The 'perf trace' tool is suppressing args set to zero, with the
exception of string tables (strarrays), which are kinda like enums, i.e.
we have maps to go from numbers to strings.

But the 'cmd' fcntl arg requires more specialized treatment, as its
value will regulate if the next fcntl syscall arg, 'arg', should be
ignored (not used) and also how to format the syscall return (fd, file
flags, etc), so add a 'show_zero" bool to struct syscall_arg_fmt, to
regulate this more explicitely.

Will be used in a following patch with fcntl, here is just the
mechanism.

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: http://lkml.kernel.org/n/tip-all738jctxets8ffyizp5lzo@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Instead of having syscall_fmt.{arg_scnprintf,arg_parm}, introduce
struct syscall_arg_fmt and have these two, paving the way for more
state to change the formatting algorithms.

For instance, in the 'fcntl' 'cmd' case it is better not to suppress
it when being zero, showing instead its name "DUPFD".

We had that in an ad-hoc way just for strarrays, but with more involved
cases like fcntl, that can't be done with just a strarray, we'll need
a ".show_zero" arg in the 'cmd' syscall_arg_fmt.

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: http://lkml.kernel.org/n/tip-ch06o2j72zbjx5xww4qp67au@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Like will be done with fcntl(fd, F_GETLEASE, F_RDLCK|F_WRLCK|F_UNLCK)

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: http://lkml.kernel.org/n/tip-3p11bgirtntjfmbixfkz8i2m@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now that the beautifiers are being split into multiple source and object
files, we will need more of them exported, do it for the 'fd' one, will
be used to augment the return of some syscalls that may return an 'fd',
such as fcntl(fd, F_DUPFD).

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: http://lkml.kernel.org/n/tip-39sosu12hhywyunqf5s74ewf@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We need the current thread and the trace internal state so that we can
use the fd beautifier to augment syscall returns, so use struct
syscall_arg with some fields that make sense on returns (val, thread,
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: http://lkml.kernel.org/n/tip-lqag8e86ybidrh5zpqne05ov@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Things like fcntl will use this to set the right formatter based on its
'cmd' argument.

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: http://lkml.kernel.org/n/tip-4ea3wplb8b4j7aymj0d5uo0h@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Those introduced by the commit c75b1d94 ("fs: add fcntl() interface for
setting/getting write life time hints"), tested using the proggie in that
commit comment:

  # perf trace -e fcntl ./write_hint write_hint.c
  fcntl: F_GET_RW_HINT: Invalid argument
     0.000 ( 0.006 ms): write_hint/7576 fcntl(fd: 3, cmd: GET_RW_HINT, arg: 0x7ffc6c918da0) = -1 EINVAL Invalid argument
     0.014 ( 0.004 ms): write_hint/7576 fcntl(fd: 4, cmd: GETFL) = 33794
  # perf trace -e fcntl ./write_hint write_hint.c 1
  fcntl: F_SET_RW_HINT: Invalid argument
     0.000 ( 0.007 ms): write_hint/7578 fcntl(fd: 3, cmd: SET_RW_HINT, arg: 0x7fff03866d70) = -1 EINVAL Invalid argument
     0.019 ( 0.002 ms): write_hint/7578 fcntl(fd: 4, cmd: GETFL) = 33794
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-iacglkc99cchou87k62736dn@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Sometimes it should be printed as an hex number, like with F_SETLK,
F_SETLKW and F_GETLK, that treat 'arg' as a struct flock pointer, in
other cases it is just an integer.

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: http://lkml.kernel.org/n/tip-2gykg6enk7vos6q0m97hkgsg@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Will be used in the fcntl arg beautifier, that nowadays formats as '%ld'
because there is no explicit arg beautifier attached, but as we will
have to first decide what beautifier to use (i.e. it may be a pointer,
etc) then we need to have this exported as a separate beautifier to be
called from there.

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: http://lkml.kernel.org/n/tip-d7bfs3m8m70j3zckeam0kk5d@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The most basic ones, for pointers, unaugmented fds, etc, to be used
in the initial fcntl 'arg' beautifier.

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: http://lkml.kernel.org/n/tip-g0lugj4vv6p4jtge32hid6q6@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

For instance, fcntl's upcoming 'arg' formatter needs to look at the
'cmd' value to decide how to format its value, sometimes it is a file
flags, sometimes an fd, a pointer to a structure, 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: http://lkml.kernel.org/n/tip-2tw2jfaqm48dtw8a4addghze@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

A series of fcntl cmds ignore the third argument, so mask it.

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: http://lkml.kernel.org/n/tip-6vtl3zq1tauamrhm8o380ptn@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

As we'll call it from the fcntl cmd scnprintf method, that needs to look
at the cmd to mask the next fcntl argument when it is ignored.

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: http://lkml.kernel.org/n/tip-fzlvkhew5vbxefneuciihgbc@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We were only beautifying (transforming from an integer to its name) the
non-linux specific fcntl syscall cmd args, fix it:

Before:

  # perf trace -e fcntl -p 2472
     0.000 ( 0.017 ms): gnome-terminal/2472 fcntl(fd: 55, cmd: 1030) = 56
  ^C#

After:

  # trace -e fcntl -p 2472
     0.000 ( 0.015 ms): gnome-terminal/2472 fcntl(fd: 55, cmd: DUPFD_CLOEXEC) = 56
  ^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: http://lkml.kernel.org/n/tip-zigsxruk4wbfn8iylboy9wzo@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The initial ones already had that "F_" prefix stripped to make things
shorter, some hadn't, do it now.

We do this to make the 'perf trace' output more compact. At some point
perhaps the best thing to do is to have the tool do this stripping
automatically, letting the user also decide if this is to be done or
not. For now, be consistent.

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: http://lkml.kernel.org/n/tip-2iot106xkl8rgb0hb8zm3gq5@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The s390 architecture maps sys_mmap (nr 90) into sys_old_mmap.  For this
reason perf trace can't find the proper syscall event to get args format
from and displays it wrongly as 'continued'.

To fix that fill the "alias" field with "old_mmap" for trace's mmap record
to get the correct translation.

Before:
     0.042 ( 0.011 ms): vest/43052 fstat(statbuf: 0x3ffff89fd90                ) = 0
     0.042 ( 0.028 ms): vest/43052  ... [continued]: mmap()) = 0x3fffd6e2000
     0.072 ( 0.025 ms): vest/43052 read(buf: 0x3fffd6e2000, count: 4096        ) = 6

After:
     0.045 ( 0.011 ms): fstat(statbuf: 0x3ffff8a0930                           ) = 0
     0.057 ( 0.018 ms): mmap(arg: 0x3ffff8a0858                                ) = 0x3fffd14a000
     0.076 ( 0.025 ms): read(buf: 0x3fffd14a000, count: 4096                   ) = 6
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170531113557.19175-1-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

More needs to be done to have the actual functions and variables in a
smaller .c file that can then be included in the python binding,
avoiding dragging more stuff into it.

Link: http://lkml.kernel.org/n/tip-uecxz7cqkssouj7tlxrkqpl4@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Not needed in this header, added to the places that need poll(), wait()
and a few other prototypes.

Link: http://lkml.kernel.org/n/tip-i39c7b6xmo1vwd9wxp6fmkl0@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

And remove it from util.h, disentangling it a bit more.

Link: http://lkml.kernel.org/n/tip-2zg9s5nx90yde64j3g4z2uhk@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Disentangling util.h header mess a bit more.

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: http://lkml.kernel.org/n/tip-aj6je8ly377i4upedmjzdsq6@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Removing it from util.h, part of an effort to disentangle the includes
hell, that makes changes to util.h or something included by it to cause
a complete rebuild of the tools.

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: http://lkml.kernel.org/n/tip-ztrjy52q1rqcchuy3rubfgt2@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Moving them from util.h, where they don't belong. Since libc already
have string.h, name it slightly differently, as string2.h.

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: http://lkml.kernel.org/n/tip-eh3vz5sqxsrdd8lodoro4jrw@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Continuing the split of util.[ch] into more manageable bits.

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: http://lkml.kernel.org/n/tip-5eu367rwcwnvvn7fz09l7xpb@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

More stuff that came from git, out of the hodge-podge that is util.h

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: http://lkml.kernel.org/n/tip-e3lana4gctz3ub4hn4y29hkw@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Needed to use the PRI[xu](32,64) formatting macros.

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: http://lkml.kernel.org/n/tip-wkbho8kaw24q67dd11q0j39f@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To pave the way for further cleanups where linux/kernel.h may stop being
included in some header.

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: http://lkml.kernel.org/n/tip-qqxan6tfsl6qx3l0v3nwgjvk@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To test it, build samples/statx/test_statx, which I did as:

  $ make headers_install
  $ cc -I ~/git/linux/usr/include samples/statx/test-statx.c -o /tmp/statx

And then use perf trace on it:

  # perf trace -e statx /tmp/statx /etc/passwd
  statx(/etc/passwd) = 0
  results=7ff
    Size: 3496            Blocks: 8          IO Block: 4096    regular file
  Device: fd:00           Inode: 280156      Links: 1
  Access: (0644/-rw-r--r--)  Uid:     0   Gid:     0
  Access: 2017-03-29 16:01:01.650073438-0300
  Modify: 2017-03-10 16:25:14.156479354-0300
  Change: 2017-03-10 16:25:14.171479328-0300
     0.000 ( 0.007 ms): statx/30648 statx(dfd: CWD, filename: 0x7ef503f4, flags: SYMLINK_NOFOLLOW, mask: TYPE|MODE|NLINK|UID|GID|ATIME|MTIME|CTIME|INO|SIZE|BLOCKS|BTIME, buffer: 0x7fff7ef4eb10) = 0
  #

Using the test-stat.c options to change the mask:

  # perf trace -e statx /tmp/statx -O /etc/passwd > /dev/null
     0.000 ( 0.008 ms): statx/30745 statx(dfd: CWD, filename: 0x3a0753f4, flags: SYMLINK_NOFOLLOW, mask: BTIME, buffer: 0x7ffd3a0735c0) = 0
  #
  # perf trace -e statx /tmp/statx -A /etc/passwd > /dev/null
     0.000 ( 0.010 ms): statx/30757 statx(dfd: CWD, filename: 0xa94e63f4, flags: SYMLINK_NOFOLLOW|NO_AUTOMOUNT, mask: TYPE|MODE|NLINK|UID|GID|ATIME|MTIME|CTIME|INO|SIZE|BLOCKS|BTIME, buffer: 0x7ffea94e49d0) = 0
  #
  # trace --no-inherit -e statx /tmp/statx -F /etc/passwd > /dev/null
     0.000 ( 0.011 ms): statx(dfd: CWD, filename: 0x3b02d3f3, flags: SYMLINK_NOFOLLOW|STATX_FORCE_SYNC, mask: TYPE|MODE|NLINK|UID|GID|ATIME|MTIME|CTIME|INO|SIZE|BLOCKS|BTIME, buffer: 0x7ffd3b02c850) = 0
  #
  # trace --no-inherit -e statx /tmp/statx -F -L /etc/passwd > /dev/null
     0.000 ( 0.008 ms): statx(dfd: CWD, filename: 0x15cff3f3, flags: STATX_FORCE_SYNC, mask: TYPE|MODE|NLINK|UID|GID|ATIME|MTIME|CTIME|INO|SIZE|BLOCKS|BTIME, buffer: 0x7fff15cfdda0) = 0
  #
  # trace --no-inherit -e statx /tmp/statx -D -O /etc/passwd > /dev/null
     0.000 ( 0.009 ms): statx(dfd: CWD, filename: 0xfa37f3f3, flags: SYMLINK_NOFOLLOW|STATX_DONT_SYNC, mask: BTIME, buffer: 0x7ffffa37da20) = 0
  #

Adding a probe to get the filename collected as well:

  # perf probe 'vfs_getname=getname_flags:72 pathname=result->name:string'
  Added new event:
    probe:vfs_getname    (on getname_flags:72 with pathname=result->name:string)

  You can now use it in all perf tools, such as:

	  perf record -e probe:vfs_getname -aR sleep 1

  # trace --no-inherit -e statx /tmp/statx -D -O /etc/passwd > /dev/null
     0.169 ( 0.007 ms): statx(dfd: CWD, filename: /etc/passwd, flags: SYMLINK_NOFOLLOW|STATX_DONT_SYNC, mask: BTIME, buffer: 0x7ffda9bf50f0) = 0
  #

Same technique could be used to collect and beautify the result put in
the 'buffer' argument.

Finally do a system wide 'perf trace' session looking for any use of statx,
then run the test proggie with various flags:

  # trace -e statx
   16612.967 ( 0.028 ms): statx/4562 statx(dfd: CWD, filename: /tmp/statx, flags: SYMLINK_NOFOLLOW, mask: TYPE|MODE|NLINK|UID|GID|ATIME|MTIME|CTIME|INO|SIZE|BLOCKS|BTIME, buffer: 0x7ffef195d660) = 0
   33064.447 ( 0.011 ms): statx/4569 statx(dfd: CWD, filename: /tmp/statx, flags: SYMLINK_NOFOLLOW|STATX_FORCE_SYNC, mask: TYPE|MODE|NLINK|UID|GID|ATIME|MTIME|CTIME|INO|SIZE|BLOCKS|BTIME, buffer: 0x7ffc5484c790) = 0
   36050.891 ( 0.023 ms): statx/4576 statx(dfd: CWD, filename: /tmp/statx, flags: SYMLINK_NOFOLLOW, mask: BTIME, buffer: 0x7ffeb18b66e0) = 0
   38039.889 ( 0.023 ms): statx/4584 statx(dfd: CWD, filename: /tmp/statx, flags: SYMLINK_NOFOLLOW, mask: TYPE|MODE|NLINK|UID|GID|ATIME|MTIME|CTIME|INO|SIZE|BLOCKS|BTIME, buffer: 0x7fff1db0ea90) = 0
  ^C#

This one also starts moving the beautifiers from files directly included
in builtin-trace.c to separate objects + a beauty.h header with
prototypes, so that we can add test cases in tools/perf/tests/ to fire
syscalls with various arguments and then get them intercepted as
syscalls:sys_enter_foo or raw_syscalls:sys_enter + sys_exit to then
format and check that the formatted output is the one we expect.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Ahern <dsahern@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-xvzw8eynffvez5czyzidhrno@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Which may happen when we start a tracing session and a thread is waiting
for something like "poll" to return, in which case we better print "?"
both for the syscall entry timestamp and for the duration.

E.g.:

Tracing existing mutt session:

  # perf trace -p `pidof mutt`
          ? (     ?   ): mutt/17135  ... [continued]: poll()) = 1
      0.027 ( 0.013 ms): mutt/17135 read(buf: 0x7ffcb3c42cef, count: 1) = 1
      0.047 ( 0.008 ms): mutt/17135 poll(ufds: 0x7ffcb3c42c50, nfds: 1, timeout_msecs: 1000) = 1
      0.059 ( 0.008 ms): mutt/17135 read(buf: 0x7ffcb3c42cef, count: 1) = 1
  <SNIP>

Before it would print a large number because we'd do:

  ttrace->entry_time - trace->base_time

And entry_time would be 0, while base_time would be the timestamp for
the first event 'perf trace' reads, oops.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Claudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-wbcb93ofva2qdjd5ltn5eeqq@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We got it from the git sources but never used it for anything, with the
place where this would be somehow used remaining:

  static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
  {
	prefix = NULL;
	if (p->option & RUN_SETUP)
		prefix = NULL; /* setup_perf_directory(); */

Ditch it.

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: http://lkml.kernel.org/n/tip-uw5swz05vol0qpr32c5lpvus@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In trace__vfs_getname() and when checking if a thread is filtered in
trace__process_sample() we were not dropping the reference obtained via
machine__findnew_thread(), fix it.

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: http://lkml.kernel.org/n/tip-9gc470phavxwxv5d9w7ck8ev@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Trivial fix removing a tab in an error path.

Link: http://lkml.kernel.org/n/tip-c14mk6cqaiby8gf5rpft3d9r@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It shouldn't be zero, but if the 'perf probe' on getname_flags() (or
elsewhere in the future we need to probe to catch the pathname for
syscalls like 'open' being copied from userspace to the kernel) is
misplaced somehow, then we will end up not allocating space and trying
to copy the "" empty string to ttrace->filename.name, causing a
segfault, fix it.

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: http://lkml.kernel.org/n/tip-c4f1t6sx1nczuzop19r5si5s@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Introduce a new option to record PERF_RECORD_NAMESPACES events emitted
by the kernel when fork, clone, setns or unshare are invoked. And update
perf-record documentation with the new option to record namespace
events.

Committer notes:

Combined it with a later patch to allow printing it via 'perf report -D'
and be able to test the feature introduced in this patch. Had to move
here also perf_ns__name(), that was introduced in another later patch.

Also used PRIu64 and PRIx64 to fix the build in some enfironments wrt:

  util/event.c:1129:39: error: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type 'long long unsigned int' [-Werror=format=]
     ret  += fprintf(fp, "%u/%s: %lu/0x%lx%s", idx
                                         ^
Testing it:

  # perf record --namespaces -a
  ^C[ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 1.083 MB perf.data (423 samples) ]
  #
  # perf report -D
  <SNIP>
  3 2028902078892 0x115140 [0xa0]: PERF_RECORD_NAMESPACES 14783/14783 - nr_namespaces: 7
                [0/net: 3/0xf0000081, 1/uts: 3/0xeffffffe, 2/ipc: 3/0xefffffff, 3/pid: 3/0xeffffffc,
                 4/user: 3/0xeffffffd, 5/mnt: 3/0xf0000000, 6/cgroup: 3/0xeffffffb]

  0x1151e0 [0x30]: event: 9
  .
  . ... raw event: size 48 bytes
  .  0000:  09 00 00 00 02 00 30 00 c4 71 82 68 0c 7f 00 00  ......0..q.h....
  .  0010:  a9 39 00 00 a9 39 00 00 94 28 fe 63 d8 01 00 00  .9...9...(.c....
  .  0020:  03 00 00 00 00 00 00 00 ce c4 02 00 00 00 00 00  ................
  <SNIP>
        NAMESPACES events:          1
  <SNIP>
  #
Signed-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/148891930386.25309.18412039920746995488.stgit@hbathini.in.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It now can have negative value to suppress the message entirely.  So it
needs to check it being positive.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170217081742.17417-3-namhyung@kernel.org
[ Adjust fuzz on tools/perf/util/pmu.c, add > 0 checks in many other places ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Makes it easier to specify both events and syscalls (to be formatter
strace-like), i.e. previously one would have to do:

  # perf trace -e nanosleep --event sched:sched_switch usleep 1

Now it is possible to do:

  # perf trace -e nanosleep,sched:sched_switch usleep 1
     0.000 ( 0.021 ms): usleep/17962 nanosleep(rqtp: 0x7ffdedd61ec0) ...
     0.021 (         ): sched:sched_switch:usleep:17962 [120] S ==> swapper/1:0 [120])
     0.000 ( 0.066 ms): usleep/17962  ... [continued]: nanosleep()) = 0
  #

The old style --expr and using both -e and --event continues to work.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-ieg6bakub4657l9e6afn85r4@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Leverage pid/tid filtering done by symbol_conf hooks.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/1480091392-35645-1-git-send-email-dsa@cumulusnetworks.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Instead of the one when another syscall takes place while another is being
processed (in another CPU, but we show it serialized, so need to "interrupt"
the other), and also when finally showing the sys_enter + sys_exit + duration,
where we were showing the sample->time for the sys_exit, duh.

Before:

  # perf trace sleep 1
  <SNIP>
     0.373 (   0.001 ms): close(fd: 3                   ) = 0
  1000.626 (1000.211 ms): nanosleep(rqtp: 0x7ffd6ddddfb0) = 0
  1000.653 (   0.003 ms): close(fd: 1                   ) = 0
  1000.657 (   0.002 ms): close(fd: 2                   ) = 0
  1000.667 (   0.000 ms): exit_group(                   )
  #

After:

  # perf trace sleep 1
  <SNIP>
     0.336 (   0.001 ms): close(fd: 3                   ) = 0
     0.373 (1000.086 ms): nanosleep(rqtp: 0x7ffe303e9550) = 0
  1000.481 (   0.002 ms): close(fd: 1                   ) = 0
  1000.485 (   0.001 ms): close(fd: 2                   ) = 0
  1000.494 (   0.000 ms): exit_group(                   )
[root@jouet linux]#

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: http://lkml.kernel.org/n/tip-ecbzgmu2ni6glc6zkw8p1zmx@git.kernel.org
Fixes: 752fde44 ("perf trace: Support interrupted syscalls")
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Not used at all, we need just the entry_time to calculate the syscall
duration.

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: http://lkml.kernel.org/n/tip-js6r09zdwlzecvaei7t4l3vd@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In the perf wiki todo-list[1], there is an entry regarding initial-delay
and 'perf trace'; the following small patch tries to fulfill this point.
It has been generated against the branch tip/perf/core.

It has only been implemented in the "trace__run" case.

Ex.:

  $ sudo strace -- ./perf trace --delay 5 sleep 1 2>&1
  ...
  fcntl(7, F_SETFL, O_RDONLY|O_NONBLOCK)  = 0
  ioctl(7, PERF_EVENT_IOC_ID, 0x7ffc8fd35718) = 0
  ioctl(11, PERF_EVENT_IOC_SET_OUTPUT, 0x7) = 0
  fcntl(11, F_SETFL, O_RDONLY|O_NONBLOCK) = 0
  ioctl(11, PERF_EVENT_IOC_ID, 0x7ffc8fd35718) = 0
  write(6, "\0", 1)                       = 1
  close(6)                                = 0
  nanosleep({0, 5000000}, NULL)           = 0  # DELAY OF 5 MS BEFORE ENABLING THE EVENTS
  ioctl(3, PERF_EVENT_IOC_ENABLE, 0)      = 0
  ioctl(4, PERF_EVENT_IOC_ENABLE, 0)      = 0
  ioctl(5, PERF_EVENT_IOC_ENABLE, 0)      = 0
  ioctl(7, PERF_EVENT_IOC_ENABLE, 0)      = 0
  ...

[1]: https://perf.wiki.kernel.org/index.php/TodoSigned-off-by: NAlexis Berlemont <alexis.berlemont@gmail.com>
Suggested-and-Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161010054328.4028-2-alexis.berlemont@gmail.com
[ Add entry to the manpage, cut'n'pasted from stat's and record's ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Making function perf_evsel__append_filter() static and introducing a new
tracepoint specific function to append filters.  That way we eliminate
redundant code and avoid formatting mistake.
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1474037045-31730-3-git-send-email-mathieu.poirier@linaro.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>