linux-stable.git/tools/perf/util/session.c, branch v4.2.3

perf tools: Add reference counting for cpu_map object

2015-06-25T18:15:50+00:00

Adding refference counting for cpu_map object, so it could be easily
shared among other objects.

Using cpu_map__put instead cpu_map__delete and making cpu_map__delete
static.

Signed-off-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1435012588-9007-4-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Print a newline before dumping Aggregated stats

2015-06-23T21:21:43+00:00

When dumping events with 'perf report -D' the event print always starts
with a newline (see dump_event()).

Do the same with the "Aggregated stats" print so that it is not jammed
up against the last event print.

Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/1435045969-15999-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf session: Print a newline when dumping PERF_RECORD_FINISHED_ROUND

2015-06-23T21:21:43+00:00

With 'perf report -D' the PERF_RECORD_FINISHED_ROUND event was printed
without a newline, resulting in:

	0x91a18 [0x8]: PERF_RECORD_FINISHED_ROUNDAggregated stats

Other events print their details, but PERF_RECORD_FINISHED_ROUND doesn't
have any so just add a print for a newline.

Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/1435045969-15999-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Configurable per thread proc map processing time out

2015-06-19T21:27:13+00:00

The time out to limit the individual proc map processing was hard code
to 500ms. This patch introduce a new option --proc-map-timeout to make
the time limit configurable.

Signed-off-by: Kan Liang 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Ying Huang 
Link: http://lkml.kernel.org/r/1434549071-25611-2-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add time out to force stop proc map processing

2015-06-19T21:20:15+00:00

System wide sampling like 'perf top' or 'perf record -a' read all
threads /proc/xxx/maps before sampling. If there are any threads which
generating a keeping growing huge maps, perf will do infinite loop
during synthesizing. Nothing will be sampled.

This patch fixes this issue by adding per-thread timeout to force stop
this kind of endless proc map processing.

PERF_RECORD_MISC_PROC_MAP_PARSE_TIME_OUT is introduced to indicate that
the mmap record are truncated by time out. User will get warning
notification when truncated mmap records are detected.

Reported-by: Ying Huang 
Signed-off-by: Kan Liang 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Ying Huang 
Link: http://lkml.kernel.org/r/1434549071-25611-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Ensure thread-stack is flushed

2015-06-19T19:03:33+00:00

The thread-stack represents a thread's current stack.  When a thread
exits there can still be many functions on the stack e.g. exit() can be
called many levels deep, so all the callers will never return.  To get
that information output, the thread-stack must be flushed.

Previously it was assumed the thread-stack would be flushed when the
struct thread was deleted.  With thread ref-counting it is no longer
clear when that will be, if ever. So instead explicitly flush all the
thread-stacks at the end of a session.

Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/1432906425-9911-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix a problem when opening old perf.data with different byte order

2015-06-17T19:28:08+00:00

Following error occurs when trying to use 'perf report' on x86_64 to
cross analysis a perf.data generated by an old perf on a big-endian
machine:

 # perf report
 *** Error in `/home/w00229757/perf': free(): invalid next size (fast): 0x00000000032c99f0 ***
 ======= Backtrace: =========
 /lib64/libc.so.6(+0x6eeef)[0x7ff6ff7e2eef]
 /lib64/libc.so.6(+0x78cae)[0x7ff6ff7eccae]
 /lib64/libc.so.6(+0x79987)[0x7ff6ff7ed987]
 /path/to/perf[0x4ac734]
 /path/to/perf[0x4ac829]
 /path/to/perf(perf_header__process_sections+0x129)[0x4ad2c9]
 /path/to/perf(perf_session__read_header+0x2e1)[0x4ad9e1]
 /path/to/perf(perf_session__new+0x168)[0x4bd458]
 /path/to/perf(cmd_report+0xfa0)[0x43eb70]
 /path/to/perf[0x47adc3]
 /path/to/perf(main+0x5f6)[0x42fd06]
 /lib64/libc.so.6(__libc_start_main+0xf5)[0x7ff6ff795bd5]
 /path/to/perf[0x42fe35]
 ======= Memory map: ========
 [SNIP]

The bug is in perf_event__attr_swap(). It swaps all fields in 'struct
perf_event_attr' without checking whether the swapped field exist or
not. In addition, in read_event_desc() allocs memory for attr according
to size read from perf.data.

Therefore, if the perf.data is collected by an old perf (without
aux_watermark, for example), when perf_event__attr_swap() swaping
attr->aux_watermark it destroy malloc's metadata.

This patch introduces boundary checking in perf_event__attr_swap(). It
adds macros bswap_field_64 and bswap_field_32 into
perf_event__attr_swap() to make it only swap exist fields.

Signed-off-by: Wang Nan 
Acked-by: Jiri Olsa 
Cc: Ingo Molnar 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1434534999-85347-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix build failure on 32-bit arch

2015-06-11T14:14:21+00:00

Failed in 32bit arch build like this:

    CC       /opt/h00206996/output/perf/arm32/builtin-record.o
  util/session.c: In function ‘perf_session__warn_about_errors’:
  util/session.c:1304:9: error: format ‘%lu’ expects argument of type ‘long unsigned int’,
                         but argument 2 has type ‘long long unsigned int’ [-Werror=format=]

  builtin-report.c: In function ‘perf_evlist__tty_browse_hists’:
  builtin-report.c:323:2: error: format ‘%lu’ expects argument of type ‘long unsigned int’,
                          but argument 3 has type ‘u64’ [-Werror=format=]

Replace %lu format strings in warning message with PRIu64 for u64
'total_lost_samples' to fix this problem.

Signed-off-by: He Kuang 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Peter Zijlstra 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1434026664-71642-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: handle PERF_RECORD_LOST_SAMPLES

2015-06-07T14:09:06+00:00

This patch modifies the perf tool to handle the new RECORD type,
PERF_RECORD_LOST_SAMPLES.

The number of lost-sample events is stored in
.nr_events[PERF_RECORD_LOST_SAMPLES]. The exact number of samples
which the kernel dropped is stored in total_lost_samples.

When the percentage of dropped samples is greater than 5%, a warning
is printed.

Here are some examples:

Eg 1, Recording different frequently-occurring events is safe with the
      patch. Only a very low drop rate is associated with such actions.

$ perf record -e '{cycles:p,instructions:p}' -c 20003 --no-time ~/tchain ~/tchain

$ perf report -D | tail
          SAMPLE events:     120243
           MMAP2 events:          5
    LOST_SAMPLES events:         24
  FINISHED_ROUND events:         15
cycles:p stats:
           TOTAL events:      59348
          SAMPLE events:      59348
instructions:p stats:
           TOTAL events:      60895
          SAMPLE events:      60895

$ perf report --stdio --group
 # To display the perf.data header info, please use --header/--header-only options.
 #
 #
 # Total Lost Samples: 24
 #
 # Samples: 120K of event 'anon group { cycles:p, instructions:p }'
 # Event count (approx.): 24048600000
 #
 #         Overhead  Command      Shared Object     Symbol
 # ................  ...........  ................
 ..................................
 #
    99.74%  99.86%  tchain_edit  tchain_edit       [.] f3
     0.09%   0.02%  tchain_edit  tchain_edit       [.] f2
     0.04%   0.00%  tchain_edit  [kernel.vmlinux]  [k] ixgbe_read_reg

Eg 2, Recording the same thing multiple times can lead to high drop
      rate, but it is not a useful configuration.

$ perf record -e '{cycles:p,cycles:p}' -c 20003 --no-time ~/tchain
Warning: Processed 600592 samples and lost 99.73% samples!
[perf record: Woken up 148 times to write data]
[perf record: Captured and wrote 36.922 MB perf.data (1206322 samples)]
[perf record: Woken up 1 times to write data]
[perf record: Captured and wrote 0.121 MB perf.data (1629 samples)]

Signed-off-by: Kan Liang 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Andrew Morton 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: acme@infradead.org
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1431285195-14269-9-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar

perf session: Fix perf_session__peek_event()

2015-05-27T15:21:43+00:00

perf_session__peek_event() generally leverages there being a single mmap
of the perf.data file, however on 32-bit platforms when there is more
that 32MiB of data, then there are multiple mmaps, so
perf_session__peek_event() reads from the file.

In that case a couple of bugs were exposed (note how the seg. fault
appears with >32M of data):

   $ perf record --per-thread -e intel_bts// ../rtit-tests/loopy 1000000
   [ perf record: Woken up 13 times to write data ]
   [ perf record: Captured and wrote 24.568 MB perf.data ]
   $ perf script > /dev/null
   $ perf record --per-thread -e intel_bts// ../rtit-tests/loopy 10000000
   [ perf record: Woken up 136 times to write data ]
   [ perf record: Captured and wrote 270.794 MB perf.data ]
   $ perf script > /dev/null
   Segmentation fault (core dumped)

The wrong address was being passed to the readn() function and the
buffer size was not being checked.

Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/1432040746-1755-5-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo