linux-toradex.git/tools/perf/builtin-report.c, branch v4.2.7

perf report: Fill in the missing session freeing after an error occurs

2015-07-01T20:53:49+00:00

When an error occurs an error value is just returned without freeing the
session. So allocating and freeing session have to be matched as a pair
even if an error occurs.

Signed-off-by: Taeung Song 
Acked-by: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/1435652124-22414-6-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Check access permission when reading symbol files

2015-06-26T15:11:53+00:00

There 2 problems when reading symbols files:

*  It doesn't report any errors even if when users specify symbol
   files which don't exist with --kallsyms or --vmlinux. The result
   just shows the address without symbols, which is not what is expected.
   So it's better to report errors and exit the program.

*  When using command perf report --kallsyms=/proc/kallsyms with a
   non-root user, symbols are resolved. Then select one symbol and
   annotate it, it reports the error as the following:
   Can't annotate __clear_user: No vmlinux file with build id xxx was
   found.

   The problem is caused by reading /proc/kcore without access permission.
   /proc/kcore requires CAP_SYS_RAWIO capability to access, so it needs to
   change access permission to allow a specific user to read /proc/kcore or
   use root to execute the perf command.

This patch is to report errors when symbol files specified by users
don't exist. And check access permission of /proc/kcore when reading it.

Signed-off-by: Li Zhang 
Cc: Sukadev Bhattiprolu 
Link: http://lkml.kernel.org/r/1434704253-2632-1-git-send-email-zhlcindy@linux.vnet.ibm.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 hists: Reducing arguments of hist_entry_iter__add()

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

The evsel and sample arguments are to set iter for later use.  As it
also receives an iter as another argument, just set them before calling
the function.

Signed-off-by: Namhyung Kim 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1432022650-18205-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Do not restrict -T option by other options

2015-05-12T12:59:51+00:00

It seems there's no reason to suppress per-thread event stat by -T
option when -s or -p option is used.  Make it work with those options.

Signed-off-by: Namhyung Kim 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1431351879-23798-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Force tty output if -T/--thread option is given

2015-05-12T12:59:48+00:00

The -T/--thread option is supported only on --stdio mode (at least for
now).  So enforce the tty output if the option was requested.

Signed-off-by: Namhyung Kim 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1431184784-30525-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

Merge branch 'perf/urgent' into perf/core, to resolve conflicts

2015-05-11T09:56:27+00:00

Conflicts:
	tools/perf/builtin-kmem.c

Signed-off-by: Ingo Molnar

perf machine: Protect the machine->threads with a rwlock

2015-05-08T19:19:27+00:00

In addition to using refcounts for the struct thread lifetime
management, we need to protect access to machine->threads from
concurrent access.

That happens in 'perf top', where a thread processes events, inserting
and deleting entries from that rb_tree while another thread decays
hist_entries, that end up dropping references and ultimately deleting
threads from the rb_tree and releasing its resources when no further
hist_entry (or other data structures, like in 'perf sched') references
it.

So the rule is the same for refcounts + protected trees in the kernel,
get the tree lock, find object, bump the refcount, drop the tree lock,
return, use object, drop the refcount if no more use of it is needed,
keep it if storing it in some other data structure, drop when releasing
that data structure.

I.e. pair "t = machine__find(new)_thread()" with a "thread__put(t)", and
"perf_event__preprocess_sample(&al)" with "addr_location__put(&al)".

The addr_location__put() one is because as we return references to
several data structures, we may end up adding more reference counting
for the other data structures and then we'll drop it at
addr_location__put() time.

Acked-by: David Ahern 
Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: Don Zickus 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-bs9rt4n0jw3hi9f3zxyy3xln@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Add Instruction Tracing support

2015-05-04T15:43:50+00:00

Add support for decoding an AUX area assuming it contains instruction
tracing data.

Signed-off-by: Adrian Hunter 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1429903807-20559-4-git-send-email-adrian.hunter@intel.com
[ Do not use -Z as an alternative to --itrace ]
[ Fixed initialization of itrace_synth_opts struct fields on older gcc versions ]
Signed-off-by: Arnaldo Carvalho de Melo