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Commit Graph

63 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo
e051c2f698 perf augmented_raw_syscalls: Reduce perf_event_output() boilerplate
Add a augmented__output() helper to reduce the boilerplate of sending
the augmented tracepoint to the PERF_EVENT_ARRAY BPF map associated with
the bpf-output event used to communicate with the userspace perf trace
tool.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-ln99gt0j4fv0kw0778h6vphm@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-08-26 11:58:29 -03:00
Arnaldo Carvalho de Melo
c265784de7 perf augmented_raw_syscalls: Introduce helper to get the scratch space
We need more than the BPF stack can give us to format the
raw_syscalls:sys_enter augmented tracepoint, so we use a PERCPU_ARRAY
map for that, use a helper to shorten the sequence to access that area.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-08-26 11:58:29 -03:00
Arnaldo Carvalho de Melo
01128065ca perf augmented_raw_syscalls: Postpone tmp map lookup to after pid_filter
No sense in doing that lookup before figuring out if it will be used,
i.e. if the pid is being filtered that tmp space lookup will be useless.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-o74yggieorucfg4j74tb6rta@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-08-26 11:58:29 -03:00
Arnaldo Carvalho de Melo
2ad926db78 perf augmented_raw_syscalls: Rename augmented_filename to augmented_arg
Because it is not used only for strings, we already use it for sockaddr
structs and will use it for all other types.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-w9nkt3tvmyn5i4qnwng3ap1k@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-08-26 11:58:29 -03:00
Arnaldo Carvalho de Melo
cfa9ac73d6 perf trace beauty: Add BPF augmenter for the 'rename' syscall
I.e. two strings:

  # perf trace -e rename
  systemd/1 rename("/run/systemd/units/.#invocation:dnf-makecache.service970761b7f2840dcc", "/run/systemd/units/invocation:dnf-makecache.service") = 0
  systemd-journa/715 rename("/run/systemd/journal/streams/.#9:17539785BJDblc", "/run/systemd/journal/streams/9:17539785") = 0
  mv/1936 rename("/tmp/build/perf/fd/.array.o.tmp", "/tmp/build/perf/fd/.array.o.cmd") = 0
  sh/1949 rename("/tmp/build/perf/.cpu.o.tmp", "/tmp/build/perf/.cpu.o.cmd") = 0
  mv/1954 rename("/tmp/build/perf/fs/.tracing_path.o.tmp", "/tmp/build/perf/fs/.tracing_path.o.cmd") = 0
  mv/1963 rename("/tmp/build/perf/common-cmds.h+", "/tmp/build/perf/common-cmds.h") = 0
  :1975/1975 rename("/tmp/build/perf/.exec-cmd.o.tmp", "/tmp/build/perf/.exec-cmd.o.cmd") = 0
  mv/1979 rename("/tmp/build/perf/fs/.fs.o.tmp", "/tmp/build/perf/fs/.fs.o.cmd") = 0
  mv/2005 rename("/tmp/build/perf/.debug.o.tmp", "/tmp/build/perf/.debug.o.cmd") = 0
  mv/2012 rename("/tmp/build/perf/.str_error_r.o.tmp", "/tmp/build/perf/.str_error_r.o.cmd") = 0
  mv/2019 rename("/tmp/build/perf/.help.o.tmp", "/tmp/build/perf/.help.o.cmd") = 0
  mv/2031 rename("/tmp/build/perf/.trace-seq.o.tmp", "/tmp/build/perf/.trace-seq.o.cmd") = 0
  make/2038  ... [continued]: rename())             = 0
  :2038/2038 rename("/tmp/build/perf/.event-plugin.o.tmp", "/tmp/build/perf/.event-plugin.o.cmd") ...
  ar/2035 rename("/tmp/build/perf/stzwBX3a", "/tmp/build/perf/libapi.a") = 0
  mv/2051 rename("/tmp/build/perf/.parse-utils.o.tmp", "/tmp/build/perf/.parse-utils.o.cmd") = 0
  mv/2069 rename("/tmp/build/perf/.subcmd-config.o.tmp", "/tmp/build/perf/.subcmd-config.o.cmd") = 0
  make/2080 rename("/tmp/build/perf/.parse-filter.o.tmp", "/tmp/build/perf/.parse-filter.o.cmd") = 0
  mv/2099 rename("/tmp/build/perf/.pager.o.tmp", "/tmp/build/perf/.pager.o.cmd") = 0
  :2124/2124 rename("/tmp/build/perf/.sigchain.o.tmp", "/tmp/build/perf/.sigchain.o.cmd") = 0
  make/2140 rename("/tmp/build/perf/.event-parse.o.tmp", "/tmp/build/perf/.event-parse.o.cmd") = 0
  mv/2164 rename("/tmp/build/perf/.kbuffer-parse.o.tmp", "/tmp/build/perf/.kbuffer-parse.o.cmd") = 0
  sh/2174 rename("/tmp/build/perf/.run-command.o.tmp", "/tmp/build/perf/.run-command.o.cmd") = 0
  mv/2190 rename("/tmp/build/perf/.tep_strerror.o.tmp", "/tmp/build/perf/.tep_strerror.o.cmd") = 0
  :2261/2261 rename("/tmp/build/perf/.event-parse-api.o.tmp", "/tmp/build/perf/.event-parse-api.o.cmd") = 0
  :2480/2480 rename("/tmp/build/perf/stLv3kG2", "/tmp/build/perf/libtraceevent.a") = 0
  ^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-6hh2rl27uri6gsxhmk6q3hx5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:42 -03:00
Arnaldo Carvalho de Melo
3c475bc021 perf trace beauty: Beautify 'sendto's sockaddr arg
By just writing the collector in the augmented_raw_syscalls.c BPF
program:

  # perf trace -e sendto
  <SNIP>
  ping/23492 sendto(3, 0x56253bbef700, 64, NONE, { .family: PF_INET, port: 0, addr: 10.10.161.32 }, 0x10) = 64
  ping/23492 sendto(3, 0x56253bbef700, 64, NONE, { .family: PF_INET, port: 0, addr: 10.10.161.32 }, 0x10) = 64
  ping/23492 sendto(3, 0x56253bbef700, 64, NONE, { .family: PF_INET, port: 0, addr: 10.10.161.32 }, 0x10) = 64
  ping/23492 sendto(3, 0x56253bbef700, 64, NONE, { .family: PF_INET, port: 0, addr: 10.10.161.32 }, 0x10) = 64
  Socket Thread/3573 sendto(247, 0x7fb32d49c000, 120, NONE, { .family: PF_UNSPEC }, NULL) = 120
  DNS Res~er #18/11374 sendto(242, 0x7fb342cfe420, 20, NONE, { .family: PF_NETLINK }, 0xc) = 20
  DNS Res~er #18/11374 sendto(242, 0x7fb342cfcca0, 42, MSG_NOSIGNAL, { .family: PF_UNSPEC }, NULL) = 42
  DNS Res~er #18/11374 sendto(242, 0x7fb342cfcccc, 42, MSG_NOSIGNAL, { .family: PF_UNSPEC }, NULL) = 42
  ping/23492 sendto(3, 0x56253bbef700, 64, NONE, { .family: PF_INET, port: 0, addr: 10.10.161.32 }, 0x10) = 64
  Socket Thread/3573 sendto(242, 0x7fb308bb1c08, 296, NONE, { .family: PF_UNSPEC }, NULL) = 296
  ping/23492 sendto(3, 0x56253bbef700, 64, NONE, { .family: PF_INET, port: 0, addr: 10.10.161.32 }, 0x10) = 64
  ping/23492 sendto(3, 0x56253bbef700, 64, NONE, { .family: PF_INET, port: 0, addr: 10.10.161.32 }, 0x10) = 64
  ping/23492 sendto(3, 0x56253bbef700, 64, NONE, { .family: PF_INET, port: 0, addr: 10.10.161.32 }, 0x10) = 64
  ping/23492 sendto(3, 0x56253bbef700, 64, NONE, { .family: PF_INET, port: 0, addr: 10.10.161.32 }, 0x10) = 64
  ^C
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-p0l0rlvq19v5zf8qc2x2itow@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:41 -03:00
Arnaldo Carvalho de Melo
212b9ab677 perf augmented_raw_syscalls: Augment sockaddr arg in 'connect'
We already had a beautifier for an augmented sockaddr payload, but that
was when we were hooking on each syscalls:sys_enter_foo tracepoints,
since now we're almost doing that by doing a tail call from
raw_syscalls:sys_enter, its almost the same, we can reuse it straight
away.

  # perf trace -e connec* ssh www.bla.com
  connect(3</var/lib/sss/mc/passwd>, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory)
  connect(3</var/lib/sss/mc/passwd>, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory)
  connect(4<socket:[16604782]>, { .family: PF_LOCAL, path: /var/lib/sss/pipes/nss }, 0x6e) = 0
  connect(7, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory)
  connect(7, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory)
  connect(5</etc/hosts>, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory)
  connect(5</etc/hosts>, { .family: PF_LOCAL, path: /var/run/nscd/socket }, 0x6e) = -1 ENOENT (No such file or directory)
  connect(5</etc/hosts>, { .family: PF_INET, port: 53, addr: 192.168.44.1 }, 0x10) = 0
  connect(5</etc/hosts>, { .family: PF_INET, port: 22, addr: 146.112.61.108 }, 0x10) = 0
  connect(5</etc/hosts>, { .family: PF_INET6, port: 22, addr: ::ffff:146.112.61.108 }, 0x1c) = 0
  ^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-5xkrbcpjsgnr3zt1aqdd7nvc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:41 -03:00
Arnaldo Carvalho de Melo
6f56367493 perf augmented_raw_syscalls: Rename augmented_args_filename to augmented_args_payload
It'll get other stuff in there than just filenames, starting with
sockaddr for 'connect' and 'bind'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-bsexidtsn91ehdpzcd6n5fm9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:41 -03:00
Arnaldo Carvalho de Melo
8d5da2649d perf augmented_raw_syscalls: Support copying two string syscall args
Starting with the renameat and renameat2 syscall, that both receive as
second and fourth parameters a pathname:

  # perf trace -e rename* mv one ANOTHER
  LLVM: dumping /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
  mv: cannot stat 'one': No such file or directory
  renameat2(AT_FDCWD, "one", AT_FDCWD, "ANOTHER", RENAME_NOREPLACE) = -1 ENOENT (No such file or directory)
  #

Since the per CPU scratch buffer map has space for two maximum sized
pathnames, the verifier is satisfied that there will be no overrun.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-x2uboyg5kx2wqeru288209b6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:41 -03:00
Arnaldo Carvalho de Melo
bf134ca6c8 perf augmented_raw_syscalls: Switch to using BPF_MAP_TYPE_PROG_ARRAY
Trying to control what arguments to copy, which ones were strings, etc
all from userspace via maps went nowhere, lots of difficulties to get
the verifier satisfied, so use what the fine BPF guys designed for such
a syscall handling mechanism: bpf_tail_call + BPF_MAP_TYPE_PROG_ARRAY.

The series leading to this should have explained it thoroughly, but the
end result, explained via gdb should help understand this:

  Breakpoint 1, syscall_arg__scnprintf_filename (bf=0xc002b1 "", size=2031, arg=0x7fffffff7970) at builtin-trace.c:1268
  1268	{
  (gdb) n
  1269		unsigned long ptr = arg->val;
  (gdb) n
  1271		if (arg->augmented.args)
  (gdb) n
  1272			return syscall_arg__scnprintf_augmented_string(arg, bf, size);
  (gdb) s
  syscall_arg__scnprintf_augmented_string (arg=0x7fffffff7970, bf=0xc002b1 "", size=2031) at builtin-trace.c:1251
  1251	{
  (gdb) n
  1252		struct augmented_arg *augmented_arg = arg->augmented.args;
  (gdb) n
  1253		size_t printed = scnprintf(bf, size, "\"%.*s\"", augmented_arg->size, augmented_arg->value);
  (gdb) n
  1258		int consumed = sizeof(*augmented_arg) + augmented_arg->size;
  (gdb) p bf
  $1 = 0xc002b1 "\"/etc/ld.so.cache\""
  (gdb) bt
  #0  syscall_arg__scnprintf_augmented_string (arg=0x7fffffff7970, bf=0xc002b1 "\"/etc/ld.so.cache\"", size=2031) at builtin-trace.c:1258
  #1  0x0000000000492634 in syscall_arg__scnprintf_filename (bf=0xc002b1 "\"/etc/ld.so.cache\"", size=2031, arg=0x7fffffff7970) at builtin-trace.c:1272
  #2  0x0000000000493cd7 in syscall__scnprintf_val (sc=0xc0de68, bf=0xc002b1 "\"/etc/ld.so.cache\"", size=2031, arg=0x7fffffff7970, val=140737354091036) at builtin-trace.c:1689
  #3  0x000000000049404f in syscall__scnprintf_args (sc=0xc0de68, bf=0xc002a7 "AT_FDCWD, \"/etc/ld.so.cache\"", size=2041, args=0x7ffff6cbf1ec "\234\377\377\377", augmented_args=0x7ffff6cbf21c, augmented_args_size=28, trace=0x7fffffffa170,
      thread=0xbff940) at builtin-trace.c:1756
  #4  0x0000000000494a97 in trace__sys_enter (trace=0x7fffffffa170, evsel=0xbe1900, event=0x7ffff6cbf1a0, sample=0x7fffffff7b00) at builtin-trace.c:1975
  #5  0x0000000000496ff1 in trace__handle_event (trace=0x7fffffffa170, event=0x7ffff6cbf1a0, sample=0x7fffffff7b00) at builtin-trace.c:2685
  #6  0x0000000000497edb in __trace__deliver_event (trace=0x7fffffffa170, event=0x7ffff6cbf1a0) at builtin-trace.c:3029
  #7  0x000000000049801e in trace__deliver_event (trace=0x7fffffffa170, event=0x7ffff6cbf1a0) at builtin-trace.c:3056
  #8  0x00000000004988de in trace__run (trace=0x7fffffffa170, argc=2, argv=0x7fffffffd660) at builtin-trace.c:3258
  #9  0x000000000049c2d3 in cmd_trace (argc=2, argv=0x7fffffffd660) at builtin-trace.c:4220
  #10 0x00000000004dcb6c in run_builtin (p=0xa18e00 <commands+576>, argc=5, argv=0x7fffffffd660) at perf.c:304
  #11 0x00000000004dcdd9 in handle_internal_command (argc=5, argv=0x7fffffffd660) at perf.c:356
  #12 0x00000000004dcf20 in run_argv (argcp=0x7fffffffd4bc, argv=0x7fffffffd4b0) at perf.c:400
  #13 0x00000000004dd28c in main (argc=5, argv=0x7fffffffd660) at perf.c:522
  (gdb)
  (gdb) continue
  Continuing.
  openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3

Now its a matter of automagically assigning the BPF programs copying
syscall arg pointers to functions that are "open"-like (i.e. that need
only the first syscall arg copied as a string), or "openat"-like (2nd
arg, etc).

End result in tool output:

  # perf trace -e open* ls /tmp/notthere
  LLVM: dumping /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
  openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/lib64/libselinux.so.1", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/lib64/libcap.so.2", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/lib64/libpcre2-8.so.0", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/lib64/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/lib64/libpthread.so.0", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/usr/share/locale/locale.alias", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/usr/share/locale/en_US.UTF-8/LC_MESSAGES/coreutils.mo", O_RDONLY) = ls: cannot access '/tmp/notthere'-1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en_US.utf8/LC_MESSAGES/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en_US/LC_MESSAGES/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en.UTF-8/LC_MESSAGES/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en.utf8/LC_MESSAGES/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en/LC_MESSAGES/coreutils.mo", O_RDONLY: No such file or directory) =
  -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en_US.UTF-8/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en_US.utf8/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en_US/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en.UTF-8/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en.utf8/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en/LC_MESSAGES/libc.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-snc7ry99cl6r0pqaspjim98x@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:41 -03:00
Arnaldo Carvalho de Melo
236dd58388 perf augmented_raw_syscalls: Add handler for "openat"
I.e. for a syscall that has its second argument being a string, its
difficult these days to find 'open' being used in the wild :-)

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-yf3kbzirqrukd3fb2sp5qx4p@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:41 -03:00
Arnaldo Carvalho de Melo
3803a22931 perf trace: Put the per-syscall entry/exit prog_array BPF map infrastructure in place
I.e. look for "syscalls_sys_enter" and "syscalls_sys_exit" BPF maps of
type PROG_ARRAY and populate it with the handlers as specified per
syscall, for now only 'open' is wiring it to something, in time all
syscalls that need to copy arguments entering a syscall or returning
from one will set these to the right handlers, reusing when possible
pre-existing ones.

Next step is to use bpf_tail_call() into that.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-t0p4u43i9vbpzs1xtowna3gb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:41 -03:00
Arnaldo Carvalho de Melo
6ff8fff456 perf trace: Allow specifying the bpf prog to augment specific syscalls
This is a step in the direction of being able to use a
BPF_MAP_TYPE_PROG_ARRAY to handle syscalls that need to copy pointer
payloads in addition to the raw tracepoint syscall args.

There is a first example in
tools/perf/examples/bpf/augmented_raw_syscalls.c for the 'open' syscall.

Next step is to introduce the prog array map and use this 'open'
augmenter, then use that augmenter in other syscalls that also only copy
the first arg as a string, and then show how to use with a syscall that
reads more than one filename, like 'rename', etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-pys4v57x5qqrybb4cery2mc8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:41 -03:00
Arnaldo Carvalho de Melo
5834da7f10 perf trace: Add BPF handler for unaugmented syscalls
Will be used to assign to syscalls that don't need augmentation, i.e.
those with just integer args.

All syscalls will be in a BPF_MAP_TYPE_PROG_ARRAY, and the
bpf_tail_call() keyed by the syscall id will either find nothing in
place, which means the syscall is being filtered, or a function that
will either add things like filenames to the ring buffer, right after
the raw syscall args, or be this unaugmented handler that will just
return 1, meaning don't filter the original
raw_syscalls:sys_{enter,exit} tracepoint.

For now it is not really being used, this is just leg work to break the
patch into smaller pieces.

It introduces a trace__find_bpf_program_by_title() helper that in turn
uses libbpf's bpf_object__find_program_by_title() on the BPF object with
the __augmented_syscalls__ map. "title" is how libbpf calls the SEC()
argument for functions, i.e. the ELF section that follows a convention
to specify what BPF program (a function with this SEC() marking) should
be connected to which tracepoint, kprobes, etc.

In perf anything that is of the form SEC("sys:event_name") will be
connected to that tracepoint by perf's BPF loader.

In this case its something that will be bpf_tail_call()ed from either
the "raw_syscalls:sys_enter" or "raw_syscall:sys_exit" tracepoints, so
its named "!raw_syscalls:unaugmented" to convey that idea, i.e. its not
going to be directly attached to a tracepoint, thus it starts with a
"!".

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-meucpjx2u0slpkayx56lxqq6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29 18:34:41 -03:00
Arnaldo Carvalho de Melo
602bce09fb perf augmented_raw_syscalls: Move reading filename to the loop
Almost there, next step is to copy more than one filename payload.

Probably to read syscall arg structs, etc we'll need just a variation of
this that will decide what to use, if probe_read_str() or plain
probe_read for structs, i.e. fixed size.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-uf6u0pld6xe4xuo16f04owlz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-06-05 09:48:55 -03:00
Arnaldo Carvalho de Melo
deaf4da48a perf augmented_raw_syscalls: Change helper to consider just the augmented_filename part
So that we can use it for multiple args, baby steps not to step into the
verifier toes.

In the process make sure we handle -EFAULT from bpf_prog_read_str(), as
this really is needed now that we'll handle more than one augmented
argument, i.e. if there is failure, then we have the argument that fails
have:

  (size = 0, err = -EFAULT, value = [] )

followed by the next, lets say that worked for a second pathname:

  (size = 4, err = 0, value = "/tmp" )

So we can skip the first while telling the user about the problem and
then process the second.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-deyvqi39um6gp6hux6jovos8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-06-05 09:48:54 -03:00
Arnaldo Carvalho de Melo
0c95a7ff76 perf augmented_raw_syscalls: Move the probe_read_str to a separate function
One more step into copying multiple filenames to support syscalls like
rename*.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-xdqtjexdyp81oomm1rkzeifl@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-06-05 09:47:58 -03:00
Arnaldo Carvalho de Melo
4cae8675ea perf augmented_raw_syscalls: Tell which args are filenames and how many bytes to copy
Since we know what args are strings from reading the syscall
descriptions in tracefs and also already mark such args to be beautified
using the syscall_arg__scnprintf_filename() helper, all we need is to
fill in this info in the 'syscalls' BPF map we were using to state which
syscalls the user is interested in, i.e. the syscall filter.

Right now just set that with PATH_MAX and unroll the syscall arg in the
BPF program, as the verifier isn't liking something clang generates when
unrolling the loop.

This also makes the augmented_raw_syscalls.c program support all arches,
since we removed that set of defines with the hard coded syscall
numbers, all should be automatically set for all arches, with the
syscall id mapping done correcly.

Doing baby steps here, i.e. just the first string arg for a syscall is
printed, syscalls with more than one, say, the various rename* syscalls,
need further work, but lets get first something that the BPF verifier
accepts before increasing the complexity

To test it, something like:

 # perf trace -e string -e /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.c

With:

  # cat ~/.perfconfig
  [llvm]
	dump-obj = true
	clang-opt = -g
  [trace]
	#add_events = /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.c
	show_zeros = yes
	show_duration = no
	no_inherit = yes
	show_timestamp = no
	show_arg_names = no
	args_alignment = 40
	show_prefix = yes
  #

That commented add_events line is needed for developing this
augmented_raw_syscalls.c BPF program, as if we add it via the
'add_events' mechanism so as to shorten the 'perf trace' command lines,
then we end up not setting up the -v option which precludes us having
access to the bpf verifier log :-\

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-dn863ya0cbsqycxuy0olvbt1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-06-05 09:47:58 -03:00
Arnaldo Carvalho de Melo
693bd3949b perf trace: Beautify 'fspick' arguments
Use existing beautifiers for the first 2 args (dfd, path) and wire up
the recently introduced fspick flags table generator.

Now it should be possible to just use:

   perf trace -e fspick

As root and see all move_mount syscalls with its args beautified, either
using the vfs_getname perf probe method or using the
augmented_raw_syscalls.c eBPF helper to get the pathnames, the other
args should work in all cases, i.e. all that is needed can be obtained
directly from the raw_syscalls:sys_enter tracepoint args.

  # cat sys_fspick.c
  #define _GNU_SOURCE        /* See feature_test_macros(7) */
  #include <unistd.h>
  #include <sys/syscall.h>   /* For SYS_xxx definitions */
  #include <fcntl.h>

  #define __NR_fspick 433

  #define FSPICK_CLOEXEC          0x00000001
  #define FSPICK_SYMLINK_NOFOLLOW 0x00000002
  #define FSPICK_NO_AUTOMOUNT     0x00000004
  #define FSPICK_EMPTY_PATH       0x00000008

  static inline int sys_fspick(int fd, const char *path, int flags)
  {
  	syscall(__NR_fspick, fd, path, flags);
  }

  int main(int argc, char *argv[])
  {
  	int flags = 0, fd = 0;

  	open("/foo", 0);
  	sys_fspick(fd++, "/foo1", flags);
  	flags |= FSPICK_CLOEXEC;
  	sys_fspick(fd++, "/foo2", flags);
  	flags |= FSPICK_SYMLINK_NOFOLLOW;
  	sys_fspick(fd++, "/foo3", flags);
  	flags |= FSPICK_NO_AUTOMOUNT;
  	sys_fspick(fd++, "/foo4", flags);
  	flags |= FSPICK_EMPTY_PATH;
  	return sys_fspick(fd++, "/foo5", flags);
  }
  # perf trace -e fspick ./sys_fspick
  LLVM: dumping /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
  fspick(0, "/foo1", 0)                   = -1 ENOENT (No such file or directory)
  fspick(1, "/foo2", FSPICK_CLOEXEC)      = -1 ENOENT (No such file or directory)
  fspick(2, "/foo3", FSPICK_CLOEXEC|FSPICK_SYMLINK_NOFOLLOW) = -1 ENOENT (No such file or directory)
  fspick(3, "/foo4", FSPICK_CLOEXEC|FSPICK_SYMLINK_NOFOLLOW|FSPICK_NO_AUTOMOUNT) = -1 ENOENT (No such file or directory)
  fspick(4, "/foo5", FSPICK_CLOEXEC|FSPICK_SYMLINK_NOFOLLOW|FSPICK_NO_AUTOMOUNT|FSPICK_EMPTY_PATH) = -1 ENOENT (No such file or directory)
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-erau5xjtt8wvgnhvdbchstuk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-05-28 18:37:42 -03:00
Arnaldo Carvalho de Melo
566e30229e perf trace: Beautify 'move_mount' arguments
Use existing beautifiers for the first 4 args (to/from fds, pathnames)
and wire up the recently introduced move_mount flags table generator.

Now it should be possible to just use:

      perf trace -e move_mount

As root and see all move_mount syscalls with its args beautified, except
for the filenames, that need work in the augmented_raw_syscalls.c eBPF
helper to pass more than one, see comment in the
augmented_raw_syscalls.c source code, the other args should work in all
cases, i.e. all that is needed can be obtained directly from the
raw_syscalls:sys_enter tracepoint args.

Running without the strace "skin" (.perfconfig setting output formatting
switches to look like strace output + BPF to collect strings, as we
still need to support collecting multiple string args for the same
syscall, like with move_mount):

  # cat sys_move_mount.c
  #define _GNU_SOURCE         /* See feature_test_macros(7) */
  #include <unistd.h>
  #include <sys/syscall.h>   /* For SYS_xxx definitions */

  #define __NR_move_mount 429

  #define MOVE_MOUNT_F_SYMLINKS		0x00000001 /* Follow symlinks on from path */
  #define MOVE_MOUNT_F_AUTOMOUNTS		0x00000002 /* Follow automounts on from path */
  #define MOVE_MOUNT_F_EMPTY_PATH		0x00000004 /* Empty from path permitted */
  #define MOVE_MOUNT_T_SYMLINKS		0x00000010 /* Follow symlinks on to path */
  #define MOVE_MOUNT_T_AUTOMOUNTS		0x00000020 /* Follow automounts on to path */
  #define MOVE_MOUNT_T_EMPTY_PATH		0x00000040 /* Empty to path permitted */

  static inline int sys_move_mount(int from_fd, const char *from_pathname,
  				 int to_fd, const char *to_pathname,
  				 int flags)
  {
  	  syscall(__NR_move_mount, from_fd, from_pathname, to_fd, to_pathname, flags);
  }

  int main(int argc, char *argv[])
  {
  	  int flags = 0, from_fd = 0, to_fd = 100;

  	  sys_move_mount(from_fd++, "/foo", to_fd++, "bar", flags);
  	  flags |= MOVE_MOUNT_F_SYMLINKS;
  	  sys_move_mount(from_fd++, "/foo1", to_fd++, "bar1", flags);
          flags |= MOVE_MOUNT_F_AUTOMOUNTS;
  	  sys_move_mount(from_fd++, "/foo2", to_fd++, "bar2", flags);
          flags |= MOVE_MOUNT_F_EMPTY_PATH;
  	  sys_move_mount(from_fd++, "/foo3", to_fd++, "bar3", flags);
          flags |= MOVE_MOUNT_T_SYMLINKS;
  	  sys_move_mount(from_fd++, "/foo4", to_fd++, "bar4", flags);
          flags |= MOVE_MOUNT_T_AUTOMOUNTS;
  	  sys_move_mount(from_fd++, "/foo5", to_fd++, "bar5", flags);
          flags |= MOVE_MOUNT_T_EMPTY_PATH;
  	  return sys_move_mount(from_fd++, "/foo6", to_fd++, "bar6", flags);
  }
  # mv ~/.perfconfig  ~/.perfconfig.OFF
  # perf trace -e move_mount ./sys_move_mount
       0.000 ( 0.009 ms): sys_move_mount/28971 move_mount(from_pathname: 0x402010, to_dfd: 100, to_pathname: 0x402015) = -1 ENOENT (No such file or directory)
       0.011 ( 0.003 ms): sys_move_mount/28971 move_mount(from_dfd: 1, from_pathname: 0x40201e, to_dfd: 101, to_pathname: 0x402019, flags: F_SYMLINKS) = -1 ENOENT (No such file or directory)
       0.016 ( 0.002 ms): sys_move_mount/28971 move_mount(from_dfd: 2, from_pathname: 0x402029, to_dfd: 102, to_pathname: 0x402024, flags: F_SYMLINKS|F_AUTOMOUNTS) = -1 ENOENT (No such file or directory)
       0.020 ( 0.002 ms): sys_move_mount/28971 move_mount(from_dfd: 3, from_pathname: 0x402034, to_dfd: 103, to_pathname: 0x40202f, flags: F_SYMLINKS|F_AUTOMOUNTS|F_EMPTY_PATH) = -1 ENOENT (No such file or directory)
       0.023 ( 0.002 ms): sys_move_mount/28971 move_mount(from_dfd: 4, from_pathname: 0x40203f, to_dfd: 104, to_pathname: 0x40203a, flags: F_SYMLINKS|F_AUTOMOUNTS|F_EMPTY_PATH|T_SYMLINKS) = -1 ENOENT (No such file or directory)
       0.027 ( 0.002 ms): sys_move_mount/28971 move_mount(from_dfd: 5, from_pathname: 0x40204a, to_dfd: 105, to_pathname: 0x402045, flags: F_SYMLINKS|F_AUTOMOUNTS|F_EMPTY_PATH|T_SYMLINKS|T_AUTOMOUNTS) = -1 ENOENT (No such file or directory)
       0.031 ( 0.017 ms): sys_move_mount/28971 move_mount(from_dfd: 6, from_pathname: 0x402055, to_dfd: 106, to_pathname: 0x402050, flags: F_SYMLINKS|F_AUTOMOUNTS|F_EMPTY_PATH|T_SYMLINKS|T_AUTOMOUNTS|T_EMPTY_PATH) = -1 ENOENT (No such file or directory)
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-83rim8g4k0s4gieieh5nnlck@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-05-28 18:37:42 -03:00
Arnaldo Carvalho de Melo
8a70c6b162 perf augmented_raw_syscalls: Fix up comment
Cut'n'paste error, the second comment is about the syscalls that have as
its second arg a string.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-zo5s6rloy42u41acsf6q3pvi@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-05-28 18:37:42 -03:00
Arnaldo Carvalho de Melo
59f3bd7802 perf augmented_raw_syscalls: Use a PERCPU_ARRAY map to copy more string bytes
The previous method, copying to the BPF stack limited us in how many
bytes we could copy from strings, use a PERCPU_ARRAY map like devised by
the sysdig guys[1] to copy more bytes:

Before:

  # trace --no-inherit -e openat touch `python -c "print "$s" 'a' * 2000"`
  touch: cannot touch 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa': File name too long
  openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", O_CREAT|O_NOCTTY|O_NONBLOCK|O_WRONLY, S_IRUGO|S_IWUGO) = -1 ENAMETOOLONG (File name too long)
  openat(AT_FDCWD, "/usr/share/locale/locale.alias", O_RDONLY|O_CLOEXEC) = 3
  openat(AT_FDCWD, "/usr/share/locale/en_US.UTF-8/LC_MESSAGES/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/usr/share/locale/en_US.utf8/LC_MESSAGES/coreutils.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
  <SNIP some openat calls>
  #

After:

  [root@quaco acme]# trace --no-inherit -e openat touch `python -c "print "$s" 'a' * 2000"`
  <STRIP what is the same as in the 'before' part>
  openat(AT_FDCWD, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", O_CREAT|O_NOCTTY|O_NONBLOC) = -1 ENAMETOOLONG (File name too long)
  <STRIP what is the same as in the 'before' part>

If we leave something like 'perf trace -e string' to trace all syscalls
with a string, and then do some 'perf top', to get some annotation for
the augmented_raw_syscalls.o BPF program we get:

       │     → callq  *ffffffffc45576d1                                                                                                          ▒
       │                augmented_args->filename.size = probe_read_str(&augmented_args->filename.value,                                          ▒
  0.05 │       mov    %eax,0x40(%r13)

Looking with pahole, expanding types, asking for hex offsets and sizes,
and use of BTF type information to see what is at that 0x40 offset from
%r13:

  # pahole -F btf -C augmented_args_filename --expand_types --hex /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
  struct augmented_args_filename {
	struct syscall_enter_args {
		long long unsigned int common_tp_fields;                                 /*     0   0x8 */
		long int           syscall_nr;                                           /*   0x8   0x8 */
		long unsigned int  args[6];                                              /*  0x10  0x30 */
	} args; /*     0  0x40 */
	/* --- cacheline 1 boundary (64 bytes) --- */
	struct augmented_filename {
		unsigned int       size;                                                 /*  0x40   0x4 */
		int                reserved;                                             /*  0x44   0x4 */
		char               value[4096];                                          /*  0x48 0x1000 */
	} filename; /*  0x40 0x1008 */

	/* size: 4168, cachelines: 66, members: 2 */
	/* last cacheline: 8 bytes */
  };
  #

Then looking if PATH_MAX leaves some signature in the tests:

       │                if (augmented_args->filename.size < sizeof(augmented_args->filename.value)) {                                            ▒
       │       cmp    $0xfff,%rdi

0xfff == 4095
sizeof(augmented_args->filename.value) == PATH_MAX == 4096

[1] https://sysdig.com/blog/the-art-of-writing-ebpf-programs-a-primer/

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <borkmann@iogearbox.net>
Cc: Gianluca Borello <g.borello@gmail.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
cc: Martin Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-76gce2d2ghzq537ubwhjkone@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-04-01 14:49:24 -03:00
Arnaldo Carvalho de Melo
c52a82f779 perf augmented_raw_syscalls: Copy strings from all syscalls with 1st or 2nd string arg
Gets the augmented_raw_syscalls a bit more useful as-is, add a comment
stating that the intent is to have all this in a map populated by
userspace via the 'syscalls' BPF map, that right now has only a flag
stating if the syscall is filtered or not.

With it:

  # grep -B1 augmented_raw ~/.perfconfig
  [trace]
	add_events = /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
  #
  # perf trace -e string
  weechat/6001 stat("/etc/localtime", 0x7ffe22c23d10)  = 0
  gnome-shell/1943 openat(AT_FDCWD, "/proc/self/stat", O_RDONLY) = 81
  weechat/6001 stat("/etc/localtime", 0x7ffe22c23d10)  = 0
  gmain/2475 inotify_add_watch(20<anon_inode:inotify>, "/home/acme/.config/firewall", 16789454) = -1 ENOENT (No such file or directory)
  gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "", 16789454) = -1 ENOENT (No such file or directory)
  gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/var/cache/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
  gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/var/lib/app-info/xmls", 16789454) = -1 ENOENT (No such file or directory)
  gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/var/lib/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
  gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/usr/share/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
  gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/usr/local/share/app-info/xmls", 16789454) = -1 ENOENT (No such file or directory)
  gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/usr/local/share/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
  gmain/2391 inotify_add_watch(3<anon_inode:inotify>, "/home/acme/.local/share/app-info/yaml", 16789454) = -1 ENOENT (No such file or directory)
  gmain/1121 inotify_add_watch(12<anon_inode:inotify>, "/etc/NetworkManager/VPN", 16789454) = -1 ENOENT (No such file or directory)
  weechat/6001 stat("/etc/localtime", 0x7ffe22c23d10)  = 0
  gmain/2050 inotify_add_watch(8<anon_inode:inotify>, "/home/acme/~", 16789454) = -1 ENOENT (No such file or directory)
  gmain/2521 inotify_add_watch(6<anon_inode:inotify>, "/var/lib/fwupd/remotes.d/lvfs-testing", 16789454) = -1 ENOENT (No such file or directory)
  weechat/6001 stat("/etc/localtime", 0x7ffe22c23d10)  = 0
  DOM Worker/22714  ... [continued]: openat())             = 257
  FS Broker 3982/3990 openat(AT_FDCWD, "/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY) = 187
  DOMCacheThread/16652 mkdir("/home/acme/.mozilla/firefox/ina67tev.default/storage/default/https+++web.whatsapp.com/cache/morgue/192", S_IRUGO|S_IXUGO|S_IWUSR) = -1 EEXIST (File exists)
  ^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-a1hxffoy8t43e0wq6bzhp23u@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-04-01 14:49:24 -03:00
Arnaldo Carvalho de Melo
76a06125dd perf augmented_syscalls: Convert to bpf_map()
To make the code more compact, end result is the same:

  # perf trace -e /home/acme/git/perf/tools/perf/examples/bpf/augmented_syscalls.c sleep 1
     0.000 ( 0.008 ms): sleep/9663 openat(dfd: CWD, filename: "/etc/ld.so.cache", flags: RDONLY|CLOEXEC) = 3
     0.022 ( 0.005 ms): sleep/9663 openat(dfd: CWD, filename: "/lib64/libc.so.6", flags: RDONLY|CLOEXEC) = 3
     0.226 ( 0.006 ms): sleep/9663 openat(dfd: CWD, filename: "/usr/lib/locale/locale-archive", flags: RDONLY|CLOEXEC) = 3
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-23z08bgizqnbc3qdsyl7jyyg@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-25 15:12:11 +01:00
Arnaldo Carvalho de Melo
f52fdd64f6 perf bpf examples: Convert etcsnoop to use bpf_map()
Making the code more compact, end result is the same:

  # trace -e /home/acme/git/perf/tools/perf/examples/bpf/etcsnoop.c
     0.000 (         ): sed/7385 openat(dfd: CWD, filename: "/etc/ld.so.cache", flags: RDONLY|CLOEXEC) ...
  2727.723 (         ): cat/7389 openat(dfd: CWD, filename: "/etc/ld.so.cache", flags: RDONLY|CLOEXEC) ...
  2728.543 (         ): cat/7389 openat(dfd: CWD, filename: "/etc/passwd")                          ...
  ^C

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-znhgz24p0daux2kay200ovc1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-25 15:12:11 +01:00
Arnaldo Carvalho de Melo
56d8175a4d perf augmented_raw_syscalls: Use bpf_map()
To make the code more compact and also paving the way to have the BTF
annotation to be done transparently.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-pjlf38sv3i1hbn5vzkr4y3ol@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-25 15:12:10 +01:00
Arnaldo Carvalho de Melo
5620196951 perf: Make perf_event_output() propagate the output() return
For the original mode of operation it isn't needed, since we report back
errors via PERF_RECORD_LOST records in the ring buffer, but for use in
bpf_perf_event_output() it is convenient to return the errors, basically
-ENOSPC.

Currently bpf_perf_event_output() returns an error indication, the last
thing it does, which is to push it to the ring buffer is that can fail
and if so, this failure won't be reported back to its users, fix it.

Reported-by: Jamal Hadi Salim <jhs@mojatatu.com>
Tested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/r/20190118150938.GN5823@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-21 17:00:57 -03:00
Arnaldo Carvalho de Melo
c48ee107bb perf augmented_raw_syscalls: Copy 'access' arg as well
This will all come from userspace, but to test the changes to make 'perf
trace' output similar to strace's, do this one more now manually.

To update the precompiled augmented_raw_syscalls.o binary I just run:

  # perf record -e ~acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.c sleep 1
  LLVM: dumping /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.022 MB perf.data ]
  #

Because to have augmented_raw_syscalls to be always used and a fast
startup and remove the need to have the llvm toolchain installed, I'm
using:

  # perf config | grep add_events
  trace.add_events=/home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
  #

So when doing changes to augmented_raw_syscals.c one needs to rebuild
the .o file.

This will be done automagically later, i.e. have a 'make' behaviour of
recompiling when the .c gets changed.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-lw3i2atyq8549fpqwmszn3qp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-12-18 16:15:18 -03:00
Arnaldo Carvalho de Melo
4623ce405d perf augmented_raw_syscalls: Do not include stdio.h
We're not using that puts() thing, and thus we don't need to define the
__bpf_stdout__ map, reducing the setup time.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-3452xgatncpil7v22minkwbo@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-12-18 12:24:00 -03:00
Arnaldo Carvalho de Melo
27f2992e7b perf augmented_syscalls: Switch to using a struct for the syscalls map values
We'll start adding more perf-syscall stuff, so lets do this prep step so
that the next ones are just about adding more fields.

Run it with the .c file once to cache the .o file:

  # trace --filter-pids 2834,2199 -e openat,augmented_raw_syscalls.c
  LLVM: dumping augmented_raw_syscalls.o
       0.000 ( 0.021 ms): tmux: server/4952 openat(dfd: CWD, filename: /proc/5691/cmdline                         ) = 11
     349.807 ( 0.040 ms): DNS Res~er #39/11082 openat(dfd: CWD, filename: /etc/hosts, flags: CLOEXEC                 ) = 44
    4988.759 ( 0.052 ms): gsd-color/2431 openat(dfd: CWD, filename: /etc/localtime                             ) = 18
    4988.976 ( 0.029 ms): gsd-color/2431 openat(dfd: CWD, filename: /etc/localtime                             ) = 18
  ^C[root@quaco bpf]#

From now on, we can use just the newly built .o file, skipping the
compilation step for a faster startup:

  # trace --filter-pids 2834,2199 -e openat,augmented_raw_syscalls.o
       0.000 ( 0.046 ms): DNS Res~er #39/11088 openat(dfd: CWD, filename: /etc/hosts, flags: CLOEXEC                 ) = 44
    1946.408 ( 0.190 ms): systemd/1 openat(dfd: CWD, filename: /proc/1071/cgroup, flags: CLOEXEC          ) = 20
    1946.792 ( 0.215 ms): systemd/1 openat(dfd: CWD, filename: /proc/954/cgroup, flags: CLOEXEC           ) = 20
  ^C#

Now on to do the same in the builtin-trace.c side of things.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-k8mwu04l8es29rje5loq9vg7@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-12-18 12:23:58 -03:00
Arnaldo Carvalho de Melo
b27b38ed94 perf trace: Implement syscall filtering in augmented_syscalls
Just another map, this time an BPF_MAP_TYPE_ARRAY, stating with
one bool per syscall, stating if it should be filtered or not.

So, with a pre-built augmented_raw_syscalls.o file, we use:

  # perf trace -e open*,augmented_raw_syscalls.o
     0.000 ( 0.016 ms): DNS Res~er #37/29652 openat(dfd: CWD, filename: /etc/hosts, flags: CLOEXEC                 ) = 138
   187.039 ( 0.048 ms): gsd-housekeepi/2436 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC                 ) = 11
   187.348 ( 0.041 ms): gsd-housekeepi/2436 openat(dfd: CWD, filename: /proc/self/mountinfo, flags: CLOEXEC       ) = 11
   188.793 ( 0.036 ms): gsd-housekeepi/2436 openat(dfd: CWD, filename: /proc/self/mountinfo, flags: CLOEXEC       ) = 11
   189.803 ( 0.029 ms): gsd-housekeepi/2436 openat(dfd: CWD, filename: /proc/self/mountinfo, flags: CLOEXEC       ) = 11
   190.774 ( 0.027 ms): gsd-housekeepi/2436 openat(dfd: CWD, filename: /proc/self/mountinfo, flags: CLOEXEC       ) = 11
   284.620 ( 0.149 ms): DataStorage/3076 openat(dfd: CWD, filename: /home/acme/.mozilla/firefox/ina67tev.default/SiteSecurityServiceState.txt, flags: CREAT|TRUNC|WRONLY, mode: IRUGO|IWUSR|IWGRP) = 167
  ^C#

What is it that this gsd-housekeeping thingy needs to open
/proc/self/mountinfo four times periodically? :-)

This map will be extended to tell per-syscall parameters, i.e. how many
bytes to copy per arg, using the function signature to get the types and
then the size of those types, via BTF.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-cy222g9ucvnym3raqvxp0hpg@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-12-18 12:23:58 -03:00
Arnaldo Carvalho de Melo
4aa792de0b Revert "perf augmented_syscalls: Drop 'write', 'poll' for testing without self pid filter"
Now that we have the "filtered_pids" logic in place, no need to do this
rough filter to avoid the feedback loop from 'perf trace's own syscalls,
revert it.

This reverts commit 7ed71f124284359676b6496ae7db724fee9da753.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-88vh02cnkam0vv5f9vp02o3h@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-11-21 12:00:31 -03:00
Arnaldo Carvalho de Melo
e312747b49 perf augmented_syscalls: Remove example hardcoded set of filtered pids
Now that 'perf trace' fills in that "filtered_pids" BPF map, remove the
set of filtered pids used as an example to test that feature.

That feature works like this:

Starting a system wide 'strace' like 'perf trace' augmented session we
noticed that lots of events take place for a pid, which ends up being
the feedback loop of perf trace's syscalls being processed by the
'gnome-terminal' process:

  # perf trace -e tools/perf/examples/bpf/augmented_raw_syscalls.c
     0.391 ( 0.002 ms): gnome-terminal/2469 read(fd: 17</dev/ptmx>, buf: 0x564b79f750bc, count: 8176) = 453
     0.394 ( 0.001 ms): gnome-terminal/2469 read(fd: 17</dev/ptmx>, buf: 0x564b79f75280, count: 7724) = -1 EAGAIN Resource temporarily unavailable
     0.438 ( 0.001 ms): gnome-terminal/2469 read(fd: 4<anon_inode:[eventfd]>, buf: 0x7fffc696aeb0, count: 16) = 8
     0.519 ( 0.001 ms): gnome-terminal/2469 read(fd: 17</dev/ptmx>, buf: 0x564b79f75280, count: 7724) = 114
     0.522 ( 0.001 ms): gnome-terminal/2469 read(fd: 17</dev/ptmx>, buf: 0x564b79f752f1, count: 7611) = -1 EAGAIN Resource temporarily unavailable
  ^C

So we can use --filter-pids to get rid of that one, and in this case what is
being used to implement that functionality is that "filtered_pids" BPF map that
the tools/perf/examples/bpf/augmented_raw_syscalls.c created and that 'perf trace'
bpf loader noticed and created a "struct bpf_map" associated that then got populated
by 'perf trace':

  # perf trace --filter-pids 2469 -e tools/perf/examples/bpf/augmented_raw_syscalls.c
     0.020 ( 0.002 ms): gnome-shell/1663 epoll_pwait(epfd: 12<anon_inode:[eventpoll]>, events: 0x7ffd8f3ef960, maxevents: 32, sigsetsize: 8) = 1
     0.025 ( 0.002 ms): gnome-shell/1663 read(fd: 24</dev/input/event4>, buf: 0x560c01bb8240, count: 8112) = 48
     0.029 ( 0.001 ms): gnome-shell/1663 read(fd: 24</dev/input/event4>, buf: 0x560c01bb8258, count: 8088) = -1 EAGAIN Resource temporarily unavailable
     0.032 ( 0.001 ms): gnome-shell/1663 read(fd: 24</dev/input/event4>, buf: 0x560c01bb8240, count: 8112) = -1 EAGAIN Resource temporarily unavailable
     0.040 ( 0.003 ms): gnome-shell/1663 recvmsg(fd: 46<socket:[35893]>, msg: 0x7ffd8f3ef950) = -1 EAGAIN Resource temporarily unavailable
    21.529 ( 0.002 ms): gnome-shell/1663 epoll_pwait(epfd: 5<anon_inode:[eventpoll]>, events: 0x7ffd8f3ef960, maxevents: 32, sigsetsize: 8) = 1
    21.533 ( 0.004 ms): gnome-shell/1663 recvmsg(fd: 82<socket:[42826]>, msg: 0x7ffd8f3ef7b0, flags: DONTWAIT|CMSG_CLOEXEC) = 236
    21.581 ( 0.006 ms): gnome-shell/1663 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_BUSY, arg: 0x7ffd8f3ef060) = 0
    21.605 ( 0.020 ms): gnome-shell/1663 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_CREATE, arg: 0x7ffd8f3eeea0) = 0
    21.626 ( 0.119 ms): gnome-shell/1663 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_SET_DOMAIN, arg: 0x7ffd8f3eee94) = 0
    21.746 ( 0.081 ms): gnome-shell/1663 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_PWRITE, arg: 0x7ffd8f3eeea0) = 0
  ^C

Oops, yet another gnome process that is involved with the output that
'perf trace' generates, lets filter that out too:

  # perf trace --filter-pids 2469,1663 -e tools/perf/examples/bpf/augmented_raw_syscalls.c
         ? (         ): wpa_supplicant/1366  ... [continued]: select()) = 0 Timeout
     0.006 ( 0.002 ms): wpa_supplicant/1366 clock_gettime(which_clock: BOOTTIME, tp: 0x7fffe5b1e430) = 0
     0.011 ( 0.001 ms): wpa_supplicant/1366 clock_gettime(which_clock: BOOTTIME, tp: 0x7fffe5b1e3e0) = 0
     0.014 ( 0.001 ms): wpa_supplicant/1366 clock_gettime(which_clock: BOOTTIME, tp: 0x7fffe5b1e430) = 0
         ? (         ): gmain/1791  ... [continued]: poll()) = 0 Timeout
     0.017 (         ): wpa_supplicant/1366 select(n: 6, inp: 0x55646fed3ad0, outp: 0x55646fed3b60, exp: 0x55646fed3bf0, tvp: 0x7fffe5b1e4a0) ...
   157.879 ( 0.019 ms): gmain/1791 inotify_add_watch(fd: 8<anon_inode:inotify>, pathname: , mask: 16789454) = -1 ENOENT No such file or directory
         ? (         ): cupsd/1001  ... [continued]: epoll_pwait()) = 0
         ? (         ): gsd-color/1908  ... [continued]: poll()) = 0 Timeout
   499.615 (         ): cupsd/1001 epoll_pwait(epfd: 4<anon_inode:[eventpoll]>, events: 0x557a21166500, maxevents: 4096, timeout: 1000, sigsetsize: 8) ...
   586.593 ( 0.004 ms): gsd-color/1908 recvmsg(fd: 3<socket:[38074]>, msg: 0x7ffdef34e800) = -1 EAGAIN Resource temporarily unavailable
         ? (         ): fwupd/2230  ... [continued]: poll()) = 0 Timeout
         ? (         ): rtkit-daemon/906  ... [continued]: poll()) = 0 Timeout
         ? (         ): rtkit-daemon/907  ... [continued]: poll()) = 1
   724.603 ( 0.007 ms): rtkit-daemon/907 read(fd: 6<anon_inode:[eventfd]>, buf: 0x7f05ff768d08, count: 8) = 8
         ? (         ): ssh/5461  ... [continued]: select()) = 1
   810.431 ( 0.002 ms): ssh/5461 clock_gettime(which_clock: BOOTTIME, tp: 0x7ffd7f39f870) = 0
   ^C

Several syscall exit events for syscalls in flight when 'perf trace' started, etc. Saner :-)

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-c3tu5yg204p5mvr9kvwew07n@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-11-21 12:00:31 -03:00
Arnaldo Carvalho de Melo
ed9a77ba77 perf augmented_syscalls: Use pid_filter
Just to test filtering a bunch of pids, now its time to go and get that
hooked up in 'perf trace', right after we load the bpf program, if we
find a "pids_filtered" map defined, we'll populate it with the filtered
pids.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-1i9s27wqqdhafk3fappow84x@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-11-21 12:00:31 -03:00
Arnaldo Carvalho de Melo
77ecb64050 perf augmented_syscalls: Drop 'write', 'poll' for testing without self pid filter
When testing system wide tracing without filtering the syscalls called
by 'perf trace' itself we get into a feedback loop, drop for now those
two syscalls, that are the ones that 'perf trace' does in its loop for
writing the syscalls it intercepts, to help with testing till we get
that filtering in place.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-rkbu536af66dbsfx51sr8yof@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-11-21 12:00:31 -03:00
Arnaldo Carvalho de Melo
66067538e0 perf augmented_syscalls: Remove needless linux/socket.h include
Leftover from when we started augmented_raw_syscalls.c from
tools/perf/examples/bpf/augmented_syscalls.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: e58a0322dbac ("perf examples bpf: Start augmenting raw_syscalls:sys_{start,exit}")
Link: https://lkml.kernel.org/n/tip-pmts9ls2skh8n3zisb4txudd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-11-21 12:00:31 -03:00
Arnaldo Carvalho de Melo
55f127b431 perf augmented_syscalls: Filter on a hard coded pid
Just to show where we'll hook pid based filters, and what we use to
obtain the current pid, using a BPF getpid() equivalent.

Now we need to remove that hardcoded PID with a BPF hash map, so that we
start by filtering 'perf trace's own PID, implement the --filter-pid
functionality, etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-oshrcgcekiyhd0whwisxfvtv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-11-21 12:00:31 -03:00
Arnaldo Carvalho de Melo
79ef68c7e1 perf augmented_syscalls: Start collecting pathnames in the BPF program
This is the start of having the raw_syscalls:sys_enter BPF handler
collecting pointer arguments, namely pathnames, and with two syscalls
that have that pointer in different arguments, "open" as it as its first
argument, "openat" as the second.

With this in place the existing beautifiers in 'perf trace' works, those
args are shown instead of just the pointer that comes with the syscalls
tracepoints.

This also serves to show and document pitfalls in the process of using
just that place in the kernel (raw_syscalls:sys_enter) plus tables
provided by userspace to collect syscall pointer arguments.

One is the need to use a barrier, as suggested by Edward, to avoid clang
optimizations that make the kernel BPF verifier to refuse loading our
pointer contents collector.

The end result should be a generic eBPF program that works in all
architectures, with the differences amongst archs resolved by the
userspace component, 'perf trace', that should get all its tables
created automatically from the kernel components where they are defined,
via string table constructors for things not expressed in BTF/DWARF
(enums, structs, etc), and otherwise using those observability files
(BTF).

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Edward Cree <ecree@solarflare.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-37dz54pmotgpnwg9tb6zuk9j@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-11-05 12:41:10 -03:00
Arnaldo Carvalho de Melo
febf8a3712 perf examples bpf: Start augmenting raw_syscalls:sys_{start,exit}
The previous approach of attaching to each syscall showed how it is
possible to augment tracepoints and use that augmentation, pointer
payloads, in the existing beautifiers in 'perf trace', but for a more
general solution we now will try to augment the main
raw_syscalls:sys_{enter,exit} syscalls, and then pass instructions in
maps so that it knows which syscalls and which pointer contents, and how
many bytes for each of the arguments should be copied.

Start with just the bare minimum to collect what is provided by those
two tracepoints via the __augmented_syscalls__ map + bpf-output perf
event, which results in perf trace showing them without connecting
enter+exit:

  # perf trace -e tools/perf/examples/bpf/augmented_raw_syscalls.c sleep 1
     0.000 sleep/11563 raw_syscalls:sys_exit:NR 59 = 0
     0.019 (         ): sleep/11563 brk() ...
     0.021 sleep/11563 raw_syscalls:sys_exit:NR 12 = 94682642325504
     0.033 (         ): sleep/11563 access(filename:, mode: R) ...
     0.037 sleep/11563 raw_syscalls:sys_exit:NR 21 = -2
     0.041 (         ): sleep/11563 openat(dfd: CWD, filename: , flags: CLOEXEC) ...
     0.044 sleep/11563 raw_syscalls:sys_exit:NR 257 = 3
     0.045 (         ): sleep/11563 fstat(fd: 3, statbuf: 0x7ffdbf7119b0) ...
     0.046 sleep/11563 raw_syscalls:sys_exit:NR 5 = 0
     0.047 (         ): sleep/11563 mmap(len: 103334, prot: READ, flags: PRIVATE, fd: 3) ...
     0.049 sleep/11563 raw_syscalls:sys_exit:NR 9 = 140196285493248
     0.050 (         ): sleep/11563 close(fd: 3) ...
     0.051 sleep/11563 raw_syscalls:sys_exit:NR 3 = 0
     0.059 (         ): sleep/11563 openat(dfd: CWD, filename: , flags: CLOEXEC) ...
     0.062 sleep/11563 raw_syscalls:sys_exit:NR 257 = 3
     0.063 (         ): sleep/11563 read(fd: 3, buf: 0x7ffdbf711b78, count: 832) ...
     0.065 sleep/11563 raw_syscalls:sys_exit:NR 0 = 832
     0.066 (         ): sleep/11563 fstat(fd: 3, statbuf: 0x7ffdbf711a10) ...
     0.067 sleep/11563 raw_syscalls:sys_exit:NR 5 = 0
     0.068 (         ): sleep/11563 mmap(len: 8192, prot: READ|WRITE, flags: PRIVATE|ANONYMOUS) ...
     0.070 sleep/11563 raw_syscalls:sys_exit:NR 9 = 140196285485056
     0.073 (         ): sleep/11563 mmap(len: 3889792, prot: EXEC|READ, flags: PRIVATE|DENYWRITE, fd: 3) ...
     0.076 sleep/11563 raw_syscalls:sys_exit:NR 9 = 140196279463936
     0.077 (         ): sleep/11563 mprotect(start: 0x7f81fd8a8000, len: 2093056) ...
     0.083 sleep/11563 raw_syscalls:sys_exit:NR 10 = 0
     0.084 (         ): sleep/11563 mmap(addr: 0x7f81fdaa7000, len: 24576, prot: READ|WRITE, flags: PRIVATE|FIXED|DENYWRITE, fd: 3, off: 1753088) ...
     0.088 sleep/11563 raw_syscalls:sys_exit:NR 9 = 140196283314176
     0.091 (         ): sleep/11563 mmap(addr: 0x7f81fdaad000, len: 14976, prot: READ|WRITE, flags: PRIVATE|FIXED|ANONYMOUS) ...
     0.093 sleep/11563 raw_syscalls:sys_exit:NR 9 = 140196283338752
     0.097 (         ): sleep/11563 close(fd: 3) ...
     0.098 sleep/11563 raw_syscalls:sys_exit:NR 3 = 0
     0.107 (         ): sleep/11563 arch_prctl(option: 4098, arg2: 140196285490432) ...
     0.108 sleep/11563 raw_syscalls:sys_exit:NR 158 = 0
     0.143 (         ): sleep/11563 mprotect(start: 0x7f81fdaa7000, len: 16384, prot: READ) ...
     0.146 sleep/11563 raw_syscalls:sys_exit:NR 10 = 0
     0.157 (         ): sleep/11563 mprotect(start: 0x561d037e7000, len: 4096, prot: READ) ...
     0.160 sleep/11563 raw_syscalls:sys_exit:NR 10 = 0
     0.163 (         ): sleep/11563 mprotect(start: 0x7f81fdcd5000, len: 4096, prot: READ) ...
     0.165 sleep/11563 raw_syscalls:sys_exit:NR 10 = 0
     0.166 (         ): sleep/11563 munmap(addr: 0x7f81fdcbb000, len: 103334) ...
     0.174 sleep/11563 raw_syscalls:sys_exit:NR 11 = 0
     0.216 (         ): sleep/11563 brk() ...
     0.217 sleep/11563 raw_syscalls:sys_exit:NR 12 = 94682642325504
     0.217 (         ): sleep/11563 brk(brk: 0x561d05453000) ...
     0.219 sleep/11563 raw_syscalls:sys_exit:NR 12 = 94682642460672
     0.220 (         ): sleep/11563 brk() ...
     0.221 sleep/11563 raw_syscalls:sys_exit:NR 12 = 94682642460672
     0.224 (         ): sleep/11563 open(filename: , flags: CLOEXEC) ...
     0.228 sleep/11563 raw_syscalls:sys_exit:NR 2 = 3
     0.229 (         ): sleep/11563 fstat(fd: 3, statbuf: 0x7f81fdaacaa0) ...
     0.230 sleep/11563 raw_syscalls:sys_exit:NR 5 = 0
     0.231 (         ): sleep/11563 mmap(len: 113045344, prot: READ, flags: PRIVATE, fd: 3) ...
     0.234 sleep/11563 raw_syscalls:sys_exit:NR 9 = 140196166418432
     0.237 (         ): sleep/11563 close(fd: 3) ...
     0.238 sleep/11563 raw_syscalls:sys_exit:NR 3 = 0
     0.262 (         ): sleep/11563 nanosleep(rqtp: 0x7ffdbf7126f0) ...
  1000.399 sleep/11563 raw_syscalls:sys_exit:NR 35 = 0
  1000.440 (         ): sleep/11563 close(fd: 1) ...
  1000.447 sleep/11563 raw_syscalls:sys_exit:NR 3 = 0
  1000.454 (         ): sleep/11563 close(fd: 2) ...
  1000.468 (         ): sleep/11563 exit_group(                                                           )
  #

In the next csets we'll connect those events to the existing enter/exit
raw_syscalls handlers in 'perf trace', just like we did with the
syscalls:sys_{enter,exit}_* tracepoints.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-5nl8l4hx1tl9pqdx65nkp6pw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-11-01 14:11:45 -03:00
Arnaldo Carvalho de Melo
7538d16397 perf augmented_syscalls: Avoid optimization to pass older BPF validators
See https://www.spinics.net/lists/netdev/msg480099.html for the whole
discussio, but to make the augmented_syscalls.c BPF program to get built
and loaded successfully in a greater range of kernels, add an extra
check.

Related patch:

  a60dd35d2e ("bpf: change bpf_perf_event_output arg5 type to ARG_CONST_SIZE_OR_ZERO")

That is in the kernel since v4.15, I couldn't figure why this is hitting
me with 4.17.17, but adding the workaround discussed there makes this
work with this fedora kernel and with 4.18.recent.

Before:

  # uname -a
  Linux seventh 4.17.17-100.fc27.x86_64 #1 SMP Mon Aug 20 15:53:11 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
  # perf trace -e tools/perf/examples/bpf/augmented_syscalls.c cat /etc/passwd > /dev/null
  libbpf: load bpf program failed: Permission denied
  libbpf: -- BEGIN DUMP LOG ---
  libbpf:
  0: (bf) r6 = r1
  1: (b7) r1 = 0
  2: (7b) *(u64 *)(r10 -8) = r1
  3: (7b) *(u64 *)(r10 -16) = r1
  4: (7b) *(u64 *)(r10 -24) = r1
  5: (7b) *(u64 *)(r10 -32) = r1
  6: (7b) *(u64 *)(r10 -40) = r1
  7: (7b) *(u64 *)(r10 -48) = r1
  8: (7b) *(u64 *)(r10 -56) = r1
  9: (7b) *(u64 *)(r10 -64) = r1
  10: (7b) *(u64 *)(r10 -72) = r1
  11: (7b) *(u64 *)(r10 -80) = r1
  12: (7b) *(u64 *)(r10 -88) = r1
  13: (7b) *(u64 *)(r10 -96) = r1
  14: (7b) *(u64 *)(r10 -104) = r1
  15: (7b) *(u64 *)(r10 -112) = r1
  16: (7b) *(u64 *)(r10 -120) = r1
  17: (7b) *(u64 *)(r10 -128) = r1
  18: (7b) *(u64 *)(r10 -136) = r1
  19: (7b) *(u64 *)(r10 -144) = r1
  20: (7b) *(u64 *)(r10 -152) = r1
  21: (7b) *(u64 *)(r10 -160) = r1
  22: (7b) *(u64 *)(r10 -168) = r1
  23: (7b) *(u64 *)(r10 -176) = r1
  24: (7b) *(u64 *)(r10 -184) = r1
  25: (7b) *(u64 *)(r10 -192) = r1
  26: (7b) *(u64 *)(r10 -200) = r1
  27: (7b) *(u64 *)(r10 -208) = r1
  28: (7b) *(u64 *)(r10 -216) = r1
  29: (7b) *(u64 *)(r10 -224) = r1
  30: (7b) *(u64 *)(r10 -232) = r1
  31: (7b) *(u64 *)(r10 -240) = r1
  32: (7b) *(u64 *)(r10 -248) = r1
  33: (7b) *(u64 *)(r10 -256) = r1
  34: (7b) *(u64 *)(r10 -264) = r1
  35: (7b) *(u64 *)(r10 -272) = r1
  36: (7b) *(u64 *)(r10 -280) = r1
  37: (7b) *(u64 *)(r10 -288) = r1
  38: (7b) *(u64 *)(r10 -296) = r1
  39: (7b) *(u64 *)(r10 -304) = r1
  40: (7b) *(u64 *)(r10 -312) = r1
  41: (bf) r7 = r10
  42: (07) r7 += -312
  43: (bf) r1 = r7
  44: (b7) r2 = 48
  45: (bf) r3 = r6
  46: (85) call bpf_probe_read#4
  47: (79) r3 = *(u64 *)(r6 +24)
  48: (bf) r1 = r10
  49: (07) r1 += -256
  50: (b7) r8 = 256
  51: (b7) r2 = 256
  52: (85) call bpf_probe_read_str#45
  53: (bf) r1 = r0
  54: (67) r1 <<= 32
  55: (77) r1 >>= 32
  56: (bf) r5 = r0
  57: (07) r5 += 56
  58: (2d) if r8 > r1 goto pc+1
   R0=inv(id=0) R1=inv(id=0,umin_value=256,umax_value=4294967295,var_off=(0x0; 0xffffffff)) R5=inv(id=0) R6=ctx(id=0,off=0,imm=0) R7=fp-312,call_-1 R8=inv256 R10=fp0,call_-1 fp-264=0
  59: (b7) r5 = 312
  60: (63) *(u32 *)(r10 -264) = r0
  61: (67) r5 <<= 32
  62: (77) r5 >>= 32
  63: (bf) r1 = r6
  64: (18) r2 = 0xffff8b9120cc8500
  66: (18) r3 = 0xffffffff
  68: (bf) r4 = r7
  69: (85) call bpf_perf_event_output#25
  70: (b7) r0 = 0
  71: (95) exit

  from 58 to 60: R0=inv(id=0) R1=inv(id=0,umax_value=255,var_off=(0x0; 0xff)) R5=inv(id=0) R6=ctx(id=0,off=0,imm=0) R7=fp-312,call_-1 R8=inv256 R10=fp0,call_-1 fp-264=0
  60: (63) *(u32 *)(r10 -264) = r0
  61: (67) r5 <<= 32
  62: (77) r5 >>= 32
  63: (bf) r1 = r6
  64: (18) r2 = 0xffff8b9120cc8500
  66: (18) r3 = 0xffffffff
  68: (bf) r4 = r7
  69: (85) call bpf_perf_event_output#25
  R5 unbounded memory access, use 'var &= const' or 'if (var < const)'

  libbpf: -- END LOG --
  libbpf: failed to load program 'syscalls:sys_enter_openat'
  libbpf: failed to load object 'tools/perf/examples/bpf/augmented_syscalls.c'
  bpf: load objects failed: err=-4007: (Kernel verifier blocks program loading)
  event syntax error: 'tools/perf/examples/bpf/augmented_syscalls.c'
                       \___ Kernel verifier blocks program loading

After:

  # perf trace -e tools/perf/examples/bpf/augmented_syscalls.c cat /etc/passwd > /dev/null
     0.000 cat/29249 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
     0.008 cat/29249 syscalls:sys_exit_openat:0x3
     0.021 cat/29249 openat(dfd: CWD, filename: /lib64/libc.so.6, flags: CLOEXEC)
     0.025 cat/29249 syscalls:sys_exit_openat:0x3
     0.180 cat/29249 open(filename: /usr/lib/locale/locale-archive, flags: CLOEXEC)
     0.185 cat/29249 syscalls:sys_exit_open:0x3
     0.242 cat/29249 openat(dfd: CWD, filename: /etc/passwd)
     0.245 cat/29249 syscalls:sys_exit_openat:0x3
  #

It also works with a more recent kernel:

  # uname -a
  Linux jouet 4.18.0-00014-g4e67b2a5df5d #6 SMP Thu Aug 30 17:34:17 -03 2018 x86_64 x86_64 x86_64 GNU/Linux
  # perf trace -e tools/perf/examples/bpf/augmented_syscalls.c cat /etc/passwd > /dev/null
     0.000 cat/26451 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
     0.020 cat/26451 syscalls:sys_exit_openat:0x3
     0.039 cat/26451 openat(dfd: CWD, filename: /lib64/libc.so.6, flags: CLOEXEC)
     0.044 cat/26451 syscalls:sys_exit_openat:0x3
     0.231 cat/26451 open(filename: /usr/lib/locale/locale-archive, flags: CLOEXEC)
     0.238 cat/26451 syscalls:sys_exit_open:0x3
     0.278 cat/26451 openat(dfd: CWD, filename: /etc/passwd)
     0.282 cat/26451 syscalls:sys_exit_openat:0x3
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Gianluca Borello <g.borello@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-wkpsivs1a9afwldbul46btbv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-09-03 15:29:53 -03:00
Arnaldo Carvalho de Melo
21d7eb9a24 perf augmented_syscalls: Check probe_read_str() return separately
Using a value returned from probe_read_str() to tell how many bytes to
copy using perf_event_output() has issues in some older kernels, like
4.17.17-100.fc27.x86_64, so separate the bounds checking done on how
many bytes to copy to a separate variable, so that the next patch has
only what is being done to make the test pass on older BPF validators.

For reference, see the discussion in this thread:

  https://www.spinics.net/lists/netdev/msg480099.html

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-jtsapwibyxrnv1xjfsgzp0fj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-09-03 15:13:33 -03:00
Arnaldo Carvalho de Melo
f5b076dc01 perf trace augmented_syscalls: Hook into syscalls:sys_exit_SYSCALL too
Hook the pair enter/exit when using augmented_{filename,sockaddr,etc}_syscall(),
this way we'll be able to see what entries are in the ELF sections generated
from augmented_syscalls.c and filter them out from the main raw_syscalls:*
tracepoints used by 'perf trace'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-cyav42qj5yylolw4attcw99z@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 15:52:21 -03:00
Arnaldo Carvalho de Melo
4c8f0a726e perf trace augmented_syscalls: Rename augmented_*_syscall__enter to just *_syscall
As we'll also hook into the syscalls:sys_exit_SYSCALL for which there
are enter hooks.

This way we'll be able to iterate the ELF file for the eBPF program,
find the syscalls that have hooks and filter them out from the general
raw_syscalls:sys_{enter,exit} tracepoint for not-yet-augmented (the ones
with pointer arguments not yet being attached to the usual syscalls
tracepoint payload) and non augmentable syscalls (syscalls without
pointer arguments).

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-cl1xyghwb1usp500354mv37h@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 15:52:21 -03:00
Arnaldo Carvalho de Melo
5e2d8a5acc perf augmented_syscalls: Update the header comments
Reflecting the fact that it now augments more than syscalls:sys_enter_SYSCALL
tracepoints that have filename strings as args. Also mention how the
extra data is handled by the by now modified 'perf trace' beautifiers,
that will use special "augmented" beautifiers when extra data is found
after the expected syscall enter/exit tracepoints.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-ybskanehmdilj5fs7080nz1g@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 15:52:20 -03:00
Arnaldo Carvalho de Melo
6ebb686225 perf trace augmented_syscalls: Augment sendto's 'addr' arg
Its a 'struct sockaddr' pointer, augment it with the same beautifier as
for 'connect' and 'bind', that all receive from userspace that pointer.

Doing it in the other direction remains to be done, hooking at the
syscalls:sys_exit_{accept4?,recvmsg} tracepoints somehow.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-k2eu68lsphnm2fthc32gq76c@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 15:52:20 -03:00
Arnaldo Carvalho de Melo
02ef288420 perf trace augmented_syscalls: Augment bind's 'myaddr' sockaddr arg
One more, to reuse the augmented_sockaddr_syscall_enter() macro
introduced from the augmentation of connect's sockaddr arg, also to get
a subset of the struct arg augmentations done using the manual method,
before switching to something automatic, using tracefs's format file or,
even better, BTF containing the syscall args structs.

  # perf trace -e tools/perf/examples/bpf/augmented_syscalls.c
     0.000 sshd/11479 bind(fd: 3<socket:[170336]>, umyaddr: { .family: NETLINK }, addrlen: 12)
     1.752 sshd/11479 bind(fd: 3<socket:[170336]>, umyaddr: { .family: INET, port: 22, addr: 0.0.0.0 }, addrlen: 16)
     1.924 sshd/11479 bind(fd: 4<socket:[170338]>, umyaddr: { .family: INET6, port: 22, addr: :: }, addrlen: 28)
  ^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-a2drqpahpmc7uwb3n3gj2plu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 15:52:20 -03:00
Arnaldo Carvalho de Melo
24a6c2cd1d perf trace augmented_syscalls: Add augmented_sockaddr_syscall_enter()
From the one for 'connect', so that we can use it with sendto and others
that receive a 'struct sockaddr'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-8bdqv1q0ndcjl1nqns5r5je2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 15:52:20 -03:00
Arnaldo Carvalho de Melo
d5a7e6613b perf trace augmented_syscalls: Augment connect's 'sockaddr' arg
As the first example of augmenting something other than a 'filename',
augment the 'struct sockaddr' argument for the 'connect' syscall:

  # perf trace -e tools/perf/examples/bpf/augmented_syscalls.c ssh -6 fedorapeople.org
     0.000 ssh/29669 connect(fd: 3, uservaddr: { .family: LOCAL, path: /var/run/nscd/socket }, addrlen: 110)
     0.042 ssh/29669 connect(fd: 3, uservaddr: { .family: LOCAL, path: /var/run/nscd/socket }, addrlen: 110)
     1.329 ssh/29669 connect(fd: 3, uservaddr: { .family: LOCAL, path: /var/run/nscd/socket }, addrlen: 110)
     1.362 ssh/29669 connect(fd: 3, uservaddr: { .family: LOCAL, path: /var/run/nscd/socket }, addrlen: 110)
     1.458 ssh/29669 connect(fd: 3, uservaddr: { .family: LOCAL, path: /var/run/nscd/socket }, addrlen: 110)
     1.478 ssh/29669 connect(fd: 3, uservaddr: { .family: LOCAL, path: /var/run/nscd/socket }, addrlen: 110)
     1.683 ssh/29669 connect(fd: 3<socket:[125942]>, uservaddr: { .family: INET, port: 53, addr: 192.168.43.1 }, addrlen: 16)
     4.710 ssh/29669 connect(fd: 3<socket:[125942]>, uservaddr: { .family: INET6, port: 22, addr: 2610:28:3090:3001:5054:ff:fea7:9474 }, addrlen: 28)
  root@fedorapeople.org: Permission denied (publickey).
  #

This is still just augmenting the syscalls:sys_enter_connect part, later
we'll wire this up to augment the enter+exit combo, like in the
tradicional 'perf trace' and 'strace' outputs.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-s7l541cbiqb22ifio6z7dpf6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 15:52:20 -03:00
Arnaldo Carvalho de Melo
9ab5aadebe perf trace: Add a etcsnoop.c augmented syscalls eBPF utility
We need to put common stuff into a separate header in tools/perf/include/bpf/
for these augmented syscalls, but I couldn't resist adding a etcsnoop.c tool,
combining augmented syscalls + filtering, that in the future will be passed
from 'perf trace''s command line, to use in building the eBPF program to do
that specific filtering at the source, inside the kernel:

  Running system wide: (hope there isn't any embarassing stuff here...  ;-) )

  # perf trace -e tools/perf/examples/bpf/etcsnoop.c
       0.000 sed/21878 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
    1741.473 cat/21883 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
    1741.892 cat/21883 openat(dfd: CWD, filename: /etc/passwd)
    1748.948 sed/21886 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
    1777.136 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1777.738 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1778.158 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1778.528 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1778.595 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1778.901 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1778.939 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1778.966 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1778.992 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.019 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.045 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.071 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.095 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.121 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.148 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.175 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.202 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.229 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.254 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.279 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.309 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.336 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.363 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.388 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.414 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.442 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.470 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.500 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.529 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.557 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.586 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.617 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.648 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.679 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.706 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.739 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.769 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.798 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.823 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.844 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.862 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.880 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.911 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.942 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1779.972 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1780.004 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
    1780.035 gvfs-udisks2-v/2302 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
   13059.154 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13060.739 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13061.990 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13063.177 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13064.265 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13065.483 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13067.383 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13068.902 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13069.922 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13070.915 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13072.612 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13074.816 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13077.343 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13078.731 NetworkManager/1237 open(filename: /etc/passwd, flags: CLOEXEC)
   13559.064 DNS Res~er #22/21054 open(filename: /etc/hosts, flags: CLOEXEC)
   22419.522 sed/21896 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   24473.313 git/21900 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   24491.988 less/21901 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   24493.793 git/21901 openat(dfd: CWD, filename: /etc/sysless)
   24565.772 sed/21924 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   25878.752 git/21928 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   26075.666 git/21928 open(filename: /etc/localtime, flags: CLOEXEC)
   26075.565 less/21929 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   26076.060 less/21929 openat(dfd: CWD, filename: /etc/sysless)
   26346.395 sed/21932 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   26483.583 sed/21938 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   26954.890 sed/21944 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   27016.165 gsd-color/1762 openat(dfd: CWD, filename: /etc/localtime)
   27016.414 gsd-color/1762 openat(dfd: CWD, filename: /etc/localtime)
   27712.313 gsd-color/2408 openat(dfd: CWD, filename: /etc/localtime)
   27712.616 gsd-color/2408 openat(dfd: CWD, filename: /etc/localtime)
   27829.035 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   27829.368 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   27829.584 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   27829.800 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   27830.107 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   27830.521 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   27961.516 git/21948 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   27987.568 less/21949 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   27988.948 bash/21949 openat(dfd: CWD, filename: /etc/sysless)
   28043.536 sed/21972 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   28736.008 sed/21978 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   34882.664 git/21991 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   34882.664 sort/21990 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   34884.441 uniq/21992 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   35593.098 git/21997 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   35638.839 git/21997 openat(dfd: CWD, filename: /etc/gitattributes)
   35702.851 sed/22000 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   36076.039 sed/22006 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   37569.049 git/22014 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   37673.712 git/22014 open(filename: /etc/localtime, flags: CLOEXEC)
   37781.710 vim/22040 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   37783.667 git/22040 openat(dfd: CWD, filename: /etc/vimrc)
   37792.394 git/22040 open(filename: /etc/nsswitch.conf, flags: CLOEXEC)
   37792.436 git/22040 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   37792.580 git/22040 open(filename: /etc/passwd, flags: CLOEXEC)
   43893.625 DNS Res~er #23/21365 open(filename: /etc/hosts, flags: CLOEXEC)
   48060.409 nm-dhcp-helper/22044 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48071.745 systemd/1 openat(dfd: CWD, filename: /etc/systemd/system/dbus-org.freedesktop.nm-dispatcher.service, flags: CLOEXEC|NOFOLLOW|NOCTTY)
   48082.780 nm-dispatcher/22049 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48111.418 systemd/22049 open(filename: /etc/NetworkManager/dispatcher.d, flags: CLOEXEC|DIRECTORY|NONBLOCK)
   48111.904 systemd/22049 open(filename: /etc/localtime, flags: CLOEXEC)
   48118.357 00-netreport/22052 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48119.668 systemd/22052 open(filename: /etc/nsswitch.conf, flags: CLOEXEC)
   48119.762 systemd/22052 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48119.887 systemd/22052 open(filename: /etc/passwd, flags: CLOEXEC)
   48120.025 systemd/22052 openat(dfd: CWD, filename: /etc/NetworkManager/dispatcher.d/00-netreport)
   48124.144 hostname/22054 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48125.492 systemd/22052 openat(dfd: CWD, filename: /etc/init.d/functions)
   48127.253 systemd/22052 openat(dfd: CWD, filename: /etc/profile.d/lang.sh)
   48127.388 systemd/22052 openat(dfd: CWD, filename: /etc/locale.conf)
   48137.749 cat/22056 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48143.519 04-iscsi/22058 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48144.438 04-iscsi/22058 open(filename: /etc/nsswitch.conf, flags: CLOEXEC)
   48144.478 04-iscsi/22058 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48144.577 04-iscsi/22058 open(filename: /etc/passwd, flags: CLOEXEC)
   48144.819 04-iscsi/22058 openat(dfd: CWD, filename: /etc/NetworkManager/dispatcher.d/04-iscsi)
   48145.620 10-ifcfg-rh-ro/22059 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48146.169 systemd/22059 open(filename: /etc/nsswitch.conf, flags: CLOEXEC)
   48146.207 systemd/22059 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48146.287 systemd/22059 open(filename: /etc/passwd, flags: CLOEXEC)
   48146.387 systemd/22059 openat(dfd: CWD, filename: /etc/NetworkManager/dispatcher.d/10-ifcfg-rh-routes.sh)
   48147.215 11-dhclient/22060 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48147.787 11-dhclient/22060 open(filename: /etc/nsswitch.conf, flags: CLOEXEC)
   48147.813 11-dhclient/22060 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48147.929 11-dhclient/22060 open(filename: /etc/passwd, flags: CLOEXEC)
   48148.016 11-dhclient/22060 openat(dfd: CWD, filename: /etc/NetworkManager/dispatcher.d/11-dhclient)
   48148.906 grep/22063 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48151.165 11-dhclient/22060 openat(dfd: CWD, filename: /etc/sysconfig/network)
   48151.560 11-dhclient/22060 open(filename: /etc/dhcp/dhclient.d/, flags: CLOEXEC|DIRECTORY|NONBLOCK)
   48151.704 11-dhclient/22060 openat(dfd: CWD, filename: /etc/dhcp/dhclient.d/chrony.sh)
   48153.593 20-chrony/22065 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48154.695 20-chrony/22065 open(filename: /etc/nsswitch.conf, flags: CLOEXEC)
   48154.756 20-chrony/22065 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48154.914 20-chrony/22065 open(filename: /etc/passwd, flags: CLOEXEC)
   48155.067 20-chrony/22065 openat(dfd: CWD, filename: /etc/NetworkManager/dispatcher.d/20-chrony)
   48156.962 25-polipo/22066 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48157.824 systemd/22066 open(filename: /etc/nsswitch.conf, flags: CLOEXEC)
   48157.866 systemd/22066 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC)
   48157.981 systemd/22066 open(filename: /etc/passwd, flags: CLOEXEC)
   48158.090 systemd/22066 openat(dfd: CWD, filename: /etc/NetworkManager/dispatcher.d/25-polipo)
   48533.616 gsd-housekeepi/2412 openat(dfd: CWD, filename: /etc/fstab, flags: CLOEXEC)
   87122.021 gsd-color/1762 openat(dfd: CWD, filename: /etc/localtime)
   87122.146 gsd-color/1762 openat(dfd: CWD, filename: /etc/localtime)
   87825.582 gsd-color/2408 openat(dfd: CWD, filename: /etc/localtime)
   87825.844 gsd-color/2408 openat(dfd: CWD, filename: /etc/localtime)
   87829.524 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   87830.531 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   87831.288 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   87832.011 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   87832.672 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   87833.276 gnome-shell/2125 openat(dfd: CWD, filename: /etc/localtime)
   ^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-0o770jvdcy04ee6vhv6v471m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 15:52:19 -03:00
Arnaldo Carvalho de Melo
16cc63593f perf trace: Augment 'newstat' (aka 'stat') filename ptr
This one will need some more work, that 'statbuf' pointer requires a
beautifier in 'perf trace'.

  # perf trace -e tools/perf/examples/bpf/augmented_syscalls.c
     0.000 weechat/3596 stat(filename: /etc/localtime, statbuf: 0x7ffd87d11f60)
     0.186 perf/29818 openat(dfd: CWD, filename: /sys/kernel/debug/tracing/events/syscalls/sys_enter_stat/format)
     0.279 perf/29818 openat(dfd: CWD, filename: /sys/kernel/debug/tracing/events/syscalls/sys_enter_newstat/for)
     0.670 perf/29818 openat(dfd: CWD, filename: /sys/kernel/debug/tracing/events/syscalls/sys_enter_openat/form)
    60.805 DNS Res~er #20/21308 stat(filename: /etc/resolv.conf, statbuf: 0x7ffa733fe4a0)
    60.836 DNS Res~er #20/21308 open(filename: /etc/hosts, flags: CLOEXEC)
    60.931 perf/29818 openat(dfd: CWD, filename: /sys/kernel/debug/tracing/events/syscalls/sys_enter_open/format)
   607.070 DNS Res~er #21/29812 stat(filename: /etc/resolv.conf, statbuf: 0x7ffa5e1fe3f0)
   607.098 DNS Res~er #21/29812 open(filename: /etc/hosts, flags: CLOEXEC)
   999.336 weechat/3596 stat(filename: /etc/localtime, statbuf: 0x7ffd87d11f60)
^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-4lhabe7m4uzo76lnqpyfmnvk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 15:52:19 -03:00