linux-stable.git/tools/perf/util, branch v6.2

perf buildid-cache: Fix the file mode with copyfile() while adding file to build-id cache

2023-01-18T13:39:16+00:00

The test "build id cache operations" fails on powerpc as below:

	Adding 5a0fd882b53084224ba47b624c55a469 ./tests/shell/../pe-file.exe: Ok
	build id: 5a0fd882b53084224ba47b624c55a469
	link: /tmp/perf.debug.ZTu/.build-id/5a/0fd882b53084224ba47b624c55a469
	file: /tmp/perf.debug.ZTu/.build-id/5a/../../root/linux/tools/perf/tests/pe-file.exe/5a0fd882b53084224ba47b624c55a469/elf
	failed: file /tmp/perf.debug.ZTu/.build-id/5a/../../root/linux/tools/perf/tests/pe-file.exe/5a0fd882b53084224ba47b624c55a469/elf does not exist
	test child finished with -1
	---- end ----
	build id cache operations: FAILED!

The failing test is when trying to add pe-file.exe to build id cache.

'perf buildid-cache' can be used to add/remove/manage files from the
build-id cache. "-a" option is used to add a file to the build-id cache.

Simple command to do so for a PE exe file:

  # ls -ltr tests/pe-file.exe
  -rw-r--r--. 1 root root 75595 Jan 10 23:35 tests/pe-file.exe

  The file is in home directory.

  # mkdir  /tmp/perf.debug.TeY1
  # perf --buildid-dir /tmp/perf.debug.TeY1 buildid-cache -v -a tests/pe-file.exe

The above will create ".build-id" folder in build id directory, which is
/tmp/perf.debug.TeY1. Also adds file to this folder under build id.
Example:

  # ls -ltr /tmp/perf.debug.TeY1/.build-id/5a/0fd882b53084224ba47b624c55a469/
  total 76
  -rw-r--r--. 1 root root     0 Jan 11 00:38 probes
  -rwxr-xr-x. 1 root root 75595 Jan 11 00:38 elf

We can see in the results that file mode for original file and file in
build id directory is different. ie, build id file has executable
permission whereas original file doesn’t have.

The code path and function (build_id_cache__add  to add a file to the
cache is in "util/build-id.c". In build_id_cache__add() function, it
first attempts to link the original file to destination cache folder.

If linking the file fails (which can happen if the destination and
source is on a different mount points), it will copy the file to
destination.  Here copyfile() routine explicitly uses mode as "755" and
hence file in the destination will have executable permission.

Code snippet:

 if (link(realname, filename) && errno != EEXIST && copyfile(name, filename))

strace logs:

	172285 link("/home//linux/tools/perf/tests/pe-file.exe", "/tmp/perf.debug.TeY1/home//linux/tools/perf/tests/pe-file.exe/5a0fd882b53084224ba47b624c55a469/elf") = -1 EXDEV (Invalid cross-device link)
	172285 newfstatat(AT_FDCWD, "tests/pe-file.exe", {st_mode=S_IFREG|0644, st_size=75595, ...}, 0) = 0
	172285 openat(AT_FDCWD, "/tmp/perf.debug.TeY1/home//linux/tools/perf/tests/pe-file.exe/5a0fd882b53084224ba47b624c55a469/.elf.KbAnsl", O_RDWR|O_CREAT|O_EXCL, 0600) = 3
	172285 fchmod(3, 0755)                  = 0
	172285 openat(AT_FDCWD, "tests/pe-file.exe", O_RDONLY) = 4
	172285 mmap(NULL, 75595, PROT_READ, MAP_PRIVATE, 4, 0) = 0x7fffa5cd0000
	172285 pwrite64(3, "MZ\220\0\3\0\0\0\4\0\0\0\377\377\0\0\270\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 75595, 0) = 75595

Whereas if the link succeeds, it succeeds in the first attempt itself
and the file in the build-id dir will have same permission as original
file.

Example, above uses /tmp. Instead if we use "--buildid-dir /home/build",
linking will work here since mount points are same. Hence the
destination file will not have executable permission.

Since the testcase "tests/shell/buildid.sh" always looks for executable
file, test fails in powerpc environment when test is run from /root.

The patch adds a change in build_id_cache__add() to use copyfile_mode()
which also passes the file’s original mode as argument. This way the
destination file mode also will be same as original file.

Signed-off-by: Athira Jajeev 
Cc: Andi Kleen 
Cc: Disha Goel 
Cc: Ian Rogers 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Kajol Jain 
Cc: Madhavan Srinivasan 
Cc: Michael Ellerman 
Cc: Nageswara R Sastry 
Cc: Namhyung Kim 
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lore.kernel.org/r/20230116050131.17221-1-atrajeev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo

perf expr: Prevent normalize() from reading into undefined memory in the expression lexer

2023-01-18T13:33:00+00:00

The current implementation does not account for a trailing backslash
followed by a null-byte.

If a null-byte is encountered following a backslash, normalize() will
continue reading (and potentially writing) into garbage memory ignoring
the EOS null-byte.

Signed-off-by: Sohom Datta 
Acked-by: Ian Rogers 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Ingo Molnar 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20221204105836.1012885-1-sohomdatta1+git@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

perf auxtrace: Fix address filter duplicate symbol selection

2023-01-11T17:03:44+00:00

When a match has been made to the nth duplicate symbol, return
success not error.

Example:

  Before:

    $ cat file.c
    cat: file.c: No such file or directory
    $ cat file1.c
    #include 

    static void func(void)
    {
            printf("First func\n");
    }

    void other(void);

    int main()
    {
            func();
            other();
            return 0;
    }
    $ cat file2.c
    #include 

    static void func(void)
    {
            printf("Second func\n");
    }

    void other(void)
    {
            func();
    }

    $ gcc -Wall -Wextra -o test file1.c file2.c
    $ perf record -e intel_pt//u --filter 'filter func @ ./test' -- ./test
    Multiple symbols with name 'func'
    #1      0x1149  l       func
                    which is near           main
    #2      0x1179  l       func
                    which is near           other
    Disambiguate symbol name by inserting #n after the name e.g. func #2
    Or select a global symbol by inserting #0 or #g or #G
    Failed to parse address filter: 'filter func @ ./test'
    Filter format is: filter|start|stop|tracestop  [/ ] [@]
    Where multiple filters are separated by space or comma.
    $ perf record -e intel_pt//u --filter 'filter func #2 @ ./test' -- ./test
    Failed to parse address filter: 'filter func #2 @ ./test'
    Filter format is: filter|start|stop|tracestop  [/ ] [@]
    Where multiple filters are separated by space or comma.

  After:

    $ perf record -e intel_pt//u --filter 'filter func #2 @ ./test' -- ./test
    First func
    Second func
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.016 MB perf.data ]
    $ perf script --itrace=b -Ftime,flags,ip,sym,addr --ns
    1231062.526977619:   tr strt                               0 [unknown] =>     558495708179 func
    1231062.526977619:   tr end  call               558495708188 func =>     558495708050 _init
    1231062.526979286:   tr strt                               0 [unknown] =>     55849570818d func
    1231062.526979286:   tr end  return             55849570818f func =>     55849570819d other

Fixes: 1b36c03e356936d6 ("perf record: Add support for using symbols in address filters")
Reported-by: Dmitrii Dolgov <9erthalion6@gmail.com>
Signed-off-by: Adrian Hunter 
Tested-by: Dmitry Dolgov <9erthalion6@gmail.com>
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230110185659.15979-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Properly guard libbpf includes

2023-01-10T13:51:39+00:00

Including libbpf header files should be guarded by HAVE_LIBBPF_SUPPORT.
In bpf_counter.h, move the skeleton utilities under HAVE_BPF_SKEL.

Fixes: d6a735ef3277c45f ("perf bpf_counter: Move common functions to bpf_counter.h")
Reported-by: Mike Leach 
Signed-off-by: Ian Rogers 
Tested-by: Arnaldo Carvalho de Melo 
Tested-by: Jiri Olsa 
Tested-by: Mike Leach 
Cc: Alexander Shishkin 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20230105172243.7238-1-mike.leach@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix build on uClibc systems by adding missing sys/types.h include

2023-01-04T19:44:01+00:00

Not all libc implementations define ssize_t as part of stdio.h like
glibc does since the standard only requires this type to be defined by
unistd.h and sys/types.h. For this reason the perf build is currently
broken for toolchains based on uClibc, for instance.

Include sys/types.h explicitly to fix that.

Committer notes:

In addition, in the past this worked in uClibc test systems as there was
another way to get to sys/types.h that got removed in that cset:

  tools/perf/util/trace-event.h
    /usr/include/traceevent/event_parse.h # This got removed from util/trace-event.h in 378ef0f5d9d7f465
      /usr/include/regex.h
        /usr/include/sys/types.h
          typedef __ssize_t ssize_t;

So the size_t that is used in tools/perf/util/trace-event.h was being
obtained indirectly, by chance.

Fixes: 378ef0f5d9d7f465 ("perf build: Use libtraceevent from the system")
Signed-off-by: Jesus Sanchez-Palencia 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/20230104193414.606905-1-jesussanp@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Fix handling of --for-each-cgroup with --bpf-counters to match non BPF mode

2023-01-04T14:11:41+00:00

The --for-each-cgroup can have the same cgroup multiple times, but this
confuses BPF counters (since they have the same cgroup id), making only
the last cgroup events to be counted.

Let's check the cgroup name before adding a new entry to the cgroups
list.

Before:

  $ sudo ./perf stat -a --bpf-counters --for-each-cgroup /,/ sleep 1

   Performance counter stats for 'system wide':

        msec cpu-clock                        /
             context-switches                 /
             cpu-migrations                   /
             page-faults                      /
             cycles                           /
             instructions                     /
             branches                         /
             branch-misses                    /
            8,016.04 msec cpu-clock                        /                #    7.998 CPUs utilized
               6,152      context-switches                 /                #  767.461 /sec
                 250      cpu-migrations                   /                #   31.187 /sec
                 442      page-faults                      /                #   55.139 /sec
         613,111,487      cycles                           /                #    0.076 GHz
         280,599,604      instructions                     /                #    0.46  insn per cycle
          57,692,724      branches                         /                #    7.197 M/sec
           3,385,168      branch-misses                    /                #    5.87% of all branches

         1.002220125 seconds time elapsed

After it becomes similar to the non-BPF mode:

  $ sudo ./perf stat -a --bpf-counters --for-each-cgroup /,/  sleep 1

   Performance counter stats for 'system wide':

            8,013.38 msec cpu-clock                        /                #    7.998 CPUs utilized
               6,859      context-switches                 /                #  855.944 /sec
                 334      cpu-migrations                   /                #   41.680 /sec
                 345      page-faults                      /                #   43.053 /sec
         782,326,119      cycles                           /                #    0.098 GHz
         471,645,724      instructions                     /                #    0.60  insn per cycle
          94,963,430      branches                         /                #   11.851 M/sec
           3,685,511      branch-misses                    /                #    3.88% of all branches

         1.001864539 seconds time elapsed

Committer notes:

As a reminder, to test with BPF counters one has to use BUILD_BPF_SKEL=1
in the make command line and have clang/llvm installed when building
perf, otherwise the --bpf-counters option will not be available:

  # perf stat -a --bpf-counters --for-each-cgroup /,/ sleep 1
  Error: unknown option `bpf-counters'

   Usage: perf stat [] []

      -a, --all-cpus        system-wide collection from all CPUs
  
  #

Fixes: bb1c15b60b981d10 ("perf stat: Support regex pattern in --for-each-cgroup")
Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: bpf@vger.kernel.org
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Song Liu 
Link: https://lore.kernel.org/r/20230104064402.1551516-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Fix handling of unsupported cgroup events when using BPF counters

2023-01-04T13:52:07+00:00

When --for-each-cgroup option is used, it fails when any of events is
not supported and exits immediately.  This is not how 'perf stat'
handles unsupported events.

Let's ignore the failure and proceed with others so that the output is
similar to when BPF counters are not used:

Before:

  $ sudo ./perf stat -a --bpf-counters -e L1-icache-loads,L1-dcache-loads --for-each-cgroup system.slice,user.slice sleep 1
  Failed to open first cgroup events
  $

After it shows output similat to when --bpf-counters isn't specified:

  $ sudo ./perf stat -a --bpf-counters -e L1-icache-loads,L1-dcache-loads --for-each-cgroup system.slice,user.slice sleep 1

   Performance counter stats for 'system wide':

           L1-icache-loads                  system.slice
          29,892,418      L1-dcache-loads                  system.slice
           L1-icache-loads                  user.slice
          52,497,220      L1-dcache-loads                  user.slice
  $

Fixes: 944138f048f7d759 ("perf stat: Enable BPF counter with --for-each-cgroup")
Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Song Liu 
Link: https://lore.kernel.org/r/20230104064402.1551516-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix segfault when trying to process tracepoints in perf.data and not linked with libtraceevent

2023-01-02T16:45:19+00:00

When we have a perf.data file with tracepoints, such as:

  # perf evlist -f
  probe_perf:lzma_decompress_to_file
  # Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events
  #

We end up segfaulting when using perf built with NO_LIBTRACEEVENT=1 by
trying to find an evsel with a NULL 'event_name' variable:

  (gdb) run report --stdio -f
  Starting program: /root/bin/perf report --stdio -f

  Program received signal SIGSEGV, Segmentation fault.
  0x000000000055219d in find_evsel (evlist=0xfda7b0, event_name=0x0) at util/sort.c:2830
  warning: Source file is more recent than executable.
  2830		if (event_name[0] == '%') {
  Missing separate debuginfos, use: dnf debuginfo-install bzip2-libs-1.0.8-11.fc36.x86_64 cyrus-sasl-lib-2.1.27-18.fc36.x86_64 elfutils-debuginfod-client-0.188-3.fc36.x86_64 elfutils-libelf-0.188-3.fc36.x86_64 elfutils-libs-0.188-3.fc36.x86_64 glibc-2.35-20.fc36.x86_64 keyutils-libs-1.6.1-4.fc36.x86_64 krb5-libs-1.19.2-12.fc36.x86_64 libbrotli-1.0.9-7.fc36.x86_64 libcap-2.48-4.fc36.x86_64 libcom_err-1.46.5-2.fc36.x86_64 libcurl-7.82.0-12.fc36.x86_64 libevent-2.1.12-6.fc36.x86_64 libgcc-12.2.1-4.fc36.x86_64 libidn2-2.3.4-1.fc36.x86_64 libnghttp2-1.51.0-1.fc36.x86_64 libpsl-0.21.1-5.fc36.x86_64 libselinux-3.3-4.fc36.x86_64 libssh-0.9.6-4.fc36.x86_64 libstdc++-12.2.1-4.fc36.x86_64 libunistring-1.0-1.fc36.x86_64 libunwind-1.6.2-2.fc36.x86_64 libxcrypt-4.4.33-4.fc36.x86_64 libzstd-1.5.2-2.fc36.x86_64 numactl-libs-2.0.14-5.fc36.x86_64 opencsd-1.2.0-1.fc36.x86_64 openldap-2.6.3-1.fc36.x86_64 openssl-libs-3.0.5-2.fc36.x86_64 slang-2.3.2-11.fc36.x86_64 xz-libs-5.2.5-9.fc36.x86_64 zlib-1.2.11-33.fc36.x86_64
  (gdb) bt
  #0  0x000000000055219d in find_evsel (evlist=0xfda7b0, event_name=0x0) at util/sort.c:2830
  #1  0x0000000000552416 in add_dynamic_entry (evlist=0xfda7b0, tok=0xffb6eb "trace", level=2) at util/sort.c:2976
  #2  0x0000000000552d26 in sort_dimension__add (list=0xf93e00 , tok=0xffb6eb "trace", evlist=0xfda7b0, level=2) at util/sort.c:3193
  #3  0x0000000000552e1c in setup_sort_list (list=0xf93e00 , str=0xffb6eb "trace", evlist=0xfda7b0) at util/sort.c:3227
  #4  0x00000000005532fa in __setup_sorting (evlist=0xfda7b0) at util/sort.c:3381
  #5  0x0000000000553cdc in setup_sorting (evlist=0xfda7b0) at util/sort.c:3608
  #6  0x000000000042eb9f in cmd_report (argc=0, argv=0x7fffffffe470) at builtin-report.c:1596
  #7  0x00000000004aee7e in run_builtin (p=0xf64ca0 , argc=3, argv=0x7fffffffe470) at perf.c:330
  #8  0x00000000004af0f2 in handle_internal_command (argc=3, argv=0x7fffffffe470) at perf.c:384
  #9  0x00000000004af241 in run_argv (argcp=0x7fffffffe29c, argv=0x7fffffffe290) at perf.c:428
  #10 0x00000000004af5fc in main (argc=3, argv=0x7fffffffe470) at perf.c:562
  (gdb)

So check if we have tracepoint events in add_dynamic_entry() and bail
out instead:

  # perf report --stdio -f
  This perf binary isn't linked with libtraceevent, can't process probe_perf:lzma_decompress_to_file
  Error:
  Unknown --sort key: `trace'
  #

Fixes: 378ef0f5d9d7f465 ("perf build: Use libtraceevent from the system")
Acked-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/Y7MDb7kRaHZB6APC@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Don't include signature in version strings

2023-01-02T15:34:06+00:00

This explodes the build if HEAD is signed, since the generated version
is gpg: Signature made Mon 26 Dec 2022 20:34:48 CET, then a few more
lines, then the SHA.

Signed-off-by: Ahelenia Ziemiańska 
Acked-by: Namhyung Kim 
Cc: Alexander Shishkin 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/7c9637711271f50ec2341fb8a7c29585335dab04.1672174189.git.nabijaczleweli@nabijaczleweli.xyz
Signed-off-by: Arnaldo Carvalho de Melo

perf help: Use HAVE_LIBTRACEEVENT to filter out unsupported commands

2023-01-02T14:51:53+00:00

Commands such as kmem, kwork, lock, sched, trace and timechart depend on
libtraceevent, these commands need to be isolated using HAVE_LIBTRACEEVENT
macro when cmdlist generation.

The output of the generate-cmdlist.sh script is as follows:

  # ./util/generate-cmdlist.sh
  /* Automatically generated by ./util/generate-cmdlist.sh */
  struct cmdname_help
  {
      char name[16];
      char help[80];
  };

  static struct cmdname_help common_cmds[] = {
    {"annotate", "Read perf.data (created by perf record) and display annotated code"},
    {"archive", "Create archive with object files with build-ids found in perf.data file"},
    {"bench", "General framework for benchmark suites"},
    {"buildid-cache", "Manage build-id cache."},
    {"buildid-list", "List the buildids in a perf.data file"},
    {"c2c", "Shared Data C2C/HITM Analyzer."},
    {"config", "Get and set variables in a configuration file."},
    {"daemon", "Run record sessions on background"},
    {"data", "Data file related processing"},
    {"diff", "Read perf.data files and display the differential profile"},
    {"evlist", "List the event names in a perf.data file"},
    {"ftrace", "simple wrapper for kernel's ftrace functionality"},
    {"inject", "Filter to augment the events stream with additional information"},
    {"iostat", "Show I/O performance metrics"},
    {"kallsyms", "Searches running kernel for symbols"},
    {"kvm", "Tool to trace/measure kvm guest os"},
    {"list", "List all symbolic event types"},
    {"mem", "Profile memory accesses"},
    {"record", "Run a command and record its profile into perf.data"},
    {"report", "Read perf.data (created by perf record) and display the profile"},
    {"script", "Read perf.data (created by perf record) and display trace output"},
    {"stat", "Run a command and gather performance counter statistics"},
    {"test", "Runs sanity tests."},
    {"top", "System profiling tool."},
    {"version", "display the version of perf binary"},
  #ifdef HAVE_LIBELF_SUPPORT
    {"probe", "Define new dynamic tracepoints"},
  #endif /* HAVE_LIBELF_SUPPORT */
  #if defined(HAVE_LIBTRACEEVENT) && (defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT))
    {"trace", "strace inspired tool"},
  #endif /* HAVE_LIBTRACEEVENT && (HAVE_LIBAUDIT_SUPPORT || HAVE_SYSCALL_TABLE_SUPPORT) */
  #ifdef HAVE_LIBTRACEEVENT
    {"kmem", "Tool to trace/measure kernel memory properties"},
    {"kwork", "Tool to trace/measure kernel work properties (latencies)"},
    {"lock", "Analyze lock events"},
    {"sched", "Tool to trace/measure scheduler properties (latencies)"},
    {"timechart", "Tool to visualize total system behavior during a workload"},
  #endif /* HAVE_LIBTRACEEVENT */
  };

Fixes: 378ef0f5d9d7f465 ("perf build: Use libtraceevent from the system")
Signed-off-by: Yang Jihong 
Acked-by: Namhyung Kim 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20221226085703.95081-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo