blob: 8295518fb7adb1f861394e835fedc7de42d4d939 [file] [log] [blame]
# Copyright 2020 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
import("//build/zbi/kernel_cmdline.gni")
# This serves as an anchor point. By expressing a dependency on
# //boards/kernel_cmdline, build arguments declared in this file
# (e.g. pmm_checker_from_board) are brought into scope.
group("kernel_cmdline") {
}
kernel_cmdline("serial-legacy") {
args = [ "kernel.serial=legacy" ]
deps = [ "//build/validate:non_production_tag" ]
}
kernel_cmdline("disable-blobfs-compression") {
args = [ "blobfs.write-compression-algorithm=UNCOMPRESSED" ]
deps = [ "//build/validate:non_production_tag" ]
}
kernel_cmdline("pmm-checker") {
args = [
# Enable PMM checker to detect certain kinds of buffer overrun and
# use-after-free bugs.
"kernel.pmm-checker.enable=true",
# Use a small fill size to minimize performance impact. In practice,
# corruption tends to happen at the start of a page so filling/checking only
# the first 16 bytes provides decent coverage without sacrificing
# performance.
"kernel.pmm-checker.fill-size=16",
]
}
declare_args() {
# Used to control whether board definitions include PMM checker options.
pmm_checker_from_board = true
}
group("pmm-checker-from-board") {
if (pmm_checker_from_board) {
deps = [ ":pmm-checker" ]
}
}
kernel_cmdline("toulouse") {
args = [
# Fuchsia does not have a deterministic ordering for bringing up PCI devices, so the
# /dev/class/ethernet/xxx paths have no well-defined mapping to the ports on the front of the
# device.
# In order for netbooting and loglistener to work, we need to let netsvc know which path corresponds
# to the left-most ethernet port.
"kernel.serial=legacy",
"netsvc.interface=/dev/sys/platform/pci/00:1f.6/e1000/ethernet",
]
}
# This collects settings not specific to any particular machine that are
# recommended to minimize unintended effects on timing data. Note that this
# does not (as yet) include settings that may reduce overall performance, which
# x64-reduced-perf-variation (below) does (see x64-reduced-perf-variation.gni).
group("reduced-perf-variation") {
deps = [
":disable-page-scanner",
":quiet-early-boot",
]
}
# This collects settings not specific to any particular machine that are
# recommended to make the system's performance highly representative of a
# production setup.
group("perf-realistic") {
deps = [ ":quiet-early-boot" ]
}
kernel_cmdline("quiet-early-boot") {
args = [
# Disable serial console printing during early boot, a phase during which
# UART communication is single-threaded and synchronous. In production,
# the serial console will be disabled, and so early boot benchmarks that
# include this work is sensibly avoided.
"kernel.phys.verbose=false",
]
}
kernel_cmdline("disable-page-scanner") {
args = [
# Disable page scanning in all its forms. Page scanning is intended to
# provide a memory benefit to final systems, but the operation of the
# scanner and its unpredictable de-duplication or eviction of memory in use
# by benchmarks could cause noticeable variation.
"kernel.page-scanner.start-at-boot=false",
"kernel.page-scanner.zero-page-scans-per-second=0",
"kernel.page-scanner.enable-eviction=false",
]
}
kernel_cmdline("x64-reduced-perf-variation") {
deps = [ ":reduced-perf-variation" ]
args = [
# Disable Intel Turbo Boost. Turbo Boost provides a significant speed-up to
# many workloads, but — because CPU frequencies vary based on previous work,
# work in other cores, system temperature, etc — makes performance of systems
# less predictable. We prefer stability in our performance comparison
# benchmarks.
"kernel.x86.turbo=false",
# Set the Intel HWP performance profile to be "stable", trying to keep the
# CPU clock rate stable. With turbo boost disabled, this has only a small
# effect, but helps ensure that wake ups from idle are fixed.
"kernel.x86.hwp_policy=stable-performance",
# Disable hyper-threading. Hyper-threading reduces predictability of
# benchmarks, because the performance of a thread is significantly affected
# by other threads on the core.
"kernel.smp.ht=false",
# Disable spectre mitigations. Spectre mitigations have significant
# performance impact, but are currently only carried out on a subset of the
# NUC fleet. This means that different devices have significantly different
# performance characteristics, meaning that benchmark results vary
# significantly based on the device running it.
#
# TODO(fxbug.dev/33161): Ideally, we should load microcode during Zircon boot,
# which should bring all devices to the same patch level, removing the
# performance differences when spectre mitigations are in place.
"kernel.x86.disable_spec_mitigations=true",
]
}
kernel_cmdline("gce") {
args = [ "kernel.serial=legacy" ]
}
kernel_cmdline("vim3") {
deps = [ ":pmm-checker-from-board" ]
args = [
# Prefer using the built-in NIC to the CDC-ether interface.
"netsvc.interface=/dev/dwmac/dwmac/Designware-MAC/ethernet",
]
}
kernel_cmdline("chromebook-x64") {
deps = [ ":pmm-checker-from-board" ]
args = [
# Depthcharge will fill this in.
"zvb.boot-partition-uuid=%U",
]
}