Revert "Revert "Update `set_cpu_freq.sh` to allow restoring CPUs to a default config.""

Fixed to check that `online` exists before writing to it.

This reverts commit ee4aea45fa9f32ff4d49a0ea724f3df3cac3585e.

Change-Id: If4e6c5f9df0316676ce66fd6d33f26967e52bf2c

7 files changed, 155 insertions, 96 deletions

diff --git a/benchmarks/benchmarks_run_target.sh b/benchmarks/benchmarks_run_target.sh
index bda1aab1..30c2d2ef 100755
--- a/benchmarks/benchmarks_run_target.sh
+++ b/benchmarks/benchmarks_run_target.sh
@@ -193,14 +193,17 @@ run_all_benchmarks() {
   get_device_settings "${target_device}" "${local_path}/../devices/config" || exit 1
 
   if ${DEVICE_IS_BIG_LITTLE}; then
-    safe "${local_path}/../devices/set_cpu_freq.sh" --little
+    safe "${local_path}/../devices/set_cpu_freq.sh" --little --pin_freq
     run_benchmarks "$1" "${target_device}" "${LITTLE_CPUS_NAME}"
-    safe "${local_path}/../devices/set_cpu_freq.sh" --big
+    safe "${local_path}/../devices/set_cpu_freq.sh" --big --pin_freq
     run_benchmarks "$1" "${target_device}" "${BIG_CPUS_NAME}"
   else
-    safe "${local_path}/../devices/set_cpu_freq.sh"
+    safe "${local_path}/../devices/set_cpu_freq.sh" --all --pin_freq
     run_benchmarks "$1" "${target_device}" "${CPUS_NAME}"
   fi
+
+  # Be a good citizen and restore the CPUs configuration to defaults.
+  safe "${local_path}/../devices/set_cpu_freq.sh" --default
 }
 
 main() {
@@ -214,12 +217,6 @@ main() {
 
   start_timer "${target_timer_name}"
 
-  # We need to set up an android environment to have access to `adb` for the CPU
-  # config backup helpers.
-  setup_android_target "arm_krait-eng"
-  local -r backup_cpus_config_dir=$(mktemp -d)
-  backup_device_cpus_config "$backup_cpus_config_dir"
-
   for bits in 32 64; do
     if ! ${options["${bits}bit"]}; then
       log I "Skipping ${bits}bit benchmarks."
@@ -242,7 +239,6 @@ main() {
     run_all_benchmarks "${bits}"
   done
 
-  restore_device_cpus_config "$backup_cpus_config_dir"
   stop_timer "${target_timer_name}"
 
   log S "$0 Finished!"
diff --git a/devices/config/angler.sh b/devices/config/angler.sh
index f0f214f0..787407c8 100644
--- a/devices/config/angler.sh
+++ b/devices/config/angler.sh
@@ -2,14 +2,28 @@
 # Helper script used for setting the Nexus 6P frequency.
 
 # shellcheck disable=SC2034
+NUMBER_OF_CPUS=8
+# shellcheck disable=SC2034
 DEVICE_IS_BIG_LITTLE=true
 # shellcheck disable=SC2034
 LITTLE_CPUS=(0 1 2 3)
 # shellcheck disable=SC2034
 BIG_CPUS=(4 5 6 7)
 # shellcheck disable=SC2034
+CPUS=(0 1 2 3 4 5 6 7)
+# shellcheck disable=SC2034
 TARGET_FREQ=1248000
 # shellcheck disable=SC2034
 LITTLE_CPUS_NAME=a53
 # shellcheck disable=SC2034
 BIG_CPUS_NAME=a57
+
+# Default CPU config.
+# shellcheck disable=SC2034
+LITTLE_CPUS_DEFAULT_MIN_FREQ=384000
+# shellcheck disable=SC2034
+LITTLE_CPUS_DEFAULT_MAX_FREQ=1555200
+# shellcheck disable=SC2034
+BIG_CPUS_DEFAULT_MIN_FREQ=633600
+# shellcheck disable=SC2034
+BIG_CPUS_DEFAULT_MAX_FREQ=1958400
diff --git a/devices/config/bullhead.sh b/devices/config/bullhead.sh
index 48f43efe..85ceeb43 100644
--- a/devices/config/bullhead.sh
+++ b/devices/config/bullhead.sh
@@ -2,14 +2,28 @@
 # Helper script used for setting the Nexus 5X frequency.
 
 # shellcheck disable=SC2034
+NUMBER_OF_CPUS=6
+# shellcheck disable=SC2034
 DEVICE_IS_BIG_LITTLE=true
 # shellcheck disable=SC2034
 LITTLE_CPUS=(0 1 2 3)
 # shellcheck disable=SC2034
 BIG_CPUS=(4 5)
 # shellcheck disable=SC2034
+CPUS=(0 1 2 3 4 5)
+# shellcheck disable=SC2034
 TARGET_FREQ=1248000
 # shellcheck disable=SC2034
 LITTLE_CPUS_NAME=a53
 # shellcheck disable=SC2034
 BIG_CPUS_NAME=a57
+
+# Default CPU config.
+# shellcheck disable=SC2034
+LITTLE_CPUS_DEFAULT_MIN_FREQ=384000
+# shellcheck disable=SC2034
+LITTLE_CPUS_DEFAULT_MAX_FREQ=1440000
+# shellcheck disable=SC2034
+BIG_CPUS_DEFAULT_MIN_FREQ=633600
+# shellcheck disable=SC2034
+BIG_CPUS_DEFAULT_MAX_FREQ=1824000
diff --git a/devices/config/flounder.sh b/devices/config/flounder.sh
index 5610ca13..5442fe6e 100644
--- a/devices/config/flounder.sh
+++ b/devices/config/flounder.sh
@@ -2,6 +2,8 @@
 # Helper script used for setting the Nexus 9 frequency.
 
 # shellcheck disable=SC2034
+NUMBER_OF_CPUS=2
+# shellcheck disable=SC2034
 DEVICE_IS_BIG_LITTLE=false
 # shellcheck disable=SC2034
 CPUS=(0 1)
@@ -9,3 +11,9 @@ CPUS=(0 1)
 TARGET_FREQ=1224000
 # shellcheck disable=SC2034
 CPUS_NAME=denver
+
+# Default CPU config.
+# shellcheck disable=SC2034
+CPUS_DEFAULT_MIN_FREQ=510000
+# shellcheck disable=SC2034
+CPUS_DEFAULT_MAX_FREQ=2460750
diff --git a/devices/cpu_freq_utils.sh b/devices/cpu_freq_utils.sh
index d5ed5c39..2c52d3a1 100644
--- a/devices/cpu_freq_utils.sh
+++ b/devices/cpu_freq_utils.sh
@@ -37,15 +37,24 @@ set_state_cpus() {
 
   local output new_status
   for cpu; do
-    # adb shell does not report return status properly, so at least check
-    # that no unexpected message was printed.
-    output=$(safe adb_shell_strip "echo ${state} > ${sys_cpu_path}/cpu${cpu}/online")
-    # If the kernel refuses to do the operation, the operation might fail
-    # without any message printed, check that the new status is what we expect.
-    new_status=$(safe adb_shell_strip "cat ${sys_cpu_path}/cpu${cpu}/online")
-    if [[ ${output} || ${new_status} != ${state} ]]; then
-      log E "Failed to set CPU ${cpu} to state ${state}: ${output}"
-      return 1
+    local online_file="${sys_cpu_path}/cpu${cpu}/online"
+    # Check whether the CPU has an associated `online` file.
+    if [[ $(safe adb_shell_strip "[[ -f ${online_file} ]] && echo y || echo n") == "n" ]]; then
+      # Only raise an error if we were trying to disable CPU.
+      if [[ $state -eq 0 ]]; then
+        log E "Could not write to $online_file"
+      fi
+    else
+      # adb shell does not report return status properly, so at least check
+      # that no unexpected message was printed.
+      output=$(safe adb_shell_strip "echo ${state} > $online_file")
+      # If the kernel refuses to do the operation, the operation might fail
+      # without any message printed, check that the new status is what we expect.
+      new_status=$(safe adb_shell_strip "cat $online_file")
+      if [[ ${output} || ${new_status} != ${state} ]]; then
+        log E "Failed to set CPU ${cpu} to state ${state}: ${output}"
+        return 1
+      fi
     fi
   done
 
@@ -130,40 +139,47 @@ get_device_settings() {
   safe source "${cpu_freq_script}"
 }
 
-# Arguments:
-#   ${1} - backup directory
-backup_device_cpus_config() {
-  local -r backup_dir="${1}"
-  for remote_cpu_path in $(adb_shell_strip echo "$sys_cpu_path/cpu*"); do
-    if [[ $remote_cpu_path =~ .*cpu([0-9]+)$ ]]; then
-      local cpu_index=${BASH_REMATCH[1]}
-      local local_cpu_path="$backup_dir/cpu$cpu_index"
-      safe mkdir -p "$local_cpu_path/cpufreq"
-      adb pull "$remote_cpu_path/online" "$local_cpu_path"
-      adb pull "$remote_cpu_path/cpufreq/scaling_governor" "$local_cpu_path/cpufreq/"
-      adb pull "$remote_cpu_path/cpufreq/scaling_setspeed" "$local_cpu_path/cpufreq/"
-    fi
+#   ${1}   - max frequency
+#   ${2}   - min frequency
+#   ${1-#} - CPU indexes
+configure_cpus_to_interactive() {
+  local -r max_freq=$1
+  local -r min_freq=$2
+  shift 2
+
+  local output=
+  for cpu; do
+    output+=$(safe adb_shell_strip "echo interactive > \
+      ${sys_cpu_path}/cpu${cpu}/cpufreq/scaling_governor")
+    # `scaling_max_freq` must be set before `scaling_min_freq`. See
+    # https://www.kernel.org/doc/Documentation/cpu-freq/user-guide.txt.
+    output+=$(safe adb_shell_strip "echo $max_freq > \
+      ${sys_cpu_path}/cpu${cpu}/cpufreq/scaling_max_freq")
+    output+=$(safe adb_shell_strip "echo $min_freq > \
+      ${sys_cpu_path}/cpu${cpu}/cpufreq/scaling_min_freq")
   done
+
+  if [[ ${output} ]]; then
+    log E "${output}"
+    return 1
+  else
+    return 0
+  fi
 }
 
+set_default_cpu_config() {
+  validate_cpus "$@" || return 1
 
-# Arguments:
-#   $1 - backup directory
-restore_device_cpus_config() {
-  local -r backup_dir="${1}"
-  for local_cpu_path in "$backup_dir"/*; do
-    local cpu_index=${local_cpu_path#${backup_dir}/cpu}
-    local remote_cpu_path="$sys_cpu_path/cpu$cpu_index"
-    # Note that we do not use `safe` for `online` and `scaling_setspeed`,
-    # because attempting to set those to their current value raises an error.
-    adb shell "echo \"$(cat "$local_cpu_path/online")\" > $remote_cpu_path/online"
-    if [[ -f "$local_cpu_path/cpufreq/scaling_governor" ]]; then
-      safe adb shell "echo \"$(cat "$local_cpu_path/cpufreq/scaling_governor")\" > $remote_cpu_path/cpufreq/scaling_governor"
-    fi
-    local freq=$(cat "$local_cpu_path/cpufreq/scaling_setspeed")
-    if [[ "$freq" =~ ^[0-9]+$ ]]; then
-      adb shell "echo \"$freq\" > $remote_cpu_path/cpufreq/scaling_setspeed"
-    fi
-  done
-  rm -rf "$backup_dir"
+  if ${DEVICE_IS_BIG_LITTLE}; then
+    safe enable_cpus "${BIG_CPUS[@]}"
+    safe enable_cpus "${LITTLE_CPUS[@]}"
+    safe configure_cpus_to_interactive \
+      "$BIG_CPUS_DEFAULT_MAX_FREQ" "$BIG_CPUS_DEFAULT_MIN_FREQ" "${BIG_CPUS[@]}"
+    safe configure_cpus_to_interactive \
+      "$LITTLE_CPUS_DEFAULT_MAX_FREQ" "$LITTLE_CPUS_DEFAULT_MIN_FREQ" "${LITTLE_CPUS[@]}"
+  else
+    safe enable_cpus "${CPUS[@]}"
+    safe configure_cpus_to_interactive \
+      "$CPUS_DEFAULT_MAX_FREQ" "$CPUS_DEFAULT_MIN_FREQ" "${CPUS[@]}"
+  fi
 }
diff --git a/devices/set_cpu_freq.sh b/devices/set_cpu_freq.sh
index 97abc580..f4709357 100755
--- a/devices/set_cpu_freq.sh
+++ b/devices/set_cpu_freq.sh
@@ -11,13 +11,14 @@ declare -A options
 target_device=
 
 init_options() {
-  options["big"]="false"
-  options["little"]="false"
+  options["cpus"]="all"
+  options["pin_freq"]="false"
+  options["default"]="false"
 }
 
 validate_options() {
-  if ${options["big"]} && ${options["little"]}; then
-    log E "Both --big and --little set. You need to only use one of these clusters at a time."
+  if ${options["default"]} && ( ${options["pin_freq"]} || [[ "${options["cpus"]}" != "all" ]] ); then
+    log E "The option \`--default\` is incompatible with \`--pin_freq\`, \`--big\`, and \`--little\`  options."
     exit 1
   fi
 }
@@ -25,31 +26,19 @@ validate_options() {
 usage() {
   log I "$0"
   log I "This script should be used for frequency scaling your device."
-  log I "The script expects a 64bit flounder (Nexus 9) or bullhead (Nexus 5X) connected."
   log I " -h|--help       - help"
   log I " -v|--verbose    - verbose"
   log I "-------------------------------------------"
-  log I "CPU clusters to be turned on and scaled:"
-  log I " --big           - Big cluster in a big.LITTLE SoC."
-  log I " --little        - Little cluster in a big.LITTLE SoC."
+  log I " --all           - Enable all CPUs (default)."
+  log I " --big           - Enable only the big cluster in a big.LITTLE SoC."
+  log I " --little        - Enable only the little cluster in a big.LITTLE SoC."
+  log I ""
+  log I " --pin_freq      - Pin the frequency of enabled cores."
+  log I " --default       - Restore the CPUs to the default configuration."
   log I ""
-  log I "Note: For SoCs with a single cluster none of the options above need to be specified."
   log I "-------------------------------------------"
 }
 
-set_option() {
-  local current_option=${1#"--"}
-  # shellcheck disable=SC2144
-  # shellcheck disable=SC2102
-  if [[ -v options[${current_option}] ]]; then
-    options[${current_option}]="true"
-  else
-    # There might be something wrong with the option parser since this option
-    # does not have a default.
-    abort
-  fi
-}
-
 arguments_parser() {
   init_options
   while [[ $# -gt 0 ]]; do
@@ -61,8 +50,14 @@ arguments_parser() {
         usage
         exit 0
         ;;
-      --big|--little)
-        set_option "$1"
+      --all|--big|--little)
+        options["cpus"]=${1#--}
+        ;;
+      --pin_freq)
+        options["pin_freq"]="true"
+        ;;
+      --default)
+        options["default"]="true"
         ;;
       *)
         log E "Invalid option: $1"
@@ -80,27 +75,37 @@ print_freq() {
 }
 
 set_device_freq() {
-  if ${DEVICE_IS_BIG_LITTLE}; then
-    if ${options["little"]}; then
-      log I "Setting cpu freq for the little cluster (freq = $(print_freq))."
-      safe enable_cpus "${LITTLE_CPUS[@]}"
-      safe disable_cpus "${BIG_CPUS[@]}"
-      safe set_freq_cpus "${TARGET_FREQ}" "${LITTLE_CPUS[@]}"
-    elif ${options["big"]}; then
-      log I "Setting cpu freq for the big cluster (freq = $(print_freq))."
-      safe enable_cpus "${BIG_CPUS[@]}"
-      safe disable_cpus "${LITTLE_CPUS[@]}"
-      safe set_freq_cpus "${TARGET_FREQ}" "${BIG_CPUS[@]}"
-    else
-      log E "Device ${target_device} is big.LITTLE, please specify a cluster."
-    fi
-  else
-    if ! ${options["big"]} && ! ${options["little"]}; then
-      log I "Setting cpu freq for the single cluster (freq = $(print_freq))."
-      safe set_freq_cpus "${TARGET_FREQ}" "${CPUS[@]}"
-    else
-      log E "Device ${target_device} is single-cluster, do not specify a cluster."
-    fi
+  if ! ${DEVICE_IS_BIG_LITTLE} && [[ ${options["cpus"]} != "all" ]]; then
+    log E "Device ${target_device} is single-cluster, do not use \`--big\` or \`little\` options."
+  fi
+
+  if ${options["default"]}; then
+    log I "Restoring CPUs configuration to defaults."
+    set_default_cpu_config
+    exit 0
+  fi
+
+  local -a cpus_to_configure
+
+  if [[ ${options["cpus"]} == "all" ]]; then
+    log I "Enabling all CPUs."
+    cpus_to_configure=("${CPUS[@]}")
+    safe enable_cpus "${cpus_to_configure[@]}"
+  elif [[ ${options["cpus"]} == "big" ]]; then
+    log I "Enabling only the big cluster."
+    safe enable_cpus "${BIG_CPUS[@]}"
+    safe disable_cpus "${LITTLE_CPUS[@]}"
+    cpus_to_configure=("${BIG_CPUS[@]}")
+  elif [[ ${options["cpus"]} == "little" ]]; then
+    log I "Enabling only the little cluster."
+    safe enable_cpus "${LITTLE_CPUS[@]}"
+    safe disable_cpus "${BIG_CPUS[@]}"
+    cpus_to_configure=("${LITTLE_CPUS[@]}")
+  fi
+
+  if ${options["pin_freq"]}; then
+    log I "Pinning the frequency."
+    safe set_freq_cpus "${TARGET_FREQ}" "${cpus_to_configure[@]}"
   fi
 }
 
diff --git a/tests/test_art_target.sh b/tests/test_art_target.sh
index 5733e7f6..49bd65ef 100755
--- a/tests/test_art_target.sh
+++ b/tests/test_art_target.sh
@@ -275,6 +275,10 @@ build_target() {
   end_section "build_target_$1" "$?"
 }
 
+configure_cpus() {
+  safe "${local_path}/../devices/set_cpu_freq.sh" --default
+}
+
 device_setup() {
   start_section "device_setup_$1"
   # Get adb root - needed otherwise device_cleanup() would fail.
@@ -407,6 +411,8 @@ main() {
     # Build target.
     build_target "${bits}"
 
+    configure_cpus
+
     # Setup & sync device.
     device_setup "${bits}"
     device_cleanup "${bits}"