Commit Graph

291 Commits

Author SHA1 Message Date
Robert Marko
4341901f05 config: add ARM PMUv3 for kernel 6.6
Kernel 6.6 has moved the ARM PMUv3 driver to drivers/perf and now once
KERNEL_ARM_PMU is selected trying to build the kernel will stop with:
ARM PMUv3 support (ARM_PMUV3) [N/y/?] (NEW)

So, lets enable ARM_PMUV3 for ARMv7 and ARMv8 architectures if
KERNEL_PERF_EVENTS is selected.

Fixes: 
Link: https://github.com/openwrt/openwrt/pull/15469
Signed-off-by: Robert Marko <robimarko@gmail.com>
2024-05-14 13:23:57 +02:00
Weijie Gao
7fcb82665e loongarch64: new target
Add target for Loongson LoongArch64-based boards.

LoongArch is a new RISC ISA developed by Loongson. It's a bit like
MIPS or RISC-V. LoongArch includes both 32-bit and 64-bit versions
(LoongArch32/LoongArch64).

Loongson 3A5000 and 3A6000 are the two existing CPUs of LoongArch64
and is used for PC products. It's BIOS supports ACPI and UEFI-only
boot. These CPUs supports SMP and SMT.

At present only LoongArch64 is supported by linux kernel.

Toolchain requirement:
binutils >= 2.40
gcc >= 13.1

For details, please check the following links:
https://lwn.net/Articles/861951/
https://loongson.github.io/LoongArch-Documentation/README-EN.html

Signed-off-by: Weijie Gao <hackpascal@gmail.com>
2024-05-04 14:14:16 +08:00
Daniel Golle
918d81a3ea mediatek: increase size of the sdcard image to 512 MiB
Increasing the size of the rootfs_data filesystem has become a ever
repeating discussion and seems to be the most important thing for
users of the MediaTek-based BananaPi boards.

Using the whole remaining size of a microSD or the eMMC for rootfs_data
doesn't make sense for many reasons, but neither does the current
default of 104 MiB for the 'rootfs' partition size.

Increase the 'rootfs' partition size to 448 MiB which will result in
the sdcard image being exactly 512 MiB. Finding a microSD card smaller
than 512 MiB and still working could anyway be difficult in 2024.

That will allow users to install even bloatware written in Go or other
space-hungry languages while still leaving most of the space unallocated
for additional partitions or volumes to be used for persistent user
data.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
2024-05-02 14:58:31 +01:00
Daniel Golle
501ef81040 config: select KERNEL_WERROR if building with default GCC version
At the moment we have to manually follow the default GCC version
also in config/Config-kernel.in. This tends to be forgotten at GCC
version bumps (just happened when switching from version 12 to 13).
Instead, introduce a hidden Kconfig symbol which implies KERNEL_WERROR
in toolchain/gcc/Config.in where it is visible for developers changing
the default version.

Also remove the explicit default on BUILDBOT to avoid a circular
dependency and also because buildbots anyway implicitly always select
the default GCC version.

Reference: https://github.com/openwrt/openwrt/pull/15064
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
2024-04-08 01:40:15 +01:00
Jordan Woyak
f9f2426e39 config: Enable ext4 journaling by default.
Not having a journal by default is a major "gotcha".

Because openwrt does not fsck on boot, a power loss without journaling
can result in a dirty filesystem that openwrt will mount as read-only
which requires intervention to restore the router to working order.

Signed-off-by: Jordan Woyak <jordan.woyak@gmail.com>
2024-03-29 17:49:53 +01:00
Qingfang Deng
686cc58c10 kernel: support RISC-V PMU
Add RISC-V PMU config symbols and enable them for riscv64.

Signed-off-by: Qingfang Deng <dqfext@gmail.com>
2024-03-23 17:28:55 +01:00
Qingfang Deng
a646e4f697 kernel: enable KASAN option for more architectures
KASAN has supported more architectures, such as ARM, PPC32 and RISC-V 64.
Enable KASAN option for those architectures.

Signed-off-by: Qingfang Deng <dqfext@gmail.com>
2024-03-08 16:07:48 +08:00
Felix Fietkau
e772b75d5d broadcom-wl: remove package
Also remove remaining wireless extension support, since this package
was the only in-tree user of it

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2024-02-03 16:16:36 +01:00
Cedric DOURLENT
869f8b21e7 build: add option for building with stack-protector-all
The GCC option -fstack-protector-all is a security feature used to protect against stack-smashing attacks.
This option enhances the stack-smashing protection provided by -fstack-protector-strong.
-fstack-protector-all option applies stack protection to all functions, regardless of their characteristics.
While this offers the most comprehensive protection against stack-smashing attacks, it can significantly impact
the performance of the program because every function call includes additional checks for stack integrity.
This option can incur a performance penalty because of the extra checks added to every function call,
but it significantly enhances security, making it harder for attackers to exploit buffer overflows to execute arbitrary code.
It's particularly useful in scenarios where security is paramount and performance trade-offs are acceptable.

Signed-off-by: Cedric DOURLENT <cedric.dourlent@softathome.com>
2024-01-19 21:27:14 +01:00
Hauke Mehrtens
4211eab085 target: Make TARGET_SERIAL independent of GRUB configuration
GRUB_SERIAL is also used for the default serial on the target and not
only in grub. When no grub was build it was not available and the build
fails.

Rename GRUB_SERIAL to TARGET_SERIAL and make it always available on x86
and armsr targets.

Fixes: 
Fixes: b10768476f ("x86,armsr: interpolate GRUB_SERIAL into /etc/inittab")
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
2023-11-29 23:43:01 +01:00
Rafał Miłecki
4fb8e68bc4 kernel: provide better control & help for SLUB configuration
Allow selecting KERNEL_SLUB_DEBUG and KERNEL_SLUB_DEBUG_ON manually and
provide detailed help for both.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2023-11-09 21:23:01 +01:00
Petr Štetiar
d604a07225
build: add CycloneDX SBOM JSON support
CycloneDX is an open source standard developed by the OWASP foundation.
It supports a wide range of development ecosystems, a comprehensive set
of use cases, and focuses on automation, ease of adoption, and
progressive enhancement of SBOMs (Software Bill Of Materials) throughout
build pipelines.

So lets add support for CycloneDX SBOM for packages and images
manifests.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
2023-11-01 11:14:41 +00:00
Mathew McBride
76d4a7c84a kernel: default ARM_PMU on for armsr/armv8
CONFIG_ARM_PMU (Arm Performance Monitor Unit) is a requirement
to use KVM (virtualization) from Linux 5.11+, as the virtualised
guest has virtualized PMU access.

Signed-off-by: Mathew McBride <matt@traverse.com.au>
2023-08-15 15:55:00 +02:00
Zhen XIN
d2af5ab850 build: Add option KERNEL_KASAN_SW_TAGS and HW_TAGS
Currently KASAN is supported but only the generic one. SW-tag and HW-tag
based KASAN have less impact on memory footprint or performance, and are
worth supporting.

Add choice menu for software and hardware Tag-Based KASAN, in addition
to the generic one.

Signed-off-by: Zhen XIN <zhen.xin@nokia-sbell.com>
[Restructure commit message]
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
2023-08-10 23:09:37 +02:00
Tianling Shen
06e64f9b36 kernel: modules: add xdp-sockets-diag support
Support for PF_XDP sockets monitoring interface used by the ss tool.

Signed-off-by: Tianling Shen <cnsztl@immortalwrt.org>
2023-07-05 20:02:12 +02:00
Andre Heider
65a716bb95
config: add a knob to use the mold linker for packages
Building it requires gcc >= 10.2 or clang >= 12.

Using sstrip with its -z argument can produce non-working binaries, like
a segfaulting `getrandom`, so don't allow that combination.

Signed-off-by: Andre Heider <a.heider@gmail.com>
2023-07-04 20:25:40 +02:00
Andre Heider
d026b19cdc
build: replace SSTRIP_ARGS with SSTRIP_DISCARD_TRAILING_ZEROES
sstrip only has one functional arg. Make that a bool option, which can
easily depend on other knobs then.

This is required to be disabled for the mold linker.

Signed-off-by: Andre Heider <a.heider@gmail.com>
2023-07-04 20:25:40 +02:00
Petr Štetiar
ce8c639a6c
kernel: introduce KERNEL_WERROR config option
In commit b2d1eb717b ("generic: 5.15: enable Werror by default for
kernel compile") CONFIG_WERROR=y was enabled and all warnings/errors
reported with GCC 12 were fixed.

Keeping this in sync with past/future GCC versions is going to be uphill
battle, so lets introduce new KERNEL_WERROR config option, enable it by
default only for tested/known working combinations and on buildbots.

References: 
Signed-off-by: Petr Štetiar <ynezz@true.cz>
2023-07-04 07:14:22 +02:00
Robert Marko
f02f6aaa8d
ipq807x: rename target to qualcommax
Currently, ipq807x only covers Qualcomm IPQ807x SoC-s.
However, Qualcomm also has IPQ60xx and IPQ50xx SoC-s under the AX WiSoC-s
and they share a lot of stuff with IPQ807x, especially IPQ60xx so to avoid
duplicating kernel patches and everything lets make a common target with
per SoC subtargets.

Start doing that by renaming ipq807x to qualcommax so that dependencies
on ipq807x target can be updated.

Signed-off-by: Robert Marko <robimarko@gmail.com>
2023-06-16 11:11:08 +02:00
Mathew McBride
40ce6a7920
config: change references from armvirt to armsr
armvirt target has been renamed to armsr (Arm SystemReady),
so the config defaults need to be changed as well.

Signed-off-by: Mathew McBride <matt@traverse.com.au>
2023-06-10 21:30:20 +02:00
Mathew McBride
f899e0e024
build: enable vmdk/vmware images for arm64 target
This is useful for VMware's ARM64 products, e.g Fusion for M1/ARM Macs.

Signed-off-by: Mathew McBride <matt@traverse.com.au>
2023-06-02 11:36:19 +02:00
Mathew McBride
71e56b2ff1
build: use 128MiB as the boot/kernel partition size on armvirt target
The nominal partition type for EFI boot partitions is FAT32,
which has a minimum size of 32MiB on a 512-byte-sector block device.

To ensure that the boot partition is created as FAT32 set a size
well above this minimum.

A useful discussion about EFI partition sizes can be found here:
https://superuser.com/questions/1310927/what-is-the-absolute-minimum-size-a-uefi-system-partition-can-be

I have found 128MiB works pretty consistently across both
tools (mkfs.fat) and firmwares (EDKII)

Signed-off-by: Mathew McBride <matt@traverse.com.au>
2023-06-02 11:36:18 +02:00
Mathew McBride
8f29b1573d
grub2: enable EFI for armvirt
This adds a separate package for EFI on Arm SystemReady
compatible machines. 32-bit Arm UEFI is supported as well.

It is very similar to x86-64 EFI setup, without the
need for BIOS backward compatibility and slightly
different default modules.

Signed-off-by: Mathew McBride <matt@traverse.com.au>
2023-06-02 11:36:12 +02:00
Hauke Mehrtens
16a20512d8
kernel: Set CONFIG_FRAME_WARN depending on target
This set the CONFIG_FRAME_WARN option depending on some target settings.
It will use the default from the upstream kernel and not the hard coded
value of 1024 now.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
2023-06-02 11:19:32 +02:00
Tianling Shen
c07038da27 kernel: add MODULE_ALLOW_BTF_MISMATCH option
BTF mismatch can occur for a separately-built module even when the ABI
is otherwise compatible and nothing else would prevent successfully
loading. Add a new config to control how mismatches are handled. By
default, preserve the current behavior of refusing to load the
module. If MODULE_ALLOW_BTF_MISMATCH is enabled, load the module but
ignore its BTF information.

Signed-off-by: Tianling Shen <cnsztl@immortalwrt.org>
2023-05-18 16:17:52 +02:00
Nick Hainke
047361dee4
treewide: cleanup kernel symbol references
We only use 5.15 kernel. So remove all those unnecessary symbols
referencing 5.10 or 5.15 kernel.

Can be found with:
  git grep -E 'LINUX_5_1(0|5)'

Note that we remove the dependency from "sound-soc-chipdip-dac" instead
of removing the complete kernel package. The 5.15 version bump forgot to
delete the "@LINUX_5_10" dependency. The kernel package is still needed
in 5.15 kernel.

Signed-off-by: Nick Hainke <vincent@systemli.org>
2023-05-12 13:02:44 +02:00
Tony Ambardar
3d66f55161 kernel: improve handling of CONFIG_IO_URING
Kernel setting CONFIG_IO_URING supports high-performance I/O for file
access and servers, generally for more performant platforms, and adds
~45 KB to kernel sizes. The need for this on less "beefy" devices is
questionable, as is the size cost considering many platforms have kernel
size limits which require tricky repartitioning if outgrown. The size
cost is also large relative to the ~180 KB bump expected between major
OpenWRT kernel releases.

No OpenWrt packages have hard dependencies on this; samba4 and mariadb
can take advantage if available (+KERNEL_IO_URING:liburing) but
otherwise build and work fine.

Since CONFIG_IO_URING is already managed via the KERNEL_IO_URING setting
in Config-kernel.in (default Y), remove it from those target configs
which unconditionally enable it, and update the defaults to enable it
conditionally only on more powerful 64-bit x86 and arm devices. It may
still be manually enabled as needed for high-performance custom builds.

Signed-off-by: Tony Ambardar <itugrok@yahoo.com>
2023-05-03 10:26:17 -07:00
Andre Heider
9ea7019ffd
build: add a config knob to enable LTO for all packages
This enables LTO for all packages which haven't opted-out.

Signed-off-by: Andre Heider <a.heider@gmail.com>
2023-03-21 18:28:24 +01:00
Andre Heider
aef8bab9d7
build: add a config knob to enable gc-sections for all packages
This enables the linker's garbage collection for all packages which haven't
opted-out.

Signed-off-by: Andre Heider <a.heider@gmail.com>
2023-03-21 18:28:23 +01:00
Hauke Mehrtens
b844716158 kernel: Add CONFIG_KERNEL_HARDLOCKUP_DETECTOR
Make it possible to change the kernel configuration option
CONFIG_HARDLOCKUP_DETECTOR from OpenWrt.

Signed-off-by: Hauke Mehrtens <hmehrtens@maxlinear.com>
2023-03-19 18:44:46 +01:00
Stijn Tintel
4448b27930 kernel: set default for KERNEL_BPF_KPROBE_OVERRIDE
Without the default value this still causes a missing symbol. Disable by
default as it depends on FUNCTION_ERROR_INJECTION, which is disabled in
the generic config and we don't have a build symbol to enable that.

Fixes: 500c37c56f ("kernel: add missing symbol")
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
2023-03-05 18:36:01 +02:00
Prasun Maiti
522a60cd31 build: fix for sourcing targets image config installed via feeds
Sourcing of image/Config.in will not happen
When a target is installed from target/linux/feeds/

Signed-off-by: Prasun Maiti <prasunmaiti87@gmail.com>
Acked-by: Petr Štetiar <ynezz@true.cz>
2023-02-26 22:22:48 +01:00
Robert Marko
721206a1b1 kernel: set default values for ARM low level debugging symbols
Set default values for KERNEL_DEBUG_LL and KERNEL_DEBUG_LL_UART_NONE again
as both of these symbols are non visible if KERNEL_EARLY_PRINTK is not
selected and KConfig wont write their value to .config.

This usually is the intended behaviour, but in OpenWrt we are relying on
the KConfig to set these and disable the debug console settings that
multiple targets like mvebu have set in their kernel config.
This was the behaviour before removing all of the "default n" settings
as KConfig by default considers symbols disabled but they are not visible
anymore and thus their value is not set in .config and build system then
later does not override the values from target kernel config.

So, to restore the behaviour to the previous one lets a default value for
KERNEL_DEBUG_LL and KERNEL_DEBUG_LL_UART_NONE.

Fixes: 8bc72ea7be ("treewide: strip useless default n Kconfig lines")
Tested-by: Georgi Valkov <gvalkov@gmail.com>
Signed-off-by: Robert Marko <robimarko@gmail.com>
2023-02-08 16:21:05 +01:00
Tony Butler
8bc72ea7be treewide: strip useless default n Kconfig lines
Kconfig docs say:
> The default value deliberately defaults to 'n' in order to avoid
> bloating the build.

Apply this rule everywhere, to avoid more cloning of bad examples

Signed-off-by: Tony Butler <spudz76@gmail.com>
2023-02-03 12:50:15 +01:00
Felix Fietkau
d02d455678 kernel: make it possible for packages to select page pool support
Will be used by the next mt76 update

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2023-01-29 10:08:21 +01:00
Tony Butler
4a444e576f build: fix incomplete initramfs compression options
Requires: tools/lz4, tools/lzop

complete the wiring so that these options work:
* `CONFIG_KERNEL_INITRAMFS_COMPRESSION_LZO`
* `CONFIG_KERNEL_INITRAMFS_COMPRESSION_LZ4`

Signed-off-by: Tony Butler <spudz76@gmail.com>
[remove blocking dependencies for separate ramdisk, fix lzop options]
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
2023-01-17 00:16:35 +00:00
Robert Marko
b5f32064ed ipq807x: add Qualcomm Atheros IPQ807x target
Qualcomm Atheros IPQ807x is a modern WiSoC featuring:
* Quad Core ARMv8 Cortex A-53
	* @ 2.2 GHz (IPQ8072A/4A/6A/8A) Codename Hawkeye
	* @ 1.4 GHz (IPQ8070A/1A) Codename Acorn
* Dual Band simultaneaous IEEE 802.11ax
	* 5G: 8x8/80 or 4x4/160MHz (IPQ8074A/8A)
	* 5G: 4x4/80 or 2x2/160MHz (IPQ8071A/2A/6A)
	* 5G: 2x2/80MHz (IPQ8070A)
	* 2G: 4x4/40MHz (IPQ8072A/4A/6A/8A)
	* 2G: 2x2/40MHz (IPQ8070A/1A)
* 1x PSGMII via QCA8072/5 (Max 5x 1GbE ports)
* 2x SGMII/USXGMII (1/2.5/5/10 GbE) on Hawkeye
* 2x SGMII/USXGMII (1/2.5/5 GbE) on Acorn
* DDR3L/4 32/16 bit up to 2400MT/s
* SDIO 3.0/SD card 3.0/eMMC 5.1
* Dual USB 3.0
* One PCIe Gen2.1 and one PCIe Gen3.0 port (Single lane)
* Parallel NAND (ONFI)/LCD
* 6x QUP BLSP SPI/I2C/UART
* I2S, PCM, and TDMA
* HW PWM
* 1.8V configurable GPIO
* Companion PMP8074 PMIC via SPMI (GPIOS, RTC etc)

Note that only v2 SOC models aka the ones ending with A suffix are
supported, v1 models do not comply to the final 802.11ax and have
lower clocks, lack the Gen3 PCIe etc.

SoC itself has two UBI32 cores for the NSS offloading system, however
currently no offloading is supported.

Signed-off-by: Robert Marko <robimarko@gmail.com>
2023-01-16 12:42:23 +01:00
Tony Butler
6cee46def0 build: images: squashfs: add help, fix description
add help text for `TARGET_SQUASHFS_BLOCK_SIZE` to match the only valid
settings accepted by `mksquashfs4` ("block size not power of two or not
between 4096 and 1Mbyte") thus for this setting in "KB", the set:
  `4, 8, 16, 32, 64, 128, 256, 512, 1024`

replace `squashfs-lzma` with `squashfs` in the description for
`TARGET_ROOTFS_SQUASHFS` because it has various compressions, and not
just lzma as it did in the past

cosmetic change with no functional effect

Signed-off-by: Tony Butler <spudz76@gmail.com>
2022-12-06 23:12:14 +01:00
Tony Butler
7e83cdf3f7 build: config: cleanup impossible dependency logic
some config `depends on` lines contained outdated kernel version checks
that can no longer happen and had become non-operational; clean them up

cosmetic change with no functional effect

Signed-off-by: Tony Butler <spudz76@gmail.com>
2022-12-03 20:45:55 +01:00
Christian Marangi
901366ad66
Revert "build: fix for sourcing target image config a when target is being replaced"
This reverts commit ce1346a8fc.

Seems to cause buildbot compilation to fail and require more testing.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
2022-11-09 22:28:53 +01:00
Prasun Maiti
ce1346a8fc build: fix for sourcing target image config a when target is being replaced
Sourcing of image/Config.in will not happen
When a target is installed from target/linux/feeds/

Signed-off-by: Prasun Maiti <prasunmaiti87@gmail.com>
2022-11-09 20:47:43 +01:00
Christian Marangi
f17608ddca
scripts/download.pl: make the download tool configurable
Introduce a new option in the "Advanced configuration options" to
configure a custom download tool.

By declaring a string in "Use custom download tool" an user can force
what command to use to download package. With the string empty the
default tool used is curl, with wget as a fallback if not available.

download.pl supports 3 tools officially aria2c, curl and wget.
If one of the tool is used in this config, download.pl will use the
default args to make use of them.

If the provided string is different than aria2c, curl or wget, the command
is used as is and the download url will be appended at the end of such command.

While at it also tweak the tool selection logic and chose the tool only
once when the script is called and move aria2c specific variables in the
relevant section.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
2022-10-20 00:35:19 +02:00
Christian Marangi
ebabdff401
tools: add option BUILD_ALL_HOST_TOOLS to compile all host tools
Add option to compile all host tools even if not needed.
This can be useful to prepare a universal precompiled host tools
archive to use in another buildroot and speedup compilation.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
2022-09-30 22:26:54 +02:00
Felix Fietkau
6eeb5d4564 kernel: disable wireless extensions only when needed
They are only needed by a few very old drivers

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2022-09-22 15:26:58 +02:00
Hauke Mehrtens
9403810c02 toolchain: Select USE_SSTRIP with external musl toolchain
When we use the internal toolchain USE_SSTRIP will be selected by
default for musl libc and USE_STRIP when glibc is used. Do the same when
an external toolchain is used. USE_GLIBC will also be set for external
toolchain builds based on the EXTERNAL_TOOLCHAIN_LIBC_USE_GLIBC setting.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
2022-09-12 23:16:22 +02:00
Josh Roys
90c6e3aedf
scripts: always check certificates
Remove flags from wget and curl instructing them to ignore bad server
certificates. Although other mechanisms can protect against malicious
modifications of downloads, other vectors of attack may be available
to an adversary.

TLS certificate verification can be disabled by turning oof the
"Enable TLS certificate verification during package download" option
enabled by default in the "Global build settings" in "make menuconfig"

Signed-off-by: Josh Roys <roysjosh@gmail.com>
[ add additional info on how to disable this option ]
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
2022-09-10 15:24:22 +02:00
Thibaut VARÈNE
832e7b8172 build: always set CONFIG_IPV6
Disabling this build tunable breaks build and seems unrealistically
likely to be fixed.

This patch sets the related CONFIG to always true and removes the
config prompt, keeping the change minimal, and, should !CONFIG_IPV6 ever
be fixed, easy to revert.

Signed-off-by: Thibaut VARÈNE <hacks@slashdirt.org>
Acked-by: Stijn Tintel <stijn@linux-ipv6.be>
Acked-by: Paul Spooren <mail@aparcar.org>
Acked-by: Josef.Schlehofer <pepe.schlehofer@gmail.com>
Acked-by: Jo-Philipp Wich <jo@mein.io>
2022-08-20 21:41:03 +03:00
Florian Fainelli
e7ec2d7399 kernel: add KERNEL_DEBUG_VIRTUAL
This option allows turning on CONFIG_DEBUG_VIRTUAL which is useful to
debug incorrect uses of the virtual to physical and physical to virtual
translations functions.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
2022-07-07 15:07:16 -07:00
Rafał Miłecki
abc5b28db1 bcm53xx: use -falign-functions=32 for kernel compilation
Northstar SoCs have pretty small CPU caches and their performance is
heavily affected by cache hits & misses. It means that all kind of
random code changes can affect performance as they often reorganize
(change alignment & possibly reorder) kernel symbols.

It was discussed in ARM / net mailinglists:
1. ARM router NAT performance affected by random/unrelated commits [1] [2]
2. Optimizing kernel compilation / alignments for network performance [3] [4]

It seems that -falign-functions can be used as a partial workaround. It
doesn't solve all cases (e.g. documented watchdog one [5]) but it surely
helps with many of them.

A complete long term solution may be PGO (profile-guided optimization)
but it isn't available at this point.

[1] https://lkml.org/lkml/2019/5/21/349
[2] https://www.spinics.net/lists/linux-block/msg40624.html
[3] https://lore.kernel.org/linux-arm-kernel/066fc320-dc04-11a4-476e-b0d11f3b17e6@gmail.com/T/
[4] https://www.spinics.net/lists/netdev/msg816103.html
[5] http://lists.openwrt.org/pipermail/openwrt-devel/2022-July/038989.html

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2022-07-03 13:59:12 +02:00
Rafał Miłecki
907d7d7472 kernel: support setting extra CFLAGS for kernel compilation
They may be used e.g. to optimize kernel size or performance.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2022-06-20 22:17:38 +02:00