1. 11 Feb, 2021 10 commits
    • Jiri Olsa's avatar
      perf daemon: Set control fifo for session · 6a6d1804
      Jiri Olsa authored
      Setup control fifos for session and add --control option to session
      arguments.
      
      Example:
      
        # cat ~/.perfconfig
        [daemon]
        base=/opt/perfdata
      
        [session-cycles]
        run = -m 10M -e cycles --overwrite --switch-output -a
      
        [session-sched]
        run = -m 20M -e sched:* --overwrite --switch-output -a
      
      Starting the daemon:
      
        # perf daemon start
      
      Use can list control fifos with (control and ack files):
      
        # perf daemon -v
        [776459:daemon] base: /opt/perfdata
          output:  /opt/perfdata/output
          lock:    /opt/perfdata/lock
        [776460:cycles] perf record -m 20M -e cycles --overwrite --switch-output -a
          base:    /opt/perfdata/session-cycles
          output:  /opt/perfdata/session-cycles/output
          control: /opt/perfdata/session-cycles/control
          ack:     /opt/perfdata/session-cycles/ack
        [776461:sched] perf record -m 20M -e sched:* --overwrite --switch-output -a
          base:    /opt/perfdata/session-sched
          output:  /opt/perfdata/session-sched/output
          control: /opt/perfdata/session-sched/control
          ack:     /opt/perfdata/session-sched/ack
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-15-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      6a6d1804
    • Jiri Olsa's avatar
      perf daemon: Allow only one daemon over base directory · 8c98be6c
      Jiri Olsa authored
      Add 'lock' file under daemon base and flock it, so only one perf daemon
      can run on top of it.
      
      Each daemon tries to create and lock BASE/lock file, if it's successful
      we are sure we're the only daemon running over the BASE.
      
      Once daemon is finished, file descriptor to lock file is closed and lock
      is released.
      
      Example:
      
        # cat ~/.perfconfig
        [daemon]
        base=/opt/perfdata
      
        [session-cycles]
        run = -m 10M -e cycles --overwrite --switch-output -a
      
        [session-sched]
        run = -m 20M -e sched:* --overwrite --switch-output -a
      
      Starting the daemon:
      
        # perf daemon start
      
      And try once more:
      
        # perf daemon start
        failed: another perf daemon (pid 775594) owns /opt/perfdata
      
      will end up with an error, because there's already one running
      on top of /opt/perfdata.
      
      Committer notes:
      
      Provide lockf(F_TLOCK) when not available, i.e. transform:
      
        lockf(fd, F_TLOCK, 0);
      
      into:
      
        flock(fd, LOCK_EX | LOCK_NB);
      
      Which should be equivalent.
      
      Noticed when cross building to some odd Android NDK.
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-14-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      8c98be6c
    • Jiri Olsa's avatar
      perf daemon: Add 'stop' command · 23c5831e
      Jiri Olsa authored
      Add 'perf daemon stop' command to stop daemon process and all running
      sessions.
      
      Example:
      
        # cat ~/.perfconfig
        [daemon]
        base=/opt/perfdata
      
        [session-cycles]
        run = -m 10M -e cycles --overwrite --switch-output -a
      
        [session-sched]
        run = -m 20M -e sched:* --overwrite --switch-output -a
      
      Start the daemon:
      
        # perf daemon start
      
      Stop the daemon
      
        # perf daemon stop
      
      Daemon is not running, nothing to connect to:
      
        # perf daemon
        connect error: Connection refused
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-13-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      23c5831e
    • Jiri Olsa's avatar
      perf daemon: Add 'signal' command · 2d6914cd
      Jiri Olsa authored
      Allow the 'perf daemon' to send SIGUSR2 to all running sessions or just
      to a specific session.
      
      Example:
      
        # cat ~/.perfconfig
        [daemon]
        base=/opt/perfdata
      
        [session-cycles]
        run = -m 10M -e cycles --overwrite --switch-output -a
      
        [session-sched]
        run = -m 20M -e sched:* --overwrite --switch-output -a
      
      Start the daemon:
      
        # perf daemon start
      
      Send signal to all running sessions:
      
        # perf daemon signal
        signal 12 sent to session 'cycles [773738]'
        signal 12 sent to session 'sched [773739]'
      
      Or to specific one:
      
        # perf daemon signal --session sched
        signal 12 sent to session 'sched [773739]'
      
      And verify signals were delivered and perf.data dumped:
      
        # cat /opt/perfdata/session-cycles/output
        rounding mmap pages size to 32M (8192 pages)
        [ perf record: dump data: Woken up 1 times ]
        [ perf record: Dump perf.data.2021010220382490 ]
      
        # car /opt/perfdata/session-sched/output
        rounding mmap pages size to 32M (8192 pages)
        [ perf record: dump data: Woken up 1 times ]
        [ perf record: Dump perf.data.2021010220382489 ]
        [ perf record: dump data: Woken up 1 times ]
        [ perf record: Dump perf.data.2021010220393745 ]
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-12-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      2d6914cd
    • Jiri Olsa's avatar
      perf daemon: Add 'list' command · b325f7be
      Jiri Olsa authored
      Add a 'list' command to display all running sessions.  It's the default
      command if no other command is specified.
      
      Example:
      
        # cat ~/.perfconfig
        [daemon]
        base=/opt/perfdata
      
        [session-cycles]
        run = -m 10M -e cycles --overwrite --switch-output -a
      
        [session-sched]
        run = -m 20M -e sched:* --overwrite --switch-output -a
      
      Start the daemon:
      
        # perf daemon start
      
      List sessions:
      
        # perf daemon
        [771394:daemon] base: /opt/perfdata
        [771395:cycles] perf record -m 10M -e cycles --overwrite --switch-output -a
        [771396:sched] perf record -m 20M -e sched:* --overwrite --switch-output -a
      
      List sessions with more info:
      
        # perf daemon -v
        [771394:daemon] base: /opt/perfdata
          output:  /opt/perfdata/output
        [771395:cycles] perf record -m 10M -e cycles --overwrite --switch-output -a
          base:    /opt/perfdata/session-cycles
          output:  /opt/perfdata/session-cycles/output
        [771396:sched] perf record -m 20M -e sched:* --overwrite --switch-output -a
          base:    /opt/perfdata/session-sched
          output:  /opt/perfdata/session-sched/output
      
      The 'output' file is perf record output for specific session.
      
      Note you have to stop all running perf processes manually at this point,
      stop command is coming in following patches.
      
      Committer notes:
      
      Fixup union initialization to overcome this in multiple older systems:
      
        22    15.74 debian:8                      : FAIL gcc version 4.9.2 (Debian 4.9.2-10+deb8u2)
      
          builtin-daemon.c: In function 'send_cmd_list':
          builtin-daemon.c:1386:2: error: missing initializer for field 'csv_sep' of 'struct <anonymous>' [-Werror=missing-field-initializers]
            };
            ^
          builtin-daemon.c:641:8: note: 'csv_sep' declared here
             char csv_sep;
                  ^
          cc1: all warnings being treated as errors
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-11-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      b325f7be
    • Jiri Olsa's avatar
      perf daemon: Add signalfd support · 12c1a415
      Jiri Olsa authored
      Use a signalfd fd to track SIGCHLD signals as notifications for perf
      session termination.
      
      This way we don't need to actively check for child status, being
      notified if there's change.
      Suggested-by: default avatarAlexei Budankov <abudankov@huawei.com>
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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/20210208200908.1019149-10-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      12c1a415
    • Jiri Olsa's avatar
      perf daemon: Add background support · 88adb119
      Jiri Olsa authored
      Add support to put the daemon process in the background.
      
      It's now enabled by default and -f option is added to keep the daemon
      process on the console for debugging.
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-9-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      88adb119
    • Jiri Olsa's avatar
      perf daemon: Add config file change check · 3cda0625
      Jiri Olsa authored
      Add support to detect changes to the daemon's config file triggering a
      re-read of the configuration when that happens.
      
      Use a inotify file descriptor plugged into the main fdarray object for
      polling.
      
      Example:
      
        # cat ~/.perfconfig
        [daemon]
        base=/opt/perfdata
      
        [session-cycles]
        run = -m 10M -e cycles --overwrite --switch-output -a
      
      Starting the daemon:
      
        # perf daemon start
      
      Check sessions:
      
        # perf daemon
        [772262:daemon] base: /opt/perfdata
        [772263:cycles] perf record -m 10M -e cycles --overwrite --switch-output -a
      
      Change '-m 10M' to '-m 20M', and check daemon log:
      
        # tail -f /opt/perfdata/output
        [2021-01-02 20:31:41.234045] daemon started (pid 772262)
        [2021-01-02 20:31:41.235072] reconfig: ruining session [cycles:772263]: -m 10M -e cycles --overwrite --switch-output -a
        [2021-01-02 20:32:08.310137] reconfig: session 'cycles' killed
        [2021-01-02 20:32:08.310847] reconfig: ruining session [cycles:772338]: -m 20M -e cycles --overwrite --switch-output -a
      
      And the session list:
      
        # perf daemon
        [772262:daemon] base: /opt/perfdata
        [772338:cycles] perf record -m 20M -e cycles --overwrite --switch-output -a
      
      Note the changed '-m 20M' option is in place.
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-8-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      3cda0625
    • Jiri Olsa's avatar
      perf daemon: Add config file support · c0666261
      Jiri Olsa authored
      Adding support to configure daemon with config file.
      
      Each client or server invocation of perf daemon needs to know the
      base directory, where all sessions data is stored.
      
      The base is defined with:
      
        daemon.base
          Base path for daemon data. All sessions data are stored under
          this path.
      
      The daemon allows to create record sessions. Each session is a
      record command spawned and monitored by perf daemon.
      
      The session is defined with:
      
        session-<NAME>.run
          Defines new record session for daemon. The value is record's
          command line without the 'record' keyword.
      
      Example:
      
        # cat ~/.perfconfig
        [daemon]
        base=/opt/perfdata
      
        [session-cycles]
        run = -m 10M -e cycles --overwrite --switch-output -a
      
        [session-sched]
        run = -m 20M -e sched:* --overwrite --switch-output -a
      
      The example above defines '/opt/perfdata' as the base directory and 2
      record sessions.
      
        # perf daemon start
        [2021-01-28 19:47:33.454413] daemon started (pid 16015)
        [2021-01-28 19:47:33.455910] reconfig: ruining session [cycles:16016]: -m 10M -e cycles --overwrite --switch-output -a
        [2021-01-28 19:47:33.456599] reconfig: ruining session [sched:16017]: -m 20M -e sched:* --overwrite --switch-output -a
      
        # ps -ef | grep perf
        ... perf daemon start
        ... /home/jolsa/.../perf record -m 20M -e cycles --overwrite --switch-output -a
        ... /home/jolsa/.../perf record -m 20M -e sched:* --overwrite --switch-output -a
      
      The base directory is populated with:
      
        # find /opt/perfdata/
        /opt/perfdata/
        /opt/perfdata/control                    <- control socket
        /opt/perfdata/session-cycles             <- data for session 'cycles':
        /opt/perfdata/session-cycles/output      <-   perf record output
        /opt/perfdata/session-cycles/perf.data   <-   perf data
        /opt/perfdata/session-sched              <- ditto for session 'sched'
        /opt/perfdata/session-sched/output
        /opt/perfdata/session-sched/perf.data
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-7-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      c0666261
    • Jiri Olsa's avatar
      perf daemon: Add client socket support · 90b0aad8
      Jiri Olsa authored
      Add support for client socket side that will be used to send commands to
      the daemon server socket.
      
      This patch adds only the core support, all commands using this
      functionality are coming in the following patches.
      
      Committer notes:
      
      Hat to patch patch it to deal with this in some systems:
      
        cc1: warnings being treated as errors
        builtin-daemon.c: In function 'send_cmd':  MKDIR    /tmp/build/perf/bench/
      
        builtin-daemon.c:1368: error: ignoring return value of 'fwrite', declared with attribute warn_unused_result
          MKDIR    /tmp/build/perf/tests/
        make[3]: *** [/tmp/build/perf/builtin-daemon.o] Error 1
      
      And also to not leak the 'line' buffer allocated by getline(), since you
      initialized line to NULL and len to zero, man page says:
      
        If *lineptr is set to NULL and *n is set 0 before the call,
        then getline() will allocate a buffer for storing the line.
        This buffer should be freed by the user program even if
        getline() failed.
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-6-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      90b0aad8
  2. 09 Feb, 2021 7 commits
    • Jiri Olsa's avatar
      perf daemon: Add server socket support · ed36b704
      Jiri Olsa authored
      Add support to create a server socket that listens for client commands
      and processes them.
      
      This patch adds only the core support, all commands using this
      functionality are coming in the following patches.
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-5-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      ed36b704
    • Jiri Olsa's avatar
      perf daemon: Add base option · 5631d100
      Jiri Olsa authored
      Add a base option allowing the user to specify a base directory.  It
      will have precedence over config file base definition coming in the
      following patches.
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-4-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      5631d100
    • Jiri Olsa's avatar
      perf daemon: Add config option · fc1dcb1e
      Jiri Olsa authored
      Add a config option and base functionality that takes the option
      argument (if specified) and other system config locations and produces
      an 'acting' config file path.
      
      The actual config file processing is coming in following patches.
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      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/20210208200908.1019149-3-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      fc1dcb1e
    • Jiri Olsa's avatar
      perf daemon: Add daemon command · d450bc50
      Jiri Olsa authored
      Add a daemon skeleton with a minimal base (non) functionality, covering
      various setup in start command.
      
      Add an initial perf-daemon.txt with basic info.
      
      This is in response to pople asking for the possibility to be able run
      record long running sessions on the background.
      
      The patchset that starts with this adds support to configure and run
      record sessions on background via new 'perf daemon' command.
      
      This is useful for being able to use perf as a flight recorder that one
      can interact with asking for events to be enabled or disabled, added or
      removed, etc.
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Alexei Budankov <abudankov@huawei.com>
      Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
      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/20210208200908.1019149-2-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      d450bc50
    • Yang Li's avatar
      perf script: Simplify bool conversion · 8524711d
      Yang Li authored
        Fix the following coccicheck warning:
        ./tools/perf/builtin-script.c:2789:36-41: WARNING: conversion to bool
        not needed here
        ./tools/perf/builtin-script.c:3237:48-53: WARNING: conversion to bool
        not needed here
      Reported-by: default avatarAbaci Robot <abaci@linux.alibaba.com>
      Signed-off-by: default avatarYang Li <yang.lee@linux.alibaba.com>
      Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Alexei Starovoitov <ast@kernel.org>
      Cc: Andrii Nakryiko <andrii@kernel.org>
      Cc: Daniel Borkmann <daniel@iogearbox.net>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: John Fastabend <john.fastabend@gmail.com>
      Cc: KP Singh <kpsingh@kernel.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Martin KaFai Lau <kafai@fb.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Song Liu <songliubraving@fb.com>
      Cc: Yonghong Song <yhs@fb.com>
      Link: https://lore.kernel.org/r/1612773936-98691-1-git-send-email-yang.lee@linux.alibaba.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      8524711d
    • Arnaldo Carvalho de Melo's avatar
      perf arm64/s390: Fix printf conversion specifier for IP addresses · 6db59d35
      Arnaldo Carvalho de Melo authored
      We need to use "%#" PRIx64 for u64 values, not "%lx". In arm64's and
      s390x cases the compiler doesn't complain, but lets fix this in case
      this code gets copied to a 32-bit arch, like with powerpc 32-bit that
      got fixed in the previous patch.
      
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Hewenliang <hewenliang4@huawei.com>
      Cc: Hu Shiyuan <hushiyuan@huawei.com>
      Cc: Ian Rogers <irogers@google.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Nick Desaulniers <ndesaulniers@google.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Richter <tmricht@linux.ibm.com>
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      6db59d35
    • Arnaldo Carvalho de Melo's avatar
      perf powerpc: Fix printf conversion specifier for IP addresses · 0f000f9c
      Arnaldo Carvalho de Melo authored
      We need to use "%#" PRIx64 for u64 values, not "%lx", fixing this build
      problem on powerpc 32-bit:
      
        72    13.69 ubuntu:18.04-x-powerpc        : FAIL powerpc-linux-gnu-gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
          arch/powerpc/util/machine.c: In function 'arch__symbols__fixup_end':
          arch/powerpc/util/machine.c:23:12: error: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type 'u64 {aka long long unsigned int}' [-Werror=format=]
            pr_debug4("%s sym:%s end:%#lx\n", __func__, p->name, p->end);
                      ^
          /git/linux/tools/perf/util/debug.h:18:21: note: in definition of macro 'pr_fmt'
           #define pr_fmt(fmt) fmt
                               ^~~
          /git/linux/tools/perf/util/debug.h:33:29: note: in expansion of macro 'pr_debugN'
           #define pr_debug4(fmt, ...) pr_debugN(4, pr_fmt(fmt), ##__VA_ARGS__)
                                       ^~~~~~~~~
          /git/linux/tools/perf/util/debug.h:33:42: note: in expansion of macro 'pr_fmt'
           #define pr_debug4(fmt, ...) pr_debugN(4, pr_fmt(fmt), ##__VA_ARGS__)
                                                    ^~~~~~
          arch/powerpc/util/machine.c:23:2: note: in expansion of macro 'pr_debug4'
            pr_debug4("%s sym:%s end:%#lx\n", __func__, p->name, p->end);
            ^~~~~~~~~
          cc1: all warnings being treated as errors
          /git/linux/tools/build/Makefile.build:139: recipe for target 'util' failed
          make[5]: *** [util] Error 2
          /git/linux/tools/build/Makefile.build:139: recipe for target 'powerpc' failed
          make[4]: *** [powerpc] Error 2
          /git/linux/tools/build/Makefile.build:139: recipe for target 'arch' failed
          make[3]: *** [arch] Error 2
        73    30.47 ubuntu:18.04-x-powerpc64      : Ok   powerpc64-linux-gnu-gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
      
      Fixes: 557c3ead ("perf powerpc: Fix gap between kernel end and module start")
      Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Kajol Jain <kjain@linux.ibm.com>
      Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      0f000f9c
  3. 08 Feb, 2021 14 commits
    • Jin Yao's avatar
      perf script: Support filtering by hex address · 61d9fc44
      Jin Yao authored
      'perf script' supports '-S' or '--symbol' options to only list the
      records for these symbols. A symbol is typically a name or hex address.
      If it's hex address, it is the start address of one symbol.
      
      While it would be useful if we can filter trace records by any hex
      address (not only the start address of symbol). So now we support
      filtering trace records by more conditions, such as:
      
      - symbol name
      - start address of symbol
      - any hexadecimal address
      - address range
      
      The comparison order is defined as:
      
      1. symbol name comparison
      2. symbol start address comparison.
      3. any hexadecimal address comparison.
      4. address range comparison.
      
      The idea is if we can get a valid address from -S list, we add the
      address to addr_list for address comparison otherwise we still leave
      it to sym_list for symbol comparison.
      
      Some examples:
      
        root@kbl-ppc:~# ./perf script -S ffffffff9a477308
                  perf  8562 [000] 347303.578858:          1   cycles:  ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms])
                  perf  8562 [000] 347303.578860:          1   cycles:  ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms])
                  perf  8562 [000] 347303.578861:         11   cycles:  ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms])
                  perf  8562 [001] 347303.578903:          1   cycles:  ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms])
                  perf  8562 [001] 347303.578905:          1   cycles:  ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms])
                  perf  8562 [001] 347303.578906:         15   cycles:  ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms])
                  perf  8562 [002] 347303.578952:          1   cycles:  ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms])
                  perf  8562 [002] 347303.578953:          1   cycles:  ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms])
      
      Filter the traced records by hex address ffffffff9a477308.
      
        root@kbl-ppc:~# ./perf script -S ffffffff9a4dd4ce,ffffffff9a4d2de9,ffffffff9a6bf9f4
                  perf  8562 [001] 347303.578911:     311706   cycles:  ffffffff9a6bf9f4 __kmalloc_node+0x204 ([kernel.kallsyms])
                  perf  8562 [002] 347303.578960:     354477   cycles:  ffffffff9a4d2de9 sched_setaffinity+0x49 ([kernel.kallsyms])
                  perf  8562 [003] 347303.579015:     450958   cycles:  ffffffff9a4dd4ce dequeue_task_fair+0x1ae ([kernel.kallsyms])
      
      Filter the traced records by hex address ffffffff9a4dd4ce, ffffffff9a4d2de9, ffffffff9a6bf9f4.
      
        root@kbl-ppc:~# ./perf script -S ffffffff9a477309 --addr-range 16
                  perf  8562 [000] 347303.578863:        291   cycles:  ffffffff9a47730a native_write_msr+0xa ([kernel.kallsyms])
                  perf  8562 [001] 347303.578907:        411   cycles:  ffffffff9a47730a native_write_msr+0xa ([kernel.kallsyms])
                  perf  8562 [002] 347303.578956:        462   cycles:  ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms])
                  perf  8562 [003] 347303.579010:        497   cycles:  ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms])
                  perf  8562 [004] 347303.579059:        429   cycles:  ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms])
                  perf  8562 [005] 347303.579109:        408   cycles:  ffffffff9a47730a native_write_msr+0xa ([kernel.kallsyms])
                  perf  8562 [006] 347303.579159:        460   cycles:  ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms])
                  perf  8562 [007] 347303.579213:        436   cycles:  ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms])
      
      Filter the traced records from address range [ffffffff9a477309, ffffffff9a477309 + 15].
      
        root@kbl-ppc:~# ./perf script -S "ffffffff9b163046,rcu_nmi_exit"
                  perf  8562 [004] 347303.579060:      12013   cycles:  ffffffff9b163046 exc_nmi+0x166 ([kernel.kallsyms])
                  perf  8562 [007] 347303.579214:      12138   cycles:  ffffffff9b165944 rcu_nmi_exit+0x34 ([kernel.kallsyms])
      
      Filter by address + symbol
      Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
      Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@intel.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Kan Liang <kan.liang@linux.intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Link: http://lore.kernel.org/lkml/20210207080935.31784-2-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      61d9fc44
    • Jin Yao's avatar
      perf intlist: Change 'struct intlist' int member to 'unsigned long' · 94253393
      Jin Yao authored
      This is to let intlist support addresses as its payload.
      
      One potential problem is it can't support negative number. But so far,
      there is no such kind of use case.
      Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@intel.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Kan Liang <kan.liang@linux.intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Link: http://lore.kernel.org/lkml/20210207080935.31784-1-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      94253393
    • Paul Cercueil's avatar
      perf stat: Use nftw() instead of ftw() · a81fbb87
      Paul Cercueil authored
      ftw() has been obsolete for about 12 years now.
      
      Committer notes:
      
      Further notes provided by the patch author:
      
          "NOTE: Not runtime-tested, I have no idea what I need to do in perf
           to test this. But at least it compiles now with my uClibc-based
           toolchain."
      
      I looked at the nftw()/ftw() man page and for the use made with cgroups
      in 'perf stat' the end result is equivalent.
      
      Fixes: bb1c15b6 ("perf stat: Support regex pattern in --for-each-cgroup")
      Signed-off-by: default avatarPaul Cercueil <paul@crapouillou.net>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: od@zcrc.me
      Cc: stable@vger.kernel.org
      Link: http://lore.kernel.org/lkml/20210208181157.1324550-1-paul@crapouillou.netSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      a81fbb87
    • Kan Liang's avatar
      perf tools: Update topdown documentation for Sapphire Rapids · 7d91e818
      Kan Liang authored
      Update Topdown extension on Sapphire Rapids and how to collect the L2
      events.
      Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/1612296553-21962-10-git-send-email-kan.liang@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      7d91e818
    • Kan Liang's avatar
      perf stat: Support L2 Topdown events · 63e39aa6
      Kan Liang authored
      The TMA method level 2 metrics is supported from the Intel Sapphire
      Rapids server, which expose four L2 Topdown metrics events to user
      space. There are eight L2 events in total. The other four L2 Topdown
      metrics events are calculated from the corresponding L1 and the exposed
      L2 events.
      
      Now, the --topdown prints the complete top-down metrics that supported
      by the CPU. For the Intel Sapphire Rapids server, there are 4 L1 events
      and 8 L2 events displyed in one line.
      
      Add a new option, --td-level, to display the top-down statistics that
      equal to or lower than the input level.
      
      The L2 event is marked only when both its L1 parent event and itself
      crosse the threshold.
      
      Here is an example:
      
        $ perf stat --topdown --td-level=2 --no-metric-only sleep 1
        Topdown accuracy may decrease when measuring long periods.
        Please print the result regularly, e.g. -I1000
      
        Performance counter stats for 'sleep 1':
      
           16,734,390   slots
            2,100,001   topdown-retiring       # 12.6% retiring
            2,034,376   topdown-bad-spec       # 12.3% bad speculation
            4,003,128   topdown-fe-bound       # 24.1% frontend bound
              328,125   topdown-heavy-ops      #  2.0% heavy operations    #  10.6% light operations
            1,968,751   topdown-br-mispredict  # 11.9% branch mispredict   #  0.4% machine clears
            2,953,127   topdown-fetch-lat      # 17.8% fetch latency       #  6.3% fetch bandwidth
            5,906,255   topdown-mem-bound      # 35.6% memory bound        #  15.4% core bound
      Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/1612296553-21962-9-git-send-email-kan.liang@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      63e39aa6
    • Kan Liang's avatar
      perf test: Support PERF_SAMPLE_WEIGHT_STRUCT · c7444297
      Kan Liang authored
      Support the new sample type for sample-parsing test case.
      Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/1612296553-21962-8-git-send-email-kan.liang@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      c7444297
    • Kan Liang's avatar
      perf report: Support instruction latency · 590db42d
      Kan Liang authored
      The instruction latency information can be recorded on some platforms,
      e.g., the Intel Sapphire Rapids server. With both memory latency
      (weight) and the new instruction latency information, users can easily
      locate the expensive load instructions, and also understand the time
      spent in different stages. The users can optimize their applications in
      different pipeline stages.
      
      The 'weight' field is shared among different architectures. Reusing the
      'weight' field may impacts other architectures. Add a new field to store
      the instruction latency.
      
      Like the 'weight' support, introduce a 'ins_lat' for the global
      instruction latency, and a 'local_ins_lat' for the local instruction
      latency version.
      
      Add new sort functions, INSTR Latency and Local INSTR Latency,
      accordingly.
      
      Add local_ins_lat to the default_mem_sort_order[].
      Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/1612296553-21962-7-git-send-email-kan.liang@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      590db42d
    • Kan Liang's avatar
      perf tools: Support PERF_SAMPLE_WEIGHT_STRUCT · ea8d0ed6
      Kan Liang authored
      The new sample type, PERF_SAMPLE_WEIGHT_STRUCT, is an alternative of the
      PERF_SAMPLE_WEIGHT sample type. Users can apply either the
      PERF_SAMPLE_WEIGHT sample type or the PERF_SAMPLE_WEIGHT_STRUCT sample
      type to retrieve the sample weight, but they cannot apply both sample
      types simultaneously.
      
      The new sample type shares the same space as the PERF_SAMPLE_WEIGHT
      sample type. The lower 32 bits are exactly the same for both sample
      type. The higher 32 bits may be different for different architecture.
      
      Add arch specific arch_evsel__set_sample_weight() to set the new sample
      type for X86. Only store the lower 32 bits for the sample->weight if the
      new sample type is applied. In practice, no memory access could last
      than 4G cycles. No data will be lost.
      
      If the kernel doesn't support the new sample type. Fall back to the
      PERF_SAMPLE_WEIGHT sample type.
      
      There is no impact for other architectures.
      
      Committer notes:
      
      Fixup related to PERF_SAMPLE_CODE_PAGE_SIZE, present in acme/perf/core
      but not upstream yet.
      Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/1612296553-21962-6-git-send-email-kan.liang@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      ea8d0ed6
    • Kan Liang's avatar
      perf c2c: Support data block and addr block · d9d5d767
      Kan Liang authored
      'perf c2c' is also a memory profiling tool. Apply the two new data
      source fields to 'perf c2c' as well.
      
      Extend 'perf c2c' to display the number of loads which blocked by data or
      address conflict.
      Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Don Zickus <dzickus@redhat.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Joe Mario <jmario@redhat.com>
      Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/1612296553-21962-5-git-send-email-kan.liang@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      d9d5d767
    • Kan Liang's avatar
      perf tools: Support data block and addr block · a054c298
      Kan Liang authored
      Two new data source fields, to indicate the block reasons of a load
      instruction, are introduced on the Intel Sapphire Rapids server. The
      fields can be used by the memory profiling.
      
      Add a new sort function, SORT_MEM_BLOCKED, for the two fields.
      
      For the previous platforms or the block reason is unknown, print "N/A"
      for the block reason.
      
      Add blocked as a default mem sort key for perf report and perf mem
      report.
      
      Committer testing:
      
      So in machines without this capability we get a "N/A" filling the new "Blocked"
      column:
      
        $ perf mem record ls
        arch     certs	 CREDITS  Documentation  include  ipc     Kconfig  lib       MAINTAINERS  mm   samples  security  usr    block
        COPYING	 crypto	 drivers  fs             init     Kbuild  kernel   LICENSES  Makefile     net  README   scripts   sound  tools
        virt
        [ perf record: Woken up 1 times to write data ]
        [ perf record: Captured and wrote 0.008 MB perf.data (17 samples) ]
        $
        $ perf mem report --stdio
        # To display the perf.data header info, please use --header/--header-only options.
        #
        # Total Lost Samples: 0
        #
        # Samples: 6  of event 'cpu/mem-loads,ldlat=30/Pu'
        # Total weight : 1381
        # Sort order   : local_weight,mem,sym,dso,symbol_daddr,dso_daddr,snoop,tlb,locked,blocked
        #
        # Overhead  Samples  Local Weight  Memory access         Symbol                   Shared Object  Data Symbol             Data Object   Snoop  TLB access    Locked  Blocked
        # ........  .......  ............  ....................  .......................  .............  ......................  ............  .....  ............  ......  .......
        #
            32.87%        1  454           Local RAM or RAM hit  [.] _dl_relocate_object  ld-2.31.so     [.] 0x00007fe91cef3078  libc-2.31.so  Hit    L1 or L2 hit  No       N/A
            25.56%        1  353           LFB or LFB hit        [.] strcmp               ld-2.31.so     [.] 0x00005586973855ca  ls            None   L1 or L2 hit  No       N/A
            22.59%        1  312           LFB or LFB hit        [.] _dl_cache_libcmp     ld-2.31.so     [.] 0x00007fe91d0e3b18  ld.so.cache   None   L1 or L2 hit  No       N/A
             8.47%        1  117           LFB or LFB hit        [.] _dl_relocate_object  ld-2.31.so     [.] 0x00007fe91ceee570  libc-2.31.so  None   L1 or L2 hit  No       N/A
             6.88%        1  95            LFB or LFB hit        [.] _dl_relocate_object  ld-2.31.so     [.] 0x00007fe91ceed490  libc-2.31.so  None   L1 or L2 hit  No       N/A
             3.62%        1  50            LFB or LFB hit        [.] _dl_cache_libcmp     ld-2.31.so     [.] 0x00007fe91d0ebe60  ld.so.cache   None   L1 or L2 hit  No       N/A
      
        # Samples: 11  of event 'cpu/mem-stores/Pu'
        # Total weight : 11
        # Sort order   : local_weight,mem,sym,dso,symbol_daddr,dso_daddr,snoop,tlb,locked,blocked
        #
        # Overhead  Samples  Local Weight  Memory access  Symbol                   Shared Object  Data Symbol             Data Object  Snoop  TLB access  Locked  Blocked
        # ........  .......  ............  .............  .......................  .............  ......................  ...........  .....  ..........  ......  .......
        #
             9.09%        1  0             L1 hit         [.] __strcoll_l          libc-2.31.so   [.] 0x00007fffe5648fc8  [stack]      N/A    N/A         N/A      N/A
             9.09%        1  0             L1 hit         [.] _dl_lookup_symbol_x  ld-2.31.so     [.] 0x00007fffe56490b8  [stack]      N/A    N/A         N/A      N/A
             9.09%        1  0             L1 hit         [.] _dl_name_match_p     ld-2.31.so     [.] 0x00007fffe56487d8  [stack]      N/A    N/A         N/A      N/A
             9.09%        1  0             L1 hit         [.] _dl_start            ld-2.31.so     [.] start_time+0x0      ld-2.31.so   N/A    N/A         N/A      N/A
             9.09%        1  0             L1 hit         [.] _dl_sysdep_start     ld-2.31.so     [.] 0x00007fffe56494b8  [stack]      N/A    N/A         N/A      N/A
             9.09%        1  0             L1 hit         [.] do_lookup_x          ld-2.31.so     [.] 0x00007fffe5648ff8  [stack]      N/A    N/A         N/A      N/A
             9.09%        1  0             L1 hit         [.] do_lookup_x          ld-2.31.so     [.] 0x00007fffe5649064  [stack]      N/A    N/A         N/A      N/A
             9.09%        1  0             L1 hit         [.] do_lookup_x          ld-2.31.so     [.] 0x00007fffe5649130  [stack]      N/A    N/A         N/A      N/A
             9.09%        1  0             L1 miss        [.] _dl_start            ld-2.31.so     [.] _rtld_global+0xaf8  ld-2.31.so   N/A    N/A         N/A      N/A
             9.09%        1  0             L1 miss        [.] _dl_start            ld-2.31.so     [.] _rtld_global+0xc28  ld-2.31.so   N/A    N/A         N/A      N/A
             9.09%        1  0             L1 miss        [.] _dl_start            ld-2.31.so     [.] 0x00007fffe56495b8  [stack]      N/A    N/A         N/A      N/A
      
        # (Tip: Show user configuration overrides: perf config --user --list)
        $
      Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/1612296553-21962-4-git-send-email-kan.liang@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      a054c298
    • Kan Liang's avatar
      perf tools: Support the auxiliary event · 2a57d408
      Kan Liang authored
      On the Intel Sapphire Rapids server, an auxiliary event has to be
      enabled simultaneously with the load latency event to retrieve complete
      Memory Info.
      
      Add X86 specific perf_mem_events__name() to handle the auxiliary event.
      
      - Users are only interested in the samples of the mem-loads event.
        Sample read the auxiliary event.
      
      - The auxiliary event must be in front of the load latency event in a
        group. Assume the second event to sample if the auxiliary event is the
        leader.
      
      - Add a weak is_mem_loads_aux_event() to check the auxiliary event for
        X86. For other ARCHs, it always return false.
      
      Parse the unique event name, mem-loads-aux, for the auxiliary event.
      
      Committer notes:
      
      According to 61b985e3 ("perf/x86/intel: Add perf core PMU
      support for Sapphire Rapids"), ENODATA is only returned by
      sys_perf_event_open() when used with these auxiliary events, with this
      in evsel__open_strerror():
      
             case ENODATA:
                     return scnprintf(msg, size, "Cannot collect data source with the load latency event alone. "
                                      "Please add an auxiliary event in front of the load latency event.");
      
      This is Ok at this point in time, but fragile long term, I pointed this
      out in the e-mail thread, requesting a follow up patch to check if
      ENODATA is really for this specific case.
      
      Fixed up sizeof(MEM_LOADS_AUX_NAME) bug pointed out by Namhyung.
      Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/20210205152648.GC920417@kernel.org
      Link: http://lore.kernel.org/lkml/1612296553-21962-3-git-send-email-kan.liang@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      2a57d408
    • Kan Liang's avatar
      tools headers uapi: Update tools's copy of linux/perf_event.h · 81898ef1
      Kan Liang authored
      To get the changes in these csets:
      
        2a6c6b7d ("perf/core: Add PERF_SAMPLE_WEIGHT_STRUCT")
        61b985e3 ("perf/x86/intel: Add perf core PMU support for Sapphire Rapids")
      
      This cures the following warning during perf's build:
      
              Warning: Kernel ABI header at 'tools/include/uapi/linux/perf_event.h' differs from latest version at 'include/uapi/linux/perf_event.h'
              diff -u tools/include/uapi/linux/perf_event.h include/uapi/linux/perf_event.h
      
      Committer notes:
      
      Picked by hand as I had already merged the MMAP buildid patch that also touches
      perf_event.h and is also only in {acme,tip}/perf/core, not yet upstream.
      Signed-off-by: default avatarKan Liang <kan.liang@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/1612296553-21962-2-git-send-email-kan.liang@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      81898ef1
    • Athira Rajeev's avatar
      perf powerpc: Support exposing Performance Monitor Counter SPRs as part of extended regs · 068aeea3
      Athira Rajeev authored
      To enable presenting of Performance Monitor Counter Registers (PMC1 to
      PMC6) as part of extended regsiters, this patch adds these to
      sample_reg_mask in the tool side (to use with -I? option).
      
      Simplified the PERF_REG_PMU_MASK_300/31 definition. Excluded the
      unsupported SPRs (MMCR3, SIER2, SIER3) from extended mask value for
      CPU_FTR_ARCH_300.
      Signed-off-by: default avatarAthira Jajeev <atrajeev@linux.vnet.ibm.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Kajol Jain <kjain@linux.ibm.com>
      Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: linuxppc-dev@lists.ozlabs.org
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      068aeea3
    • Jianlin Lv's avatar
      perf probe: Add protection to avoid endless loop · 900547dd
      Jianlin Lv authored
      if dwarf_offdie() returns NULL, the continue statement forces the next
      iteration of the loop without updating the 'off' variable. It will cause
      an endless loop in the process of traversing the compile unit.  So add
      exception protection for looping CUs.
      Signed-off-by: default avatarJianlin Lv <Jianlin.Lv@arm.com>
      Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: jianlin.lv@arm.com
      Link: http://lore.kernel.org/lkml/20210203145702.1219509-1-Jianlin.Lv@arm.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      900547dd
  4. 03 Feb, 2021 9 commits
    • Ian Rogers's avatar
      perf trace-event-info: Rename for_each_event. · d2e31d7e
      Ian Rogers authored
      Avoid a naming conflict with for_each_event with similar code in
      parse-events.c, rename to for_each_event_tps.
      Signed-off-by: default avatarIan Rogers <irogers@google.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lore.kernel.org/lkml/20210203052659.2975736-1-irogers@google.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      d2e31d7e
    • Arnaldo Carvalho de Melo's avatar
    • Athira Rajeev's avatar
      perf powerpc: Fix gap between kernel end and module start · 557c3ead
      Athira Rajeev authored
      Running "perf mem report" in TUI mode fails with ENOMEM message in
      powerpc:
      
        failed to process sample
      
      Running with debug and verbose options points that issue is while
      allocating memory for sample histograms.
      
      The error path is:
      
        symbol__inc_addr_samples() ->
          __symbol__inc_addr_samples() ->
            annotated_source__histogram()
      
      symbol__inc_addr_samples() calls annotated_source__alloc_histograms ()
      to allocate memory for sample histograms using calloc(). Here calloc()
      fails since the size of symbol is huge. The size of a symbol is
      calculated as difference between its start and end address.
      
      Example histogram allocation that fails is:
      
        sym->name is _end
        sym->start is 0xc0000000027a0000
        sym->end is 0xc008000003890000
        symbol__size(sym) is 0x80000010f0000
      
      In the above case, the difference between sym->start
      (0xc0000000027a0000) and sym->end (0xc008000003890000) is huge.
      
      This is same problem as in s390 and arm64 which are fixed in commits:
      
        b9c0a649 ("perf annotate: Fix s390 gap between kernel end and module start")
        78886f3e ("perf symbols: Fix arm64 gap between kernel start and module end")
      
      When this symbol was read first, its start and end address was set to
      address which matches with data from /proc/kallsyms.
      
      After symbol__new():
      
        symbol__new: _end 0xc0000000027a0000-0xc0000000027a0000
      
        From /proc/kallsyms:
        ...
        c000000002799370 b backtrace_flag
        c000000002799378 B radix_tree_node_cachep
        c000000002799380 B __bss_stop
        c0000000027a0000 B _end
        c008000003890000 t icmp_checkentry      [ip_tables]
        c008000003890038 t ipt_alloc_initial_table      [ip_tables]
        c008000003890468 T ipt_do_table [ip_tables]
        c008000003890de8 T ipt_unregister_table_pre_exit        [ip_tables]
        ...
      
      Perf calls function symbols__fixup_end() which sets the end of symbol to
      0xc008000003890000, which is the next address and this is the start
      address of first module (icmp_checkentry in above) which will make the
      huge symbol size of 0x80000010f0000.
      
      After symbols__fixup_end:
      
        symbols__fixup_end: sym->name: _end
        sym->start: 0xc0000000027a0000
        sym->end: 0xc008000003890000
      
      On powerpc, kernel text segment is located at 0xc000000000000000 whereas
      the modules are located at very high memory addresses,
      0xc00800000xxxxxxx. Since the gap between end of kernel text segment and
      beginning of first module's address is high, histogram allocation using
      calloc fails.
      
      Fix this by detecting the kernel's last symbol and limiting the range of
      last kernel symbol to pagesize.
      
      Signed-off-by: Athira Rajeev<atrajeev@linux.vnet.ibm.com>
      Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
      Tested-By: default avatarKajol Jain <kjain@linux.ibm.com>
      Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Link: https://lore.kernel.org/r/1609208054-1566-1-git-send-email-atrajeev@linux.vnet.ibm.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      557c3ead
    • Yonatan Goldschmidt's avatar
      perf inject jit: Add namespaces support · 67dec926
      Yonatan Goldschmidt authored
      This patch fixes "perf inject --jit" to properly operate on
      namespaced/containerized processes:
      
      * jitdump files are generated by the process, thus they should be
        looked up in its mount NS.
      
      * DSOs of injected MMAP events will later be looked up in the process
        mount NS, so write them into its NS.
      
      * PIDs & TIDs from jitdump events need to be translated to the PID as
        seen by "perf record" before written into MMAP events.
      
      For a process in a different PID NS, the TID & PID given in the jitdump
      event are actually ignored; I use the TID & PID of the thread which
      mmap()ed the jitdump file. This is simplified and won't do for forks of
      the initial process, if they continue using the same jitdump file.
      Future patches might improve it.
      
      This was tested by recording a NodeJS process running with
      "--perf-prof", inside a Docker container, and by recording another
      NodeJS process running in the same namespaces as perf itself, to make
      sure it's not broken for non-containerized processes.
      Signed-off-by: default avatarYonatan Goldschmidt <yonatan.goldschmidt@granulate.io>
      Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
      Acked-by: default avatarNamhyung Kim <namhyung@kernel.org>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: https://lore.kernel.org/r/20201105015604.1726943-1-yonatan.goldschmidt@granulate.ioSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      67dec926
    • Yonatan Goldschmidt's avatar
      perf namespaces: Add 'in_pidns' to nsinfo struct · 2b51c71b
      Yonatan Goldschmidt authored
      Provides an accurate mean to determine if the owner thread is in a
      different PID namespace.
      Signed-off-by: default avatarYonatan Goldschmidt <yonatan.goldschmidt@granulate.io>
      Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
      Acked-by: default avatarNamhyung Kim <namhyung@kernel.org>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: https://lore.kernel.org/r/20201105015418.1725218-1-yonatan.goldschmidt@granulate.ioSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      2b51c71b
    • Namhyung Kim's avatar
      perf tools: Use scandir() to iterate threads when synthesizing PERF_RECORD_ events · 473f742e
      Namhyung Kim authored
      Like in __event__synthesize_thread(), I think it's better to use
      scandir() instead of the readdir() loop.  In case some malicious task
      continues to create new threads, the readdir() loop will run over and
      over to collect tids.  The scandir() also has the problem but the window
      is much smaller since it doesn't do much work during the iteration.
      
      Also add filter_task() function as we only care the tasks.
      Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
      Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Ian Rogers <irogers@google.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: https://lore.kernel.org/r/20210202090118.2008551-4-namhyung@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      473f742e
    • Namhyung Kim's avatar
      perf tools: Skip PERF_RECORD_MMAP event synthesis for kernel threads · c1b90795
      Namhyung Kim authored
      To synthesize information to resolve sample IPs, it needs to scan task
      and mmap info from the /proc filesystem.  For each process, it opens
      (and reads) status and maps file respectively.  But as kernel threads
      don't have memory maps so we can skip the maps file.
      
      To find kernel threads, check "VmPeak:" line in /proc/<PID>/status file.
      It's about the peak virtual memory usage so only user-level tasks have
      that.  Note that it's possible to miss the line due to partial reads.
      So we should double-check if it's a really kernel thread when there's no
      VmPeak line.
      
      Thus check "Threads:" line (which follows the VmPeak line whether or not
      it exists) to be sure it's read enough data - just in case of deeply
      nested pid namespaces or large number of supplementary groups are
      involved.
      
      This is for user process:
      
        $ head -40 /proc/1/status
        Name:	systemd
        Umask:	0000
        State:	S (sleeping)
        Tgid:	1
        Ngid:	0
        Pid:	1
        PPid:	0
        TracerPid:	0
        Uid:	0	0	0	0
        Gid:	0	0	0	0
        FDSize:	256
        Groups:
        NStgid:	1
        NSpid:	1
        NSpgid:	1
        NSsid:	1
        VmPeak:	  234192 kB           <-- here
        VmSize:	  169964 kB
        VmLck:	       0 kB
        VmPin:	       0 kB
        VmHWM:	   29528 kB
        VmRSS:	    6104 kB
        RssAnon:	    2756 kB
        RssFile:	    3348 kB
        RssShmem:	       0 kB
        VmData:	   19776 kB
        VmStk:	    1036 kB
        VmExe:	     784 kB
        VmLib:	    9532 kB
        VmPTE:	     116 kB
        VmSwap:	    2400 kB
        HugetlbPages:	       0 kB
        CoreDumping:	0
        THP_enabled:	1
        Threads:	1                     <-- and here
        SigQ:	1/62808
        SigPnd:	0000000000000000
        ShdPnd:	0000000000000000
        SigBlk:	7be3c0fe28014a03
        SigIgn:	0000000000001000
      
      And this is for kernel thread:
      
        $ head -20 /proc/2/status
        Name:	kthreadd
        Umask:	0000
        State:	S (sleeping)
        Tgid:	2
        Ngid:	0
        Pid:	2
        PPid:	0
        TracerPid:	0
        Uid:	0	0	0	0
        Gid:	0	0	0	0
        FDSize:	64
        Groups:
        NStgid:	2
        NSpid:	2
        NSpgid:	0
        NSsid:	0
        Threads:	1                     <-- here
        SigQ:	1/62808
        SigPnd:	0000000000000000
        ShdPnd:	0000000000000000
      Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
      Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Ian Rogers <irogers@google.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: https://lore.kernel.org/r/20210202090118.2008551-3-namhyung@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      c1b90795
    • Namhyung Kim's avatar
      perf tools: Use /proc/<PID>/task/<TID>/status for PERF_RECORD_ event synthesis · 30626e08
      Namhyung Kim authored
      To save memory usage, it needs to reduce the number of entries in the
      proc filesystem.  It's using /proc/<PID>/task directory to traverse
      threads in the process and then kernel creates /proc/<PID>/task/<TID>
      entries.
      
      After that it checks the thread info using the /proc/<TID>/status file
      rather than /proc/<PID>/task/<TID>/status.  As far as I can see, they
      are the same and contain all the info we need.
      
      Using the latter eliminates the unnecessary /proc/<TID> entry.  This can
      be useful especially a large number of threads are used in the system.
      In my experiment around 1KB of memory on average was saved for each
      thread (which is not a thread group leader).
      
      To do this, pass both pid and tid to perf_event_prepare_comm() if it
      knows them.  In case it doesn't know, passing 0 as pid will do the old
      way.
      Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
      Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Ian Rogers <irogers@google.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Link: https://lore.kernel.org/r/20210202090118.2008551-2-namhyung@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      30626e08
    • John Garry's avatar
      perf vendor events arm64: Reference common and uarch events for A76 · c3a9cdef
      John Garry authored
      Reduce duplication in the JSONs by referencing standard events from
      armv8-common-and-microarch.json
      
      In general the "PublicDescription" fields are not modified when somewhat
      significantly worded differently than the standard.
      
      Apart from that, description and names for events slightly different to
      standard are changed (to standard) for consistency.
      Signed-off-by: default avatarJohn Garry <john.garry@huawei.com>
      Acked-by: default avatarWill Deacon <will@kernel.org>
      Cc: James Clark <james.clark@arm.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Leo Yan <leo.yan@linaro.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
      Cc: Nakamura, Shunsuke/中村 俊介 <nakamura.shun@fujitsu.com>
      Cc: linux-arm-kernel@lists.infradead.org
      Cc: linuxarm@openeuler.org
      Link: https://lore.kernel.org/r/1611835236-34696-5-git-send-email-john.garry@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      c3a9cdef