blob: 86968857ebea140b88709259321b0500ae93a401 [file] [log] [blame]
// Copyright 2019 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "chromeos/memory/kstaled.h"
#include "base/bind.h"
#include "base/feature_list.h"
#include "base/files/file_util.h"
#include "base/metrics/field_trial_params.h"
#include "base/strings/string_number_conversions.h"
#include "chromeos/dbus/dbus_thread_manager.h"
#include "chromeos/dbus/debug_daemon/debug_daemon_client.h"
namespace chromeos {
namespace {
constexpr char kKstaledRatioFile[] = "/sys/kernel/mm/kstaled/ratio";
// KernelSupportsKstaled will check if the kernel supports kstaled this is as
// easy as checking for the kstaled sysfs node.
bool KernelSupportsKstaled() {
static const bool supported =
base::PathExists(base::FilePath(kKstaledRatioFile));
return supported;
}
void OnRatioSet(bool success) {
if (!success) {
LOG(ERROR) << "Unable to configure kstaled";
return;
}
VLOG(1) << "Debugd configured kstaled with value: " << kKstaledRatio.Get();
}
} // namespace
const base::Feature kKstaled{"KstaledSwap", base::FEATURE_DISABLED_BY_DEFAULT};
const base::FeatureParam<int> kKstaledRatio = {&kKstaled, "KstaledRatio", 4};
// InitializeKstaled will attempt to configure kstaled with the experimental
// parameters for this user.
void InitializeKstaled() {
bool feature_enabled = base::FeatureList::IsEnabled(kKstaled);
if (!feature_enabled) {
VLOG(1) << "Kstaled is disabled";
return;
}
if (!KernelSupportsKstaled()) {
LOG(ERROR) << "Unable to configure kstaled: no kernel support";
return;
}
int feature_ratio = kKstaledRatio.Get();
if (feature_ratio <= 0 || feature_ratio > 255) {
LOG(ERROR) << "Configuring kstaled with a ratio of 0 disables the "
"feature, the valid range is 1-255.";
return;
}
chromeos::DebugDaemonClient* debugd_client =
chromeos::DBusThreadManager::Get()->GetDebugDaemonClient();
DCHECK(debugd_client);
debugd_client->SetKstaledRatio(static_cast<uint8_t>(feature_ratio),
base::BindOnce(&OnRatioSet));
}
} // namespace chromeos