Add a shell script to check that the call-graphs generated using frame
pointers (--call-graph fp) are complete and not missing leaf functions:
| $ perf test 88 -v
| 88: Check Arm64 callgraphs are complete in fp mode :
| --- start ---
| test child forked, pid 8734
| + Compiling test program (/tmp/test_program.Cz3yL)...
| + Recording (PID=8749)...
| + Stopping perf-record...
| test_program.Cz
| 728 leaf
| 753 parent
| 76c main
| test child finished with 0
| ---- end ----
| Check Arm SPE callgraphs are complete in fp mode: Ok
It's supposed to work with both unwinders:
| $ make # for libunwind (default)
| $ make NO_LIBUNWIND=1 # for libdw
Tester notes:
Ran it on N1SDP and it passes, and it fails if b9f6fbb3b2 ("perf
arm64: Inject missing frames when using 'perf record --call-graph=fp'")
isn't applied.
Fixes: b9f6fbb3b2 ("perf arm64: Inject missing frames when using 'perf record --call-graph=fp'")
Suggested-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: James Clark <james.clark@arm.com>
Tested-by: James Clark <james.clark@arm.com>
Signed-off-by: German Gomez <german.gomez@arm.com>
Cc: Alexandre Truong <alexandre.truong@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20220316172015.98000-1-german.gomez@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It builds a test program and use it to verify pipe behavior with perf
record, inject and report.
$ perf test pipe -v
80: perf pipe recording and injection test :
--- start ---
test child forked, pid 1109301
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
1109315 1109315 -1 |test.file.MGNff
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
99.99% test.file.MGNff test.file.MGNffM [.] noploop
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
99.99% test.file.MGNff test.file.MGNffM [.] noploop
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.153 MB /tmp/perf.data.dmsnlx (3995 samples) ]
99.99% test.file.MGNff test.file.MGNffM [.] noploop
test child finished with 0
---- end ----
perf pipe recording and injection test: Ok
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210719223153.1618812-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When executing the daemon test on Arm64 and x86 with Debian (Buster)
distro, both skip the test case with the log:
# ./perf test -v 76
76: daemon operations :
--- start ---
test child forked, pid 11687
test daemon list
trap: SIGINT: bad trap
./tests/shell/daemon.sh: 173: local: cpu-clock: bad variable name
test child finished with -2
---- end ----
daemon operations: Skip
So the error happens for the variable expansion when use local variable
in the shell script. Since Debian Buster uses dash but not bash as
non-interactive shell, when execute the daemon testing, it hits a known
issue for dash which was reported [1].
To resolve this issue, one option is to add double quotes for all local
variables assignment, so need to change the code from:
local line=`perf daemon --config ${config} -x: | head -2 | tail -1`
... to:
local line="`perf daemon --config ${config} -x: | head -2 | tail -1`"
But the testing script has bunch of local variables, this leads to big
changes for whole script.
On the other hand, the testing script asks to use the "local" feature
which is bash-specific, so this patch explicitly uses "#!/bin/bash" to
ensure running the script with bash.
After:
# ./perf test -v 76
76: daemon operations :
--- start ---
test child forked, pid 11329
test daemon list
test daemon reconfig
test daemon stop
test daemon signal
signal 12 sent to session 'test [11596]'
signal 12 sent to session 'test [11596]'
test daemon ping
test daemon lock
test child finished with 0
---- end ----
daemon operations: Ok
[1] https://bugs.launchpad.net/ubuntu/+source/dash/+bug/139097
Fixes: 2291bb915b ("perf tests: Add daemon 'list' command test")
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210320104554.529213-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a test to compare the output of perf-stat with and without option
--bpf-counters. If the difference is more than 10%, the test is considered
as failed.
Committer testing:
# perf test bpf-counters
86: perf stat --bpf-counters test : Ok
# perf test -v bpf-counters
86: perf stat --bpf-counters test :
--- start ---
test child forked, pid 2433339
test child finished with 0
---- end ----
perf stat --bpf-counters test: Ok
#
Signed-off-by: Song Liu <songliubraving@fb.com>
Requested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/EC00E37D-8587-4662-8E30-7AD5F874FA84@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the fixes sent for v5.12 and continue development based on
v5.12-rc2, i.e. without the swap on file bug.
This also gets a slightly newer and better tools/perf/arch/arm/util/cs-etm.c
patch version, using the BIT() macro, that had already been slated to
v5.13 but ended up going to v5.12-rc1 on an older version.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The CoreSight testing contains sub cases, e.g. every CPU iterates the
possible conntected sinks and tests the paths between the associated ETM
with the found sink. Besides the per-thread testing, it also contains
system wide testing and snapshot testing.
To easier observe results for the sub cases, this patch introduces a new
function arm_cs_report(), it outputs the result as "PASS" or "FAIL" for
every sub case; and it records the error in the variable "glb_err" which
is used as the final return value when exits the testing.
Before:
# perf test 73 -v
73: Check Arm CoreSight trace data recording and synthesized samples:
--- start ---
test child forked, pid 17423
Recording trace (only user mode) with path: CPU0 => tmc_etf0
Looking at perf.data file for dumping branch samples:
Looking at perf.data file for reporting branch samples:
Looking at perf.data file for instruction samples:
Recording trace (only user mode) with path: CPU0 => tmc_etr0
Looking at perf.data file for dumping branch samples:
Looking at perf.data file for reporting branch samples:
Looking at perf.data file for instruction samples:
[...]
After:
# perf test 73 -v
73: Check Arm CoreSight trace data recording and synthesized samples:
--- start ---
test child forked, pid 17423
Recording trace (only user mode) with path: CPU0 => tmc_etf0
Looking at perf.data file for dumping branch samples:
Looking at perf.data file for reporting branch samples:
Looking at perf.data file for instruction samples:
CoreSight path testing (CPU0 -> tmc_etf0): PASS
Recording trace (only user mode) with path: CPU0 => tmc_etr0
Looking at perf.data file for dumping branch samples:
Looking at perf.data file for reporting branch samples:
Looking at perf.data file for instruction samples:
CoreSight path testing (CPU0 -> tmc_etr0): PASS
[...]
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Basil Eljuse <basil.eljuse@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: http://lore.kernel.org/lkml/20210215115944.535986-3-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a test for the perf daemon 'signal' command. The test sends a signal
to configured sessions and verifies the perf data files were generated
accordingly.
Committer testing:
[root@five ~]# perf test daemon
76: daemon operations : Ok
[root@five ~]# perf test -v daemon
76: daemon operations :
--- start ---
test child forked, pid 790017
test daemon list
test daemon reconfig
test daemon stop
test daemon signal
signal 12 sent to session 'test [790268]'
signal 12 sent to session 'test [790268]'
test child finished with 0
---- end ----
daemon operations: Ok
[root@five ~]#
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Budankov <abudankov@huawei.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20210208200908.1019149-23-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a test for daemon reconfiguration. The test changes the
configuration file and checks that the session is changed properly.
Committer testing:
[root@five ~]# perf test daemon
76: daemon operations : Ok
[root@five ~]# time perf test daemon
76: daemon operations : Ok
real 0m6.055s
user 0m0.174s
sys 0m0.147s
[root@five ~]# time perf test -v daemon
76: daemon operations :
--- start ---
test child forked, pid 786863
test daemon list
test daemon reconfig
test child finished with 0
---- end ----
daemon operations: Ok
real 0m6.127s
user 0m0.222s
sys 0m0.165s
[root@five ~]#
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Budankov <abudankov@huawei.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20210208200908.1019149-21-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It was using some bash-specific features and failed to parse when
running with a different shell like below:
root@kbl-ppc:~/kbl-ws/perf-dev/lck-9077/acme.tmp/tools/perf# ./perf test 83 -vv
83: perf stat metrics (shadow stat) test :
--- start ---
test child forked, pid 3922
./tests/shell/stat+shadow_stat.sh: 19: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 24: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 30: ./tests/shell/stat+shadow_stat.sh: [[: not found
(standard_in) 2: syntax error
./tests/shell/stat+shadow_stat.sh: 36: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 19: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 24: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 30: ./tests/shell/stat+shadow_stat.sh: [[: not found
(standard_in) 2: syntax error
./tests/shell/stat+shadow_stat.sh: 36: ./tests/shell/stat+shadow_stat.sh: [[: not found
./tests/shell/stat+shadow_stat.sh: 45: ./tests/shell/stat+shadow_stat.sh: declare: not found
test child finished with -1
---- end ----
perf stat metrics (shadow stat) test: FAILED!
Reported-by: Jin Yao <yao.jin@linux.intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Laight <david.laight@aculab.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210114050609.1258820-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It calculates IPC from the cycles and instruction counts and compares it
with the shadow stat for both global aggregation (default) and no
aggregation mode.
$ perf stat -a -A -e cycles,instructions sleep 1
Performance counter stats for 'system wide':
CPU0 39,580,880 cycles
CPU1 45,426,945 cycles
CPU2 31,151,685 cycles
CPU3 55,167,421 cycles
CPU0 17,073,564 instructions # 0.43 insn per cycle
CPU1 34,955,764 instructions # 0.77 insn per cycle
CPU2 15,688,459 instructions # 0.50 insn per cycle
CPU3 34,699,217 instructions # 0.63 insn per cycle
1.003275495 seconds time elapsed
In this example, the 'insn per cycle' should be matched to the number
for each cpu. For CPU2, 0.50 = 15,688,459 / 31,151,685 .
Committer testing:
# perf test shadow
78: perf stat metrics (shadow stat) test : Ok
#
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201127041404.390276-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a test for the build id cache that adds a binary with sha1 and md5
build ids and verifies it's added properly.
The test updates build id cache with 'perf record' and 'perf buildid-cache -a'.
Committer testing:
# perf test "build id"
82: build id cache operations : Ok
#
# perf test -v "build id"
82: build id cache operations :
--- start ---
test child forked, pid 447218
test binaries: /tmp/perf.ex.SHA1.B8I /tmp/perf.ex.MD5.7Nv
Adding d1abc1eb7568358cf23c959566f23462461834d1 /tmp/perf.ex.SHA1.B8I: Ok
build id: d1abc1eb7568358cf23c959566f23462461834d1
link: /tmp/perf.debug.sS2/.build-id/d1/abc1eb7568358cf23c959566f23462461834d1
file: /tmp/perf.debug.sS2/.build-id/d1/../../tmp/perf.ex.SHA1.B8I/d1abc1eb7568358cf23c959566f23462461834d1/elf
OK for /tmp/perf.ex.SHA1.B8I
Adding a50e350e97c43b4708d09bcd85ebfff7 /tmp/perf.ex.MD5.7Nv: Ok
build id: a50e350e97c43b4708d09bcd85ebfff7
link: /tmp/perf.debug.IuW/.build-id/a5/0e350e97c43b4708d09bcd85ebfff7
file: /tmp/perf.debug.IuW/.build-id/a5/../../tmp/perf.ex.MD5.7Nv/a50e350e97c43b4708d09bcd85ebfff7/elf
OK for /tmp/perf.ex.MD5.7Nv
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.034 MB /tmp/perf.data.xrH ]
build id: d1abc1eb7568358cf23c959566f23462461834d1
link: /tmp/perf.debug.eGR/.build-id/d1/abc1eb7568358cf23c959566f23462461834d1
file: /tmp/perf.debug.eGR/.build-id/d1/../../tmp/perf.ex.SHA1.B8I/d1abc1eb7568358cf23c959566f23462461834d1/elf
OK for /tmp/perf.ex.SHA1.B8I
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.034 MB /tmp/perf.data.cbE ]
build id: a50e350e97c43b4708d09bcd85ebfff7
link: /tmp/perf.debug.82t/.build-id/a5/0e350e97c43b4708d09bcd85ebfff7
file: /tmp/perf.debug.82t/.build-id/a5/../../tmp/perf.ex.MD5.7Nv/a50e350e97c43b4708d09bcd85ebfff7/elf
OK for /tmp/perf.ex.MD5.7Nv
test child finished with 0
---- end ----
build id cache operations: Ok
#
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/r/20201013192441.1299447-10-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We need a simple method to test Perf with ARM CoreSight drivers, this
could be used for smoke testing when new patch is coming for perf or
CoreSight drivers, and we also can use the test to confirm if the
CoreSight has been enabled successfully on new platforms.
This patch introduces the shell script test_arm_coresight.sh which is
under the 'pert test' framework. This script provides three testing
scenarios:
Test scenario 1: traverse all possible paths between source and sink
For traversing possible paths, simply to say, the testing rationale is
source oriented testing, it traverses every source (now only refers to
ETM device) and test its all possible sinks. To search the complete
paths from one specific source to its sinks, this patch relies on the
sysfs '/sys/bus/coresight/devices/devX/out:Y' for depth-first search
(DFS) for iteration connected device nodes, if the output device is
detected as a sink device (the script will exclude TPIU device which can
not be supported for perf PMU), then it will test trace data recording
and decoding for it.
The script runs three output testings for every trace data:
- Test branch samples dumping with 'perf script' command;
- Test branch samples reporting with 'perf report' command;
- Use option '--itrace=i1000i' to insert synthesized instructions events
and the script will check if perf can output the percentage value
successfully based on the instruction samples.
Test scenario 2: system-wide test
For system-wide testing, it passes option '-a' to perf tool to enable
tracing on all CPUs, so it's hard to say which program will be traced.
But perf tool itself contributes much overload in this case, so it will
parse trace data and check if process 'perf' can be detected or not.
Test scenario 3: snapshot mode test.
For snapshot mode testing, it uses 'dd' command to launch a long running
program, so this can give chance to send signal -USR2; it will check the
captured trace data contains 'dd' related thread info or not.
If any test fails, it will report failure and directly exit with error.
This test will be only applied on a platform with PMU event 'cs_etm//',
otherwise will skip the testing.
Below is detailed usage for it:
# cd $linux/tools/perf -> This is important so can use shell script
# perf test list
[...]
70: probe libc's inet_pton & backtrace it with ping
71: Check Arm CoreSight trace data recording and synthesized samples
72: Check open filename arg using perf trace + vfs_getname
73: Zstd perf.data compression/decompression
74: Add vfs_getname probe to get syscall args filenames
75: Use vfs_getname probe to get syscall args filenames
# perf test 71
71: Check Arm CoreSight trace data recording and branch samples: Ok
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200907130154.9601-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Sometimes when adding a kprobe by perf, it results in multiple probe
points, such as the following:
# ./perf probe -l
probe:vfs_getname (on getname_flags:73@fs/namei.c with pathname)
probe:vfs_getname_1 (on getname_flags:73@fs/namei.c with pathname)
probe:vfs_getname_2 (on getname_flags:73@fs/namei.c with pathname)
# cat /sys/kernel/debug/tracing/kprobe_events
p:probe/vfs_getname _text+5501804 pathname=+0(+0(%gpr31)):string
p:probe/vfs_getname_1 _text+5505388 pathname=+0(+0(%gpr31)):string
p:probe/vfs_getname_2 _text+5508396 pathname=+0(+0(%gpr31)):string
In this test, we need to record all of them and expect any of them in
the perf-script output, since it's not clear which one will be used for
the desired syscall:
# perf stat -e probe:vfs_getname\* -- touch /tmp/nic
Performance counter stats for 'touch /tmp/nic':
31 probe:vfs_getname_2
0 probe:vfs_getname_1
1 probe:vfs_getname
0.001421826 seconds time elapsed
0.001506000 seconds user
0.000000000 seconds sys
If the test relies only on probe:vfs_getname, it might easily miss the
relevant data.
Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
LPU-Reference: 20200722135845.29958-1-mpetlan@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 5aa98879ef ("s390/cpum_sf: prohibit callchain data collection")
prohibits call graph sampling for hardware events on s390. The
information recorded is out of context and does not match.
On s390 this commit now breaks test case 68 Zstd perf.data
compression/decompression.
Therefore omit call graph sampling on s390 in this test.
Output before:
[root@t35lp46 perf]# ./perf test -Fv 68
68: Zstd perf.data compression/decompression :
--- start ---
Collecting compressed record file:
Error:
cycles: PMU Hardware doesn't support sampling/overflow-interrupts.
Try 'perf stat'
---- end ----
Zstd perf.data compression/decompression: FAILED!
[root@t35lp46 perf]#
Output after:
[root@t35lp46 perf]# ./perf test -Fv 68
68: Zstd perf.data compression/decompression :
--- start ---
Collecting compressed record file:
500+0 records in
500+0 records out
256000 bytes (256 kB, 250 KiB) copied, 0.00615638 s, 41.6 MB/s
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.004 MB /tmp/perf.data.X3M,
compressed (original 0.002 MB, ratio is 3.609) ]
Checking compressed events stats:
# compressed : Zstd, level = 1, ratio = 4
COMPRESSED events: 1
2ELIFREPh---- end ----
Zstd perf.data compression/decompression: Ok
[root@t35lp46 perf]#
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200729135314.91281-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This test places a kprobe to function getname_flags() in the kernel
which has the following prototype:
struct filename *getname_flags(const char __user *filename, int flags, int *empty)
The 'filename' argument points to a filename located in user space memory.
Looking at commit 88903c4643 ("tracing/probe: Add ustring type for
user-space string") the kprobe should indicate that user space memory is
accessed.
Output before:
[root@m35lp76 perf]# ./perf test 66 67
66: Use vfs_getname probe to get syscall args filenames : FAILED!
67: Check open filename arg using perf trace + vfs_getname: FAILED!
[root@m35lp76 perf]#
Output after:
[root@m35lp76 perf]# ./perf test 66 67
66: Use vfs_getname probe to get syscall args filenames : Ok
67: Check open filename arg using perf trace + vfs_getname: Ok
[root@m35lp76 perf]#
Comments from Masami Hiramatsu:
This bug doesn't happen on x86 or other archs on which user address
space and kernel address space is the same. On some arches (ppc64 in
this case?) user address space is partially or completely the same as
kernel address space.
(Yes, they switch the world when running into the kernel) In this case,
we need to use different data access functions for each space.
That is why I introduced the "ustring" type for kprobe events.
As far as I can see, Thomas's patch is sane. Thomas, could you show us
your result on your test environment?
Comments from Thomas Richter:
Test results for s/390 included above.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200217102111.61137-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>