The patch adds a new option to limit the output file size, then based on
it, we can create a wrapper of the perf command that uses the option to
avoid exhausting the disk space by the unconscious user.

In order to make the perf.data parsable, we just limit the sample data
size, since the perf.data consists of many headers and sample data and
other data, the actual size of the recorded file will bigger than the
setting value.

Testing it:

  # ./perf record -a -g --max-size=10M
  Couldn't synthesize bpf events.
  [ perf record: perf size limit reached (10249 KB), stopping session ]
  [ perf record: Woken up 32 times to write data ]
  [ perf record: Captured and wrote 10.133 MB perf.data (71964 samples) ]

  # ls -lh perf.data
  -rw------- 1 root root 11M Oct 22 14:32 perf.data

  # ./perf record -a -g --max-size=10K
  [ perf record: perf size limit reached (10 KB), stopping session ]
  Couldn't synthesize bpf events.
  [ perf record: Woken up 0 times to write data ]
  [ perf record: Captured and wrote 1.546 MB perf.data (69 samples) ]

  # ls -l perf.data
  -rw------- 1 root root 1626952 Oct 22 14:36 perf.data

Committer notes:

Fixed the build in multiple distros by using PRIu64 to print u64 struct
members, fixing this:

  builtin-record.c: In function 'record__write':
  builtin-record.c:150:5: error: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'u64' [-Werror=format=]
       rec->bytes_written >> 10);
       ^
    CC       /tmp/build/pe
Signed-off-by: Jiwei Sun <jiwei.sun@windriver.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Danter <richard.danter@windriver.com>
Link: http://lore.kernel.org/lkml/20191022080901.3841-1-jiwei.sun@windriver.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>