linux-toradex.git/tools/perf/builtin-trace.c, branch v5.10-rc6

perf trace: Fix segfault when trying to trace events by cgroup

2020-11-03T11:31:03+00:00

  # ./perf trace -e sched:sched_switch -G test -a sleep 1
  perf: Segmentation fault
  Obtained 11 stack frames.
  ./perf(sighandler_dump_stack+0x43) [0x55cfdc636db3]
  /lib/x86_64-linux-gnu/libc.so.6(+0x3efcf) [0x7fd23eecafcf]
  ./perf(parse_cgroups+0x36) [0x55cfdc673f36]
  ./perf(+0x3186ed) [0x55cfdc70d6ed]
  ./perf(parse_options_subcommand+0x629) [0x55cfdc70e999]
  ./perf(cmd_trace+0x9c2) [0x55cfdc5ad6d2]
  ./perf(+0x1e8ae0) [0x55cfdc5ddae0]
  ./perf(+0x1e8ded) [0x55cfdc5ddded]
  ./perf(main+0x370) [0x55cfdc556f00]
  /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe6) [0x7fd23eeadb96]
  ./perf(_start+0x29) [0x55cfdc557389]
  Segmentation fault
  #

 It happens because "struct trace" in option->value is passed to the
 parse_cgroups function instead of "struct evlist".

Fixes: 9ea42ba4411ac ("perf trace: Support setting cgroups as targets")
Signed-off-by: Stanislav Ivanichkin 
Tested-by: Arnaldo Carvalho de Melo 
Acked-by: Namhyung Kim 
Cc: Dmitry Monakhov 
Link: http://lore.kernel.org/lkml/20201027094357.94881-1-sivanichkin@yandex-team.ru
Signed-off-by: Arnaldo Carvalho de Melo

perf trace: Fix off by ones in memset() after realloc() in arches using libaudit

2020-10-13T16:57:41+00:00

'perf trace ls' started crashing after commit d21cb73a9025 on
!HAVE_SYSCALL_TABLE_SUPPORT configs (armv7l here) like this:

  0  strlen () at ../sysdeps/arm/armv6t2/strlen.S:126
  1  0xb6800780 in __vfprintf_internal (s=0xbeff9908, s@entry=0xbeff9900, format=0xa27160 "]: %s()", ap=..., mode_flags=) at vfprintf-internal.c:1688
  ...
  5  0x0056ecdc in fprintf (__fmt=0xa27160 "]: %s()", __stream=) at /usr/include/bits/stdio2.h:100
  6  trace__sys_exit (trace=trace@entry=0xbeffc710, evsel=evsel@entry=0xd968d0, event=, sample=sample@entry=0xbeffc3e8) at builtin-trace.c:2475
  7  0x00566d40 in trace__handle_event (sample=0xbeffc3e8, event=, trace=0xbeffc710) at builtin-trace.c:3122
  ...
  15 main (argc=2, argv=0xbefff6e8) at perf.c:538

It is because memset in trace__read_syscall_info zeroes wrong memory:

1) when initializing for the first time, it does not reset the last id.

2) in other cases, it resets the last id of previous buffer.

ad 1) it causes the crash above as sc->name used in the fprintf above
      contains garbage.

ad 2) it sets nonexistent from true back to false for id 11 here. Not
      sure, what the consequences are.

So fix it by introducing a special case for the initial initialization
and do the right +1 in both cases.

Fixes: d21cb73a9025 ("perf trace: Grow the syscall table as needed when using libaudit")
Signed-off-by: Jiri Slaby 
Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20201001093419.15761-1-jslaby@suse.cz
Signed-off-by: Arnaldo Carvalho de Melo

perf record: Extend -D,--delay option with -1 value

2020-08-04T11:50:04+00:00

Extend -D,--delay option with -1 to start collection with events
disabled to be enabled later by 'enable' command provided via control
file descriptor.

Signed-off-by: Alexey Budankov 
Acked-by: Jiri Olsa 
Acked-by: Namhyung Kim 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/3e7d362c-7973-ee5d-e81e-c60ea22432c3@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Fix the class prefix for 'struct evlist' strerror methods

2020-06-22T19:28:09+00:00

To differentiate from libperf's 'struct perf_evlist' methods.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Fix the class prefix for 'struct evlist' 'add' evsel methods

2020-06-22T19:28:09+00:00

To differentiate from libperf's 'struct perf_evlist' methods.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Signed-off-by: Arnaldo Carvalho de Melo

perf trace: Grow the syscall table as needed when using libaudit

2020-05-29T19:51:11+00:00

The audit-libs API doesn't provide a way to figure out what is the
syscall with the greatest number/id, take that into account when using
that method to go on growing the syscall table as we the syscalls go on
appearing on the radar.

With this the libaudit based method is back working, i.e. when building
with:

  $ make NO_SYSCALL_TABLE=1 O=/tmp/build/perf -C tools/perf install-bin
  
  Auto-detecting system features:
  
  ...                      libaudit: [ on  ]
  ...                        libbfd: [ on  ]
  ...                        libcap: [ on  ]
  
  $ ldd ~/bin/perf | grep audit
	libaudit.so.1 => /lib64/libaudit.so.1 (0x00007faef22df000)
  $

perf trace is back working, which makes it functional in arches other
than x86_64, powerpc, arm64 and s390, that provides these generators:

  $ find tools/perf/arch/ -name "*syscalltbl*"
  tools/perf/arch/x86/entry/syscalls/syscalltbl.sh
  tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
  tools/perf/arch/s390/entry/syscalls/mksyscalltbl
  tools/perf/arch/powerpc/entry/syscalls/mksyscalltbl
  $

Example output forcing the libaudit method on x86_64:

  # perf trace -e file,nanosleep sleep 0.001
           ? (         ): sleep/859090  ... [continued]: execve())                                   = 0
       0.045 ( 0.005 ms): sleep/859090 access(filename: 0x8733e850, mode: R)                         = -1 ENOENT (No such file or directory)
       0.055 ( 0.005 ms): sleep/859090 openat(dfd: CWD, filename: 0x8733ba29, flags: RDONLY|CLOEXEC) = 3
       0.079 ( 0.005 ms): sleep/859090 openat(dfd: CWD, filename: 0x87345d20, flags: RDONLY|CLOEXEC) = 3
       0.085 ( 0.002 ms): sleep/859090 read(fd: 3, buf: 0x7ffd9d483f58, count: 832)                  = 832
       0.090 ( 0.002 ms): sleep/859090 read(fd: 3, buf: 0x7ffd9d483b50, count: 784)                  = 784
       0.094 ( 0.002 ms): sleep/859090 read(fd: 3, buf: 0x7ffd9d483b20, count: 32)                   = 32
       0.098 ( 0.002 ms): sleep/859090 read(fd: 3, buf: 0x7ffd9d483ad0, count: 68)                   = 68
       0.109 ( 0.002 ms): sleep/859090 read(fd: 3, buf: 0x7ffd9d483a50, count: 784)                  = 784
       0.113 ( 0.002 ms): sleep/859090 read(fd: 3, buf: 0x7ffd9d483730, count: 32)                   = 32
       0.117 ( 0.002 ms): sleep/859090 read(fd: 3, buf: 0x7ffd9d483710, count: 68)                   = 68
       0.320 ( 0.008 ms): sleep/859090 openat(dfd: CWD, filename: 0x872c3660, flags: RDONLY|CLOEXEC) = 3
       0.372 ( 1.057 ms): sleep/859090 nanosleep(rqtp: 0x7ffd9d484ac0)                               = 0
  #

There are still some limitations when using the libaudit method, that
will be fixed at some point, i.e., this works with the mksyscalltbl
method but not with libaudit's:

  # perf trace -e file,*sleep sleep 0.001
  event syntax error: '*sleep'
                       \___ parser error
  Run 'perf list' for a list of valid events

   Usage: perf trace [] []
      or: perf trace [] --  []
      or: perf trace record [] []
      or: perf trace record [] --  []

      -e, --event    event/syscall selector. use 'perf list' to list available events
  #

Cc: Adrian Hunter 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Signed-off-by: Arnaldo Carvalho de Melo

perf trace: Fix compilation error for make NO_LIBBPF=1 DEBUG=1

2020-05-28T13:03:26+00:00

The perf compilation fails for NO_LIBBPF=1 DEBUG=1 with:

  $ make NO_LIBBPF=1 DEBUG=1
    BUILD:   Doing 'make -j8' parallel build
    CC       builtin-trace.o
    LD       perf-in.o
    LINK     perf
  /usr/bin/ld: perf-in.o: in function `trace__find_bpf_map_by_name':
  /home/jolsa/kernel/linux-perf/tools/perf/builtin-trace.c:4608: undefined reference to `bpf_object__find_map_by_name'
  collect2: error: ld returned 1 exit status
  make[2]: *** [Makefile.perf:631: perf] Error 1
  make[1]: *** [Makefile.perf:225: sub-make] Error 2
  make: *** [Makefile:70: all] Error 2

Move trace__find_bpf_map_by_name calls under HAVE_LIBBPF_SUPPORT ifdef
and add make test for this.

Committer notes:

Add missing:

  run += make_no_libbpf_DEBUG

Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20200518141027.3765877-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Rename perf_evselnew() to evselnew()

2020-05-28T13:03:24+00:00

As these are 'struct evsel' methods, not part of tools/lib/perf/, aka
libperf, to whom the perf_ prefix belongs.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Signed-off-by: Arnaldo Carvalho de Melo

perf trace: Rename perf_evsel() operating on 'struct evsel ' to evsel*()

2020-05-05T19:35:31+00:00

As those is a 'struct evsel' methods, not part of tools/lib/perf/, aka
libperf, to whom the perf_ prefix belongs.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Rename perf_evselenv() to evselenv()