Commit Graph

547846 Commits

Author SHA1 Message Date
Wang Nan
07bc5c699a perf tools: Make fetch_kernel_version() publicly available
There are 2 places in llvm-utils.c which find kernel version information
through uname. This patch extracts the uname related code into a
fetch_kernel_version() function and puts it into util.h so it can be
reused.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446818135-87310-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06 15:57:18 -03:00
Wang Nan
45825d8ab8 bpf tools: Add new API bpf_object__get_kversion()
bpf_object__get_kversion() can be used to fetch value of object's
'version' section. Following patch will use it for error reporting.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446817783-86722-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06 15:56:41 -03:00
Wang Nan
6371ca3b54 bpf tools: Improve libbpf error reporting
In this patch, a series of libbpf specific error numbers and
libbpf_strerror() are introduced to help reporting errors.

Functions are updated to pass correct the error number through the
CHECK_ERR() macro.

All users of bpf_object__open{_buffer}() and bpf_program__title() in
perf are modified accordingly. In addition, due to the error codes
changing, bpf__strerror_load() is also modified to use them.

bpf__strerror_head() is also changed accordingly so it can parse libbpf
errors. bpf_loader_strerror() is introduced for that purpose, and will
be improved by the following patch.

load_program() is improved not to dump log buffer if it is empty. log
buffer is also used to deduce whether the error was caused by an invalid
program or other problem.

v1 -> v2:

 - Using macro for error code.

 - Fetch error message based on array index, eliminate for-loop.

 - Use log buffer to detect the reason of failure. 3 new error code
   are introduced to replace LIBBPF_ERRNO__LOAD.

In v1:

  # perf record -e ./test_ill_program.o ls
  event syntax error: './test_ill_program.o'
                       \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object
  SKIP

  # perf record -e ./test_kversion_nomatch_program.o ls
  event syntax error: './test_kversion_nomatch_program.o'
                       \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object
  SKIP

  # perf record -e ./test_big_program.o ls
  event syntax error: './test_big_program.o'
                       \___ Failed to load program: Validate your program and check 'license'/'version' sections in your object
  SKIP

  In v2:

  # perf record -e ./test_ill_program.o ls
  event syntax error: './test_ill_program.o'
                       \___ Kernel verifier blocks program loading
  SKIP

  # perf record -e ./test_kversion_nomatch_program.o
  event syntax error: './test_kversion_nomatch_program.o'
                       \___ Incorrect kernel version
  SKIP
  (Will be further improved by following patches)

  # perf record -e ./test_big_program.o
  event syntax error: './test_big_program.o'
                       \___ Program too big
  SKIP

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446817783-86722-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06 15:52:41 -03:00
Masami Hiramatsu
0a62f6869f perf probe: Cleanup find_perf_probe_point_from_map to reduce redundancy
In find_perf_probe_point_from_map(), the 'ret' variable is initialized
with -ENOENT but overwritten by the return code of
kernel_get_symbol_address_by_name(), and after that it is re-initialized
with -ENOENT again.

Setting ret=-ENOENT twice looks a bit redundant. This avoids the
overwriting and just returns -ENOENT if some error happens to simplify
the code.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/n/tip-ufp1zgbktzmttcputozneomd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06 10:47:33 -03:00
Andi Kleen
62ec9b3f02 perf annotate: Inform the user about objdump failures in --stdio
When the browser fails to annotate it is difficult for users to find out
what went wrong.

Add some errors for objdump failures that are displayed in the UI.

Note it would be even better to handle these errors smarter, like
falling back to the binary when the debug info is somehow corrupted. But
for now just giving a better error is an improvement.

Committer note:

This works for --stdio, where errors just scroll by the screen:

  # perf annotate --stdio intel_idle
  Failure running objdump  --start-address=0xffffffff81418290 --stop-address=0xffffffff814183ae -l -d --no-show-raw -S -C /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1 2>/dev/null|grep -v /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1|expand
   Percent |      Source code & Disassembly of vmlinux for cycles:pp
  ------------------------------------------------------------------

And with that one can use that command line to try to find out more about what
happened instead of getting a blank screen, an improvement.

We need tho to improve this further to get it to work with other UIs, like
--tui and --gtk, where it continues showing a blank screen, no messages, as
the pr_err() used is enough just for --stdio.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1446779167-18949-1-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06 10:20:48 -03:00
Jiri Olsa
e054731113 perf stat: Make stat options global
So they can be used in perf stat record command in following patch.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Kan Liang <kan.liang@intel.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/1446734469-11352-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 17:54:34 -03:00
Jiri Olsa
0014de172d perf sched latency: Fix thread pid reuse issue
The latency subcommand holds a tree of working atoms sorted by thread's
pid/tid. If there's new thread with same pid and tid, the old working atom is
found and assert bug condition is hit in search function:

  thread_atoms_search: Assertion `!(thread != atoms->thread)' failed

Changing the sort function to use thread object pointers together with pid and
tid check. This way new thread will never find old one with same pid/tid.

Link: http://lkml.kernel.org/n/tip-o4doazhhv0zax5zshkg8hnys@git.kernel.org
Reported-by: Mohit Agrawal <moagrawa@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1446462625-15807-1-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 12:51:00 -03:00
Wang Nan
98d3b258ed perf tools: Fix find_perf_probe_point_from_map() which incorrectly returns success
It is possible that find_perf_probe_point_from_map() fails to find a
symbol but still returns 0 because of an small error when coding:
find_perf_probe_point_from_map() set 'ret' to error code at first, but
also use it to hold return value of kernel_get_symbol_address_by_name().

This patch resets 'ret' to error even kernel_get_symbol_address_by_name()
success, so if !sym, the whole function returns error correctly.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@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/1446729565-27592-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 12:47:52 -03:00
Peter Feiner
956959f6b7 perf trace: Fix documentation for -i
The -i flag was incorrectly listed as a short flag for --no-inherit.  It
should have only been listed as a short flag for --input.

This documentation error has existed since the --input flag was
introduced in 6810fc915f (perf trace: Add
option to analyze events in a file versus live).

Signed-off-by: Peter Feiner <pfeiner@google.com>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1446657706-14518-1-git-send-email-pfeiner@google.com
Fixes: 6810fc915f ("perf trace: Add option to analyze events in a file versus live")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 12:47:51 -03:00
Yunlong Song
0c77c04aa9 tools lib bpf: Change FEATURE-DUMP to FEATURE-DUMP.libbpf
Commit ed63f34c02 ("perf tools: Make perf
depend on libbpf") triggers the build of libbpf when building the perf
tools, dynamically creating FEATURE-DUMP.libbpf.

It failed to update the tools/lib/bpf/.gitignore file to have that
prefix, fix it.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 65f041bee7 ("tools lib bpf: Use FEATURE_USER to allow building in the same dir as perf")
Link: http://lkml.kernel.org/r/1446706594-4142-1-git-send-email-yunlong.song@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 12:47:51 -03:00
Wang Nan
4a4f66a1a7 perf llvm: Pass LINUX_VERSION_CODE to BPF program when compiling
Arnaldo suggests to make LINUX_VERSION_CODE works like __func__ and
__FILE__ so user don't need to care setting right linux version too
much. In this patch, perf llvm transfers LINUX_VERSION_CODE macro
through clang cmdline.

[1] http://lkml.kernel.org/r/20151029223744.GK2923@kernel.org

Committer notes:

Before, forgetting to update the version:

  # uname -r
  4.3.0-rc1+
  # cat bpf.c
  __attribute__((section("fork=_do_fork"), used))
  int fork(void *ctx)
  {
          return 1;
  }

  char _license[] __attribute__((section("license"), used)) = "GPL";
  int _version __attribute__((section("version"), used)) = 0x40200;
  #
  # perf record -e bpf.c sleep 1
  event syntax error: 'bpf.c'
                       \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel?

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events
 #

After:

  # grep version bpf.c
  int _version __attribute__((section("version"), used)) = LINUX_VERSION_CODE;
  # perf record -e bpf.c sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.017 MB perf.data ]
  # perf evlist -v
  perf_bpf_probe:fork: type: 2, size: 112, config: 0x5ee, { sample_period,
  sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1,
  inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, task: 1, sample_id_all:
  1, exclude_guest: 1, mmap2: 1, comm_exec: 1
  #

Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446636007-239722-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 12:47:50 -03:00
Wang Nan
59f41af980 perf llvm: Pass number of configured CPUs to clang compiler
This patch introduces a new macro "__NR_CPUS__" to perf's embedded clang
compiler, which represent the number of configured CPUs in this system.
BPF programs can use this macro to create a map with the same number of
system CPUs. For example:

 struct bpf_map_def SEC("maps") pmu_map = {
     .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
     .key_size = sizeof(int),
     .value_size = sizeof(u32),
     .max_entries = __NR_CPUS__,
 };

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446636007-239722-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 12:47:02 -03:00
Arnaldo Carvalho de Melo
98916392a0 perf tools: Allow shuffling the build tests
Those tests take a long time and sometimes we stop it, so allow randomly
shuffling the tests so that we have a better chance of running more of
them in partial 'make build-test' runs.

Using it just on the 'build-test' target, i.e.:

   make -C tools/perf build-test

Is equivalent to:

   make SHUF=1 -C tools/perf -f tests/make

Cc: Adrian Hunter <adrian.hunter@intel.com>
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-ey7461i9q4k8u0987j8guun6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 11:39:54 -03:00
Jiri Olsa
cb8382e058 perf tools: Insert split maps correctly into origin group
When new maps are cloned out of split map they are added into origin
map's group, but their groups pointer is not updated.

This could lead to a segfault, because map->groups is expected to be
always set as reported by Markus:

  __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238
  238             return __machine__kernel_map(map->groups->machine, map->type) =
  (gdb) bt
  #0  __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238
  #1  0x00000000004393e4 in symbol_filter (map=map@entry=0x1abb7a0, sym=sym@entry
  #2  0x00000000004fcd4d in dso__load_sym (dso=dso@entry=0x166dae0, map=map@entry
  #3  0x00000000004a64e0 in dso__load (dso=0x166dae0, map=map@entry=0x1abb7a0, fi
  #4  0x00000000004b941f in map__load (filter=0x4393c0 <symbol_filter>, map=<opti
  #5  map__find_symbol (map=0x1abb7a0, addr=40188, filter=0x4393c0 <symbol_filter
  ...

Adding __map_groups__insert function to add map into groups together
with map->groups pointer update. It takes no lock as opposed to existing
map_groups__insert, as maps__fixup_overlappings(), where it is being
called, already has the necessary lock held.

Using __map_groups__insert to add new maps after map split.

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20151104140811.GA32664@krava.brq.redhat.com
Fixes: cfc5acd4c8 ("perf top: Filter symbols based on __map__is_kernel(map)")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 11:39:38 -03:00
Andi Kleen
eedfcb4bc5 perf stat: Use common printout function to avoid duplicated code
Instead of every caller deciding whether to call abs or nsec printout
do it all in a single central function. No functional changes.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1446515428-7450-3-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-04 15:12:04 -03:00
Andi Kleen
4579ecc8b3 perf stat: Move sw clock metrics printout to stat-shadow
The sw clock metrics printing was missed in the earlier move to
stat-shadow of all the other metric printouts. Move it too.

v2: Fix metrics printing in this version to make bisect safe.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1446515428-7450-2-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-04 15:11:41 -03:00
Namhyung Kim
715f8db910 tools lib bpf: Fix compiler warning on CentOS 6
CC       libbpf.o
  cc1: warnings being treated as errors
  libbpf.c: In function 'bpf_program__title':
  libbpf.c:1037: error: declaration of 'dup' shadows a global declaration
  /usr/include/unistd.h:528: error: shadowed declaration is here
  mv: cannot stat `./.libbpf.o.tmp': No such file or directory
  make[3]: *** [libbpf.o] Error 1
  make[2]: *** [libbpf-in.o] Error 2
  make[1]: *** [/linux/tools/lib/bpf/libbpf.a] Error 2
  make[1]: *** Waiting for unfinished jobs....

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1446549665-2342-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-03 12:13:31 -03:00
Wang Nan
7a0119468c perf bpf: Mute libbpf when '-v' not set
According to [1], libbpf should be muted. This patch reset info and
warning message level to ensure libbpf doesn't output anything even
if error happened.

[1] http://lkml.kernel.org/r/20151020151255.GF5119@kernel.org

Committer note:

Before:

Testing it with an incompatible kernel version in the .c file that
generated foo.o:

  [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
  libbpf: load bpf program failed: Invalid argument
  libbpf: -- BEGIN DUMP LOG ---
  libbpf:

  libbpf: -- END LOG --
  libbpf: failed to load program 'fork=_do_fork'
  libbpf: failed to load object '/tmp/foo.o'
  event syntax error: '/tmp/foo.o'
                       \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel?

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events
  [root@zoo ~]#

After:

  [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
  event syntax error: '/tmp/foo.o'
                       \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel?

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events
  [root@zoo ~]#

This, BTW, need fixing to emit a proper message by validating the
version in the foo.o "version" ELF section against the running kernel,
warning the user instead of asking the kernel to load a binary that it
will refuse due to unmatching kernel version.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446547486-229499-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-03 12:06:04 -03:00
Wang Nan
597bdeb4ab perf test: Keep test result clean if '-v' not set
According to [1], 'perf test' should avoid output too much information
if '-v' is not set, only 'Ok', 'FAIL' or 'Skip' need to be printed.

This patch removes several messages sent directly to stderr to make
the output clean.

Before this patch:

  # perf test dummy
  23: Test using a dummy software event to keep tracking       : (not supported) Ok

After this patch:

  # perf test dummy
  23: Test using a dummy software event to keep tracking       : Skip

[1] http://lkml.kernel.org/r/20151020134155.GE4400@redhat.com

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446547486-229499-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-03 11:45:40 -03:00
Ingo Molnar
bebd23a2ed perf/core improvements and fixes:
New features:
 
 - Allow passing C language eBPF scriptlets via --event in all tools,
   so that it gets built using clang and then pass it to the kernel via
   sys_bpf() (Wang Nan)
 
 - Wire up the loaded ebpf object file with associated kprobes, so that
   it can determine if the kprobes will be filtered or not (Wang Nan)
 
 User visible:
 
 - Add cmd string table to decode sys_bpf first arg in 'trace' (Arnaldo Carvalho de Melo)
 
 - Enable printing of branch stack in 'perf script' (Stephane Eranian)
 
 - Pass the right file with debug info to libunwind (Rabin Vincent)
 
 Build Fixes:
 
 - Make sure fixdep is built before libbpf, fixing a race (Jiri Olsa)
 
 - Fix libiberty feature detection (Rabin Vincent)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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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:

New features:

  - Allow passing C language eBPF scriptlets via --event in all tools,
    so that it gets built using clang and then pass it to the kernel via
    sys_bpf(). (Wang Nan)

  - Wire up the loaded ebpf object file with associated kprobes, so that
    it can determine if the kprobes will be filtered or not. (Wang Nan)

User visible changes:

  - Add cmd string table to decode sys_bpf first arg in 'trace'. (Arnaldo Carvalho de Melo)

  - Enable printing of branch stack in 'perf script'. (Stephane Eranian)

  - Pass the right file with debug info to libunwind. (Rabin Vincent)

Build Fixes:

  - Make sure fixdep is built before libbpf, fixing a race. (Jiri Olsa)

  - Fix libiberty feature detection. (Rabin Vincent)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-30 10:09:37 +01:00
Rabin Vincent
7ed4915ad6 perf unwind: Pass symbol source to libunwind
Even if --symfs is used to point to the debug binaries, we send in the
non-debug filenames to libunwind, which leads to libunwind not finding
the debug frame.  Fix this by preferring the file in --symfs, if it is
available.

Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rabin Vincent <rabinv@axis.com>
Link: http://lkml.kernel.org/r/1446104978-26429-1-git-send-email-rabin.vincent@axis.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-29 17:48:38 -03:00
Rabin Vincent
3af6ed84eb tools build: Fix libiberty feature detection
Any CFLAGS or LDFLAGS set by the user need to be passed to the feature
build command.  This many include for example -I or -L to point to
libraries and include files in custom paths.

In most of the test-*.bin rules in build/feature/Makefile, we use the BUILD
macro which always sends in CFLAGS and LDFLAGS.  The libiberty build line
however doesn't use the BUILD macro and thus needs to send in CFLAGS and
LDFLAGS explicitly.  Without this, when using custom CFLAGS/LDFLAGS, libiberty
fails to be detected and the perf link fails with something like:

   LINK     perf
  libbfd.a(bfd.o): In function `bfd_errmsg':
  bfd.c:(.text+0x168): undefined reference to `xstrerror'
  bbfd.a(opncls.o): In function `_bfd_new_bfd':
  opncls.c:(.text+0xe8): undefined reference to `objalloc_create'
  ...

Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rabin Vincent <rabinv@axis.com>
Link: http://lkml.kernel.org/r/1446104978-26429-2-git-send-email-rabin.vincent@axis.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-29 17:46:35 -03:00
Wang Nan
d509db0473 perf tools: Compile scriptlets to BPF objects when passing '.c' to --event
This patch provides infrastructure for passing source files to --event
directly using:

 # perf record --event bpf-file.c command

This patch does following works:

 1) Allow passing '.c' file to '--event'. parse_events_load_bpf() is
    expanded to allow caller tell it whether the passed file is source
    file or object.

 2) llvm__compile_bpf() is called to compile the '.c' file, the result
    is saved into memory. Use bpf_object__open_buffer() to load the
    in-memory object.

Introduces a bpf-script-example.c so we can manually test it:

 # perf record --clang-opt "-DLINUX_VERSION_CODE=0x40200" --event ./bpf-script-example.c sleep 1

Note that '--clang-opt' must put before '--event'.

Futher patches will merge it into a testcase so can be tested automatically.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-10-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-29 17:16:23 -03:00
Wang Nan
71dc232625 perf record: Add clang options for compiling BPF scripts
Although previous patch allows setting BPF compiler related options in
perfconfig, on some ad-hoc situation it still requires passing options
through cmdline. This patch introduces 2 options to 'perf record' for
this propose: --clang-path and --clang-opt.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-9-git-send-email-wangnan0@huawei.com
[ Add the new options to the 'record' man page ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-29 17:16:22 -03:00
Wang Nan
1f45b1d490 perf bpf: Attach eBPF filter to perf event
This is the final patch which makes basic BPF filter work. After
applying this patch, users are allowed to use BPF filter like:

 # perf record --event ./hello_world.o ls

A bpf_fd field is appended to 'struct evsel', and setup during the
callback function add_bpf_event() for each 'probe_trace_event'.

PERF_EVENT_IOC_SET_BPF ioctl is used to attach eBPF program to a newly
created perf event. The file descriptor of the eBPF program is passed to
perf record using previous patches, and stored into evsel->bpf_fd.

It is possible that different perf event are created for one kprobe
events for different CPUs. In this case, when trying to call the ioctl,
EEXIST will be return. This patch doesn't treat it as an error.

Committer note:

The bpf proggie used so far:

  __attribute__((section("fork=_do_fork"), used))
  int fork(void *ctx)
  {
	  return 0;
  }

  char _license[] __attribute__((section("license"), used)) = "GPL";
  int _version __attribute__((section("version"), used)) = 0x40300;

failed to produce any samples, even with forks happening and it being
running in system wide mode.

That is because now the filter is being associated, and the code above
always returns zero, meaning that all forks will be probed but filtered
away ;-/

Change it to 'return 1;' instead and after that:

  # trace --no-syscalls --event /tmp/foo.o
     0.000 perf_bpf_probe:fork:(ffffffff8109be30))
     2.333 perf_bpf_probe:fork:(ffffffff8109be30))
     3.725 perf_bpf_probe:fork:(ffffffff8109be30))
     4.550 perf_bpf_probe:fork:(ffffffff8109be30))
  ^C#

And it works with all tools, including 'perf trace'.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-8-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-29 17:16:22 -03:00
Jiri Olsa
50f1e6d043 perf tools: Make sure fixdep is built before libbpf
While doing 'make -C tools/perf build-test':

   LD       fixdep-in.o
   LINK     fixdep
 /bin/sh: /home/acme/git/linux/tools/build/fixdep: Permission denied
 make[6]: *** [bpf.o] Error 1
 make[5]: *** [libbpf-in.o] Error 2
 make[4]: *** [/home/acme/git/linux/tools/lib/bpf/libbpf.a] Error 2
 make[4]: *** Waiting for unfinished jobs....

The fixdep tool needs to be built as the first binary.  Libraries are
built in paralel, so each of them needs to depend on fixdep target.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20151028204450.GA25553@krava.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-29 17:16:21 -03:00
Stephane Eranian
dc323ce8e7 perf script: Enable printing of branch stack
This patch improves perf script by enabling printing of the
branch stack via the 'brstack' and 'brstacksym' arguments to
the field selection option -F. The option is off by default
and operates only if the perf.data file has branch stack content.

The branches are printed in to/from pairs. The most recent branch
is printed first. The number of branch entries vary based on the
underlying hardware and filtering used.

The brstack prints FROM/TO addresses in raw hexadecimal format.
The brstacksym prints FROM/TO addresses in symbolic form wherever
possible.

 $ perf script -F ip,brstack
  5d3000 0x401aa0/0x5d2000/M/-/-/-/0 ...

 $ perf script -F ip,brstacksym
  4011e0 noploop+0x0/noploop+0x0/P/-/-/0

The notation F/T/M/X/A/C describes the attributes of the branch.
F=from, T=to, M/P=misprediction/prediction, X=TSX, A=TSX abort, C=cycles (SKL)

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yuanfang Chen <cyfmxc@gmail.com>
Link: http://lkml.kernel.org/r/1441039273-16260-5-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-29 17:16:20 -03:00
Arnaldo Carvalho de Melo
729a78417a perf trace: Add cmd string table to decode sys_bpf first arg
# perf trace -e bpf perf record -e /tmp/foo.o -a
   362.779 (0.130 ms): perf/3451 bpf(cmd: PROG_LOAD, uattr: 0x7ffe9a6825d0, size: 48) = 3

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
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-2b0nknu53baz9e0wj4thcdd8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-29 11:48:18 -03:00
Ingo Molnar
66a565c203 perf/ebpf basic integration
Please see the changeset comments, but this is the very basic integration of
 perf with libbpf that, given a .o file built for the 'bpf' target with clang,
 will get it validated and loaded into the kernel via the sys_bpf syscall, which
 can be seen using 'perf trace' to trace the whole thing looking just for the
 bpf and perf_event_open syscalls:
 
   # perf trace -e bpf,perf_event_open perf record -g --event /tmp/foo.o -a
    362.779 ( 0.129 ms): perf/22408 bpf(cmd: 5, uattr: 0x7ffd4edb6db0, size: 48                           ) = 3
    384.192 ( 0.016 ms): perf/22408 perf_event_open(attr_uptr: 0x7ffd4edbace0, pid: -1, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 5
    384.247 ( 0.038 ms): perf/22408 perf_event_open(attr_uptr: 0x37aedd8, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 5
    384.261 ( 0.007 ms): perf/22408 perf_event_open(attr_uptr: 0x37aedd8, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 5
    387.680 ( 3.413 ms): perf/22408 perf_event_open(attr_uptr: 0x3222f08, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 5
    387.688 ( 0.005 ms): perf/22408 perf_event_open(attr_uptr: 0x3222f08, pid: -1, cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 6
    387.693 ( 0.004 ms): perf/22408 perf_event_open(attr_uptr: 0x3222f08, pid: -1, cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 7
    387.698 ( 0.003 ms): perf/22408 perf_event_open(attr_uptr: 0x3222f08, pid: -1, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 8
   ^C[ perf record: Woken up 1 times to write data ]
     [ perf record: Captured and wrote 0.221 MB perf.data (2 samples) ]
   # perf script
   bash 18389 [002] 83446.412607: perf_bpf_probe:fork: (ffffffff8109be30)
                   29be31 _do_fork (/lib/modules/4.3.0-rc6+/build/vmlinux)
                   96d662 tracesys_phase2 (/lib/modules/4.3.0-rc6+/build/vmlinux)
                    bd56c __libc_fork (/usr/lib64/libc-2.17.so)
                    413b2 make_child (/usr/bin/bash)
 
   bash 18389 [002] 83447.227255: perf_bpf_probe:fork: (ffffffff8109be30)
                   29be31 _do_fork (/lib/modules/4.3.0-rc6+/build/vmlinux)
                   96d662 tracesys_phase2 (/lib/modules/4.3.0-rc6+/build/vmlinux)
                    bd56c __libc_fork (/usr/lib64/libc-2.17.so)
                    413b2 make_child (/usr/bin/bash)
 
   # perf evlist -v
   perf_bpf_probe:fork: type: 2, size: 112, config: 0x6cf, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CALLCHAIN|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
   #
 
 More work is about to be reviewed, tested and merged that will allow the whole
 process of going from a .c file to an .o file via clang, etc to be done
 automagically. (Wang Nan)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-ebpf-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull basic perf/ebpf integration:

 "Please see the changeset comments, but this is the very basic integration of
  perf with libbpf that, given a .o file built for the 'bpf' target with clang,
  will get it validated and loaded into the kernel via the sys_bpf syscall, which
  can be seen using 'perf trace' to trace the whole thing looking just for the
  bpf and perf_event_open syscalls:

    # perf trace -e bpf,perf_event_open perf record -g --event /tmp/foo.o -a
     362.779 ( 0.129 ms): perf/22408 bpf(cmd: 5, uattr: 0x7ffd4edb6db0, size: 48                           ) = 3
     384.192 ( 0.016 ms): perf/22408 perf_event_open(attr_uptr: 0x7ffd4edbace0, pid: -1, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 5
     384.247 ( 0.038 ms): perf/22408 perf_event_open(attr_uptr: 0x37aedd8, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 5
     384.261 ( 0.007 ms): perf/22408 perf_event_open(attr_uptr: 0x37aedd8, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 5
     387.680 ( 3.413 ms): perf/22408 perf_event_open(attr_uptr: 0x3222f08, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 5
     387.688 ( 0.005 ms): perf/22408 perf_event_open(attr_uptr: 0x3222f08, pid: -1, cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 6
     387.693 ( 0.004 ms): perf/22408 perf_event_open(attr_uptr: 0x3222f08, pid: -1, cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 7
     387.698 ( 0.003 ms): perf/22408 perf_event_open(attr_uptr: 0x3222f08, pid: -1, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 8
    ^C[ perf record: Woken up 1 times to write data ]
      [ perf record: Captured and wrote 0.221 MB perf.data (2 samples) ]
    # perf script
    bash 18389 [002] 83446.412607: perf_bpf_probe:fork: (ffffffff8109be30)
                    29be31 _do_fork (/lib/modules/4.3.0-rc6+/build/vmlinux)
                    96d662 tracesys_phase2 (/lib/modules/4.3.0-rc6+/build/vmlinux)
                     bd56c __libc_fork (/usr/lib64/libc-2.17.so)
                     413b2 make_child (/usr/bin/bash)

    bash 18389 [002] 83447.227255: perf_bpf_probe:fork: (ffffffff8109be30)
                    29be31 _do_fork (/lib/modules/4.3.0-rc6+/build/vmlinux)
                    96d662 tracesys_phase2 (/lib/modules/4.3.0-rc6+/build/vmlinux)
                     bd56c __libc_fork (/usr/lib64/libc-2.17.so)
                     413b2 make_child (/usr/bin/bash)

    # perf evlist -v
    perf_bpf_probe:fork: type: 2, size: 112, config: 0x6cf, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CALLCHAIN|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
    #

  More work is about to be reviewed, tested and merged that will allow the whole
  process of going from a .c file to an .o file via clang, etc to be done
  automagically. (Wang Nan)"

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-29 13:17:56 +01:00
Ingo Molnar
6fc774ef4c perf/core improvements and fixes:
User visible:
 
 - Enable per-event perf_event_attr.inherit setting by config terms, i.e.
   this becomes possible:
 
       $ perf record -e cycles/inherit/ -e instructions/no-inherit/
 
   This affects the default, that can be changed globally using the --no-inherit
   option.
 
   This fine grained control appeared in the eBPF patchkit, but this added
   flexibility may end up being useful in other scenarios (Wang Nan)
 
 - Setup pager when printing usage and help, we have long lists of options,
   better use the pager like we do with normal tooling output, i.e. when needed,
   and including any error messages in the paged output (Namhyung Kim)
 
 - Search for more options when passing args to -h, e.g.: (Arnaldo Carvalho de Melo)
 
   $ perf report -h interface
 
    Usage: perf report [<options>]
 
     --gtk    Use the GTK2 interface
     --stdio  Use the stdio interface
     --tui    Use the TUI interface
 
 - Fix reading separate debuginfo files based on a build-id, problem
   found on a Debian system (Dima Kogan)
 
 - Fix endless loop when splitting kallsyms symbols per section for
   handling kcore files, problem found on a s390x system (Jiri Olsa)
 
 Infrastructure:
 
 - Prep work for the 'perf stat record' work that will allow generating
   perf.data files with counting data in addition to the sampling mode
   we have now (Jiri Olsa)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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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:

  - Enable per-event perf_event_attr.inherit setting by config terms, i.e.
    this becomes possible:

        $ perf record -e cycles/inherit/ -e instructions/no-inherit/

    This affects the default, that can be changed globally using the --no-inherit
    option.

    This fine grained control appeared in the eBPF patchkit, but this added
    flexibility may end up being useful in other scenarios. (Wang Nan)

  - Setup pager when printing usage and help, we have long lists of options,
    better use the pager like we do with normal tooling output, i.e. when needed,
    and including any error messages in the paged output. (Namhyung Kim)

  - Search for more options when passing args to -h, e.g.: (Arnaldo Carvalho de Melo)

    $ perf report -h interface

     Usage: perf report [<options>]

      --gtk    Use the GTK2 interface
      --stdio  Use the stdio interface
      --tui    Use the TUI interface

  - Fix reading separate debuginfo files based on a build-id, problem
    found on a Debian system. (Dima Kogan)

  - Fix endless loop when splitting kallsyms symbols per section for
    handling kcore files, problem found on a s390x system. (Jiri Olsa)

Infrastructure changes:

  - Prep work for the 'perf stat record' work that will allow generating
    perf.data files with counting data in addition to the sampling mode
    we have now (Jiri Olsa)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-29 10:29:18 +01:00
Wang Nan
4edf30e39e perf bpf: Collect perf_evsel in BPF object files
This patch creates a 'struct perf_evsel' for every probe in a BPF object
file(s) and fills 'struct evlist' with them. The previously introduced
dummy event is now removed. After this patch, the following command:

 # perf record --event filter.o ls

Can trace on each of the probes defined in filter.o.

The core of this patch is bpf__foreach_tev(), which calls a callback
function for each 'struct probe_trace_event' event for a bpf program
with each associated file descriptors. The add_bpf_event() callback
creates evsels by calling parse_events_add_tracepoint().

Since bpf-loader.c will not be built if libbpf is turned off, an empty
bpf__foreach_tev() is defined in bpf-loader.h to avoid build errors.

Committer notes:

Before:

  # /tmp/oldperf record --event /tmp/foo.o -a usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.198 MB perf.data ]
  # perf evlist
  /tmp/foo.o
  # perf evlist -v
  /tmp/foo.o: type: 1, size: 112, config: 0x9, { sample_period,
  sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD, disabled: 1,
  inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, sample_id_all: 1,
  exclude_guest: 1, mmap2: 1, comm_exec: 1

I.e. we create just the PERF_TYPE_SOFTWARE (type: 1),
PERF_COUNT_SW_DUMMY(config 0x9) event, now, with this patch:

  # perf record --event /tmp/foo.o -a usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.210 MB perf.data ]
  # perf evlist -v
  perf_bpf_probe:fork: type: 2, size: 112, config: 0x6bd, { sample_period,
  sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1,
  inherit: 1, mmap: 1, comm: 1, task: 1, sample_id_all: 1, exclude_guest:
  1, mmap2: 1, comm_exec: 1
  #

We now have a PERF_TYPE_SOFTWARE (type: 1), but the config states 0x6bd,
which is how, after setting up the event via the kprobes interface, the
'perf_bpf_probe:fork' event is accessible via the perf_event_open
syscall. This is all transient, as soon as the 'perf record' session
ends, these probes will go away.

To see how it looks like, lets try doing a neverending session, one that
expects a control+C to end:

  # perf record --event /tmp/foo.o -a

So, with that in place, we can use 'perf probe' to see what is in place:

  # perf probe -l
    perf_bpf_probe:fork  (on _do_fork@acme/git/linux/kernel/fork.c)

We also can use debugfs:

  [root@felicio ~]# cat /sys/kernel/debug/tracing/kprobe_events
  p:perf_bpf_probe/fork _text+638512

Ok, now lets stop and see if we got some forks:

  [root@felicio linux]# perf record --event /tmp/foo.o -a
  ^C[ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.325 MB perf.data (111 samples) ]

  [root@felicio linux]# perf script
      sshd  1271 [003] 81797.507678: perf_bpf_probe:fork: (ffffffff8109be30)
      sshd 18309 [000] 81797.524917: perf_bpf_probe:fork: (ffffffff8109be30)
      sshd 18309 [001] 81799.381603: perf_bpf_probe:fork: (ffffffff8109be30)
      sshd 18309 [001] 81799.408635: perf_bpf_probe:fork: (ffffffff8109be30)
  <SNIP>

Sure enough, we have 111 forks :-)

Callchains seems to work as well:

  # perf report --stdio --no-child
  # To display the perf.data header info, please use --header/--header-only options.
  #
  # Total Lost Samples: 0
  #
  # Samples: 562  of event 'perf_bpf_probe:fork'
  # Event count (approx.): 562
  #
  # Overhead  Command   Shared Object     Symbol
  # ........  ........  ................  ............
  #
      44.66%  sh        [kernel.vmlinux]  [k] _do_fork
                    |
                    ---_do_fork
                       entry_SYSCALL_64_fastpath
                       __libc_fork
                       make_child

    26.16%  make      [kernel.vmlinux]  [k] _do_fork
<SNIP>
  #

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 13:11:59 -03:00
Wang Nan
1e5e3ee8ff perf tools: Load eBPF object into kernel
This patch utilizes bpf_object__load() provided by libbpf to load all
objects into kernel.

Committer notes:

Testing it:

When using an incorrect kernel version number, i.e., having this in your
eBPF proggie:

  int _version __attribute__((section("version"), used)) = 0x40100;

For a 4.3.0-rc6+ kernel, say, this happens and needs checking at event
parsing time, to provide a better error report to the user:

  # perf record --event /tmp/foo.o sleep 1
  libbpf: load bpf program failed: Invalid argument
  libbpf: -- BEGIN DUMP LOG ---
  libbpf:

  libbpf: -- END LOG --
  libbpf: failed to load program 'fork=_do_fork'
  libbpf: failed to load object '/tmp/foo.o'
  event syntax error: '/tmp/foo.o'
                       \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel?

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events

If we instead make it match, i.e. use 0x40300 on this v4.3.0-rc6+
kernel, the whole process goes thru:

  # perf record --event /tmp/foo.o -a usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.202 MB perf.data ]
  # perf evlist -v
  /tmp/foo.o: type: 1, size: 112, config: 0x9, { sample_period,
  sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD, disabled: 1,
  inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, sample_id_all: 1,
  exclude_guest: 1, mmap2: 1, comm_exec: 1
  #

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-6-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 13:09:50 -03:00
Wang Nan
aa3abf30bb perf tools: Create probe points for BPF programs
This patch introduces bpf__{un,}probe() functions to enable callers to
create kprobe points based on section names a BPF program. It parses the
section names in the program and creates corresponding 'struct
perf_probe_event' structures. The parse_perf_probe_command() function is
used to do the main parsing work. The resuling 'struct perf_probe_event'
is stored into program private data for further using.

By utilizing the new probing API, this patch creates probe points during
event parsing.

To ensure probe points be removed correctly, register an atexit hook so
even perf quit through exit() bpf__clear() is still called, so probing
points are cleared. Note that bpf_clear() should be registered before
bpf__probe() is called, so failure of bpf__probe() can still trigger
bpf__clear() to remove probe points which are already probed.

strerror style error reporting scaffold is created by this patch.
bpf__strerror_probe() is the first error reporting function in
bpf-loader.c.

Committer note:

Trying it:

To build a test eBPF object file:

I am testing using a script I built from the 'perf test -v LLVM' output:

  $ cat ~/bin/hello-ebpf
  export KERNEL_INC_OPTIONS="-nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.8.3/include -I/home/acme/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/acme/git/linux/include -Iinclude -I/home/acme/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/acme/git/linux/include/uapi -Iinclude/generated/uapi -include /home/acme/git/linux/include/linux/kconfig.h"
  export WORKING_DIR=/lib/modules/4.2.0/build
  export CLANG_SOURCE=-
  export CLANG_OPTIONS=-xc

  OBJ=/tmp/foo.o
  rm -f $OBJ
  echo '__attribute__((section("fork=do_fork"), used)) int fork(void *ctx) {return 0;} char _license[] __attribute__((section("license"), used)) = "GPL";int _version __attribute__((section("version"), used)) = 0x40100;' | \
  clang -D__KERNEL__ $CLANG_OPTIONS $KERNEL_INC_OPTIONS -Wno-unused-value -Wno-pointer-sign -working-directory $WORKING_DIR -c "$CLANG_SOURCE" -target bpf -O2 -o /tmp/foo.o && file $OBJ

 ---

First asking to put a probe in a function not present in the kernel
(misses the initial _):

  $ perf record --event /tmp/foo.o sleep 1
  Probe point 'do_fork' not found.
  event syntax error: '/tmp/foo.o'
                       \___ You need to check probing points in BPF file

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events
  $

 ---

Now, with "__attribute__((section("fork=_do_fork"), used)):

 $ grep _do_fork /proc/kallsyms
 ffffffff81099ab0 T _do_fork
 $ perf record --event /tmp/foo.o sleep 1
 Failed to open kprobe_events: Permission denied
 event syntax error: '/tmp/foo.o'
                      \___ Permission denied

 ---

Cool, we need to provide some better hints, "kprobe_events" is too low
level, one doesn't strictly need to know the precise details of how
these things are put in place, so something that shows the command
needed to fix the permissions would be more helpful.

Lets try as root instead:

  # perf record --event /tmp/foo.o sleep 1
  Lowering default frequency rate to 1000.
  Please consider tweaking /proc/sys/kernel/perf_event_max_sample_rate.
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.013 MB perf.data ]
  # perf evlist
  /tmp/foo.o
  [root@felicio ~]# perf evlist -v
  /tmp/foo.o: type: 1, size: 112, config: 0x9, { sample_period,
  sample_freq }: 1000, sample_type: IP|TID|TIME|PERIOD, disabled: 1,
  inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1,
  sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1

 ---

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-5-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 12:48:13 -03:00
Wang Nan
84c86ca12b perf tools: Enable passing bpf object file to --event
By introducing new rules in tools/perf/util/parse-events.[ly], this
patch enables 'perf record --event bpf_file.o' to select events by an
eBPF object file. It calls parse_events_load_bpf() to load that file,
which uses bpf__prepare_load() and finally calls bpf_object__open() for
the object files.

After applying this patch, commands like:

 # perf record --event foo.o sleep

become possible.

However, at this point it is unable to link any useful things onto the
evsel list because the creating of probe points and BPF program
attaching have not been implemented.  Before real events are possible to
be extracted, to avoid perf report error because of empty evsel list,
this patch link a dummy evsel. The dummy event related code will be
removed when probing and extracting code is ready.

Commiter notes:

Using it:

  $ ls -la foo.o
  ls: cannot access foo.o: No such file or directory
  $ perf record --event foo.o sleep
  libbpf: failed to open foo.o: No such file or directory
  event syntax error: 'foo.o'
                       \___ BPF object file 'foo.o' is invalid

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events
  $

  $ file /tmp/build/perf/perf.o
  /tmp/build/perf/perf.o: ELF 64-bit LSB relocatable, x86-64, version 1 (SYSV), not stripped
  $ perf record --event /tmp/build/perf/perf.o sleep
  libbpf: /tmp/build/perf/perf.o is not an eBPF object file
  event syntax error: '/tmp/build/perf/perf.o'
                       \___ BPF object file '/tmp/build/perf/perf.o' is invalid

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events
  $

  $ file /tmp/foo.o
  /tmp/foo.o: ELF 64-bit LSB relocatable, no machine, version 1 (SYSV), not stripped
  $ perf record --event /tmp/foo.o sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.013 MB perf.data ]
  $ perf evlist
  /tmp/foo.o
  $ perf evlist  -v
  /tmp/foo.o: type: 1, size: 112, config: 0x9, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
  $

So, type 1 is PERF_TYPE_SOFTWARE, config 0x9 is PERF_COUNT_SW_DUMMY, ok.

  $ perf report --stdio
  Error:
  The perf.data file has no samples!
  # To display the perf.data header info, please use --header/--header-only options.
  #
  $

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 12:48:12 -03:00
Wang Nan
69d262a93a perf ebpf: Add the libbpf glue
The 'bpf-loader.[ch]' files are introduced in this patch. Which will be
the interface between perf and libbpf. bpf__prepare_load() resides in
bpf-loader.c. Following patches will enrich these two files.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 12:48:12 -03:00
Wang Nan
ed63f34c02 perf tools: Make perf depend on libbpf
By adding libbpf into perf's Makefile, this patch enables perf to build
libbpf if libelf is found and neither NO_LIBELF nor NO_LIBBPF is set.

The newly introduced code is similar to how libapi and libtraceevent
are wired into Makefile.perf.

MANIFEST is also updated for 'make perf-*-src-pkg'.

Append make_no_libbpf to tools/perf/tests/make.

The 'bpf' feature check is appended into default FEATURE_TESTS and
FEATURE_DISPLAY, so perf will check the API version of bpf in
/path/to/kernel/include/uapi/linux/bpf.h. Which should not fail except
when we are trying to port this code to an old kernel.

Error messages are also updated to notify users about the lack of BPF
support in 'perf record' if libelf is missing or the BPF API check
failed.

tools/lib/bpf is added to TAG_FOLDERS to allow us to navigate libbpf
files when working on perf using tools/perf/tags.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1444826502-49291-2-git-send-email-wangnan0@huawei.com
[ Document NO_LIBBPF in Makefile.perf, noted by Jiri Olsa ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 12:48:12 -03:00
Jiri Olsa
443f8c75e8 perf symbols: Fix endless loop in dso__split_kallsyms_for_kcore
Currently we split symbols based on the map comparison, but symbols are stored
within dso objects and maps could point into same dso objects (kernel maps).

Hence we could end up changing rbtree we are currently iterating and mess it
up. It's easily reproduced on s390x by running:

  $ perf record -a -- sleep 3
  $ perf buildid-list -i perf.data --with-hits

The fix is to compare dso objects instead.

Reported-by: Michael Petlan <mpetlan@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20151026135130.GA26003@krava.brq.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 11:19:30 -03:00
Wang Nan
374ce938aa perf tools: Enable pre-event inherit setting by config terms
This patch allows perf record setting event's attr.inherit bit by
config terms like:

  # perf record -e cycles/no-inherit/ ...
  # perf record -e cycles/inherit/ ...

So user can control inherit bit for each event separately.

In following example, a.out fork()s in main then do some complex
CPU intensive computations in both of its children.

Basic result with and without inherit:

  # perf record -e cycles -e instructions ./a.out
  [ perf record: Woken up 9 times to write data ]
  [ perf record: Captured and wrote 2.205 MB perf.data (47920 samples) ]
  # perf report --stdio
  # ...
  # Samples: 23K of event 'cycles'
  # Event count (approx.): 23641752891
  ...
  # Samples: 24K of event 'instructions'
  # Event count (approx.): 30428312415

  # perf record -i -e cycles -e instructions ./a.out
  [ perf record: Woken up 5 times to write data ]
  [ perf record: Captured and wrote 1.111 MB perf.data (24019 samples) ]
  ...
  # Samples: 12K of event 'cycles'
  # Event count (approx.): 11699501775
  ...
  # Samples: 12K of event 'instructions'
  # Event count (approx.): 15058023559

Cancel inherit for one event when globally enable:

  # perf record -e cycles/no-inherit/ -e instructions ./a.out
  [ perf record: Woken up 7 times to write data ]
  [ perf record: Captured and wrote 1.660 MB perf.data (36004 samples) ]
  ...
  # Samples: 12K of event 'cycles/no-inherit/'
  # Event count (approx.): 11895759282
 ...
  # Samples: 24K of event 'instructions'
  # Event count (approx.): 30668000441

Enable inherit for one event when globally disable:

  # perf record -i -e cycles/inherit/ -e instructions ./a.out
  [ perf record: Woken up 7 times to write data ]
  [ perf record: Captured and wrote 1.654 MB perf.data (35868 samples) ]
  ...
  # Samples: 23K of event 'cycles/inherit/'
  # Event count (approx.): 23285400229
  ...
  # Samples: 11K of event 'instructions'
  # Event count (approx.): 14969050259

Committer note:

One can check if the bit was set, in addition to seeing the result in
the perf.data file size as above by doing one of:

  # perf record -e cycles -e instructions -a usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.911 MB perf.data (63 samples) ]
  # perf evlist -v
  cycles: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ID|CPU|PERIOD, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
  instructions: size: 112, config: 0x1, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ID|CPU|PERIOD, read_format: ID, disabled: 1, inherit: 1, freq: 1, sample_id_all: 1, exclude_guest: 1
  #

So, the inherit bit was set in both, now, if we disable it globally using
--no-inherit:

  # perf record --no-inherit -e cycles -e instructions -a usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.910 MB perf.data (56 samples) ]
  # perf evlist -v
  cycles: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ID|CPU|PERIOD, read_format: ID, disabled: 1, mmap: 1, comm: 1, freq: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
  instructions: size: 112, config: 0x1, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ID|CPU|PERIOD, read_format: ID, disabled: 1, freq: 1, sample_id_all: 1, exclude_guest: 1

No inherit bit set, then disabling it and setting just on the cycles event:

  # perf record --no-inherit -e cycles/inherit/ -e instructions -a usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.909 MB perf.data (48 samples) ]
  # perf evlist -v
  cycles/inherit/: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ID|CPU|PERIOD, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
  instructions: size: 112, config: 0x1, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ID|CPU|PERIOD, read_format: ID, disabled: 1, freq: 1, sample_id_all: 1, exclude_guest: 1
  #

We can see it as well in by using a more verbose level of debug messages in
the tool that sets up the perf_event_attr, 'perf record' in this case:

  [root@zoo ~]# perf record -vv --no-inherit -e cycles/inherit/ -e instructions -a usleep 1
  ------------------------------------------------------------
  perf_event_attr:
    size                             112
    { sample_period, sample_freq }   4000
    sample_type                      IP|TID|TIME|ID|CPU|PERIOD
    read_format                      ID
    disabled                         1
    inherit                          1
    mmap                             1
    comm                             1
    freq                             1
    task                             1
    sample_id_all                    1
    exclude_guest                    1
    mmap2                            1
    comm_exec                        1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8
  sys_perf_event_open: pid -1  cpu 1  group_fd -1  flags 0x8
  sys_perf_event_open: pid -1  cpu 2  group_fd -1  flags 0x8
  sys_perf_event_open: pid -1  cpu 3  group_fd -1  flags 0x8
  ------------------------------------------------------------
  perf_event_attr:
    size                             112
    config                           0x1
    { sample_period, sample_freq }   4000
    sample_type                      IP|TID|TIME|ID|CPU|PERIOD
    read_format                      ID
    disabled                         1
    freq                             1
    sample_id_all                    1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8

<SNIP>

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446029705-199659-2-git-send-email-wangnan0@huawei.com
[ s/u64/bool/ for the perf_evsel_config_term inherit field - jolsa]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 11:19:16 -03:00
Dima Kogan
5baecbcd9c perf symbols: we can now read separate debug-info files based on a build ID
Recent GDB (at least on a vanilla Debian box) looks for debug information in

  /usr/lib/debug/.build-id/nn/nnnnnnn

where nn/nnnnnn is the build-id of the stripped ELF binary. This is
documented here:

  https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html

This was not working in perf because we didn't read the build id until
AFTER we searched for the separate debug information file. This patch
reads the build ID and THEN does the search.

Signed-off-by: Dima Kogan <dima@secretsauce.net>
Link: http://lkml.kernel.org/r/87si6pfwz4.fsf@secretsauce.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 10:04:27 -03:00
Dima Kogan
f2f3096888 perf symbols: Fix type error when reading a build-id
This was benign, but wrong. The build-id should live in a char[], not a char*[]

Signed-off-by: Dima Kogan <dima@secretsauce.net>
Link: http://lkml.kernel.org/r/87si6pfwz4.fsf@secretsauce.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-28 10:02:00 -03:00
Arnaldo Carvalho de Melo
f4efcce33d perf tools: Search for more options when passing args to -h
Recently 'perf <tool> -h' was made aware of arguments and would show
just the help for the arguments specified, but that required a strict
form, i.e.:

  $ perf -h --tui

worked, but:

  $ perf -h tui

didn't.

Make it support both cases and also look at the option help when neither
matches, so that he following examples works:

  $ perf report -h interface

   Usage: perf report [<options>]

    --gtk    Use the GTK2 interface
    --stdio  Use the stdio interface
    --tui    Use the TUI interface

  $ perf report -h stack

   Usage: perf report [<options>]

    -g, --call-graph <print_type,threshold[,print_limit],order,
                      sort_key[,branch]>
      Display call graph (stack chain/backtrace):

        print_type:  call graph printing style (graph|flat|fractal|none)
        threshold:   minimum call graph inclusion threshold (<percent>)
        print_limit: maximum number of call graph entry (<number>)
        order:       call graph order (caller|callee)
        sort_key:    call graph sort key (function|address)
        branch:      include last branch info to call graph (branch)

      Default: graph,0.5,caller,function
        --max-stack <n>   Set the maximum stack depth when parsing the
                          callchain, anything beyond the specified depth
                          will be ignored. Default: 127
  $

Suggested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-xzqvamzqv3cv0p6w3inhols3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-27 17:35:58 -03:00
Jiri Olsa
1e5a29318b perf stat: Cache aggregated map entries in extra cpumap
Currently any time we need to access socket or core id for given cpu, we
access the sysfs topology file.

Adding a cpus_aggr_map cpu_map to cache those entries.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Kan Liang <kan.liang@intel.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/1445784728-21732-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-27 15:08:07 -03:00
Jiri Olsa
2322f573f8 perf cpu_map: Add cpu_map__empty_new function
Adding cpu_map__empty_new interface to create empty cpumap with given
size. The cpumap entries are initialized with -1.

It'll be used for caching cpu_map in following patches.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1445784728-21732-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-27 15:05:36 -03:00
Jiri Olsa
af33998174 perf evsel: Move id_offset out of struct perf_evsel union member
Because the 'perf stat record' patches will use the id_offset member
together with the priv pointer.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Kan Liang <kan.liang@intel.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/1445784728-21732-29-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-27 15:04:29 -03:00
Namhyung Kim
c711836972 perf tools: Introduce usage_with_options_msg()
Now usage_with_options() setup a pager before printing message so normal
printf() or pr_err() will not be shown.  The usage_with_options_msg()
can be used to print some help message before usage strings.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.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/1445701767-12731-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-27 09:28:44 -03:00
Namhyung Kim
01b19455c0 perf tools: Setup pager when printing usage and help
It's annoying to see error or help message when command has many options
like in perf record, report or top.  So setup pager when print parser
error or help message - it should be OK since no UI is enabled at the
parsing time.  The usage_with_options() already disables it by calling
exit_browser() anyway.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Arnaldo 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/1445701767-12731-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-26 14:08:48 -03:00
Namhyung Kim
b272a59d83 perf report: Rename to --show-cpu-utilization
So that it can be more consistent with other --show-* options.  The old
name (--showcpuutilization) is provided only for compatibility.

Signed-off-by: Namhyung 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/1445701767-12731-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-26 14:06:04 -03:00
Namhyung Kim
a5f4a6932e perf tools: Improve ambiguous option help message
Currently if an option name is ambiguous it only prints first two
matched option names but no help.  It'd be better it could show all
possible names and help messages too.

Before:
  $ perf report --show
    Error: Ambiguous option: show (could be --show-total-period or
                                            --show-ref-call-graph)
   Usage: perf report [<options>]

After:
  $ perf report --show
    Error: Ambiguous option: show (could be --show-total-period or
                                            --show-ref-call-graph)
   Usage: perf report [<options>]

      -n, --show-nr-samples
                              Show a column with the number of samples
          --showcpuutilization
                              Show sample percentage for different cpu modes
      -I, --show-info         Display extended information about perf.data file
          --show-total-period
                              Show a column with the sum of periods
          --show-ref-call-graph
                              Show callgraph from reference event

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Arnaldo 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/1445701767-12731-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-26 13:59:06 -03:00
Ingo Molnar
4341801873 perf/core improvements:
New features:
 
 - Show ordered command line options when -h is used or when an
   unknown options is specified (Arnaldo Carvalho de Melo)
 
 - If options are passed after -h, show just its descriptions, not
   all options (Arnaldo Carvalho de Melo)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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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 from Arnaldo Carvalho de Melo:

New user-visible features:

  - Show ordered command line options when -h is used or when an
    unknown option is specified. (Arnaldo Carvalho de Melo)

  - If options are passed after -h, show just its descriptions, not
    all options. (Arnaldo Carvalho de Melo)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-25 09:40:31 +01:00
Arnaldo Carvalho de Melo
161d904178 perf tools: Provide help for subset of options
Some tools have a lot of options, so, providing a way to show help just
for some of them may come handy:

  $ perf report -h --tui

   Usage: perf report [<options>]

        --tui             Use the TUI interface

  $ perf report -h --tui --showcpuutilization -b -c

   Usage: perf report [<options>]

    -b, --branch-stack    use branch records for per branch histogram filling
    -c, --comms <comm[,comm...]>
                          only consider symbols in these comms
        --showcpuutilization
                          Show sample percentage for different cpu modes
        --tui             Use the TUI interface

  $

Using it with perf bash completion is also handy, just make sure you
source the needed file:

  $ . ~/git/linux/tools/perf/perf-completion.sh

Then press tab/tab after -- to see a list of options, put them after -h
and only the options chosen will have its help presented:

  $ perf report -h --
  --asm-raw              --demangle-kernel      --group
  --kallsyms             --pretty               --stdio
  --branch-history       --disassembler-style   --gtk
  --max-stack            --showcpuutilization   --symbol-filter
  --branch-stack         --dsos                 --header
  --mem-mode             --show-info            --symbols
  --call-graph           --dump-raw-trace       --header-only
  --modules              --show-nr-samples      --symfs
  --children             --exclude-other        --hide-unresolved
  --objdump              --show-ref-call-graph  --threads
  --column-widths        --fields               --ignore-callees
  --parent               --show-total-period    --tid
  --comms                --field-separator      --input
  --percentage           --socket-filter        --tui
  --cpu                  --force                --inverted
  --percent-limit        --sort                 --verbose
  --demangle             --full-source-path     --itrace
  --pid                  --source               --vmlinux
  $ perf report -h --socket-filter

   Usage: perf report [<options>]

      --socket-filter <n>
                  only show processor socket that match with this filter

Suggested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-83mcdd3wj0379jcgea8w0fxa@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-23 21:50:50 -03:00