kptr_restrict set?");
goto err_free;
}

if (info.btf_id && btf__get_from_id(info.btf_id, &btf)) {
if (info->btf_id && btf__get_from_id(info->btf_id, &btf)) {
p_err("failed to get btf");
goto err_free;
}

if (nr_linfo) {
prog_linfo = bpf_prog_linfo__new(&info);
func_info = (void *)info->func_info;

if (info->nr_line_info) {
prog_linfo = bpf_prog_linfo__new(info);
if (!prog_linfo)
p_info("error in processing bpf_line_info. continue without it.");
}
Expand All @@ -655,47 +520,46 @@ static int do_dump(int argc, char **argv)
goto err_free;
}

n = write(fd, buf, *member_len);
n = write(fd, buf, member_len);
close(fd);
if (n != *member_len) {
if (n != member_len) {
p_err("error writing output file: %s",
n < 0 ? strerror(errno) : "short write");
goto err_free;
}

if (json_output)
jsonw_null(json_wtr);
} else if (member_len == &info.jited_prog_len) {
} else if (mode == DUMP_JITED) {
const char *name = NULL;

if (info.ifindex) {
name = ifindex_to_bfd_params(info.ifindex,
info.netns_dev,
info.netns_ino,
if (info->ifindex) {
name = ifindex_to_bfd_params(info->ifindex,
info->netns_dev,
info->netns_ino,
&disasm_opt);
if (!name)
goto err_free;
}

if (info.nr_jited_func_lens && info.jited_func_lens) {
if (info->nr_jited_func_lens && info->jited_func_lens) {
struct kernel_sym *sym = NULL;
struct bpf_func_info *record;
char sym_name[SYM_MAX_NAME];
unsigned char *img = buf;
__u64 *ksyms = NULL;
__u32 *lens;
__u32 i;

if (info.nr_jited_ksyms) {
if (info->nr_jited_ksyms) {
kernel_syms_load(&dd);
ksyms = (__u64 *) info.jited_ksyms;
ksyms = (__u64 *) info->jited_ksyms;
}

if (json_output)
jsonw_start_array(json_wtr);

lens = (__u32 *) info.jited_func_lens;
for (i = 0; i < info.nr_jited_func_lens; i++) {
lens = (__u32 *) info->jited_func_lens;
for (i = 0; i < info->nr_jited_func_lens; i++) {
if (ksyms) {
sym = kernel_syms_search(&dd, ksyms[i]);
if (sym)
Expand All @@ -707,7 +571,7 @@ static int do_dump(int argc, char **argv)
}

if (func_info) {
record = func_info + i * finfo_rec_size;
record = func_info + i * info->func_info_rec_size;
btf_dumper_type_only(btf, record->type_id,
func_sig,
sizeof(func_sig));
Expand Down Expand Up @@ -744,49 +608,37 @@ static int do_dump(int argc, char **argv)
if (json_output)
jsonw_end_array(json_wtr);
} else {
disasm_print_insn(buf, *member_len, opcodes, name,
disasm_print_insn(buf, member_len, opcodes, name,
disasm_opt, btf, NULL, 0, 0, false);
}
} else if (visual) {
if (json_output)
jsonw_null(json_wtr);
else
dump_xlated_cfg(buf, *member_len);
dump_xlated_cfg(buf, member_len);
} else {
kernel_syms_load(&dd);
dd.nr_jited_ksyms = info.nr_jited_ksyms;
dd.jited_ksyms = (__u64 *) info.jited_ksyms;
dd.nr_jited_ksyms = info->nr_jited_ksyms;
dd.jited_ksyms = (__u64 *) info->jited_ksyms;
dd.btf = btf;
dd.func_info = func_info;
dd.finfo_rec_size = finfo_rec_size;
dd.finfo_rec_size = info->func_info_rec_size;
dd.prog_linfo = prog_linfo;

if (json_output)
dump_xlated_json(&dd, buf, *member_len, opcodes,
dump_xlated_json(&dd, buf, member_len, opcodes,
linum);
else
dump_xlated_plain(&dd, buf, *member_len, opcodes,
dump_xlated_plain(&dd, buf, member_len, opcodes,
linum);
kernel_syms_destroy(&dd);
}

free(buf);
free(func_ksyms);
free(func_lens);
free(func_info);
free(linfo);
free(jited_linfo);
bpf_prog_linfo__free(prog_linfo);
free(info_linear);
return 0;

err_free:
free(buf);
free(func_ksyms);
free(func_lens);
free(func_info);
free(linfo);
free(jited_linfo);
bpf_prog_linfo__free(prog_linfo);
free(info_linear);
return -1;
}

Expand Down

0 comments on commit cae73f2

Please sign in to comment.