Commit b889b4fb4cbe for kernel

commit b889b4fb4cbea3ca7eb9814075d6a51936394bd9
Author: Yipeng Zou <zouyipeng@huawei.com>
Date:   Fri Aug 18 09:32:26 2023 +0800

    selftests/ftrace: traceonoff_triggers: strip off names

    The func_traceonoff_triggers.tc sometimes goes to fail
    on my board, Kunpeng-920.

    [root@localhost]# ./ftracetest ./test.d/ftrace/func_traceonoff_triggers.tc -l fail.log
    === Ftrace unit tests ===
    [1] ftrace - test for function traceon/off triggers     [FAIL]
    [2] (instance)  ftrace - test for function traceon/off triggers [UNSUPPORTED]

    I look up the log, and it shows that the md5sum is different between csum1 and csum2.

    ++ cnt=611
    ++ sleep .1
    +++ cnt_trace
    +++ grep -v '^#' trace
    +++ wc -l
    ++ cnt2=611
    ++ '[' 611 -ne 611 ']'
    +++ cat tracing_on
    ++ on=0
    ++ '[' 0 '!=' 0 ']'
    +++ md5sum trace
    ++ csum1='76896aa74362fff66a6a5f3cf8a8a500  trace'
    ++ sleep .1
    +++ md5sum trace
    ++ csum2='ee8625a21c058818fc26e45c1ed3f6de  trace'
    ++ '[' '76896aa74362fff66a6a5f3cf8a8a500  trace' '!=' 'ee8625a21c058818fc26e45c1ed3f6de  trace' ']'
    ++ fail 'Tracing file is still changing'
    ++ echo Tracing file is still changing
    Tracing file is still changing
    ++ exit_fail
    ++ exit 1

    So I directly dump the trace file before md5sum, the diff shows that:

    [root@localhost]# diff trace_1.log trace_2.log -y --suppress-common-lines
    dockerd-12285   [036] d.... 18385.510290: sched_stat | <...>-12285   [036] d.... 18385.510290: sched_stat
    dockerd-12285   [036] d.... 18385.510291: sched_swit | <...>-12285   [036] d.... 18385.510291: sched_swit
    <...>-740       [044] d.... 18385.602859: sched_stat | kworker/44:1-740 [044] d.... 18385.602859: sched_stat
    <...>-740       [044] d.... 18385.602860: sched_swit | kworker/44:1-740 [044] d.... 18385.602860: sched_swit

    And we can see that <...> filed be filled with names.

    We can strip off the names there to fix that.

    After strip off the names:

    kworker/u257:0-12 [019] d..2.  2528.758910: sched_stat | -12 [019] d..2.  2528.758910: sched_stat_runtime: comm=k
    kworker/u257:0-12 [019] d..2.  2528.758912: sched_swit | -12 [019] d..2.  2528.758912: sched_switch: prev_comm=kw
    <idle>-0          [000] d.s5.  2528.762318: sched_waki | -0  [000] d.s5.  2528.762318: sched_waking: comm=sshd pi
    <idle>-0          [037] dNh2.  2528.762326: sched_wake | -0  [037] dNh2.  2528.762326: sched_wakeup: comm=sshd pi
    <idle>-0          [037] d..2.  2528.762334: sched_swit | -0  [037] d..2.  2528.762334: sched_switch: prev_comm=sw

    Link: https://lore.kernel.org/r/20230818013226.2182299-1-zouyipeng@huawei.com
    Fixes: d87b29179aa0 ("selftests: ftrace: Use md5sum to take less time of checking logs")
    Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org>
    Signed-off-by: Yipeng Zou <zouyipeng@huawei.com>
    Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
    Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
    Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc
index aee22289536b..1b57771dbfdf 100644
--- a/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc
+++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc
@@ -90,9 +90,10 @@ if [ $on != "0" ]; then
     fail "Tracing is not off"
 fi

-csum1=`md5sum trace`
+# Cannot rely on names being around as they are only cached, strip them
+csum1=`cat trace | sed -e 's/^ *[^ ]*\(-[0-9][0-9]*\)/\1/' | md5sum`
 sleep $SLEEP_TIME
-csum2=`md5sum trace`
+csum2=`cat trace | sed -e 's/^ *[^ ]*\(-[0-9][0-9]*\)/\1/' | md5sum`

 if [ "$csum1" != "$csum2" ]; then
     fail "Tracing file is still changing"