linux-stable.git/tools/perf/util/session.c, branch v4.4

perf session: Add missing newlines to some pr_err() calls

2015-11-11T21:41:31+00:00

Before:

  [acme@zoo linux]$ perf evlist
  WARNING: The perf.data file's data size field is 0 which is unexpected.
  Was the 'perf record' command properly terminated?
  non matching sample_type[acme@zoo linux]$

After:

  [acme@zoo linux]$ perf evlist
  WARNING: The perf.data file's data size field is 0 which is unexpected.
  Was the 'perf record' command properly terminated?
  non matching sample_type
  [acme@zoo linux]$

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-wscok3a2s7yrj8156oc2r6qe@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf top: Register idle thread

2015-10-01T12:54:33+00:00

The perf top didn't add the idle/swapper thread to the machine's thread
list and its comm was displayed as ':0'.  Fix it.

Signed-off-by: Namhyung Kim 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1443577526-3240-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf script: Add a setting for maximum stack depth

2015-09-28T20:08:48+00:00

Add a setting for maximum stack depth in preparation for allowing for
synthesized callchains.

Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/1443186956-18718-19-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf session: Warn when AUX data has been lost

2015-09-28T19:51:33+00:00

By default 'perf record' will postprocess the perf.data file to
determine build-ids.  When that happens, the number of lost perf events
is displayed.

Make that also happen for AUX events.

Signed-off-by: Adrian Hunter 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/1443186956-18718-7-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

Merge branch 'perf/urgent' into perf/core to pick up fixes before pulling new changes

2015-09-23T07:42:11+00:00

Signed-off-by: Ingo Molnar

perf record: Avoid infinite loop at buildid processing with no samples

2015-09-18T15:31:40+00:00

If a session contains no events, we can get stuck in an infinite loop in
__perf_session__process_events, with a non-zero file_size and data_offset, but
a zero data_size.

In this case, we can mmap the entirety of the file (consisting of the file and
attribute headers), and fetch_mmaped_event will correctly refuse to read any
(unmapped and non-existent) event headers. This causes
__perf_session__process_events to unmap the file and retry with the exact same
parameters, getting stuck in an infinite loop.

This has been observed to result in an exit-time hang when counting
rare/unschedulable events with perf record, and can be triggered artificially
with the script below:

  ----
  #!/bin/sh
  printf "REPRO: launching perf\n";
  ./perf record -e software/config=9/ sleep 1 &
  PERF_PID=$!;
  sleep 0.002;
  kill -2 $PERF_PID;
  printf "REPRO: waiting for perf (%d) to exit...\n" "$PERF_PID";
  wait $PERF_PID;
  printf "REPRO: perf exited\n";
  ----

To avoid this, have __perf_session__process_events bail out early when
the file has no data (i.e. it has no events).

Commiter note:

I only managed to reproduce this when setting
/proc/sys/kernel/kptr_restrict to '1' and changing the code to
purposefully not process any samples and no synthesized samples, i.e.
kptr_restrict prevents 'record' from synthesizing the kernel mmaps for
vmlinux + modules and since it is a workload started from perf, we don't
synthesize mmap/comm records for existing threads.

Adrian Hunter managed to reproduce it in his environment tho.

Signed-off-by: Mark Rutland 
Tested-by: Arnaldo Carvalho de Melo 
Tested-by: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1442423929-12253-1-git-send-email-mark.rutland@arm.com
Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Add pointer to sample's environment

2015-09-14T15:50:29+00:00

The 'struct machine' represents the machine where the samples were/are
being collected, and we also have a 'struct perf_env' with extra details
about such machine, that we were collecting at 'perf.data' creation time
but we also needed when no perf.data file is being used, such as in
'perf top'.

So, get those structs closer together, as they provide a bigger picture
of the sample's environment.

In 'perf session', when the file argument is NULL, we can assume that
the tool is sampling the running machine, so point machine->env to
the global put in place in previous patches, while set it to the
perf_header.env one when reading from a file.

This paves the way for machine->env to be used in
perf_event__preprocess_sample to populate addr_location.socket.

Tested-by: Wang Nan 
Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-2ajotl0khscutm68exictoy9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf env: Move perf_env out of header.h and session.c into separate object

2015-09-14T15:50:19+00:00

Since it can be used separately from 'perf_session' and 'perf_header',
move it to separate include file and object, next csets will try to move
a perf_env__init() routine.

Tested-by: Wang Nan 
Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-ff2rw99tsn670y1b6gxbwdsi@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf session: Don't call dump_sample() when evsel is NULL

2015-09-04T15:01:04+00:00

Need to check evsel before passing it to dump_sample().

Signed-off-by: Kan Liang 
Cc: Adrian Hunter 
Cc: Andi Kleen 
Cc: Andy Lutomirski 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1441283463-51050-5-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Store the cpu socket and core ids in the perf.data header

2015-09-02T19:30:47+00:00

This patch stores the cpu socket_id and core_id in a perf.data header,
and reads them into the perf_env struct when processing perf.data files.

The changes modifies the CPU_TOPOLOGY section, making sure it is
backward/forward compatible.

The patch checks the section size before reading the core and socket ids.

It never reads data crossing the section boundary.  An old perf binary
without this patch can also correctly read the perf.data from a new perf
with this patch.

Because the new info is added at the end of the cpu_topology section, an
old perf tool ignores the extra data.

Examples:

1. New perf with this patch read perf.data from an old perf without the
   patch:

  $ perf_new report -i perf_old.data --header-only -I
  ......
  # sibling threads : 33
  # sibling threads : 34
  # sibling threads : 35
  # Core ID and Socket ID information is not available
  # node0 meminfo  : total = 32823872 kB, free = 29315548 kB
  # node0 cpu list : 0-17,36-53
  ......

2. Old perf without the patch reads perf.data from a new perf with the
   patch:

  $ perf_old report -i perf_new.data --header-only -I
  ......
  # sibling threads : 33
  # sibling threads : 34
  # sibling threads : 35
  # node0 meminfo  : total = 32823872 kB, free = 29190932 kB
  # node0 cpu list : 0-17,36-53
  ......

3. New perf read new perf.data:

  $ perf_new report -i perf_new.data --header-only -I
  ......
  # sibling threads : 33
  # sibling threads : 34
  # sibling threads : 35
  # CPU 0: Core ID 0, Socket ID 0
  # CPU 1: Core ID 1, Socket ID 0
  ......
  # CPU 61: Core ID 10, Socket ID 1
  # CPU 62: Core ID 11, Socket ID 1
  # CPU 63: Core ID 16, Socket ID 1
  # node0 meminfo  : total = 32823872 kB, free = 29190932 kB
  # node0 cpu list : 0-17,36-53

Signed-off-by: Kan Liang 
Cc: Andi Kleen 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/1441115893-22006-2-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo