Commit ec07906b authored by Vincent Donnefort's avatar Vincent Donnefort Committed by Marc Zyngier
Browse files

tracing: selftests: Extend hotplug testing for trace remotes 



The hotplug testing only tries reading a trace remote buffer, loaded
before a CPU is offline. Extend this testing to cover:

  * A trace remote buffer loaded after a CPU is offline.
  * A trace remote buffer loaded before a CPU is online.

Because of these added test cases, move the hotplug testing into a
separate hotplug.tc file.

Acked-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: default avatarVincent Donnefort <vdonnefort@google.com>
Link: https://patch.msgid.link/20260401045100.3394299-3-vdonnefort@google.com


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent ce47b798

tools/testing/selftests/ftrace/test.d/remotes/functions

+15 −4
Original line number Diff line number Diff line
@@ -24,12 +24,21 @@ setup_remote_test() 


assert_loaded()

{

	grep -q "(loaded)" buffer_size_kb

	grep -q "(loaded)" buffer_size_kb || return 1

}



assert_unloaded()

{

	grep -q "(unloaded)" buffer_size_kb

	grep -q "(unloaded)" buffer_size_kb || return 1

}



reload_remote()

{

	echo 0 > tracing_on

	clear_trace

	assert_unloaded

	echo 1 > tracing_on

	assert_loaded

}



dump_trace_pipe()
@@ -79,10 +88,12 @@ get_cpu_ids() 
    sed -n 's/^processor\s*:\s*\([0-9]\+\).*/\1/p' /proc/cpuinfo

}



get_page_size() {

get_page_size()

{

    sed -ne 's/^.*data.*size:\([0-9][0-9]*\).*/\1/p' events/header_page

}



get_selftest_event_size() {

get_selftest_event_size()

{

    sed -ne 's/^.*field:.*;.*size:\([0-9][0-9]*\);.*/\1/p' events/*/selftest/format | awk '{s+=$1} END {print s}'

}

tools/testing/selftests/ftrace/test.d/remotes/hotplug.tc

0 → 100644
+88 −0
Original line number Diff line number Diff line 
#!/bin/sh

# SPDX-License-Identifier: GPL-2.0

# description: Test trace remote read with an offline CPU

# requires: remotes/test



. $TEST_DIR/remotes/functions



hotunplug_one_cpu()

{

	[ "$(get_cpu_ids | wc -l)" -ge 2 ] || return 1



	for cpu in $(get_cpu_ids); do

		echo 0 > /sys/devices/system/cpu/cpu$cpu/online || return 1

		break

	done



	echo $cpu

}



# Check non-consuming and consuming read

check_read()

{

    for i in $(seq 1 8); do

        echo $i > write_event

    done



    check_trace 1 8 trace



    output=$(dump_trace_pipe)

    check_trace 1 8 $output

    rm $output

}



test_hotplug()

{

    echo 0 > trace

    assert_loaded



    #

    # Test a trace buffer containing an offline CPU

    #



    cpu=$(hotunplug_one_cpu) || exit_unsupported

    trap "echo 1 > /sys/devices/system/cpu/cpu$cpu/online" EXIT



    check_read



    #

    # Test a trace buffer with a missing CPU

    #



    reload_remote



    check_read



    #

    # Test a trace buffer with a CPU added later

    #



    echo 1 > /sys/devices/system/cpu/cpu$cpu/online

    trap "" EXIT

    assert_loaded



    check_read



    # Test if the ring-buffer for the newly added CPU is both writable and

    # readable

    for i in $(seq 1 8); do

        taskset -c $cpu echo $i > write_event

    done



    cd per_cpu/cpu$cpu/



    check_trace 1 8 trace



    output=$(dump_trace_pipe)

    check_trace 1 8 $output

    rm $output



    cd -

}



if [ -z "$SOURCE_REMOTE_TEST" ]; then

    set -e



    setup_remote_test

    test_hotplug

fi

tools/testing/selftests/ftrace/test.d/remotes/hypervisor/hotplug.tc

0 → 100644
+11 −0
Original line number Diff line number Diff line 
#!/bin/sh

# SPDX-License-Identifier: GPL-2.0

# description: Test hypervisor trace read with an offline CPU

# requires: remotes/hypervisor/write_event



SOURCE_REMOTE_TEST=1

. $TEST_DIR/remotes/hotplug.tc



set -e

setup_remote "hypervisor"

test_hotplug

tools/testing/selftests/ftrace/test.d/remotes/trace.tc

+1 −26
Original line number Diff line number Diff line
@@ -58,11 +58,7 @@ test_trace() 
    #



    # Ensure the writer is not on the reader page by reloading the buffer

    echo 0 > tracing_on

    echo 0 > trace

    assert_unloaded

    echo 1 > tracing_on

    assert_loaded

    reload_remote



    # Ensure ring-buffer overflow by emitting events from the same CPU

    for cpu in $(get_cpu_ids); do
@@ -96,27 +92,6 @@ test_trace() 


        cd - > /dev/null

    done



    #

    # Test with hotplug

    #



    [ "$(get_cpu_ids | wc -l)" -ge 2 ] || return 0



    echo 0 > trace



    for cpu in $(get_cpu_ids); do

        echo 0 > /sys/devices/system/cpu/cpu$cpu/online || return 0

        break

    done



    for i in $(seq 1 8); do

        echo $i > write_event

    done



    check_trace 1 8 trace



    echo 1 > /sys/devices/system/cpu/cpu$cpu/online

}



if [ -z "$SOURCE_REMOTE_TEST" ]; then

tools/testing/selftests/ftrace/test.d/remotes/trace_pipe.tc

+0 −25
Original line number Diff line number Diff line
@@ -92,31 +92,6 @@ test_trace_pipe() 
        rm $output

        cd - > /dev/null

    done



    #

    # Test interaction with hotplug

    #



    [ "$(get_cpu_ids | wc -l)" -ge 2 ] || return 0



    echo 0 > trace



    for cpu in $(get_cpu_ids); do

        echo 0 > /sys/devices/system/cpu/cpu$cpu/online || return 0

        break

    done



    for i in $(seq 1 8); do

        echo $i > write_event

    done



    output=$(dump_trace_pipe)



    check_trace 1 8 $output



    rm $output



    echo 1 > /sys/devices/system/cpu/cpu$cpu/online

}



if [ -z "$SOURCE_REMOTE_TEST" ]; then