linux-stable.git/tools, 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

powerpc/selftests: Wait all threads to join

2018-11-21T08:21:58+00:00

[ Upstream commit 693b31b2fc1636f0aa7af53136d3b49f6ad9ff39 ]

Test tm-tmspr might exit before all threads stop executing, because it just
waits for the very last thread to join before proceeding/exiting.

This patch makes sure that all threads that were created will join before
proceeding/exiting.

This patch also guarantees that the amount of threads being created is equal
to thread_num.

Signed-off-by: Breno Leitao 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

selftests/powerpc: Fix ptrace tm failure

2018-11-13T19:12:52+00:00

commit 48dc0ef19044bfb69193302fbe3a834e3331b7ae upstream.

Test ptrace-tm-spd-gpr fails on current kernel (4.19) due to a segmentation
fault that happens on the child process prior to setting cptr[2] = 1. This
causes the parent process to wait forever at 'while (!pptr[2])' and the test to
be killed by the test harness framework by timeout, thus, failing.

The segmentation fault happens because of a inline assembly being
generated as:

	0x10000355c     lfs    f0, 0(0)

This is reading memory position 0x0 and causing the segmentation fault.

This code is being generated by ASM_LOAD_FPR_SINGLE_PRECISION(flt_4), where
flt_4 is passed to the inline assembly block as:

	[flt_4] "r" (&d)

Since the inline assembly 'r' constraint means any GPR, gpr0 is being
chosen, thus causing this issue when issuing a Load Floating-Point Single
instruction.

This patch simply changes the constraint to 'b', which specify that this
register will be used as base, and r0 is not allowed to be used, avoiding
this issue.

Other than that, removing flt_2 register from the input operands, since it
is not used by the inline assembly code at all.

Cc: stable@vger.kernel.org
Signed-off-by: Breno Leitao 
Acked-by: Segher Boessenkool 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

selftests/ftrace: Fix synthetic event test to delete event correctly

2018-11-13T19:12:52+00:00

commit 0d0352d8b3d6d7ca9a710b40e194cbbaeb841c88 upstream.

Fix the synthetic event test case to remove event correctly.
If redirecting command to synthetic_event file without append
mode, it cleans up all existing events and execute (parse) the
command. This means "delete event" always fails to find the
target event.

Since previous synthetic event has a bug which doesn't return
-ENOENT even if it fails to find the deleting event, this test
passed. But fixing that bug, this test fails because this test
itself has a bug.

This fixes that bug by trying to delete event right after
adding an event, and use append mode redirection ('>>') instead
of normal redirection ('>').

Link: http://lkml.kernel.org/r/154013452832.25576.2305459545429386517.stgit@devbox

Acked-by: Shuah Khan 
Acked-by: Tom Zanussi 
Tested-by: Tom Zanussi 
Cc: Tom Zanussi 
Cc: Tom Zanussi 
Cc: Rajvi Jingar 
Cc: Shuah Khan 
Cc: stable@vger.kernel.org
Fixes: f06eec4d0f2c ('selftests: ftrace: Add inter-event hist triggers testcases')
Signed-off-by: Masami Hiramatsu 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Greg Kroah-Hartman

cpupower: Fix AMD Family 0x17 msr_pstate size

2018-11-13T19:12:35+00:00

[ Upstream commit 8c22e2f695920ebd94f9a53bcf2a65eb36d4dba1 ]

The msr_pstate data is only 63 bits long and should be 64 bits.

Add in the missing bit from res1 for AMD Family 0x17.

Reference: https://www.amd.com/system/files/TechDocs/54945_PPR_Family_17h_Models_00h-0Fh.pdf, page 138.

Signed-off-by: Prarit Bhargava 
Cc: Shuah Khan 
Cc: Stafford Horne 
Signed-off-by: Shuah Khan (Samsung OSG) 
Signed-off-by: Sasha Levin 
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

cpupower: Fix coredump on VMWare

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

[ Upstream commit f69ffc5d3db8f1f03fd6d1df5930f9a1fbd787b6 ]

cpupower crashes on VMWare guests.  The guests have the AMD PStateDef MSR
(0xC0010064 + state number) set to zero.  As a result fid and did are zero
and the crash occurs because of a divide by zero (cof = fid/did).  This
can be prevented by checking the enable bit in the PStateDef MSR before
calculating cof.  By doing this the value of pstate[i] remains zero and
the value can be tested before displaying the active Pstates.

Check the enable bit in the PstateDef register for all supported families
and only print out enabled Pstates.

Signed-off-by: Prarit Bhargava 
Cc: Shuah Khan 
Cc: Stafford Horne 
Signed-off-by: Shuah Khan (Samsung OSG) 
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