linux-stable.git/tools/perf, branch linux-4.18.y

perf stat: Handle different PMU names with common prefix

2018-11-21T08:22:06+00:00

commit ea1fa48c055f833eb25f0c33188feecb7002ada5 upstream.

On s390 the CPU Measurement Facility for counters now supports
2 PMUs named cpum_cf (CPU Measurement Facility for counters) and
cpum_cf_diag (CPU Measurement Facility for diagnostic counters)
for one and the same CPU.

Running command

 [root@s35lp76 perf]# ./perf stat -e tx_c_tend \
	 -- ~/mytests/cf-tx-events 1

 Measuring transactions
 TX_C_TABORT_NO_SPECIAL: 0 expected:0
 TX_C_TABORT_SPECIAL: 0 expected:0
 TX_C_TEND: 1 expected:1
 TX_NC_TABORT: 11 expected:11
 TX_NC_TEND: 1 expected:1

 Performance counter stats for '/root/mytests/cf-tx-events 1':

  2      tx_c_tend

      0.002120091 seconds time elapsed

      0.000121000 seconds user
      0.002127000 seconds sys

 [root@s35lp76 perf]#

displays output which is unexpected (and wrong):

  2      tx_c_tend

The test program definitely triggers only one transaction, as shown
in line 'TX_C_TEND: 1 expected:1'.

This is caused by the following call sequence:

pmu_lookup() scans and installs a PMU.
+--> pmu_aliases() parses all aliases in directory
		...//events/* which are file names.
     +--> pmu_aliases_parse() Read each file in directory and create
                      an new alias entry. This is done with
          +--> perf_pmu__new_alias() and
	       +--> __perf_pmu__new_alias() which also check for
	                   identical alias names.

After pmu_aliases() returns, a complete list of event names
for this pmu has been created. Now function

pmu_add_cpu_aliases()   is called to add the events listed in the json
|                       files to the alias list of the cpu.
+--> perf_pmu__find_map()  Returns a pointer to the json events.

Now function pmu_add_cpu_aliases() scans through all events listed
in the JSON files for this CPU.
Each json event pmu name is compared with the current PMU being
built up and if they mismatch, the json event is added to the
current PMUs alias list.
To avoid duplicate entries the following comparison is done:

	if (!is_arm_pmu_core(name)) {
	     pname = pe->pmu ? pe->pmu : "cpu";
	     if (strncmp(pname, name, strlen(pname)))
		     continue;
     }

The culprit is the strncmp() function.

Using current s390 PMU naming, the first PMU is 'cpum_cf'
and a long list of events is added, among them 'tx_c_tend'

When the second PMU named 'cpum_cf_diag' is added, only one event
named 'CF_DIAG' is added by the pmu_aliases()  function.

Now function pmu_add_cpu_aliases() is invoked for PMU 'cpum_cf_diag'.
Since the CPUID string is the same for both PMUs, json file events
for PMU named 'cpum_cf' are added to the PMU 'cpm_cf_diag'

This happens because the strncmp() actually compares:

     strncmp("cpum_cf", "cpum_cf_diag", 6);

The first parameter is the pmu name taken from the event in
the json file. The second parameter is the pmu name of the PMU
currently being built.
They are different, but the length of the compare only tests the
common prefix and this returns 0(true) when it should return false.

Now all events for PMU cpum_cf are added to the alias list for pmu
cpum_cf_diag.

Later on in function parse_events_add_pmu() the event 'tx_c_end' is
searched in all available PMUs and found twice, adding it two
times to the evsel_list global variable which is the root
of all events. This results in a counter value of 2 instead
of 1.

Output with this patch:

 [root@s35lp76 perf]# ./perf stat -e tx_c_tend \
			-- ~/mytests/cf-tx-events 1
 Measuring transactions
 TX_C_TABORT_NO_SPECIAL: 0 expected:0
 TX_C_TABORT_SPECIAL: 0 expected:0
 TX_C_TEND: 1 expected:1
 TX_NC_TABORT: 11 expected:11
 TX_NC_TEND: 1 expected:1

 Performance counter stats for '/root/mytests/cf-tx-events 1':

                  1      tx_c_tend

      0.001815365 seconds time elapsed

      0.000123000 seconds user
      0.001756000 seconds sys

 [root@s35lp76 perf]#

Signed-off-by: Thomas Richter 
Reviewed-by: Hendrik Brueckner 
Reviewed-by: Sebastien Boisvert 
Cc: Heiko Carstens 
Cc: Kan Liang 
Cc: Martin Schwidefsky 
Cc: stable@vger.kernel.org
Fixes: 292c34c10249 ("perf pmu: Fix core PMU alias list for X86 platform")
Link: http://lkml.kernel.org/r/20181023151616.78193-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Greg Kroah-Hartman

perf tests: Fix record+probe_libc_inet_pton.sh without ping's debuginfo

2018-11-13T19:12:25+00:00

[ Upstream commit 1632936480a53d85ef3012cd9f290e247251cbb9 ]

When we don't have the iputils-debuginfo package installed, i.e. when we
don't have the DWARF information needed to resolve ping's samples, we
end up failing this 'perf test' entry:

  # perf test ping
  62: probe libc's inet_pton & backtrace it with ping       : Ok
  # rpm -e iputils-debuginfo
  # perf test ping
  62: probe libc's inet_pton & backtrace it with ping       : FAILED!
  #

Fix it to accept "[unknown]" where the symbol + offset, when resolved,
is expected.

I think this will fail in the other arches as well, but since I can't
test now, I'm leaving s390x and ppc cases as-is.

Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: David Ahern 
Cc: Hendrik Brueckner 
Cc: Jiri Olsa 
Cc: Kim Phillips 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Naveen N. Rao 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Sukadev Bhattiprolu 
Cc: Thomas Richter 
Cc: Wang Nan 
Fixes: 7903a7086723 ("perf script: Show symbol offsets by default")
Link: https://lkml.kernel.org/n/tip-hnizqwqrs03vcq1b74yao0f6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

perf strbuf: Match va_{add,copy} with va_end

2018-11-13T19:12:21+00:00

[ Upstream commit ce49d8436cffa9b7a6a5f110879d53e89dbc6746 ]

Ensure that all code paths in strbuf_addv() call va_end() on the
ap_saved copy that was made.

Fixes the following coverity complaint:

  Error: VARARGS (CWE-237): [#def683]
  tools/perf/util/strbuf.c:106: missing_va_end: va_end was not called
  for "ap_saved".

Signed-off-by: Sanskriti Sharma 
Reviewed-by: Jiri Olsa 
Cc: Joe Lawrence 
Link: http://lkml.kernel.org/r/1538490554-8161-2-git-send-email-sansharm@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

perf tools: Cleanup trace-event-info 'tdata' leak

2018-11-13T19:12:20+00:00

[ Upstream commit faedbf3fd19f2511a39397f76359e4cc6ee93072 ]

Free tracing_data structure in tracing_data_get() error paths.

Fixes the following coverity complaint:

  Error: RESOURCE_LEAK (CWE-772):
  leaked_storage: Variable "tdata" going out of scope leaks the storage

Signed-off-by: Sanskriti Sharma 
Reviewed-by: Jiri Olsa 
Cc: Joe Lawrence 
Link: http://lkml.kernel.org/r/1538490554-8161-3-git-send-email-sansharm@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

perf tools: Free temporary 'sys' string in read_event_files()

2018-11-13T19:12:20+00:00

[ Upstream commit 1e44224fb0528b4c0cc176bde2bb31e9127eb14b ]

For each system in a given pevent, read_event_files() reads in a
temporary 'sys' string.  Be sure to free this string before moving onto
to the next system and/or leaving read_event_files().

Fixes the following coverity complaints:

  Error: RESOURCE_LEAK (CWE-772):

  tools/perf/util/trace-event-read.c:343: overwrite_var: Overwriting
  "sys" in "sys = read_string()" leaks the storage that "sys" points to.

  tools/perf/util/trace-event-read.c:353: leaked_storage: Variable "sys"
  going out of scope leaks the storage it points to.

Signed-off-by: Sanskriti Sharma 
Reviewed-by: Jiri Olsa 
Cc: Joe Lawrence 
Link: http://lkml.kernel.org/r/1538490554-8161-6-git-send-email-sansharm@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

perf report: Don't crash on invalid inline debug information

2018-11-13T19:12:18+00:00

[ Upstream commit d4046e8e17b9f378cb861982ef71c63911b5dff3 ]

When the function name for an inline frame is invalid, we must not try
to demangle this symbol, otherwise we crash with:

  #0  0x0000555555895c01 in bfd_demangle ()
  #1  0x0000555555823262 in demangle_sym (dso=0x555555d92b90, elf_name=0x0, kmodule=0) at util/symbol-elf.c:215
  #2  dso__demangle_sym (dso=dso@entry=0x555555d92b90, kmodule=, kmodule@entry=0, elf_name=elf_name@entry=0x0) at util/symbol-elf.c:400
  #3  0x00005555557fef4b in new_inline_sym (funcname=0x0, base_sym=0x555555d92b90, dso=0x555555d92b90) at util/srcline.c:89
  #4  inline_list__append_dso_a2l (dso=dso@entry=0x555555c7bb00, node=node@entry=0x555555e31810, sym=sym@entry=0x555555d92b90) at util/srcline.c:264
  #5  0x00005555557ff27f in addr2line (dso_name=dso_name@entry=0x555555d92430 "/home/milian/.debug/.build-id/f7/186d14bb94f3c6161c010926da66033d24fce5/elf", addr=addr@entry=2888, file=file@entry=0x0,
      line=line@entry=0x0, dso=dso@entry=0x555555c7bb00, unwind_inlines=unwind_inlines@entry=true, node=0x555555e31810, sym=0x555555d92b90) at util/srcline.c:313
  #6  0x00005555557ffe7c in addr2inlines (sym=0x555555d92b90, dso=0x555555c7bb00, addr=2888, dso_name=0x555555d92430 "/home/milian/.debug/.build-id/f7/186d14bb94f3c6161c010926da66033d24fce5/elf")
      at util/srcline.c:358

So instead handle the case where we get invalid function names for
inlined frames and use a fallback '??' function name instead.

While this crash was originally reported by Hadrien for rust code, I can
now also reproduce it with trivial C++ code. Indeed, it seems like
libbfd fails to interpret the debug information for the inline frame
symbol name:

  $ addr2line -e /home/milian/.debug/.build-id/f7/186d14bb94f3c6161c010926da66033d24fce5/elf -if b48
  main
  /usr/include/c++/8.2.1/complex:610
  ??
  /usr/include/c++/8.2.1/complex:618
  ??
  /usr/include/c++/8.2.1/complex:675
  ??
  /usr/include/c++/8.2.1/complex:685
  main
  /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39

I've reported this bug upstream and also attached a patch there which
should fix this issue:

https://sourceware.org/bugzilla/show_bug.cgi?id=23715

Reported-by: Hadrien Grasland 
Signed-off-by: Milian Wolff 
Cc: Jin Yao 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Fixes: a64489c56c30 ("perf report: Find the inline stack for a given address")
[ The above 'Fixes:' cset is where originally the problem was
  introduced, i.e.  using a2l->funcname without checking if it is NULL,
  but this current patch fixes the current codebase, i.e. multiple csets
  were applied after a64489c56c30 before the problem was reported by Hadrien ]
Link: http://lkml.kernel.org/r/20180926135207.30263-3-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

perf cpu_map: Align cpu map synthesized events properly.

2018-11-13T19:12:17+00:00

[ Upstream commit 0ed149cf5239cc6e7e65bf00f769e8f1e91076c0 ]

The size of the resulting cpu map can be smaller than a multiple of
sizeof(u64), resulting in SIGBUS on cpus like Sparc as the next event
will not be aligned properly.

Signed-off-by: David S. Miller 
Cc: Jiri Olsa 
Cc: Kan Liang 
Fixes: 6c872901af07 ("perf cpu_map: Add cpu_map event synthesize function")
Link: http://lkml.kernel.org/r/20181011.224655.716771175766946817.davem@davemloft.net
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

perf tools: Fix use of alternatives to find JDIR

2018-11-13T19:12:17+00:00

[ Upstream commit 36b8d4628d3cc8f5a748e508cce8673bc00fc63c ]

When a build is run from something like a cron job, the user's $PATH is
rather minimal, of note, not including /usr/sbin in my own case. Because
of that, an automated rpm package build ultimately fails to find
libperf-jvmti.so, because somewhere within the build, this happens...

  /bin/sh: alternatives: command not found
  /bin/sh: alternatives: command not found
  Makefile.config:849: No openjdk development package found, please install
  JDK package, e.g. openjdk-8-jdk, java-1.8.0-openjdk-devel

...and while the build continues, libperf-jvmti.so isn't built, and
things fall down when rpm tries to find all the %files specified. Exact
same system builds everything just fine when the job is launched from a
login shell instead of a cron job, since alternatives is in $PATH, so
openjdk is actually found.

The test required to get into this section of code actually specifies
the full path, as does a block just above it, so let's do that here too.

Signed-off-by: Jarod Wilson 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: William Cohen 
Fixes: d4dfdf00d43e ("perf jvmti: Plug compilation into perf build")
Link: http://lkml.kernel.org/r/20180906221812.11167-1-jarod@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

perf evsel: Store ids for events with their own cpus perf_event__synthesize_event_update_cpus

2018-11-13T19:12:17+00:00

[ Upstream commit 4ab8455f8bd83298bf7f67ab9357e3b1cc765c7d ]

John reported crash when recording on an event under PMU with cpumask defined:

  root@localhost:~# ./perf_debug_ record -e armv8_pmuv3_0/br_mis_pred/ sleep 1
  perf: Segmentation fault
  Obtained 9 stack frames.
  ./perf_debug_() [0x4c5ef8]
  [0xffff82ba267c]
  ./perf_debug_() [0x4bc5a8]
  ./perf_debug_() [0x419550]
  ./perf_debug_() [0x41a928]
  ./perf_debug_() [0x472f58]
  ./perf_debug_() [0x473210]
  ./perf_debug_() [0x4070f4]
  /lib/aarch64-linux-gnu/libc.so.6(__libc_start_main+0xe0) [0xffff8294c8a0]
  Segmentation fault (core dumped)

We synthesize an update event that needs to touch the evsel id array, which is
not defined at that time. Fixing this by forcing the id allocation for events
with their own cpus.

Reported-by: John Garry 
Signed-off-by: Jiri Olsa 
Tested-by: John Garry 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Will Deacon 
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxarm@huawei.com
Fixes: bfd8f72c2778 ("perf record: Synthesize unit/scale/... in event update")
Link: http://lkml.kernel.org/r/20181003212052.GA32371@krava
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

perf vendor events intel: Fix wrong filter_band* values for uncore events

2018-11-13T19:12:16+00:00

[ Upstream commit 94aafb74cee0002e2f2eb6dc5376f54d5951ab4d ]

Michael reported that he could not stat following event:

  $ perf stat -e unc_p_freq_ge_1200mhz_cycles -a -- ls
  event syntax error: '..e_1200mhz_cycles'
                                    \___ value too big for format, maximum is 255
  Run 'perf list' for a list of valid events

The event is unwrapped into:

  uncore_pcu/event=0xb,filter_band0=1200/

where filter_band0 format says it's one byte only:

  # cat uncore_pcu/format/filter_band0
  config1:0-7

while JSON files specifies bigger number:

  "Filter": "filter_band0=1200",

all the filter_band* formats show 1 byte width:

  # cat uncore_pcu/format/filter_band1
  config1:8-15
  # cat uncore_pcu/format/filter_band2
  config1:16-23
  # cat uncore_pcu/format/filter_band3
  config1:24-31

The reason of the issue is that filter_band* values are supposed to be
in 100Mhz units.. it's stated in the JSON help for the events, like:

  filter_band3=XXX, with XXX in 100Mhz units

This patch divides the filter_band* values by 100, plus there's couple
of changes that actually change the number completely, like:

  -        "Filter": "edge=1,filter_band2=4000",
  +        "Filter": "edge=1,filter_band2=30",

Reported-by: Michael Petlan 
Signed-off-by: Jiri Olsa 
Acked-by: Andi Kleen 
Cc: Alexander Shishkin 
Cc: Kan Liang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20181010080339.GB15790@krava
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman