While trying to reduce util.[ch] I noticed that fetch_kernel_version()
and fetch_ubuntu_kernel_version() do lots of operations only to check if
they are needed, i.e. it checks if the pointer where to return the
kernel version is NULL only after obtaining the kernel version from
/proc/version_signature or by parsing the results from uname().

Do it earlier not to confuse people reading this code in the future :-)

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-i94qwyekk4tzbu0b9ce1r1mz@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

And make it static, nobody else uses it, if we ever need it in more
places we can carve a new source file for process related methods,
for now lets reduce util.{c,h} a tad more.

Link: http://lkml.kernel.org/n/tip-zgb28rllvypjibw52aaz9p15@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-core-for-mingo-4.13-20170719' 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:

- Allow adding and removing fields to the default 'perf script' columns,
  using + or - as field prefixes to do so (Andi Kleen)

- Display titles in left frame in the annotate browser (Jin Yao)

- Allow resolving the DSO name with 'perf script -F brstack{sym,off},dso'
  (Mark Santaniello)

- Support function filtering in 'perf ftrace' (Namhyung Kim)

- Allow specifying function call depth in 'perf ftrace' (Namhyumg Kim)

Infrastructure changes:

- Adopt __noreturn, __printf, __scanf, noinline, __packed and __aligned
  __alignment__(()) markers, to make the tools/ source code base to be
  more compact and look more like kernel code (Arnaldo Carvalho de Melo)

- Remove unnecessary check in annotate_browser_write() (Jin Yao)

- Return arch from symbol__disassemble() so that callers, such as
  the annotate TUI browser to use arch specific formattings, such
  as the upcoming instruction micro-op fusion on Intel Core (Jin Yao)

- Remove superfluous check before use in the coresight code base (Kim
  Phillips)

- Remove unused SAMPLE_SIZE defines and BTS priv array (Kim Phillips)

- Error handling fix/tidy ups in 'perf config' (Taeung Song)

- Avoid error in the BPF proggie built with clang in 'perf test llvm'
  when PROFILE_ALL_BRANCHES is set (Wang Nan)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Signed-off-by: NIngo Molnar <mingo@kernel.org>

To simplify the code related to 'ret' variable in cmd_config(),
initialize 'ret' with -1 instead of 0 and use goto to perform resource
release at the end of the function, setting ret to zero just before the
out_err label, as usual in the kernel sources.
Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1497671202-20495-1-git-send-email-treeze.taeung@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

show_spec_config() and set_config() can be called multiple times
in the loop in cmd_config().

However, The error cases of them wasn't checked, so fix it.
Reported-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1497671197-20450-1-git-send-email-treeze.taeung@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The -D/--graph-depth option is to set max graph depth.  The following
example traces max 2-depth of page fault handler.

  $ sudo perf ftrace -G __do_page_fault -D 2 -- hello
   ...
   0)               |  __do_page_fault() {
   0)   0.063 us    |    down_read_trylock();
   0)   0.251 us    |    find_vma();
   0)   5.374 us    |    handle_mm_fault();
   0)   0.054 us    |    up_read();
   0)   7.463 us    |  }
   ...
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170618142302.25390-4-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The -T/--trace-funcs and -N/--notrace-funcs options are to specify
functions to enable/disable tracing dynamically.

The -G/--graph-funcs and -g/--nograph-funcs options are to set filters
for function graph tracer.

For example, to trace fault handling functions only:

  $ sudo perf ftrace -T *fault hello
   0)               |  __do_page_fault() {
   0)               |    handle_mm_fault() {
   0)   2.117 us    |      __handle_mm_fault();
   0)   3.627 us    |    }
   0)   7.811 us    |  }
   0)               |  __do_page_fault() {
   0)               |    handle_mm_fault() {
   0)   2.014 us    |      __handle_mm_fault();
   0)   2.424 us    |    }
   0)   2.951 us    |  }
   ...

To trace all functions executed in __do_page_fault:

  $ sudo perf ftrace -G __do_page_fault hello
   2)               |  __do_page_fault() {
   3)   0.060 us    |    down_read_trylock();
   3)               |    find_vma() {
   3)   0.075 us    |      vmacache_find();
   3)   0.053 us    |      vmacache_update();
   3)   1.246 us    |    }
   3)               |    handle_mm_fault() {
   3)   0.063 us    |      __rcu_read_lock();
   3)   0.056 us    |      mem_cgroup_from_task();
   3)   0.057 us    |      __rcu_read_unlock();
   3)               |      __handle_mm_fault() {
   3)               |        filemap_map_pages() {
   3)   0.058 us    |          __rcu_read_lock();
   3)               |          alloc_set_pte() {
   ...

But don't want to show details in handle_mm_fault:

  $ sudo perf ftrace -G __do_page_fault -g handle_mm_fault hello
   3)               |  __do_page_fault() {
   3)   0.049 us    |    down_read_trylock();
   3)               |    find_vma() {
   3)   0.048 us    |      vmacache_find();
   3)   0.041 us    |      vmacache_update();
   3)   0.680 us    |    }
   3)   0.036 us    |    up_read();
   3)   4.547 us    |  } /* __do_page_fault */
   ...
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170618142302.25390-3-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The 'perf ftrace' command fails to reset tracer after finishing
recording like below:

  $ sudo perf ftrace -v hello
  write 'nop' to tracing/current_tracer failed: Device or resource busy
  ...

This is because the trace_pipe file is open in pager process.  Move the
pager setup to before opening the file.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Fixes: 58335964 ("perf ftrace: Use pager for displaying result")
Link: http://lkml.kernel.org/r/20170618142302.25390-2-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It'd be better for debugging to show an error message when it fails to
setup ftrace for some reason.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170618142302.25390-1-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The idea here is to make AutoFDO easier in cloud environment with ASLR.
It's easiest to show how this is useful by example. I built a small test
akin to "while(1) { do_nothing(); }" where the do_nothing function is
loaded from a dso:

  $ cat burncpu.cpp
  #include <dlfcn.h>

  int main() {
    void* handle = dlopen("./dso.so", RTLD_LAZY);
    if (!handle) return -1;

    typedef void (*fp)();
    fp do_nothing = (fp) dlsym(handle, "do_nothing");

    while(1) {
      do_nothing();
    }
  }

  $ cat dso.cpp
  extern "C" void do_nothing() {}

  $ cat build.sh
  #!/bin/bash
  g++ -shared dso.cpp -o dso.so
  g++ burncpu.cpp -o burncpu -ldl

I sampled the execution of this program with perf record -b.

Using the existing "brstack,dso", we get absolute addresses that are
affected by ASLR, and could be different on different hosts. The address
does not uniquely identify a branch/target in the binary:

  $ perf script -F brstack,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
  0x7f967139b6aa(/tmp/burncpu/dso.so)/0x4006b1(/tmp/burncpu/exe)/P/-/-/0

Using the existing "brstacksym,dso" is a little better, because the
symbol plus offset and dso name *does* uniquely identify a branch/target
in the binary.  Ultimately, however, AutoFDO wants a simple offset into
the binary, so we'd have to undo all the work perf did to symbolize in
the first place:

  $ perf script -F brstacksym,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
  do_nothing+0x5(/tmp/burncpu/dso.so)/main+0x44(/tmp/burncpu/exe)/P/-/-/0

With the new "brstackoff,dso" we get what we need: a simple offset into a
specific dso/binary that uniquely identifies a branch/target:
  $ perf script -F brstackoff,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
  0x6aa(/tmp/burncpu/dso.so)/0x4006b1(/tmp/burncpu/exe)/P/-/-/0
Signed-off-by: NMark Santaniello <marksan@fb.com>
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/20170619163825.2012979-2-marksan@fb.com
[ Updated documentation about 'brstackoff' using text from above ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Perf script can report the dso for "addr" and "ip" fields.

This adds the same support for the "brstack" and "brstacksym" fields.
This can be helpful for AutoFDO: we can ignore LBR entries unless the
source and target address are both in the target module we are about to
build.

I built a small test akin to "while(1) { do_nothing(); }" where the
do_nothing function is loaded from a dso:

  $ cat burncpu.cpp
  #include <dlfcn.h>

  int main() {
    void* handle = dlopen("./dso.so", RTLD_LAZY);
    if (!handle) return -1;

    typedef void (*fp)();
    fp do_nothing = (fp) dlsym(handle, "do_nothing");

    while(1) {
      do_nothing();
    }
  }

  $ cat dso.cpp
  extern "C" void do_nothing() {}

  $ cat build.sh
  #!/bin/bash
  g++ -shared dso.cpp -o dso.so
  g++ burncpu.cpp -o burncpu -ldl

I sampled the execution with perf record -b.  Using the new perf script
functionality I can easily find cases where there was a transition from one
dso to another:

  $ perf record -a -b -- sleep 5
  [ perf record: Woken up 55 times to write data ]
  [ perf record: Captured and wrote 18.815 MB perf.data (43593 samples) ]

  $ perf script -F brstack,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
  0x7f967139b6aa(/tmp/burncpu/dso.so)/0x4006b1(/tmp/burncpu/exe)/P/-/-/0

  $ perf script -F brstacksym,dso | sed 's/\/0 /\/0\n/g' | grep burncpu | grep dso.so | head -n 1
  do_nothing+0x5(/tmp/burncpu/dso.so)/main+0x44(/tmp/burncpu/exe)/P/-/-/0
Signed-off-by: NMark Santaniello <marksan@fb.com>
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/20170619163825.2012979-1-marksan@fb.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The 'if' keyword is a define that expands to complex code when
CONFIG_PROFILE_ALL_BRANCHES is selected, which causes a 'perf test LLVM'
failure like:

  $ ./perf test LLVM
  35: LLVM search and compile                    :
  35.1: Basic BPF llvm compile                    : Ok
  35.2: kbuild searching                          : Ok
  35.3: Compile source for BPF prologue generation: FAILED!
  35.4: Compile source for BPF relocation         : Skip

The only affected test case is bpf-script-test-prologue.c
because it uses kernel headers and has 'if' inside.

This patch undefines 'if' to make it passes perf test.

More detailed analysis from a message in this thread, also by Wang:

The problem is caused by following relocation information:

  $ readelf -a ./llvmsubtest3
  ...
     [ 5] _ftrace_branch    PROGBITS         0000000000000000  00000260
          00000000000000a0  0000000000000000  WA       0     0     4
  ...
  Relocation section '.relfunc=null_lseek file->f_mode offset orig' at
  offset 0x490 contains 4 entries:
     Offset          Info           Type           Sym. Value    Sym. Name
  000000000038  000b00000001 unrecognized: 1       0000000000000000 _ftrace_branch
  0000000000b0  000b00000001 unrecognized: 1       0000000000000000 _ftrace_branch
  000000000128  000b00000001 unrecognized: 1       0000000000000000 _ftrace_branch
  0000000001c0  000b00000001 unrecognized: 1       0000000000000000 _ftrace_branch

  Relocation section '.rel_ftrace_branch' at offset 0x4d0 contains 8 entries:
     Offset          Info           Type           Sym. Value    Sym. Name
  000000000000  000200000001 unrecognized: 1       0000000000000000 .L__func__.bpf_func__n
  000000000008  000100000001 unrecognized: 1       0000000000000015 .L.str
  000000000028  000200000001 unrecognized: 1       0000000000000000 .L__func__.bpf_func__n
  000000000030  000100000001 unrecognized: 1       0000000000000015 .L.str
  000000000050  000200000001 unrecognized: 1       0000000000000000 .L__func__.bpf_func__n
  000000000058  000100000001 unrecognized: 1       0000000000000015 .L.str
  000000000078  000200000001 unrecognized: 1       0000000000000000 .L__func__.bpf_func__n
  000000000080  000100000001 unrecognized: 1       0000000000000015 .L.str
  ...

So I think the failure is because you enabled CONFIG_PROFILE_ALL_BRANCHES.

I can reproduce your buggy result by selecting
CONFIG_PROFILE_ALL_BRANCHES in my kbuild:

  $ ./perf test LLVM
  35: LLVM search and compile                    :
  35.1: Basic BPF llvm compile                    : Ok
  35.2: kbuild searching                          : Ok
  35.3: Compile source for BPF prologue generation: FAILED!
  35.4: Compile source for BPF relocation         : Skip

Simply undef CONFIG_PROFILE_ALL_BRANCHES in clang opts not working
because it is introduced by "#include <uapi/linux/fs.h>", which override
cmdline options. So I think the best way is to undefine 'if' inside BPF
script.
Reported-and-Tested-by: NThomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/20170620183203.2517-1-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In annotate browser, we will add support to check fused instructions.
While this is x86-specific feature so we need the annotate browser to
know what the arch it runs on.

symbol__disassemble() has figured out the arch. This patch just lets the
arch return from symbol__disassemble and save the arch in annotate
browser.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1497840958-4759-2-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

These defines were probably dragged in from sampling support in earlier
patches.  They can be put back when needed.
Signed-off-by: NKim Phillips <kim.phillips@arm.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170616112339.3fb6986e4ff33e353008244b@arm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The cs_etm_evsel variable is guaranteed to be set at this point in
cs_etm_recording_options().
Signed-off-by: NKim Phillips <kim.phillips@arm.com>
Acked-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20170615125521.80cc128dc856bc1f2e61b730@arm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To have a more compact way to ask the compiler to use a specific
alignment, making tools/ look more like kernel source code.

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-8jiem6ubg9rlpbs7c2p900no@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To have a more compact way to ask the compiler to not insert alignment
paddings in a struct, making tools/ look more like kernel source code.

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-byp46nr7hsxvvyc9oupfb40q@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To have a more compact way to ask the compiler not to inline a function
and to make tools/ source code look like kernel code.

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-bis4pqxegt6gbm5dlqs937tn@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Instead of defining __unused or redefining __maybe_unused.

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-4eleto5pih31jw1q4dypm9pf@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To have a more compact way to ask the compiler to perform scanf like
argument validation.

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-yzqrhfjrn26lqqtwf55egg0h@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To have a more compact way to ask the compiler to perform printf like
vargargs validation.

v2: Fixed up build on arm, squashing a patch by Kim Phillips, thanks!

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-dopkqmmuqs04cxzql0024nnu@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To have a more compact way to specify that a function doesn't return,
instead of the open coded:

	__attribute__((noreturn))

And use it instead of the tools/perf/ specific variation, NORETURN.

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-l0y144qzixcy5t4c6i7pdiqj@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

With 'perf script' it is common that we just want to add or remove a field.

Currently this requires figuring out the long list of default fields and
specifying them first, and then adding/removing the new field.

This patch adds a new + - syntax to merely add or remove fields,
that allows more succint and clearer command lines

For example to remove the comm field from PMU samples:

Previously

  $ perf script -F tid,cpu,time,event,sym,ip,dso,period | head -1
  swapper  0 [000] 504345.383126:          1 cycles:  ffffffff90060c66 native_write_msr ([kernel.kallsyms])

with the new syntax

  perf script -F -comm | head -1
  0 [000] 504345.383126:          1 cycles:  ffffffff90060c66 native_write_msr ([kernel.kallsyms])

The new syntax cannot be mixed with normal overriding.

v2: Fix example in description. Use tid vs pid. No functional changes.
v3: Don't skip initialization when user specified explicit type.
v4: Rebase. Remove empty line.

Committer testing:

  # perf record -a usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 1.748 MB perf.data (14 samples) ]

Without a explicit field list specified via -F, defaults to:

  # perf script | head -2
      perf 6338 [000] 18467.058607: 1 cycles: ffffffff89060c36 native_write_msr (/lib/modules/4.11.0-rc8+/build/vmlinux)
   swapper    0 [001] 18467.058617: 1 cycles: ffffffff89060c36 native_write_msr (/lib/modules/4.11.0-rc8+/build/vmlinux)
  #

Which is equivalent to:

  # perf script -F comm,tid,cpu,time,period,event,ip,sym,dso | head -2
      perf 6338 [000] 18467.058607: 1 cycles: ffffffff89060c36 native_write_msr (/lib/modules/4.11.0-rc8+/build/vmlinux)
   swapper    0 [001] 18467.058617: 1 cycles: ffffffff89060c36 native_write_msr (/lib/modules/4.11.0-rc8+/build/vmlinux)
  #

So if we want to remove the comm, as in your original example, we would have to
figure out the default field list and remove ' comm' from it:

  # perf script -F tid,cpu,time,period,event,ip,sym,dso | head -2
   6338 [000] 18467.058607: 1 cycles: ffffffff89060c36 native_write_msr (/lib/modules/4.11.0-rc8+/build/vmlinux)
      0 [001] 18467.058617: 1 cycles: ffffffff89060c36 native_write_msr (/lib/modules/4.11.0-rc8+/build/vmlinux)
  #

With your patch this becomes simpler, one can remove fields by prefixing them
with '-':

  # perf script -F -comm | head -2
  6338 [000] 18467.058607: 1 cycles: ffffffff89060c36 native_write_msr (/lib/modules/4.11.0-rc8+/build/vmlinux)
     0 [001] 18467.058617: 1 cycles: ffffffff89060c36 native_write_msr (/lib/modules/4.11.0-rc8+/build/vmlinux)
  #
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: NMilian Wolff <milian.wolff@kdab.com>
Link: http://lkml.kernel.org/r/20170602154810.15875-1-andi@firstfloor.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Signed-off-by: NTaeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1494241650-32210-1-git-send-email-treeze.taeung@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The annotate browser is divided into 2 frames. Left frame contains 3
columns (some platforms only have one column).

For example:

                   │26  int compute_flag()
                   │27  {
 22.80  1.20       │      sub    $0x8,%rsp
                   │25          int i;
                   │
                   │27          i = rand() % 2;
 22.78  1.20     1 │    → callq  rand@plt

While it's hard for user to understand what the data is.

This patch adds the titles "Percent", "IPC" and "Cycle" on columns.

Percent  IPC Cycle │
                   │25  __attribute__((noinline))
                   │26  int compute_flag()
                   │27  {
 22.80  1.20       │      sub    $0x8,%rsp
                   │25          int i;
                   │
                   │27          i = rand() % 2;
 22.78  1.20     1 │    → callq  rand@plt

The titles are displayed at row 0 of annotate browser if row 0 doesn't
have values of percent, ipc and cycle.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Acked-by: NMilian Wolff <milian.wolff@kdab.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/1493909895-9668-3-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In annotate_browser_write(),

        if (dl->offset != -1 && percent_max != 0.0) {
                if (percent_max != 0.0) {
			...
                }
                ...
        }

The second check of (percent_max != 0.0) is not necessary, remove it.
Signed-off-by: NYao Jin <yao.jin@linux.intel.com>
Acked-by: NMilian Wolff <milian.wolff@kdab.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/1493909895-9668-2-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.

This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.

Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.

One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications.  For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).

Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.

Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.
Original-patch-by: NOleg Nesterov <oleg@redhat.com>
Original-patch-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NHugh Dickins <hughd@google.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull ARM SoC fixes from Olof Johansson:
 "Stream of fixes has slowed down, only a few this week:

   - Some DT fixes for Allwinner platforms, and addition of a clock to
     the R_CCU clock controller that had been missed.

   - A couple of small DT fixes for am335x-sl50"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  arm64: allwinner: a64: Add PLL_PERIPH0 clock to the R_CCU
  ARM: sunxi: h3-h5: Add PLL_PERIPH0 clock to the R_CCU
  ARM: dts: am335x-sl50: Fix cannot claim requested pins for spi0
  ARM: dts: am335x-sl50: Fix card detect pin for mmc1
  arm64: allwinner: h5: Remove syslink to shared DTSI
  ARM: sunxi: h3/h5: fix the compatible of R_CCU

Merge tag 'sunxi-fixes-for-4.12' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux into fixes

Allwinner fixes for 4.12

A few fixes around the PRCM support that got in 4.12 with a wrong
compatible, and a missing clock in the binding.

* tag 'sunxi-fixes-for-4.12' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux:
  arm64: allwinner: a64: Add PLL_PERIPH0 clock to the R_CCU
  ARM: sunxi: h3-h5: Add PLL_PERIPH0 clock to the R_CCU
  arm64: allwinner: h5: Remove syslink to shared DTSI
  ARM: sunxi: h3/h5: fix the compatible of R_CCU
Signed-off-by: NOlof Johansson <olof@lixom.net>

Merge tag 'omap-for-v4.12/fixes-sl50' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Two fixes for am335x-sl50 to fix a boot time error
for claiming SPI pins, and to fix a SDIO card detect
pin for production version of the device.

* tag 'omap-for-v4.12/fixes-sl50' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: dts: am335x-sl50: Fix cannot claim requested pins for spi0
  ARM: dts: am335x-sl50: Fix card detect pin for mmc1
Signed-off-by: NOlof Johansson <olof@lixom.net>

Pull virtio bugfix from Michael Tsirkin:
 "It turns out balloon does not handle IOMMUs correctly. We should fix
  that at some point, for now let's just disable this configuration"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_balloon: disable VIOMMU support

Pull i2c fixes from Wolfram Sang:
 "Two driver bugfixes"

* 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: ismt: fix wrong device address when unmap the data buffer
  i2c: rcar: use correct length when unmapping DMA

Pull MIPS fixes from Ralf Baechle:

 - Three highmem fixes:
    + Fixed mapping initialization
    + Adjust the pkmap location
    + Ensure we use at most one page for PTEs

 - Fix makefile dependencies for .its targets to depend on vmlinux

 - Fix reversed condition in BNEZC and JIALC software branch emulation

 - Only flush initialized flush_insn_slot to avoid NULL pointer
   dereference

 - perf: Remove incorrect odd/even counter handling for I6400

 - ftrace: Fix init functions tracing

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: .its targets depend on vmlinux
  MIPS: Fix bnezc/jialc return address calculation
  MIPS: kprobes: flush_insn_slot should flush only if probe initialised
  MIPS: ftrace: fix init functions tracing
  MIPS: mm: adjust PKMAP location
  MIPS: highmem: ensure that we don't use more than one page for PTEs
  MIPS: mm: fixed mappings: correct initialisation
  MIPS: perf: Remove incorrect odd/even counter handling for I6400

virtio balloon bypasses the DMA API entirely so does not support the
VIOMMU right now.  It's not clear we need that support, for now let's
just make sure we don't pretend to support it.

Cc: stable@vger.kernel.org
Cc: Wei Wang <wei.w.wang@intel.com>
Fixes: 1a937693 ("virtio: new feature to detect IOMMU device quirk")
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NJason Wang <jasowang@redhat.com>

Pull x86 fixes from Thomas Gleixner:
 "Two fixlets for x86:

   - Handle WARN_ONs proper with the new UD based WARN implementation

   - Disable 1G mappings when 2M mappings are disabled by kmemleak or
     debug_pagealloc. Otherwise 1G mappings might still be used,
     confusing the debug mechanisms"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Disable 1GB direct mappings when disabling 2MB mappings
  x86/debug: Handle early WARN_ONs proper

Pull timer fixes from Thomas Gleixner:
 "Three fixlets for timers:

   - Two hot-fixes for the alarmtimer based posix timers, which prevent
     a nasty DOS by self rescheduling timers. The proper cleanup of that
     mess is queued for 4.13

   - Make a function static"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick/broadcast: Make tick_broadcast_setup_oneshot() static
  alarmtimer: Rate limit periodic intervals
  alarmtimer: Prevent overflow of relative timers

Pull scheduler fixes from Thomas Gleixner:
 "Two small fixes for the schedulre core:

   - Use the proper switch_mm() variant in idle_task_exit() because that
     code is not called with interrupts disabled.

   - Fix a confusing typo in a printk"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Idle_task_exit() shouldn't use switch_mm_irqs_off()
  sched/fair: Fix typo in printk message