From 3bfde48aceec7b73b8fe74e5c75fad0f795e67d6 Mon Sep 17 00:00:00 2001 From: Olivier Dion Date: Tue, 14 Feb 2023 14:35:34 -0500 Subject: [PATCH] Fix: Wrong assumption about possible CPUs MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit cpuset is not necessary contiguous. Thus, we need to parse /sys/devices/system/cpu/posssible correctly. Also, the `get_exposed_cpus_list' utility functions is required for taskset-ting on the correct CPUs available to the test environment. Change-Id: I062ce8d311ff0e8c4b757fe6f36387e3007cfa27 Signed-off-by: Olivier Dion Signed-off-by: Jérémie Galarneau --- tests/regression/tools/snapshots/ust_test | 10 ++-- tests/utils/utils.sh | 64 ++++++++++++++++++----- 2 files changed, 56 insertions(+), 18 deletions(-) diff --git a/tests/regression/tools/snapshots/ust_test b/tests/regression/tools/snapshots/ust_test index 26cfbf88e..d1ba07071 100755 --- a/tests/regression/tools/snapshots/ust_test +++ b/tests/regression/tools/snapshots/ust_test @@ -298,14 +298,15 @@ function test_ust_local_snapshot_small_overwrite_buffers () function test_ust_local_snapshot_max_size () { local possible_cpus - local online_cpus + local cpus_list local subbuf_size local subbuf_count local snapshot_max_size local channel_max_size_per_cpu + IFS=" " read -r -a cpus_list <<< "$(get_exposed_cpus_list)" + possible_cpus=$(get_possible_cpus_count) - online_cpus=$(conf_proc_count) subbuf_size=$(getconf PAGE_SIZE) subbuf_count=8 snapshot_max_size=$((subbuf_size*possible_cpus)) @@ -325,9 +326,10 @@ function test_ust_local_snapshot_max_size () # Fill all ring-buffers of the channel; assuming event size of at least one # byte - for cpu in $(seq "$online_cpus"); + for cpu in "${cpus_list[@]}"; do - taskset --cpu-list $((cpu-1)) "$TESTAPP_BIN" \ + diag "setting affinity to $cpu" + taskset --cpu-list "$cpu" "$TESTAPP_BIN" \ --iter "$channel_max_size_per_cpu" done diag "Filled channel ring-buffers" diff --git a/tests/utils/utils.sh b/tests/utils/utils.sh index 78bee0c63..a6f9a8b6c 100644 --- a/tests/utils/utils.sh +++ b/tests/utils/utils.sh @@ -217,33 +217,69 @@ function randstring() # Helpers for get_possible_cpus. function get_possible_cpus_count_from_sysfs_possible_mask() { - local max_possible_cpu_id=$(cut -d '-' -f 2 < /sys/devices/system/cpu/possible) - echo $((max_possible_cpu_id+1)) + local max_possible_cpu_id + + # The Awk script extracts the highest CPU id from the possible CPU + # mask. Assuming a numerical order, a field separator '-' and a record + # separator ','. The last value parsed is the highest id. + if [ -f /sys/devices/system/cpu/possible ]; then + max_possible_cpu_id=$(awk -F '-' 'BEGIN { RS = ","} { last = $NF } END { printf("%d\n", last) }' \ + /sys/devices/system/cpu/possible) + echo "$((max_possible_cpu_id+1))" + else + echo "0" + fi } +# This is a fallback if the possible CPU mask is not available. This will not +# take into account unplugged CPUs. function get_max_cpus_count_from_sysfs_cpu_directories() { - local max_possible_cpu_id= \ - $(find /sys/devices/system/cpu/ -mindepth 1 -maxdepth 1 -regex ".+cpu[0-9]+" | \ - sed -e 's/cpu//g' | \ - awk -F '/' '{ if ($NF > N) N = $NF } END { print N }') - echo $((max_possible_cpu_id+1)) + local max_possible_cpu_id=0 + local current_cpu_id + + for i in /sys/devices/system/cpu/cpu[0-9]*; do + current_cpu_id="${i#/sys/devices/system/cpu/cpu}" + if [ "$current_cpu_id" -gt "$max_possible_cpu_id" ]; then + max_possible_cpu_id="$current_cpu_id" + fi + done + + echo "$((max_possible_cpu_id+1))" } # Return the number of possible CPUs. function get_possible_cpus_count() { - local possible_cpus_count=$(get_possible_cpus_count_from_sysfs_possible_mask) + local possible_cpus_count + possible_cpus_count=$(get_possible_cpus_count_from_sysfs_possible_mask) - if [ $? -ne 0 ]; then + if [ "$possible_cpus_count" -eq "0" ]; then + local configured_cpus_count + configured_cpus_count=$(getconf _NPROCESSORS_CONF) possible_cpus_count=$(get_max_cpus_count_from_sysfs_cpu_directories) - local configured_cpus_count=$(getconf _NPROCESSORS_CONF) - possible_cpus_count=$(($configured_cpus_count > $possible_cpus_count \ - ? $configured_cpus_count \ - : $possible_cpus_count)) + possible_cpus_count=$((configured_cpus_count > possible_cpus_count \ + ? configured_cpus_count \ + : possible_cpus_count)) fi - echo $possible_cpus_count + echo "$possible_cpus_count" +} + +# Return the list of exposed CPU. +# +# NOTE! Use it like so: +# +# IFS=" " read -r -a VARIABLE <<< "$(get_exposed_cpus_list)" +function get_exposed_cpus_list() +{ + local list=() + + for i in /sys/devices/system/cpu/cpu[0-9]*; do + list+=("${i#/sys/devices/system/cpu/cpu}") + done + + echo "${list[@]}" } # Return the number of _configured_ CPUs. -- 2.34.1