That is the case of _text on s390, and we have some functions that return an
address, using address zero to report problems, oops.

This would lead the symbol loading routines to not use "_text" as the reference
relocation symbol, or the first symbol for the kernel, but use instead
"_stext", that is at the same address on x86_64 and others, but not on s390:

  [acme@localhost perf-4.11.0-rc6]$ head -15 /proc/kallsyms
  0000000000000000 T _text
  0000000000000418 t iplstart
  0000000000000800 T start
  000000000000080a t .base
  000000000000082e t .sk8x8
  0000000000000834 t .gotr
  0000000000000842 t .cmd
  0000000000000846 t .parm
  000000000000084a t .lowcase
  0000000000010000 T startup
  0000000000010010 T startup_kdump
  0000000000010214 t startup_kdump_relocated
  0000000000011000 T startup_continue
  00000000000112a0 T _ehead
  0000000000100000 T _stext
  [acme@localhost perf-4.11.0-rc6]$

Which in turn would make 'perf test vmlinux' to fail because it wouldn't find
the symbols before "_stext" in kallsyms.

Fix it by using the return value only for errors and storing the
address, when the symbol is successfully found, in a provided pointer
arg.

Before this patch:

After:

  [acme@localhost perf-4.11.0-rc6]$ tools/perf/perf test -v 1
   1: vmlinux symtab matches kallsyms            :
  --- start ---
  test child forked, pid 40693
  Looking at the vmlinux_path (8 entries long)
  Using /usr/lib/debug/lib/modules/3.10.0-654.el7.s390x/vmlinux for symbols
  ERR : 0: _text not on kallsyms
  ERR : 0x418: iplstart not on kallsyms
  ERR : 0x800: start not on kallsyms
  ERR : 0x80a: .base not on kallsyms
  ERR : 0x82e: .sk8x8 not on kallsyms
  ERR : 0x834: .gotr not on kallsyms
  ERR : 0x842: .cmd not on kallsyms
  ERR : 0x846: .parm not on kallsyms
  ERR : 0x84a: .lowcase not on kallsyms
  ERR : 0x10000: startup not on kallsyms
  ERR : 0x10010: startup_kdump not on kallsyms
  ERR : 0x10214: startup_kdump_relocated not on kallsyms
  ERR : 0x11000: startup_continue not on kallsyms
  ERR : 0x112a0: _ehead not on kallsyms
  <SNIP warnings>
  test child finished with -1
  ---- end ----
  vmlinux symtab matches kallsyms: FAILED!
  [acme@localhost perf-4.11.0-rc6]$

After:

  [acme@localhost perf-4.11.0-rc6]$ tools/perf/perf test -v 1
   1: vmlinux symtab matches kallsyms            :
  --- start ---
  test child forked, pid 47160
  <SNIP warnings>
  test child finished with 0
  ---- end ----
  vmlinux symtab matches kallsyms: Ok
  [acme@localhost perf-4.11.0-rc6]$
Reported-by: Michael Petlan <mpetlan@redhat.com>
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-9x9bwgd3btwdk1u51xie93fz@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Both had copies originating from git.git, move those to
tools/lib/string.c, getting both tools/lib/subcmd/ and tools/perf/ to
use it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-uidwtticro1qhttzd2rkrkg1@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Its basically to do units handling, so move to a more appropriately
named object.

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-90ob9vfepui24l8l2makhd9u@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

No need to pollute util.h with this.

Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-kec0chbdtgrd71o3oi2kz2zt@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

This is a perl specific hack, so move it from util.h to where perl
headers are used.

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-4igctbinuom2sr6g4b03jqht@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Just one more step into splitting util.[ch] to reduce the includes hell.

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-navarr9mijkgwgbzu464dwam@git.kernel.orgSigned-off-by: Arnaldo 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: Arnaldo Carvalho de Melo <acme@redhat.com>

Where they belong.

Link: http://lkml.kernel.org/n/tip-94m3dziejxgo7k0488q3mqjm@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-core-for-mingo-4.12-20170424' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

User visible changes:

 - Fix display of data source snoop indication in 'perf mem' (Andi Kleen)

 - Fix the code to strip command name from /proc/PID/stat (Jiri Olsa)

Infrastructure changes:

 - Continue the disentanglement of headers, specially util.h (Arnaldo Carvalho de Melo)

 - Synchronize some header files with the kernel (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Recent commit broke command name strip in perf_event__get_comm_ids
function. It replaced left to right search for '\n' with rtrim, which
actually does right to left search. It occasionally caught earlier '\n'
and kept trash in the command name.

Keeping the ltrim, but moving back the left to right '\n' search
instead of the rtrim.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Taeung Song <treeze.taeung@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Yao Jin <yao.jin@linux.intel.com>
Fixes: bdd97ca6 ("perf tools: Refactor the code to strip command name with {l,r}trim()")
Link: http://lkml.kernel.org/r/20170420092430.29657-1-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To catch changes made in:

  90218ac7 ("x86/cpufeature: Detect CPUID faulting support")

No changes needed in the tools using this file at this time.

Cc: Kyle Huey <me@kylehuey.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/n/tip-qiqsj5qg2ljbsbfre2zaf9v4@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Just a minor fix done in:

  Fixes: 26a37ab3 ("x86/mce: Fix copy/paste error in exception table entries")

Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/n/tip-ni9jzdd5yxlail6pq8cuexw2@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To get the changes in the commit Fixes: 3209f68b ("statx: Include a
mask for stx_attributes in struct statx")

Silencing this perf build warning:

  Warning: tools/include/uapi/linux/stat.h differs from kernel

No need to change the statx syscall beautifiers in 'perf trace' at this
time.

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-y8bgiyzuvura62lffvh1zbg9@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Removing various instances of unnecessary includes, reducing the maze of
header dependencies.

Link: http://lkml.kernel.org/n/tip-hwu6eyuok9pc57alookyzmsf@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The util/event.h header needs PERF_ALIGN(), but wasn't including
linux/kernel.h, where it is defined, instead it was getting it by
luck by including map.h, which it doesn't need at all.

Fix it by including the right header.

Link: http://lkml.kernel.org/n/tip-nf3t9blzm5ncoxsczi8oy9mx@git.kernel.orgSigned-off-by: Arnaldo 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: Arnaldo Carvalho de Melo <acme@redhat.com>

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

Link: http://lkml.kernel.org/n/tip-xxtdsl6nsna82j7puwbdjqhs@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Some, like prune_packed_objects() are clearly git specific, others
don't have implementations and some are used in just one place, make
them static.

Link: http://lkml.kernel.org/n/tip-faj3c5dnttf3hurv4pujut8n@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Not needed in this header, added to the places that need strdup,
strcmp and a few other prototypes.

Link: http://lkml.kernel.org/n/tip-t24yy85xnlv55kyosrum2ubs@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Not needed in this header, added to the places that need 'struct
winsize' and the ioctl defines.

Link: http://lkml.kernel.org/n/tip-2pznlli3146y4242otlcm70m@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Link: http://lkml.kernel.org/n/tip-sb2zu21d6h42e5qnsrtl6wuu@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

As it is going away from util.h, where it is not needed.

This is mostly for things like MAXPATHLEN, MAX() and MIN(), these later
two probably should go away in favor of its kernel sources replacements.

Link: http://lkml.kernel.org/n/tip-z1666f3fl3fqobxvjr5o2r39@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Where they belong, no point in leaving those in the generic "util"
files.

Link: http://lkml.kernel.org/n/tip-ljx3iiip1hlfa7a7apjem7ph@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Out of util.h, the implementations were already in separate files, that
are built conditionally.

Link: http://lkml.kernel.org/n/tip-0ur7szxsb59f8758kfe63prb@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

'perf mem report' doesn't display the data source snoop indication correctly.

In the kernel API the definition is:

  #define PERF_MEM_SNOOP_NONE     0x02 /* no snoop */
  #define PERF_MEM_SNOOP_HIT      0x04 /* snoop hit */
  #define PERF_MEM_SNOOP_MISS     0x08 /* snoop miss */

but the table used by the perf tools exchanged "Hit" and "Miss":

        "None",
        "Miss",
        "Hit",

Fix the table in perf.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20170419174940.13641-1-andi@firstfloor.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Two more out of util.h.

Link: http://lkml.kernel.org/n/tip-polkuxm1cpr06lbgue5pyqum@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

No need to have this polluting util.h, it was polluted enough already.

Link: http://lkml.kernel.org/n/tip-wfdidqlwbvi5y0s61kv6z2gn@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We already have a header for time utilities, so use it.

Link: http://lkml.kernel.org/n/tip-sijzpbvutlg0c3oxn49hy9ca@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Out of util.h, to disentangle it 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-vpksyj3w5fk9t8s6mxmkajyr@git.kernel.orgSigned-off-by: Arnaldo 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: Arnaldo Carvalho de Melo <acme@redhat.com>

No need to drag the headers, helps in untangling them and reducing build
time.

Link: http://lkml.kernel.org/n/tip-l8soqph92duyw5jdha0fij8b@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-core-for-mingo-4.12-20170419' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core cleanups from Arnaldo Carvalho de Melo:

 - Introduce new header files out of the hodge-podge that util/util.h
   became, trying to disentangle the includes hell that all C projects
   end up growing. This should help in build times, as changes to
   seemingly unrelated files (util.h included tons of headers) won't
   trigger a rebuild of most object files.

 - Use equivalent facilities found in the kernel source code base
   originated tools/include/ header files, such as __stringify(),
   ARRAY_SIZE, that has extra checks (__must_be_array()), etc.

 - For that get some more files from the kernel sources, like
   include/linux/bug.h, some just with the bits needed at this time.

 - Use the headers where facilities declared in them are used, such
   as PRIxu(32,64) macros (inttypes.h), errno defines (errno.h), etc.

 - Remove various leftovers from the initial code base we copied from
   git.git: FLEX_ARRAY, etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Remnants from the git codebase.

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-kwaez3uxo1w9f8v5r7etl0w6@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The users of regex and fnmatch functions should include those headers
instead.

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-ixzm5kuamsq1ixbkuv6kmwzj@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The files using the dirent.h routines should instead include it,
reducing the includes hell that lead to longer build times.

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-42g2f4z6nfg7mdb2ae97n7tj@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Those args _are_ being used.

Link: http://lkml.kernel.org/n/tip-yi9s00ki1i1tcc704v042957@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Instead of getting it out of luck from util.h, where it isn't needed at
all.

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-0bqugg5lc5ksla1v4m0dnmc1@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When we switched to the kernel's roundup_pow_of_two we forgot to remove
this include from util.h, do it now.

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: 91529834 ("perf evlist: Use roundup_pow_of_two")
Link: http://lkml.kernel.org/n/tip-kfye5rxivib6155cltx0bw4h@git.kernel.orgSigned-off-by: Arnaldo 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: Arnaldo Carvalho de Melo <acme@redhat.com>