There's a mistake in dso__adjust_kmod_long_name() that it use strdup()
to dup the new long_name of a dso, but passes the original string to
dso__set_long_name(). Which causes random crash during cleanup.
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Reviewed-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Fixes: c03d5184 ("perf machine: Adjust dso->long_name for offline module")
Link: http://lkml.kernel.org/r/1449455785-42020-1-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now that we have generic MSR trace points we can remove the old
hackish perf MSR read tracing code.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: rostedt@goodmis.org
Link: http://lkml.kernel.org/r/1449018060-1742-4-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

For debugging low level code interacting with the CPU it is often
useful to trace the MSR read/writes. This gives a concise summary of
PMU and other operations.

perf has an ad-hoc way to do this using trace_printk, but it's
somewhat limited (and also now spews ugly boot messages when enabled)

Instead define real trace points for all MSR accesses.

This adds three new trace points: read_msr and write_msr and rdpmc.

They also report if the access faulted (if *_safe is used)

This allows filtering and triggering on specific MSR values, which
allows various more advanced debugging techniques.

All the values are well defined in the CPU documentation.

The trace can be post processed with
Documentation/trace/postprocess/decode_msr.py to add symbolic MSR
names to the trace.

I only added it to native MSR accesses in C, not paravirtualized or in
entry*.S (which is not too interesting)

Originally the patch kit moved the MSRs out of line.  This uses an
alternative approach recommended by Steven Rostedt of only moving the
trace calls out of line, but open coding the access to the jump label.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1449018060-1742-3-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Steven recommended open coding access to tracepoint->key to add
trace points to headers. Unfortunately this is difficult for some
headers (such as x86 asm/msr.h) because including tracepoint.h
includes so many other headers that it causes include loops.
The main problem is the include of linux/rcupdate.h, which
pulls in a lot of other headers. The rcu header is only needed
when actually defining trace points.

Move the struct tracepoint into a separate tracepoint-defs.h
header that can be included without pulling in all of RCU.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1449018060-1742-2-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

asm/atomic.h doesn't really need asm/processor.h anymore. Everything
it uses has moved to other header files. So remove that include.

processor.h is a nasty header that includes lots of
other headers and makes it prone to include loops. Removing the
include here makes asm/atomic.h a "leaf" header that can
be safely included in most other headers.

The only fallout is in the lib/atomic tester which relied on
this implicit include. Give it an explicit include.
(the include is in ifdef because the user is also in ifdef)
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: rostedt@goodmis.org
Link: http://lkml.kernel.org/r/1449018060-1742-1-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Fix a definition in the perf rapl driver. __initconst must
be applied to a const object, but to declare a const pointer
you need to use * const ..., not const ... *

This fixes a section attribute conflict with LTO builds.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1448905722-2767-1-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Various functions implement the same pattern to send IPIs to an
event's CPU. Collapse the easy ones in a common helper function to
reduce duplication.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

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

In case we monitor events system wide, we get EXIT event
(when configured) twice for each task that exited.

Note doubled lines with same pid/tid in following example:

  $ sudo ./perf record -a
  ^C[ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.480 MB perf.data (2518 samples) ]
  $ sudo ./perf report -D | grep EXIT

  0 60290687567581 0x59910 [0x38]: PERF_RECORD_EXIT(1250:1250):(1250:1250)
  0 60290687568354 0x59948 [0x38]: PERF_RECORD_EXIT(1250:1250):(1250:1250)
  0 60290687988744 0x59ad8 [0x38]: PERF_RECORD_EXIT(1250:1250):(1250:1250)
  0 60290687989198 0x59b10 [0x38]: PERF_RECORD_EXIT(1250:1250):(1250:1250)
  1 60290692567895 0x62af0 [0x38]: PERF_RECORD_EXIT(1253:1253):(1253:1253)
  1 60290692568322 0x62b28 [0x38]: PERF_RECORD_EXIT(1253:1253):(1253:1253)
  2 60290692739276 0x69a18 [0x38]: PERF_RECORD_EXIT(1252:1252):(1252:1252)
  2 60290692739910 0x69a50 [0x38]: PERF_RECORD_EXIT(1252:1252):(1252:1252)

The reason is that the cpu contexts are processes each time
we call perf_event_task. I'm changing the perf_event_aux logic
to serve task_ctx and cpu contexts separately, which ensure we
don't get EXIT event generated twice on same cpu context.

This does not affect other auxiliary events, as they don't
use task_ctx at all.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1446649205-5822-1-git-send-email-jolsa@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

We need to add rest of the flags to the constraint mask
instead of another INTEL_ARCH_EVENT_MASK, fixing a typo.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1447061071-28085-1-git-send-email-jolsa@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

There was a mistake in the Haswell constraints table.
Signed-off-by: NYuanfang Chen <cheny@udel.edu>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: NAndi Kleen <ak@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1448384701-9110-1-git-send-email-cheny@udel.eduSigned-off-by: NIngo Molnar <mingo@kernel.org>

Dmitry reported a fairly silly recursive lock deadlock for
PERF_EVENT_IOC_PERIOD, fix this by explicitly doing the inactive part of
__perf_event_period() instead of calling that function.
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: c7999c6f ("perf: Fix PERF_EVENT_IOC_PERIOD migration race")
Link: http://lkml.kernel.org/r/20151130115615.GJ17308@twins.programming.kicks-ass.netSigned-off-by: NIngo Molnar <mingo@kernel.org>

Merge tag 'perf-core-for-mingo' 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 'perf list' segfault due to lack of support for PERF_CONF_SW_BPF_OUTPUT
    in an array used just for printing available events, robustify the code
    involved (Arnaldo Carvalho de Melo)

  - 'perf test unwind' should create kernel maps, now that entry works and the
    test passes (Jiri Olsa)

  - Fix showing the running kernel build id in 'perf buildid-list' (Michael Petlan)

  - Fix command line symbol filtering in 'perf report' (Namhyung Kim)

Infrastructure changes:

  - Extract and collect map info from BPF object files in libbpf (Wang Nan)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Following patches are going to introduce BPF object level configuration
to enable setting values into BPF maps. To avoid confusion, this patch
renames existing 'config' in bpf-loader.c to 'program config'. Following
patches would introduce 'object config'.
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1448614067-197576-4-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This patch collects name of maps in BPF object files and saves them into
'maps' field in 'struct bpf_object'. 'bpf_object__get_map_by_name' is
introduced to retrive fd and definitions of a map through its name.
Signed-off-by: NHe Kuang <hekuang@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1448614067-197576-3-git-send-email-wangnan0@huawei.comSigned-off-by: NWang Nan <wangnan0@huawei.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This patch collects more information from maps sections in BPF object
files into 'struct bpf_object', enables later patches access those
information (such as the type and size of the map).

In this patch, a new handler 'struct bpf_map' is extracted in parallel
with bpf_object and bpf_program. Its iterator and accessor is also
created.
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1448614067-197576-2-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When perf report on TUI was called with -S symbol filter, it should
update nr entries even if min_pcnt is 0.  IIRC the reason was to update
nr entries after applying minimum percent threshold.  But if symbol
filter was given on command line (with -S option), it should use
hists->nr_non_filtered_entries instead of hists->nr_entries.

So this patch fixes a bug of navigating hists browser that the cursor
goes beyond the number of entries when -S (or similar) option is used.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1448645559-31167-3-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

If user gives a filter, perf marks the corresponding column elided and
omits the output.  But it should process and aggregates samples using
the field, otherwise samples will be aggregated as if the column was not
there resulted in incorrect output.

For example, I'd like to set a filter on native_write_msr_safe.  The
original overhead of the function is negligible.

  $ perf report | grep native_write_msr_safe
      0.00%  swapper  [kernel.vmlinux]  native_write_msr_safe
      0.00%  perf     [kernel.vmlinux]  native_write_msr_safe

However adding -S option gives different output.

  $ perf report -S native_write_msr_safe --percentage absolute | \
  > grep -e swapper -e perf
     51.47%  swapper  [kernel.vmlinux]
      4.14%  perf     [kernel.vmlinux]

Since it aggregated samples using comm and dso only.  In fact, the above
values are same when it sorts with -s comm,dso.

  $ perf report -s comm,dso | grep -e swapper -e perf
     51.47%  swapper  [kernel.vmlinux]
      4.14%  perf     [kernel.vmlinux]

This resulted in TUI failure with -ERANGE since it tries to increase
sample hit count for annotation with wrong symbols due to incorrect
aggregation.

This patch fixes it not to skip elided fields when comparing samples in
order to insert them to the hists.

Commiter note:

After the patch, with a different workloads:

  # perf report --show-total-period -S native_write_msr_safe --stdio
  #
  # symbol: native_write_msr_safe
  #
  # Samples: 455  of event 'cycles:pp'
  # Event count (approx.): 134787489
  #
  # Overhead Period Command         Shared Object
  # ........ ...... ............... ................
  #
       0.22% 293081 qemu-system-x86 [vmlinux]
       0.19% 255914 swapper         [vmlinux]
       0.00%   2054 Timer           [vmlinux]
       0.00%   1021 firefox         [vmlinux]
       0.00%      2 perf            [vmlinux]

  # perf report --show-total-period | grep native_write_msr_safe
  Failed to open /tmp/perf-14838.map, continuing without symbols
       0.22% 293081 qemu-system-x86 [vmlinux]  [k] native_write_msr_safe
       0.19% 255914 swapper         [vmlinux]  [k] native_write_msr_safe
       0.00%   2054 Timer           [vmlinux]  [k] native_write_msr_safe
       0.00%   1021 firefox         [vmlinux]  [k] native_write_msr_safe
       0.00%      2 perf            [vmlinux]  [k] native_write_msr_safe
  #
Reported-by: NIngo Molnar <mingo@kernel.org>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1448645559-31167-2-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently when perf fails to process samples for some reason, it doesn't
show any message about the failure.  This is very inconvenient for users
especially on TUI as screen is reset after the failure.
Reported-by: NIngo Molnar <mingo@kernel.org>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1448645559-31167-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When a43eec30 ("bpf: introduce bpf_perf_event_output() helper") added
PERF_COUNT_SW_BPF_OUTPUT we ended up with a new entry in the event_symbols_sw
array that wasn't initialized, thus set to NULL, fix print_symbol_events()
to check for that case so that we don't crash if this happens again.

  (gdb) bt
  #0  __match_glob (ignore_space=false, pat=<optimized out>, str=<optimized out>) at util/string.c:198
  #1  strglobmatch (str=<optimized out>, pat=pat@entry=0x7fffffffe61d "stall") at util/string.c:252
  #2  0x00000000004993a5 in print_symbol_events (type=1, syms=0x872880 <event_symbols_sw+160>, max=11, name_only=false, event_glob=0x7fffffffe61d "stall")
      at util/parse-events.c:1615
  #3  print_events (event_glob=event_glob@entry=0x7fffffffe61d "stall", name_only=false) at util/parse-events.c:1675
  #4  0x000000000042c79e in cmd_list (argc=1, argv=0x7fffffffe390, prefix=<optimized out>) at builtin-list.c:68
  #5  0x00000000004788a5 in run_builtin (p=p@entry=0x871758 <commands+120>, argc=argc@entry=2, argv=argv@entry=0x7fffffffe390) at perf.c:370
  #6  0x0000000000420ab0 in handle_internal_command (argv=0x7fffffffe390, argc=2) at perf.c:429
  #7  run_argv (argv=0x7fffffffe110, argcp=0x7fffffffe11c) at perf.c:473
  #8  main (argc=2, argv=0x7fffffffe390) at perf.c:588
  (gdb) p event_symbols_sw[PERF_COUNT_SW_BPF_OUTPUT]
  $4 = {symbol = 0x0, alias = 0x0}
  (gdb)

A patch to robustify perf to not segfault when the next counter gets added in
the kernel will follow this one.
Reported-by: NIngo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-57wysblcjfrseb0zg5u7ek10@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When PERF_COUNT_SW_BPF_OUTPUT was added to the kernel we should've
added it to tools/perf, where it is used just to list events.

This ended up causing a segfault in commands like "perf list stall".

Fix it by adding that new software counter.

A patch to robustify perf to not segfault when the next counter gets
added in the kernel will follow this one.
Reported-by: NIngo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-uya354upi3eprsey6mi5962d@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The 'perf test unwind' is failing because it forgot to create the kernel
maps, fix it.

After the patch:

  # perf test unwind
  40: Test dwarf unwind         : Ok
Reported-and-Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NJiri Olsa <jolsa@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20151127082121.GA24503@krava.brq.redhat.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The --kernel option of perf buildid-list tool should show the running
kernel buildid.  The functionality has been lost during other changes of
the related code.

The build_id__sprintf() function should return length of the build-id
string,  but it was the length of the build-id raw data instead. Due to
that, some return value checking caused that the final string was not
printed out.

With this patch the build_id__sprintf() returns the correct value, so
the --kernel option works again.

Before:

	# perf buildid-list --kernel
	#

After:

	# perf buildid-list --kernel
	972c1edab5bdc06cc224af45d510af662a3c6972
	#
Signed-off-by: NMichael Petlan <mpetlan@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LPU-Reference: 1448632089.24573.114.camel@redhat.com
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

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

  - Add 'vmlinux.debug' to the vmlinux search path (Ekaterina Tumanova)

  - Do not show sample_(type|period) in the perf_event_attr dump when using
    -v with 'perf stat' (Jiri Olsa)

  - Display the WEIGHT sample bit, when set, in 'perf evlist -v' (Jiri Olsa)

  - Honour --hide-unresolved in 'report', will honour it as well in 'top'
    when --hide-unresolved gets supported in that tool (Namhyung Kim)

  - Fix freeze wit h--call-graph 'flat/folded' due to not properly
    reinitializing the callchain rb_tree (Namhyumg Kim)

  - Set dso->long_name when a module name is passed as a parameter
    to tools like 'perf probe' but the 'struct dso' associated to that module
    still doesn't have the full path for the module, just the '[name]' one
    obtained from /proc/modules (Wang Nan)

  - Fix anon_hugepage mmaps detection using scanf on /proc/PID/smaps (Yannick Brosseau)

Infrastructure changes:

  - Add helper function for updating bpf maps elements (He Kuang)

  - Fix traceevents plugins build race (Jiri Olsa)

  - Add the $OUTPUT path prefix with 'fixdep' (Jiri Olsa)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Add bpf_map_update_elem() helper function which calls the sys_bpf
syscall to update elements in bpf maps. Upcoming patches will use it to
adjust data in map through the perf command line.
Signed-off-by: NHe Kuang <hekuang@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1448372181-151723-4-git-send-email-wangnan0@huawei.comSigned-off-by: NWang Nan <wangnan0@huawei.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Adding WIEGHT bit_name call to display sample_type properly.

  $ perf evlist -v
  cpu/mem-loads/pp: ...SNIP... sample_type: IP|TID|TIME|ADDR|ID|CPU|DATA_SRC|WEIGHT ...
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
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/1448465815-27404-2-git-send-email-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Clear sample_(type|period) for counting, as it only confuses debug
output with unwanted sampling details:

Before:

  $ sudo perf stat -e 'raw_syscalls:sys_enter' -vv ls
  ------------------------------------------------------------
  perf_event_attr:
    type                             2
    size                             112
    config                           0x11
    { sample_period, sample_freq }   1
    sample_type                      TIME|CPU|PERIOD|RAW
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    enable_on_exec                   1
    exclude_guest                    1
  ...

After:
  $ sudo perf stat -e 'raw_syscalls:sys_enter' -vv ls
  ------------------------------------------------------------
  perf_event_attr:
    type                             2
    size                             112
    config                           0x11
    read_format                      TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING
    disabled                         1
    inherit                          1
    enable_on_exec                   1
    exclude_guest                    1
  ...
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
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/1448465815-27404-1-git-send-email-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently when debuginfo is separated to vmlinux.debug, it's contents
get ignored. Let's change that and add it to the vmlinux_path list.
Signed-off-by: NEkaterina Tumanova <tumanova@linux.vnet.ibm.com>
Acked-by: NAlexander Yarygin <yarygin@linux.vnet.ibm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1448469166-61363-3-git-send-email-tumanova@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Refactor vmlinux_path__init() to ease subsequent additions of new
vmlinux locations.
Signed-off-by: NEkaterina Tumanova <tumanova@linux.vnet.ibm.com>
Acked-by: NAlexander Yarygin <yarygin@linux.vnet.ibm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1448469166-61363-2-git-send-email-tumanova@linux.vnet.ibm.com
[ Rename vmlinux_path__update() to vmlinux_path__add() ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Adding OUTPUT path prefix for fixdep target so we use it properly in out
of tree builds.

If the fixdep already existed in the tree, the out of tree build would
see it already exist and did not build the out of tree version, as
reported by Arnaldo:

  [acme@zoo linux]$ make O=/tmp/build/perf -C tools/perf
  make: Entering directory '/home/git/linux/tools/perf'
    BUILD:   Doing 'make -j4' parallel build
  make[2]: Nothing to be done for 'fixdep'.
  make: Leaving directory '/home/git/linux/tools/perf'
Reported-and-Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
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>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20151126185055.GC19410@krava.brq.redhat.com
[ Fixed conflict with 5725dd8f ("tools build: Clean CFLAGS and LDFLAGS for fixdep") ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Passing perf_script struct into process_event function, so we could
process configuration data for event printing.

It will be used in following patch to get event name string width.
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/20151126175521.GA18979@krava.brq.redhat.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When parsing /proc/xxx/maps, the sscanf in perf_event__synthesize_mmap_events
truncate the map name at the space in "/anon_hugepage (deleted)".

is_anon_memory() then only receives the string "/anon_hugepage" and does
not detect it.  We change is_anon_memory() to only compare the first
part of the string, effectively ignoring if " (deleted)" is there.
Signed-off-by: NYannick Brosseau <scientist@fb.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Joshua Zhu <zhu.wen-jie@hp.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/1448538152-2898-1-git-send-email-scientist@fb.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Something unexpected may happen if copy statically linked perf to a
production environment:

  # ./perf probe -m ./mymodule.ko my_func
  [mymodule] with build id 326ab42550ef3d24944f53c817533728367effeb not found, continuing without symbols
  Failed to find symbol my_func in /home/wangnan/kmodule/mymodule.ko
    Error: Failed to add events.
  # ./perf buildid-cache -a ./mymodule.ko
  # ./perf probe -m ./mymodule.ko my_func
  Added new event:
    probe:my_func        (on my_func in /home/wangnan/kmodule/mymodule.ko)

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

  	perf record -e probe:my_func -aR sleep 1

Where:

  # ldd ./perf
 	not a dynamic executable
  # strace -e open ./perf probe -m ./mymodule.ko my_func
  ...
  open("/home/wangnan/kmodule/mymodule.ko", O_RDONLY) = 3
  open("/home/wangnan/kmodule/../lib64/elfutils/libebl_x86_64.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
  ...
  open("/lib64/tls/libebl_x86_64.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
  open("/lib64/libebl_x86_64.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
  open("/usr/lib64/tls/libebl_x86_64.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
  open("/usr/lib64/libebl_x86_64.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
  open("[mymodule]", O_RDONLY)            = -1 ENOENT (No such file or directory)
  open("/home/wangnan/.debug/.build-id/32/6ab42550ef3d24944f53c817533728367effeb", O_RDONLY) = -1 ENOENT (No such file or directory)
  open("[mymodule]", O_RDONLY)            = -1 ENOENT (No such file or directory)

In the above example, probe fails before we put the module into
buildid-cache. However, user would expect it success in both case
because perf is able to find probe points actually.

The reason is because perf won't utilize module's full path if it failed
to open debuginfo. In:

     convert_to_probe_trace_events ->
        find_probe_trace_events_from_map ->
            get_target_map ->
                kernel_get_module_map ->
                    machine__findnew_module_map ->
                        map_groups__find_by_name

map_groups__find_by_name() is able to find the map of that module, but
this information is found from /proc/module before it knows the real
path of the offline module. Therefore, the map->dso->long_name is set to
something like '[mymodule]', which prevent dso__load() find the real
path of the module file.

In another aspect, if dso__load() can get the offline module through
buildid cache, it can read symble table from that ko. Even if debuginfo
is not available, 'perf probe' can success if the '.symtab' can be
found.

This patch improves machine__findnew_module_map(): when dso->long_name
is leading with '[' (doesn't find path of module when parsing
/proc/modules), fixes it by dso__set_long_name(), so following
dso__load() is possible to find the symbol table.

This patch won't interfere with buildid matching. Here is the test
result:

  # ./perf probe -m ./mymodule.ko my_func
  Added new event:
    probe:my_func        (on my_func in /home/wangnan/kmodule/mymodule.ko)

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

  	perf record -e probe:my_func -aR sleep 1

  # ./perf probe -d '*'
  Removed event: probe:my_func
  # mv ./mymodule.{ko,.bak}
  # mv ./moduleb.ko mymodule.ko
  # ./perf probe -m ./mymodule.ko my_func
  /home/wangnan/kmodule/mymodule.ko with build id 326ab42550ef3d24944f53c817533728367effeb not found, continuing without symbols
  Failed to find symbol my_func in /home/wangnan/kmodule/mymodule.ko
    Error: Failed to add events.

  # ./perf probe -v -m ./mymodule.ko my_func
  probe-definition(0): my_func
  symbol:my_func file:(null) line:0 offset:0 return:0 lazy:(null)
  0 arguments
  Could not open debuginfo. Try to use symbols.
  symsrc__init: build id mismatch for /home/wangnan/kmodule/mymodule.ko.
  /home/wangnan/kmodule/mymodule.ko with build id 326ab42550ef3d24944f53c817533728367effeb not found, continuing without symbols
  Failed to find symbol my_func in /home/wangnan/kmodule/mymodule.ko
    Error: Failed to add events. Reason: No such file or directory (Code: -2)
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1448510397-187965-1-git-send-email-wangnan0@huawei.com
[ Renamed adjust_dso_long_name() do dso__adjust_kmod_long_name() ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Ingo reported following build failure:

  $ make clean install
  ...
    CC       plugin_kmem.o
  fixdep: error opening depfile: ./.plugin_hrtimer.o.d: No such file or directory
  /home/mingo/tip/tools/build/Makefile.build:77: recipe for target
  'plugin_hrtimer.o' failed
  make[3]: *** [plugin_hrtimer.o] Error 2
  Makefile:189: recipe for target 'plugin_hrtimer-in.o' failed
  make[2]: *** [plugin_hrtimer-in.o] Error 2
  Makefile.perf:414: recipe for target 'libtraceevent_plugins' failed
  make[1]: *** [libtraceevent_plugins] Error 2
  make[1]: *** Waiting for unfinished jobs....

Currently we have the install-traceevent-plugins target being dependent
on $(LIBTRACEEVENT), which will actualy not build any plugin. So the
install-traceevent-plugins target itself will try to build plugins,
but..

Plugins built is also triggered by perf build itself via
libtraceevent_plugins target.

This might cause a race having one make thread removing temp files from
another and result in above error. Fixing this by having proper plugins
build dependency before installing plugins.
Reported-and-Tested-by: N: Ingo Molnar <mingo@kernel.org>
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/1448546044-28973-3-git-send-email-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The default script handler (the one that displays samples on screen) is
implemented scripting_ops instance with process_event callback.

This way we can't pass any script config into display function, because
we don't want perl or python handlers to be depended on perf script
internals.

Removing the default_scripting_ops and calling process event function
directly. This way it's possible to pass perf_script struct and process
configuration data in following commit.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1448546125-29245-1-git-send-email-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The callchain rbtree is rebuilt periodically, so it needs to
reinitialize the root everytime.  Otherwise it can be stuck in the
rbtree insertion with stale pointers.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1448521700-32062-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

If user requested to hide unresolved entries, skip unresolved callchains
as well as hist entries.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1448521700-32062-3-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-core-for-mingo-2' 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 to free temporal Dwarf_Frame correctly in 'perf probe', fixing a
    regression introduced in perf/core that prevented, at least, adding
    an uprobe collecting function parameter values (Masami Hiramatsu)

  - Fix output of %llu for 64 bit values read on 32 bit machines in
    libtraceevent (Steven Rostedt)

Developer visible:

  - Clean CFLAGS and LDFLAGS for fixdep in tools/build (Wang Nan)

  - Don't do a feature check when cleaning tools/lib/bpf (Wang Nan)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Before this patch libbpf always do feature check even when cleaning.

For example:

  $ cd kernel/tools/lib/bpf
  $ make

  Auto-detecting system features:
  ...                        libelf: [ on  ]
  ...                           bpf: [ on  ]

    CC       libbpf.o
    CC       bpf.o
    LD       libbpf-in.o
    LINK     libbpf.a
    LINK     libbpf.so
  $ make clean
    CLEAN    libbpf
    CLEAN    core-gen
  $ make clean

  Auto-detecting system features:
  ...                        libelf: [ on  ]
  ...                           bpf: [ on  ]

    CLEAN    libbpf
    CLEAN    core-gen
  $

Although the first 'make clean' doesn't show feature check result, it
still does the check. No output because check result is similar to
FEATURE-DUMP.libbpf.

This patch uses same method as perf to turn off feature checking when
'make clean'.
Reported-and-Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1448372181-151723-3-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Sometimes passing variables to tools/build is dangerous. For example, on
my platform there is a gcc problem (gcc 4.8.1):

It passes the stackprotector-all feature check:

  $ gcc -fstack-protector-all -c ./test.c
  $ echo $?
  0

But requires LDFLAGS support if separate compiling and linking:
  $ gcc -fstack-protector-all -c ./test.c
  $ gcc ./test.o
  ./test.o: In function `main':
  test.c:(.text+0xb): undefined reference to `__stack_chk_guard'
  test.c:(.text+0x21): undefined reference to `__stack_chk_guard'
  collect2: error: ld returned 1 exit status
  $ gcc -fstack-protector-all ./test.o
  $ echo $?
  0
  $ gcc ./test.o -lssp
  $ echo $?
  0
  $

In this environment building perf throws an error:

  $ make
    BUILD:   Doing 'make -j24' parallel build
  config/Makefile:344: No libunwind found. Please install libunwind-dev[el] >= 1.1 and/or set LIBUNWIND_DIR
  config/Makefile:403: No libaudit.h found, disables 'trace' tool, please install audit-libs-devel or libaudit-dev
  config/Makefile:418: slang not found, disables TUI support. Please install slang-devel or libslang-dev
  config/Makefile:432: GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev
  config/Makefile:564: No bfd.h/libbfd found, please install binutils-dev[el]/zlib-static/libiberty-dev to gain symbol demangling
  config/Makefile:606: No numa.h found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev
    CC       fixdep.o
    LD       fixdep-in.o
    LINK     fixdep
  fixdep-in.o: In function `parse_dep_file':
  /kernel/tools/build/fixdep.c:47: undefined reference to `__stack_chk_guard'
  /kernel/tools/build/fixdep.c:117: undefined reference to `__stack_chk_guard'
  fixdep-in.o: In function `main':
  /kernel-hydrogen/tools/build/fixdep.c:156: undefined reference to `__stack_chk_guard'
  /kernel/tools/build/fixdep.c:168: undefined reference to `__stack_chk_guard'
  collect2: error: ld returned 1 exit status
  make[2]: *** [fixdep] Error 1
  make[1]: *** [fixdep] Error 2
  make: *** [all] Error 2

This is because the CFLAGS used in building perf pollutes the CFLAGS
used for fixdep, passing -fstack-protector-all to buiold fixdep which is
obviously not required. Since fixdep is a small host side tool, we
should keep its CFLAGS/LDFLAGS simple and clean.

This patch clears the CFLAGS and LDFLAGS passed when building fixdep, so
such gcc problem won't block the perf build process.
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1448372181-151723-2-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>