[PATCH v2 00/20] powerpc: Define eligible functions as __init
Nick Child
nnac123 at gmail.com
Fri Dec 17 09:00:15 AEDT 2021
Hello all,
This patchset focuses on redefining/declaring functions that could be
labeled with the macro `__init`. From my understanding, an
initialization function is one which is only needed during the initial
phases of booting, after which it's resources can be freed. I figure
that any function which is only called by other initialization
functions may also be labeled as an initialization function. There are
several (mostly static) functions which can and should be labeled as
`__init`. I created some scripts to help identify these functions. It
scans all functions defined in `arch/powerpc` and, if it is only called
by functions with the `__init` attribute, it will go on to adjust the
prototype and definition to include the `__init` declaration. This
patchset hopes to solve related issue #282:
https://github.com/linuxppc/issues/issues/282
Some notes about the scripts:
1. Trying to handle things like functions assigned to macros and
function pointers proved to be a bit too complicated to track. I
ended up just halting the investigation of these functions. In
the future, I would like to be able to attempt to `__init` them
but for now we leave them alone.
2. The proper syntax for adding the `__init` macro is followed as it
is defined in `include/linux/init.h`.
3. There are some odd looking functions that look something like:
`char *__init foo(...`. I have found that this happens in many
other places in the kernel source prior to running the scripts.
Additionally, after running the scripts. I have successfully
built all powerpc defconfigs without error. For these reasons, I
assume the odd syntax is valid but I am interested in other
opinions on this.
5. I have run my scripts on the Dec 14, 2021 `merge` branch
(specifically 798527287598)
After running my script for 3 rounds, they have identified about 250
functions so I tried to break the patches up into related platforms and
subdirectories. There are only two functions with a prototype outside
of `arch/powerpc`, these are `find_via_cuda` and `find_via_pmu`. I put
those in their own patch.
Other than building all the ppc defconfigs, I have tested the changes
by building kernels with and without the patches using defconfigs
ppc64le_guest, powernv and pseries_le. There were no size differences
reported in the boot logs. However, when using `readelf -t` we see the
following differences in the size of the .text section:
ppc64le_guest -> .text decreased in size by 12.8k, init.text unchanged
powernv -> .text decreased in size by 7.7k, init.text unchanged
pseries_le -> .text decreased in size by 9.6k, init.text increased 65.5k
I figured the size differences (or lack of) in .init.text might have
something to do with the requirement that the .init.text "section ends
on a page boundary", as described in
`arch/powerpc/kernel/vmlinux.lds.S`.
I am excited to say this is my first attempt at kernel development. I
know this patchset is in no way important but I figured it was a good
starting point. Please let me know if there is anything I am doing
wrong or if I can do anything to help meet the kernel contribution
guidelines.
Special thanks to Daniel Axtens for mentoring me and helping me get my
first patchset out!
Changes in v2:
- add `__init` in prototypes right before the funtion name instead of
at the end.
- respond to ./scripts/checkpatch feedback
- reference the related github issue in cover letter
- fix date in cover letter
- rebase onto latest `merge`
v1:
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=277093&state=
Nick Child (20):
powerpc/kernel: Add __init attribute to eligible functions
powerpc/lib: Add __init attribute to eligible functions
powerpc/mm: Add __init attribute to eligible functions
powerpc/perf: Add __init attribute to eligible functions
powerpc/sysdev: Add __init attribute to eligible functions
powerpc/xmon: Add __init attribute to eligible functions
powerpc/cell: Add __init attribute to eligible functions
powerpc/chrp: Add __init attribute to eligible functions
powerpc/pasemi: Add __init attribute to eligible functions
powerpc/powermac: Add __init attribute to eligible functions
powerpc/powernv: Add __init attribute to eligible functions
powerpc/pseries: Add __init attribute to eligible functions
powerpc/ps3: Add __init attribute to eligible functions
powerpc/4xx: Add __init attribute to eligible functions
powerpc/44x: Add __init attribute to eligible functions
powerpc/embedded6xx: Add __init attribute to eligible functions
powerpc/83xx: Add __init attribute to eligible functions
powerpc/85xx: Add __init attribute to eligible functions
powerpc/512x: Add __init attribute to eligible functions
cuda/pmu: Make find_via_cuda/pmu init functions
arch/powerpc/include/asm/book3s/64/mmu.h | 2 +-
arch/powerpc/include/asm/btext.h | 10 ++--
arch/powerpc/include/asm/cpm2.h | 6 +--
arch/powerpc/include/asm/cpuidle.h | 2 +-
arch/powerpc/include/asm/eeh.h | 2 +-
arch/powerpc/include/asm/fadump-internal.h | 6 +--
arch/powerpc/include/asm/hugetlb.h | 2 +-
arch/powerpc/include/asm/i8259.h | 2 +-
arch/powerpc/include/asm/iommu.h | 2 +-
arch/powerpc/include/asm/ipic.h | 2 +-
arch/powerpc/include/asm/kexec.h | 2 +-
arch/powerpc/include/asm/kvm_guest.h | 2 +-
arch/powerpc/include/asm/mmu_context.h | 2 +-
arch/powerpc/include/asm/mpic.h | 2 +-
arch/powerpc/include/asm/opal.h | 2 +-
arch/powerpc/include/asm/pci.h | 2 +-
arch/powerpc/include/asm/perf_event_server.h | 2 +-
arch/powerpc/include/asm/setup.h | 8 +--
arch/powerpc/include/asm/smu.h | 2 +-
arch/powerpc/include/asm/udbg.h | 10 ++--
arch/powerpc/include/asm/xics.h | 4 +-
arch/powerpc/include/asm/xmon.h | 2 +-
arch/powerpc/kernel/btext.c | 12 ++---
arch/powerpc/kernel/dt_cpu_ftrs.c | 2 +-
arch/powerpc/kernel/eeh_cache.c | 2 +-
arch/powerpc/kernel/fadump.c | 18 +++----
arch/powerpc/kernel/nvram_64.c | 6 +--
arch/powerpc/kernel/pci-common.c | 2 +-
arch/powerpc/kernel/pci_32.c | 4 +-
arch/powerpc/kernel/prom.c | 4 +-
arch/powerpc/kernel/prom_init.c | 12 ++---
arch/powerpc/kernel/rtasd.c | 6 +--
arch/powerpc/kernel/security.c | 4 +-
arch/powerpc/kernel/setup_64.c | 2 +-
arch/powerpc/kernel/smp.c | 5 +-
arch/powerpc/kernel/sysfs.c | 10 ++--
arch/powerpc/kernel/udbg_16550.c | 10 ++--
arch/powerpc/kexec/core.c | 2 +-
arch/powerpc/lib/code-patching.c | 2 +-
arch/powerpc/lib/feature-fixups.c | 26 +++++-----
arch/powerpc/mm/book3s32/mmu.c | 2 +-
arch/powerpc/mm/book3s64/hash_utils.c | 6 +--
arch/powerpc/mm/book3s64/hugetlbpage.c | 2 +-
arch/powerpc/mm/book3s64/mmu_context.c | 2 +-
arch/powerpc/mm/book3s64/pkeys.c | 2 +-
arch/powerpc/mm/book3s64/radix_pgtable.c | 4 +-
arch/powerpc/mm/nohash/44x.c | 4 +-
arch/powerpc/mm/nohash/fsl_book3e.c | 2 +-
arch/powerpc/mm/nohash/tlb.c | 4 +-
arch/powerpc/mm/numa.c | 6 +--
arch/powerpc/mm/ptdump/ptdump.c | 2 +-
arch/powerpc/perf/core-book3s.c | 2 +-
arch/powerpc/perf/generic-compat-pmu.c | 2 +-
arch/powerpc/perf/internal.h | 18 +++----
arch/powerpc/perf/power10-pmu.c | 2 +-
arch/powerpc/perf/power5+-pmu.c | 2 +-
arch/powerpc/perf/power5-pmu.c | 2 +-
arch/powerpc/perf/power6-pmu.c | 2 +-
arch/powerpc/perf/power7-pmu.c | 2 +-
arch/powerpc/perf/power8-pmu.c | 2 +-
arch/powerpc/perf/power9-pmu.c | 2 +-
arch/powerpc/perf/ppc970-pmu.c | 2 +-
arch/powerpc/platforms/44x/fsp2.c | 4 +-
arch/powerpc/platforms/4xx/cpm.c | 4 +-
arch/powerpc/platforms/4xx/pci.c | 2 +-
arch/powerpc/platforms/512x/clock-commonclk.c | 52 +++++++++----------
arch/powerpc/platforms/512x/mpc512x.h | 4 +-
arch/powerpc/platforms/512x/mpc512x_shared.c | 4 +-
arch/powerpc/platforms/83xx/km83xx.c | 2 +-
arch/powerpc/platforms/83xx/mpc834x_mds.c | 2 +-
arch/powerpc/platforms/83xx/mpc837x_mds.c | 2 +-
arch/powerpc/platforms/83xx/mpc837x_rdb.c | 2 +-
arch/powerpc/platforms/83xx/mpc83xx.h | 6 +--
arch/powerpc/platforms/83xx/usb.c | 6 +--
arch/powerpc/platforms/85xx/ge_imp3a.c | 2 +-
arch/powerpc/platforms/85xx/mpc85xx_cds.c | 2 +-
.../platforms/85xx/socrates_fpga_pic.c | 2 +-
.../platforms/85xx/socrates_fpga_pic.h | 2 +-
arch/powerpc/platforms/85xx/xes_mpc85xx.c | 4 +-
arch/powerpc/platforms/cell/cbe_regs.c | 2 +-
arch/powerpc/platforms/cell/iommu.c | 14 ++---
arch/powerpc/platforms/cell/spu_base.c | 6 +--
arch/powerpc/platforms/cell/spu_manage.c | 16 +++---
arch/powerpc/platforms/cell/spufs/inode.c | 2 +-
arch/powerpc/platforms/chrp/pegasos_eth.c | 2 +-
arch/powerpc/platforms/embedded6xx/hlwd-pic.c | 4 +-
arch/powerpc/platforms/embedded6xx/hlwd-pic.h | 2 +-
arch/powerpc/platforms/embedded6xx/holly.c | 2 +-
.../platforms/embedded6xx/usbgecko_udbg.c | 4 +-
arch/powerpc/platforms/embedded6xx/wii.c | 2 +-
arch/powerpc/platforms/pasemi/msi.c | 2 +-
arch/powerpc/platforms/pasemi/pasemi.h | 2 +-
arch/powerpc/platforms/pasemi/pci.c | 2 +-
arch/powerpc/platforms/pasemi/setup.c | 2 +-
arch/powerpc/platforms/powermac/feature.c | 2 +-
arch/powerpc/platforms/powermac/nvram.c | 2 +-
arch/powerpc/platforms/powermac/pfunc_base.c | 6 +--
arch/powerpc/platforms/powermac/setup.c | 6 +--
arch/powerpc/platforms/powermac/smp.c | 4 +-
arch/powerpc/platforms/powermac/udbg_scc.c | 2 +-
arch/powerpc/platforms/powernv/idle.c | 6 +--
arch/powerpc/platforms/powernv/opal-core.c | 6 +--
arch/powerpc/platforms/powernv/opal-fadump.c | 2 +-
arch/powerpc/platforms/powernv/opal-msglog.c | 4 +-
arch/powerpc/platforms/powernv/opal-power.c | 2 +-
.../powerpc/platforms/powernv/opal-powercap.c | 2 +-
arch/powerpc/platforms/powernv/opal-rtc.c | 2 +-
.../platforms/powernv/opal-sensor-groups.c | 4 +-
arch/powerpc/platforms/powernv/opal.c | 8 +--
arch/powerpc/platforms/powernv/pci-ioda.c | 4 +-
arch/powerpc/platforms/powernv/powernv.h | 4 +-
arch/powerpc/platforms/powernv/rng.c | 2 +-
arch/powerpc/platforms/powernv/setup.c | 6 +--
arch/powerpc/platforms/ps3/gelic_udbg.c | 2 +-
arch/powerpc/platforms/ps3/mm.c | 4 +-
arch/powerpc/platforms/ps3/os-area.c | 4 +-
arch/powerpc/platforms/ps3/platform.h | 14 ++---
arch/powerpc/platforms/ps3/repository.c | 20 +++----
arch/powerpc/platforms/ps3/smp.c | 2 +-
arch/powerpc/platforms/ps3/spu.c | 2 +-
.../powerpc/platforms/pseries/event_sources.c | 2 +-
arch/powerpc/platforms/pseries/iommu.c | 2 +-
arch/powerpc/platforms/pseries/lpar.c | 6 +--
arch/powerpc/platforms/pseries/pseries.h | 2 +-
arch/powerpc/platforms/pseries/rtas-fadump.c | 6 +--
arch/powerpc/platforms/pseries/setup.c | 4 +-
arch/powerpc/platforms/pseries/vas.c | 2 +-
arch/powerpc/platforms/pseries/vio.c | 6 +--
arch/powerpc/sysdev/cpm2.c | 6 +--
arch/powerpc/sysdev/dart_iommu.c | 2 +-
arch/powerpc/sysdev/fsl_mpic_err.c | 4 +-
arch/powerpc/sysdev/fsl_pci.c | 2 +-
arch/powerpc/sysdev/fsl_pci.h | 2 +-
arch/powerpc/sysdev/i8259.c | 2 +-
arch/powerpc/sysdev/ipic.c | 2 +-
arch/powerpc/sysdev/mpic.c | 2 +-
arch/powerpc/sysdev/mpic.h | 10 ++--
arch/powerpc/sysdev/mpic_msi.c | 6 +--
arch/powerpc/sysdev/mpic_timer.c | 6 +--
arch/powerpc/sysdev/mpic_u3msi.c | 2 +-
arch/powerpc/sysdev/tsi108_pci.c | 2 +-
arch/powerpc/sysdev/udbg_memcons.c | 2 +-
arch/powerpc/sysdev/xics/icp-hv.c | 2 +-
arch/powerpc/sysdev/xics/icp-opal.c | 2 +-
arch/powerpc/sysdev/xics/xics-common.c | 2 +-
arch/powerpc/sysdev/xive/native.c | 4 +-
arch/powerpc/sysdev/xive/spapr.c | 6 +--
arch/powerpc/xmon/xmon.c | 2 +-
include/linux/cuda.h | 2 +-
include/linux/pmu.h | 2 +-
150 files changed, 335 insertions(+), 334 deletions(-)
--
2.25.1
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