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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /hal/android/AndroidHeterogeneousCpuInfo.cpp
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'hal/android/AndroidHeterogeneousCpuInfo.cpp')
-rw-r--r--hal/android/AndroidHeterogeneousCpuInfo.cpp85
1 files changed, 85 insertions, 0 deletions
diff --git a/hal/android/AndroidHeterogeneousCpuInfo.cpp b/hal/android/AndroidHeterogeneousCpuInfo.cpp
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+++ b/hal/android/AndroidHeterogeneousCpuInfo.cpp
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#include "Hal.h"
+#include "HalLog.h"
+#include "HalTypes.h"
+
+#include "mozilla/BitSet.h"
+#include "mozilla/CheckedInt.h"
+#include "prsystem.h"
+#include <fstream>
+
+namespace mozilla::hal_impl {
+
+mozilla::Maybe<HeterogeneousCpuInfo> CreateHeterogeneousCpuInfo() {
+ CheckedInt<size_t> cpuCount = PR_GetNumberOfProcessors();
+ if (!cpuCount.isValid()) {
+ HAL_ERR("HeterogeneousCpuInfo: Failed to query processor count");
+ return Nothing();
+ }
+
+ if (cpuCount.value() > HeterogeneousCpuInfo::MAX_CPUS) {
+ HAL_ERR("HeterogeneousCpuInfo: Too many cpus");
+ return Nothing();
+ }
+
+ std::vector<std::pair<int, int>> cpu_freqs;
+ cpu_freqs.reserve(cpuCount.value());
+ for (size_t i = 0; i < cpuCount.value(); i++) {
+ std::stringstream freq_filename;
+ // On all devices tested, even with isolated content processes we do have
+ // permission to read this file. If, however, this function stops working
+ // one day, then this may be a good place to start investigating.
+ freq_filename << "/sys/devices/system/cpu/cpu" << i
+ << "/cpufreq/cpuinfo_max_freq";
+ std::ifstream ifs(freq_filename.str());
+ if (!ifs) {
+ HAL_ERR("HeterogeneousCpuInfo: Failed to open file %s",
+ freq_filename.str().c_str());
+ return Nothing();
+ }
+ int freq;
+ if (!(ifs >> freq)) {
+ HAL_ERR("HeterogeneousCpuInfo: Failed to parse file %s",
+ freq_filename.str().c_str());
+ return Nothing();
+ }
+ cpu_freqs.push_back(std::make_pair(i, freq));
+ }
+
+ std::sort(cpu_freqs.begin(), cpu_freqs.end(),
+ [](auto lhs, auto rhs) { return lhs.second < rhs.second; });
+
+ HeterogeneousCpuInfo info;
+ info.mTotalNumCpus = cpuCount.value();
+
+ int lowest_freq = cpu_freqs.front().second;
+ int highest_freq = cpu_freqs.back().second;
+ for (const auto& [cpu, freq] : cpu_freqs) {
+ if (freq == highest_freq) {
+ info.mBigCpus[cpu] = true;
+ } else if (freq == lowest_freq) {
+ info.mLittleCpus[cpu] = true;
+ } else {
+ info.mMediumCpus[cpu] = true;
+ }
+ }
+
+ HAL_LOG("HeterogeneousCpuInfo: little: %zu, med: %zu, big: %zu",
+ info.mLittleCpus.Count(), info.mMediumCpus.Count(),
+ info.mBigCpus.Count());
+
+ return Some(info);
+}
+
+const Maybe<HeterogeneousCpuInfo>& GetHeterogeneousCpuInfo() {
+ static const Maybe<HeterogeneousCpuInfo> cpuInfo =
+ CreateHeterogeneousCpuInfo();
+ return cpuInfo;
+}
+
+} // namespace mozilla::hal_impl