Rename enum dso_kernel_type to enum dso_space_type, which seems like
better fit.

Committer notes:

This is used with 'struct dso'->kernel, which once was a boolean, so
DSO_SPACE__USER is zero, !zero means some sort of kernel space, be it
the host kernel space or a guest kernel space.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In the absence of any modules, no "modules" map is created, but there
are other executable pages to map, due to eBPF JIT, kprobe or ftrace.
Map them by recognizing that the first "module" symbol is not
necessarily from a module, and adjust the map accordingly.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20200512121922.8997-10-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

After copying Arm64's perf archive with object files and perf.data file
to x86 laptop, the x86's perf kernel symbol resolution fails.  It
outputs 'unknown' for all symbols parsing.

This issue is root caused by the function elf__needs_adjust_symbols(),
x86 perf tool uses one weak version, Arm64 (and powerpc) has rewritten
their own version.  elf__needs_adjust_symbols() decides if need to parse
symbols with the relative offset address; but x86 building uses the weak
function which misses to check for the elf type 'ET_DYN', so that it
cannot parse symbols in Arm DSOs due to the wrong result from
elf__needs_adjust_symbols().

The DSO parsing should not depend on any specific architecture perf
building; e.g. x86 perf tool can parse Arm and Arm64 DSOs, vice versa.
And confirmed by Naveen N. Rao that powerpc64 kernels are not being
built as ET_DYN anymore and change to ET_EXEC.

This patch removes the arch specific functions for Arm64 and powerpc and
changes elf__needs_adjust_symbols() as a common function.

In the common elf__needs_adjust_symbols(), it checks an extra condition
'ET_DYN' for elf header type.  With this fixing, the Arm64 DSO can be
parsed properly with x86's perf tool.

Before:

  # perf script
  main 3258 1 branches:                0 [unknown] ([unknown]) => ffff800010c4665c [unknown] ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c46670 [unknown] ([kernel.kallsyms]) => ffff800010c4eaec [unknown] ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c4eaec [unknown] ([kernel.kallsyms]) => ffff800010c4eb00 [unknown] ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c4eb08 [unknown] ([kernel.kallsyms]) => ffff800010c4e780 [unknown] ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c4e7a0 [unknown] ([kernel.kallsyms]) => ffff800010c4eeac [unknown] ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c4eebc [unknown] ([kernel.kallsyms]) => ffff800010c4ed80 [unknown] ([kernel.kallsyms])

After:

  # perf script
  main 3258 1 branches:                0 [unknown] ([unknown]) => ffff800010c4665c coresight_timeout+0x54 ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c46670 coresight_timeout+0x68 ([kernel.kallsyms]) => ffff800010c4eaec etm4_enable_hw+0x3cc ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c4eaec etm4_enable_hw+0x3cc ([kernel.kallsyms]) => ffff800010c4eb00 etm4_enable_hw+0x3e0 ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c4eb08 etm4_enable_hw+0x3e8 ([kernel.kallsyms]) => ffff800010c4e780 etm4_enable_hw+0x60 ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c4e7a0 etm4_enable_hw+0x80 ([kernel.kallsyms]) => ffff800010c4eeac etm4_enable+0x2d4 ([kernel.kallsyms])
  main 3258 1 branches: ffff800010c4eebc etm4_enable+0x2e4 ([kernel.kallsyms]) => ffff800010c4ed80 etm4_enable+0x1a8 ([kernel.kallsyms])

v3: Changed to check for ET_DYN across all architectures.

v2: Fixed Arm64 and powerpc native building.
Reported-by: NMike Leach <mike.leach@linaro.org>
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Reviewed-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: NJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Enrico Weigelt <info@metux.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Link: http://lore.kernel.org/lkml/20200306015759.10084-1-leo.yan@linaro.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When a map is create to represent the main kernel area (vmlinux) with
map__new2() we allocate an extra area to store a pointer to the 'struct
maps' for the kernel maps, so that we can access that struct when
loading ELF files or kallsyms, as we will need to split it in multiple
maps, one per kernel module or ELF section (such as ".init.text").

So when map->dso->kernel is non-zero, it is expected that
map__kmap(map)->kmaps to be set to the tree of kernel maps (modules,
chunks of the main kernel, bpf progs put in place via
PERF_RECORD_KSYMBOL, the main kernel).

This was not the case when we were splitting the main kernel into chunks
for its ELF sections, which ended up making 'perf report --children'
processing a perf.data file with callchains to trip on
__map__is_kernel(), when we press ENTER to see the popup menu for main
histogram entries that starts at a symbol in the ".init.text" ELF
section, e.g.:

-    8.83%     0.00%  swapper     [kernel.vmlinux].init.text  [k] start_kernel
     start_kernel
     cpu_startup_entry
     do_idle
     cpuidle_enter
     cpuidle_enter_state
     intel_idle

Fix it.
Reviewed-by: NJiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/20191218190120.GB13282@kernel.org/Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

One more step in the merge of 'struct maps' with 'struct map_groups'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-9ibtn3vua76f934t7woyf26w@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

And pick the shortest name: 'struct maps'.

The split existed because we used to have two groups of maps, one for
functions and one for variables, but that only complicated things,
sometimes we needed to figure out what was at some address and then had
to first try it on the functions group and if that failed, fall back to
the variables one.

That split is long gone, so for quite a while we had only one struct
maps per struct map_groups, simplify things by combining those structs.

First patch is the minimum needed to merge both, follow up patches will
rename 'thread->mg' to 'thread->maps', etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-hom6639ro7020o708trhxh59@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To test that that function is being called I just added a probe on that
place, enabled it via 'perf trace' asking for at most 16 levels of
backtraces, system wide, and then ran 'perf top' on another xterm,
voilà:

  # perf probe -x ~/bin/perf dso__process_kernel_symbol
  Added new event:
    probe_perf:dso__process_kernel_symbol (on dso__process_kernel_symbol in /home/acme/bin/perf)

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

  	perf record -e probe_perf:dso__process_kernel_symbol -aR sleep 1

  # perf trace -e probe_perf:dso__process_kernel_symbol/max-stack=16/ --max-events=2
  # perf trace -e probe_perf:dso__process_kernel_symbol/max-stack=16/ --max-events=2
       0.000 :17345/17345 probe_perf:dso__process_kernel_symbol(__probe_ip: 5680224)
                                         dso__process_kernel_symbol (/home/acme/bin/perf)
                                         dso__load_vmlinux (/home/acme/bin/perf)
                                         dso__load_vmlinux_path (/home/acme/bin/perf)
                                         dso__load (/home/acme/bin/perf)
                                         map__load (/home/acme/bin/perf)
                                         thread__find_map (/home/acme/bin/perf)
                                         machine__resolve (/home/acme/bin/perf)
                                         deliver_event (/home/acme/bin/perf)
                                         __ordered_events__flush.part.0 (/home/acme/bin/perf)
                                         process_thread (/home/acme/bin/perf)
                                         start_thread (/usr/lib64/libpthread-2.29.so)
       0.064 :17345/17345 probe_perf:dso__process_kernel_symbol(__probe_ip: 5680224)
                                         dso__process_kernel_symbol (/home/acme/bin/perf)
                                         dso__load_vmlinux (/home/acme/bin/perf)
                                         dso__load_vmlinux_path (/home/acme/bin/perf)
                                         dso__load (/home/acme/bin/perf)
                                         map__load (/home/acme/bin/perf)
                                         thread__find_map (/home/acme/bin/perf)
                                         machine__resolve (/home/acme/bin/perf)
                                         deliver_event (/home/acme/bin/perf)
                                         __ordered_events__flush.part.0 (/home/acme/bin/perf)
                                         process_thread (/home/acme/bin/perf)
                                         start_thread (/usr/lib64/libpthread-2.29.so)
  #
  # perf stat -e probe_perf:dso__process_kernel_symbol
  ^C
   Performance counter stats for 'system wide':

           107,308      probe_perf:dso__process_kernel_symbol

       8.215399813 seconds time elapsed
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-5fy66x5hr5ct9pmw84jkiwvm@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Further reducing the util.c hodgepodge files.

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-0i62zh7ok25znibyebgq0qs4@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This was being obtained only indirectly, by luck.

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-xeolxwr3iftwfw9kmw26shfe@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Check that it is not needed and remove, fixing up some fallout for
places where it was only serving to get something else.

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-9h6dg6lsqe2usyqjh5rrues4@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

So that we can remove dso.h from symbol.h and reduce the header
dependency tree.

Fixup cases where struct dso guts are needed but were obtained via
symbol.h, indirectly.

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-ip683cegt306ncu3gsz7ii21@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

No need to have it generally available in such a critical header as
symbol.h.

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-es1ufxv7bihiumytn5dm3drn@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To allow for destructors to check if they're operating on a object still
in a list, and to avoid going from use after free list entries into
still valid, or even also other already removed from list entries.

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-deh17ub44atyox3j90e6rksu@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In places where the equivalent was already being done, i.e.:

   free(a);
   a = NULL;

And in placs where struct members are being freed so that if we have
some erroneous reference to its struct, then accesses to freed members
will result in segfaults, which we can detect faster than use after free
to areas that may still have something seemingly valid.

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-jatyoofo5boc1bsvoig6bb6i@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Eroding a bit more the tools/perf/util/util.h hodpodge header.

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-natazosyn9rwjka25tvcnyi0@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Part of the erosion of util/util.h, that will lose its include stdlib.h,
we need to add it to places where it is needed but was getting it
indirectly.

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-1imnqezw99ahc07fjeb51qby@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We got the sane_ctype.h headers from git and kept using it so far, but
since that code originally came from the kernel sources to the git
sources, perhaps its better to just use the one in the kernel, so that
we can leverage tools/perf/check_headers.sh to be notified when our copy
gets out of sync, i.e. when fixes or goodies are added to the code we've
copied.

This will help with things like tools/lib/string.c where we want to have
more things in common with the kernel, such as strim(), skip_spaces(),
etc so as to go on removing the things that we have in tools/perf/util/
and instead using the code in the kernel, indirectly and removing things
like EXPORT_SYMBOL(), etc, getting notified when fixes and improvements
are made to the original code.

Hopefully this also should help with reducing the difference of code
hosted in tools/ to the one in the kernel proper.

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-7k9868l713wqtgo01xxygn12@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Continuing to untangle the headers, we're about to remove the old odd
baggage that is tools/perf/util/include/linux/ctype.h.

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-gapezcq3p8bzrsi96vdtq0o0@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Variable 'err' is defined but never used in function symsrc__init(),
remove it and directly return -1 at the end of the function.
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190530093801.20510-1-leo.yan@linaro.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

And since machine.h only needs what is in there, make it stop including
map.h and instead include this newly introduced map_groups.h instead.

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-dbob25fv5rp2rjpwlnterf38@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Lots of places get the map.h file indirectly, and since we're going to
remove it from machine.h, then those need to include it directly, do it
now, before we remove that dep.

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-ob8jehdjda8h5jsrv9dqj9tf@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When perf is built with the annobin plugin (RHEL8 build) extra symbols
are added to its binary:

  # nm perf | grep annobin | head -10
  0000000000241100 t .annobin_annotate.c
  0000000000326490 t .annobin_annotate.c
  0000000000249255 t .annobin_annotate.c_end
  00000000003283a8 t .annobin_annotate.c_end
  00000000001bce18 t .annobin_annotate.c_end.hot
  00000000001bce18 t .annobin_annotate.c_end.hot
  00000000001bc3e2 t .annobin_annotate.c_end.unlikely
  00000000001bc400 t .annobin_annotate.c_end.unlikely
  00000000001bce18 t .annobin_annotate.c.hot
  00000000001bce18 t .annobin_annotate.c.hot
  ...

Those symbols have no use for report or annotation and should be
skipped.  Moreover they interfere with the DWARF unwind test on the PPC
arch, where they are mixed with checked symbols and then the test fails:

  # perf test dwarf -v
  59: Test dwarf unwind                                     :
  --- start ---
  test child forked, pid 8515
  unwind: .annobin_dwarf_unwind.c:ip = 0x10dba40dc (0x2740dc)
  ...
  got: .annobin_dwarf_unwind.c 0x10dba40dc, expecting test__arch_unwind_sample
  unwind: failed with 'no error'

The annobin symbols are defined as NOTYPE/LOCAL/HIDDEN:

  # readelf -s ./perf | grep annobin | head -1
    40: 00000000001bce4f     0 NOTYPE  LOCAL  HIDDEN    13 .annobin_init.c

They can still pass the check for the label symbol. Adding check for
HIDDEN and INTERNAL (as suggested by Nick below) visibility and filter
out such symbols.

>   Just to be awkward, if you are going to ignore STV_HIDDEN
>   symbols then you should probably also ignore STV_INTERNAL ones
>   as well...  Annobin does not generate them, but you never know,
>   one day some other tool might create some.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nick Clifton <nickc@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190128133526.GD15461@kravaSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Those aren't present in Alpine Linux 3.4 to edge, so provide fallback
defines to get the next patch building there keeping the build
bisectable.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nick Clifton <nickc@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/n/tip-03cg3gya2ju4ba2x6ibb9fuz@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Using the sh_entsize for both values isn't correct.  It happens to be
correct on x86...

For both 32-bit and 64-bit sparc, there are four PLT entries in the PLT
section.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: David Tolnay <dtolnay@gmail.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Li Bin <huawei.libin@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: zhangmengting@huawei.com
Fixes: b2f76050 ("perf symbols: Fix plt entry calculation for ARM and AARCH64")
Link: http://lkml.kernel.org/r/20181017.120859.2268840244308635255.davem@davemloft.netSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

With this, perf buildid-cache will save SDT markers with reference
counter in probe cache. Perf probe will be able to probe markers
having reference counter. Ex,

  # readelf -n /tmp/tick | grep -A1 loop2
    Name: loop2
    ... Semaphore: 0x0000000010020036

  # ./perf buildid-cache --add /tmp/tick
  # ./perf probe sdt_tick:loop2
  # ./perf stat -e sdt_tick:loop2 /tmp/tick
    hi: 0
    hi: 1
    hi: 2
    ^C
     Performance counter stats for '/tmp/tick':
                 3      sdt_tick:loop2
       2.561851452 seconds time elapsed

Link: http://lkml.kernel.org/r/20180820044250.11659-5-ravi.bangoria@linux.ibm.comAcked-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Acked-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: NSong Liu <songliubraving@fb.com>
Tested-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NRavi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

x86 PTI entry trampolines all map to the same physical page. If that is
reflected in the program headers of /proc/kcore, then do the same for the
copy of kcore.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-18-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Identify and copy any sections for x86 PTI entry trampolines.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-17-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In preparation to add more program headers, get rid of kernel_map and
modules_map by moving ->kernel_map and ->modules_map to newly allocated
entries in the ->phdrs list.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-16-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In preparation to add more program headers, iterate phdrs instead of
assuming there is only one for the kernel text and one for the modules.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-15-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In preparation to add more program headers, layout the relative offset
of each section.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-14-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In preparation to add more program headers, calculate offset from the
number of phdrs.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-13-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In preparation to add more program headers, keep a count of phdrs.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-12-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently, kcore_copy makes 2 program headers, one for the kernel text
(namely kernel_map) and one for the modules (namely modules_map). Now
more program headers are needed, but treating each program header as a
special case results in much more code.

Instead, in preparation to add more program headers, change to keep
program header data (phdr_data) in a list.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-11-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

More should be done to split this function, removing stuff map
relocation steps from the actual symbol table loading.

Arch specific stuff also should go elsewhere, to tools/arch/ and
we should have it keyed by data from the perf_env either in the
perf.data header or from the running environment.

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-236gyo6cx6iet90u3uc01cws@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We can plain use the an else to the if block that is right after that
goto, so simplify 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: https://lkml.kernel.org/n/tip-vnpc2rakf6vc98pcl5z1cfrg@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Remove the split of symbol tables for data (MAP__VARIABLE) and for
functions (MAP__FUNCTION), its unneeded and there were various places
doing two lookups to find a symbol, so simplify this.

We still will consider only the symbols that matched the filters in
place, i.e. see the (elf_(sec,sym)|symbol_type)__filter() routines in
the patch, just so that we consider only the same symbols as before,
to reduce the possibility of regressions.

All the tests on 50-something build environments, in varios versions
of lots of distros and cross build environments were performed without
build regressions, as usual with all pull requests the other tests were
also performed: 'perf test' and 'make -C tools/perf build-test'.

Also this was done at a great granularity so that regressions can be
bisected more easily.

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-hiq0fy2rsleupnqqwuojo1ne@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

map->type is going away, we can derive it from map->prot, so use
the same logic as in the kernel's arch/arm/kernel/module.c file:

  ELF32_ST_TYPE(sym->st_info) == STT_FUNC && !(sym->st_value & 1))

This was introduced in b2f8fb23 ("perf symbols: Fix annotation of
thumb code"), that fix is maintained with this change.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Dave Martin <dave.martin@linaro.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Dr. David Alan Gilbert <david.gilbert@linaro.org>
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-us590h81uqgxaumucfttqj50@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In 39b12f78 ("perf tools: Make it possible to read object code from
vmlinux") we special case MAP__FUNCTION maps inconsistently, the first
test tests the map type while the following tests added by this patch
don't do that, be consistent and elliminate this special case.

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-khmi5jccpcwqa9nybefluzqp@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

There is code that needs to see if a resolved address is a function, so,
since we're going to ditch the MAP__{FUNCTION,VARIABLE} split, store
that info in the per symbol struct.

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-9ugwxz0i8ryg5702rx8u5q6z@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Replacing equivalent, the equivalent and longer variation:

	 symbol__is_a(type, MAP__FUNCTION);

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-9t3dqogher54owfl9o2mir52@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>