perf trace: Add trace__bpf_sys_enter_beauty_map() to prepare for fetching data in BPF

Set up beauty_map, load it to BPF, in such format: if argument No.3 is a
struct of size 32 bytes (of syscall number 114) beauty_map[114][2] = 32;

if argument No.3 is a string (of syscall number 114) beauty_map[114][2] =
1;

if argument No.3 is a buffer, its size is indicated by argument No.4 (of
syscall number 114) beauty_map[114][2] = -4; /* -1 ~ -6, we'll read this
buffer size in BPF  */

Committer notes:

Moved syscall_arg_fmt__cache_btf_struct() from a ifdef
HAVE_LIBBPF_SUPPORT to closer to where it is used, that is ifdef'ed on
HAVE_BPF_SKEL and thus breaks the build when building with
BUILD_BPF_SKEL=0, as detected using 'make -C tools/perf build-test'.

Also add 'struct beauty_map_enter' to tools/perf/util/bpf_skel/augmented_raw_syscalls.bpf.c
as we're using it in this patch, otherwise we get this while trying to
build at this point in the original patch series:

  builtin-trace.c: In function ‘trace__init_syscalls_bpf_prog_array_maps’:
  builtin-trace.c:3725:58: error: ‘struct <anonymous>’ has no member named ‘beauty_map_enter’
   3725 |         int beauty_map_fd = bpf_map__fd(trace->skel->maps.beauty_map_enter);
        |

We also have to take into account syscall_arg_fmt.from_user when telling
the kernel what to copy in the sys_enter generic collector, we don't
want to collect bogus data in buffers that will only be available to us
at sys_exit time, i.e. after the kernel has filled it, so leave this for
when we have such a sys_exit based collector.

Committer testing:

Not wired up yet, so all continues to work, using the existing BPF
collector and userspace beautifiers that are augmentation aware:

  root@number:~# rm -f 987654 ; touch 123456 ; perf trace -e rename* mv 123456 987654
       0.000 ( 0.031 ms): mv/20888 renameat2(olddfd: CWD, oldname: "123456", newdfd: CWD, newname: "987654", flags: NOREPLACE) = 0
  root@number:~# perf trace -e connect,sendto ping -c 1 www.google.com
       0.000 ( 0.014 ms): ping/20892 connect(fd: 5, uservaddr: { .family: LOCAL, path: /run/systemd/resolve/io.systemd.Resolve }, addrlen: 42) = 0
       0.040 ( 0.003 ms): ping/20892 sendto(fd: 5, buff: 0x560b4ff17980, len: 97, flags: DONTWAIT|NOSIGNAL) = 97
       0.480 ( 0.017 ms): ping/20892 sendto(fd: 5, buff: 0x7ffd82d07150, len: 20, addr: { .family: NETLINK }, addr_len: 0xc) = 20
       0.526 ( 0.014 ms): ping/20892 connect(fd: 5, uservaddr: { .family: INET6, port: 0, addr: 2800:3f0:4004:810::2004 }, addrlen: 28) = 0
       0.542 ( 0.002 ms): ping/20892 connect(fd: 5, uservaddr: { .family: UNSPEC }, addrlen: 16)           = 0
       0.544 ( 0.004 ms): ping/20892 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 142.251.135.100 }, addrlen: 16) = 0
       0.559 ( 0.002 ms): ping/20892 connect(fd: 5, uservaddr: { .family: INET, port: 1025, addr: 142.251.135.100 }, addrlen: 16PING www.google.com (142.251.135.100) 56(84) bytes of data.
  ) = 0
       0.589 ( 0.058 ms): ping/20892 sendto(fd: 3, buff: 0x560b4ff11ac0, len: 64, addr: { .family: INET, port: 0, addr: 142.251.135.100 }, addr_len: 0x10) = 64
      45.250 ( 0.029 ms): ping/20892 connect(fd: 5, uservaddr: { .family: LOCAL, path: /run/systemd/resolve/io.systemd.Resolve }, addrlen: 42) = 0
      45.344 ( 0.012 ms): ping/20892 sendto(fd: 5, buff: 0x560b4ff19340, len: 111, flags: DONTWAIT|NOSIGNAL) = 111
  64 bytes from rio09s08-in-f4.1e100.net (142.251.135.100): icmp_seq=1 ttl=49 time=44.4 ms

  --- www.google.com ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 44.361/44.361/44.361/0.000 ms
  root@number:~#

Signed-off-by: Howard Chu <howardchu95@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240815013626.935097-4-howardchu95@gmail.com
Link: https://lore.kernel.org/r/20240824163322.60796-3-howardchu95@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

0 files changed, 0 insertions, 0 deletions