[ Upstream commit 11c1ea6f1a9bc97bf857fd12f72eacb6c69794e2 ]

Optimization level '-Og' offers a reasonable level of optimization while
maintaining fast compilation and a good debugging experience. This patch
tries to make it work.

  $ make DEBUG=1 EXTRA_CFLAGS='-Og'
  bench/epoll-ctl.c: In function ‘do_threads’:
  bench/epoll-ctl.c:274:9: error: ‘ret’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
    return ret;
           ^~~
  ...

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190316080556.3075-4-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 8e2688876c7f7073d925e1f150e86b8ed3338f52 ]

libbpf targets don't explicitly depend on fixdep target, so when
we do 'make -j$(nproc)', there is a high probability, that some
objects will be built before fixdep binary is available.

Fix this by running sub-make; this makes sure that fixdep dependency
is properly accounted for.

For the same issue in perf, see commit abb26210a395 ("perf tools: Force
fixdep compilation at the start of the build").

Before:

$ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/

Auto-detecting system features:
...                        libelf: [ on  ]
...                           bpf: [ on  ]

  HOSTCC   /tmp/bld/fixdep.o
  CC       /tmp/bld/libbpf.o
  CC       /tmp/bld/bpf.o
  CC       /tmp/bld/btf.o
  CC       /tmp/bld/nlattr.o
  CC       /tmp/bld/libbpf_errno.o
  CC       /tmp/bld/str_error.o
  CC       /tmp/bld/netlink.o
  CC       /tmp/bld/bpf_prog_linfo.o
  CC       /tmp/bld/libbpf_probes.o
  CC       /tmp/bld/xsk.o
  HOSTLD   /tmp/bld/fixdep-in.o
  LINK     /tmp/bld/fixdep
  LD       /tmp/bld/libbpf-in.o
  LINK     /tmp/bld/libbpf.a
  LINK     /tmp/bld/libbpf.so
  LINK     /tmp/bld/test_libbpf

$ head /tmp/bld/.libbpf.o.cmd
 # cannot find fixdep (/usr/local/google/home/sdf/src/linux/xxx//fixdep)
 # using basic dep data

/tmp/bld/libbpf.o: libbpf.c /usr/include/stdc-predef.h \
 /usr/include/stdlib.h /usr/include/features.h \
 /usr/include/x86_64-linux-gnu/sys/cdefs.h \
 /usr/include/x86_64-linux-gnu/bits/wordsize.h \
 /usr/include/x86_64-linux-gnu/gnu/stubs.h \
 /usr/include/x86_64-linux-gnu/gnu/stubs-64.h \
 /usr/lib/gcc/x86_64-linux-gnu/7/include/stddef.h \

After:

$ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/

Auto-detecting system features:
...                        libelf: [ on  ]
...                           bpf: [ on  ]

  HOSTCC   /tmp/bld/fixdep.o
  HOSTLD   /tmp/bld/fixdep-in.o
  LINK     /tmp/bld/fixdep
  CC       /tmp/bld/libbpf.o
  CC       /tmp/bld/bpf.o
  CC       /tmp/bld/nlattr.o
  CC       /tmp/bld/btf.o
  CC       /tmp/bld/libbpf_errno.o
  CC       /tmp/bld/str_error.o
  CC       /tmp/bld/netlink.o
  CC       /tmp/bld/bpf_prog_linfo.o
  CC       /tmp/bld/libbpf_probes.o
  CC       /tmp/bld/xsk.o
  LD       /tmp/bld/libbpf-in.o
  LINK     /tmp/bld/libbpf.a
  LINK     /tmp/bld/libbpf.so
  LINK     /tmp/bld/test_libbpf

$ head /tmp/bld/.libbpf.o.cmd
cmd_/tmp/bld/libbpf.o := gcc -Wp,-MD,/tmp/bld/.libbpf.o.d -Wp,-MT,/tmp/bld/libbpf.o -g -Wall -DHAVE_LIBELF_MMAP_SUPPORT -DCOMPAT_NEED_REALLOCARRAY -Wbad-function-cast -Wdeclaration-after-statement -Wformat-security -Wformat-y2k -Winit-self -Wmissing-declarations -Wmissing-prototypes -Wnested-externs -Wno-system-headers -Wold-style-definition -Wpacked -Wredundant-decls -Wshadow -Wstrict-prototypes -Wswitch-default -Wswitch-enum -Wundef -Wwrite-strings -Wformat -Wstrict-aliasing=3 -Werror -Wall -fPIC -I. -I/usr/local/google/home/sdf/src/linux/tools/include -I/usr/local/google/home/sdf/src/linux/tools/arch/x86/include/uapi -I/usr/local/google/home/sdf/src/linux/tools/include/uapi -fvisibility=hidden -D"BUILD_STR(s)=$(pound)s" -c -o /tmp/bld/libbpf.o libbpf.c

source_/tmp/bld/libbpf.o := libbpf.c

deps_/tmp/bld/libbpf.o := \
  /usr/include/stdc-predef.h \
  /usr/include/stdlib.h \
  /usr/include/features.h \
  /usr/include/x86_64-linux-gnu/sys/cdefs.h \
  /usr/include/x86_64-linux-gnu/bits/wordsize.h \

Fixes: 7c422f557266 ("tools build: Build fixdep helper from perf and basic libs")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Commit c3494801cd17 ("bpf: check pending signals while
verifying programs") makes it possible for the BPF_PROG_LOAD
to fail with EAGAIN. Retry unconditionally in this case.

Fixes: c3494801cd17 ("bpf: check pending signals while verifying programs")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

We build test_libbpf with CXX to make sure linking against C++ works.

$ make -s -C tools/lib/bpf
$ git status -sb
? tools/lib/bpf/test_libbpf
$ make -s -C tools/testing/selftests/bpf
$ git status -sb
? tools/lib/bpf/test_libbpf
? tools/testing/selftests/bpf/test_libbpf

Fixes: 8c4905b995c6 ("libbpf: make sure bpf headers are c++ include-able")
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Given this came up couple of times, add a note to libbpf's readme
about the semi-automated mirror for a stand-alone build which is
officially managed by BPF folks. While at it, also explicitly state
the libbpf license in the readme file.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This patch fixes a memory leak in libbpf by freeing up line_info
member of struct bpf_program while unloading a program.

Fixes: 3d65014146c6 ("bpf: libbpf: Add btf_line_info support to libbpf")
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

kernel can provide the func_info and line_info even
it fails the btf_dump_raw_ok() test because they don't contain
kernel address.  This patch removes the corresponding '== 0'
test.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Rename all occurances of *_info_cnt field access
to nr_*_info in tools directory.

The local variables finfo_cnt, linfo_cnt and jited_linfo_cnt
in function do_dump() of tools/bpf/bpftool/prog.c are also
changed to nr_finfo, nr_linfo and nr_jited_linfo to
keep naming convention consistent.

Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This patch adds print bpf_line_info function in 'prog dump jitted'
and 'prog dump xlated':

[root@arch-fb-vm1 bpf]# ~/devshare/fb-kernel/linux/tools/bpf/bpftool/bpftool prog dump jited pinned /sys/fs/bpf/test_btf_haskv
[...]
int test_long_fname_2(struct dummy_tracepoint_args * arg):
bpf_prog_44a040bf25481309_test_long_fname_2:
; static int test_long_fname_2(struct dummy_tracepoint_args *arg)
   0:	push   %rbp
   1:	mov    %rsp,%rbp
   4:	sub    $0x30,%rsp
   b:	sub    $0x28,%rbp
   f:	mov    %rbx,0x0(%rbp)
  13:	mov    %r13,0x8(%rbp)
  17:	mov    %r14,0x10(%rbp)
  1b:	mov    %r15,0x18(%rbp)
  1f:	xor    %eax,%eax
  21:	mov    %rax,0x20(%rbp)
  25:	xor    %esi,%esi
; int key = 0;
  27:	mov    %esi,-0x4(%rbp)
; if (!arg->sock)
  2a:	mov    0x8(%rdi),%rdi
; if (!arg->sock)
  2e:	cmp    $0x0,%rdi
  32:	je     0x0000000000000070
  34:	mov    %rbp,%rsi
; counts = bpf_map_lookup_elem(&btf_map, &key);
  37:	add    $0xfffffffffffffffc,%rsi
  3b:	movabs $0xffff8881139d7480,%rdi
  45:	add    $0x110,%rdi
  4c:	mov    0x0(%rsi),%eax
  4f:	cmp    $0x4,%rax
  53:	jae    0x000000000000005e
  55:	shl    $0x3,%rax
  59:	add    %rdi,%rax
  5c:	jmp    0x0000000000000060
  5e:	xor    %eax,%eax
; if (!counts)
  60:	cmp    $0x0,%rax
  64:	je     0x0000000000000070
; counts->v6++;
  66:	mov    0x4(%rax),%edi
  69:	add    $0x1,%rdi
  6d:	mov    %edi,0x4(%rax)
  70:	mov    0x0(%rbp),%rbx
  74:	mov    0x8(%rbp),%r13
  78:	mov    0x10(%rbp),%r14
  7c:	mov    0x18(%rbp),%r15
  80:	add    $0x28,%rbp
  84:	leaveq
  85:	retq
[...]

With linum:
[root@arch-fb-vm1 bpf]# ~/devshare/fb-kernel/linux/tools/bpf/bpftool/bpftool prog dump jited pinned /sys/fs/bpf/test_btf_haskv linum
int _dummy_tracepoint(struct dummy_tracepoint_args * arg):
bpf_prog_b07ccb89267cf242__dummy_tracepoint:
; return test_long_fname_1(arg); [file:/data/users/kafai/fb-kernel/linux/tools/testing/selftests/bpf/test_btf_haskv.c line_num:54 line_col:9]
   0:	push   %rbp
   1:	mov    %rsp,%rbp
   4:	sub    $0x28,%rsp
   b:	sub    $0x28,%rbp
   f:	mov    %rbx,0x0(%rbp)
  13:	mov    %r13,0x8(%rbp)
  17:	mov    %r14,0x10(%rbp)
  1b:	mov    %r15,0x18(%rbp)
  1f:	xor    %eax,%eax
  21:	mov    %rax,0x20(%rbp)
  25:	callq  0x000000000000851e
; return test_long_fname_1(arg); [file:/data/users/kafai/fb-kernel/linux/tools/testing/selftests/bpf/test_btf_haskv.c line_num:54 line_col:2]
  2a:	xor    %eax,%eax
  2c:	mov    0x0(%rbp),%rbx
  30:	mov    0x8(%rbp),%r13
  34:	mov    0x10(%rbp),%r14
  38:	mov    0x18(%rbp),%r15
  3c:	add    $0x28,%rbp
  40:	leaveq
  41:	retq
[...]

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This patch adds bpf_line_info support to libbpf:
1) Parsing the line_info sec from ".BTF.ext"
2) Relocating the line_info.  If the main prog *_info relocation
   fails, it will ignore the remaining subprog line_info and continue.
   If the subprog *_info relocation fails, it will bail out.
3) BPF_PROG_LOAD a prog with line_info

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>