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Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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and remove the one off uncached definition for ARC
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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In the past I've refrained from doing this (at least 2 times) due to the
slight code bloat due to ABI implications of pte_t etc becoming struct
Per ARC ABI, functions return struct via memory and not through register
r0, even if the struct would fit in register(s)
- caller allocates space on stack and passes the address as first arg
(r0), shifting rest of args by one
- callee creates return struct in memory (referenced via r0)
This time around the code actually shrunk slightly (due to subtle
inlining heuristic effects), but still slightly inefficient due to
return values passed through memory. That however seems like a small
cost compared to maintenance burden given the impending new mmu support
for page walk etc
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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Don't pollute mmu.h and cache.h with ARC internal bootlog/setup
related functions. Move them aside to setup.h
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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This was used back in arc700 days when ASID allocator was fragile.
Not needed in last 5 years
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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MMU SCRATCH_DATA0 register is intended to cache task pgd. However in
ARC700 SMP port, it has to be repurposed for re-entrant interrupt
handling, while UP port doesn't. We currently handle these use-cases
using a fabricated #define which has usual issues of dependency nesting
and obvious ugliness.
So clean this up: for ARC700 don't use to cache pgd (even in UP) and do
the opposite for ARCv2.
And while here, switch to canonical pgd_offset().
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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There's no known/active customer using them with latest kernels anyways.
Removal helps cleanup code and remove the hack for
MMU_VER to MMU_V[3-4] conversion
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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There's no known/active customer using them with latest kernels anyways.
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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And move them out of cmpxchg.h to canonical atomic.h
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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It only makes sense to do this for the LLSC config
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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Existing code forces/assume args to type "long" which won't work in LP64
regime, so prepare code for that
Interestingly this should be a non functional change but I do see
some codegen changes
| bloat-o-meter vmlinux-cmpxchg-A vmlinux-cmpxchg-B
| add/remove: 0/0 grow/shrink: 17/12 up/down: 218/-150 (68)
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| Function old new delta
| rwsem_optimistic_spin 518 550 +32
| rwsem_down_write_slowpath 1244 1274 +30
| __do_sys_perf_event_open 2576 2600 +24
| down_read 192 200 +8
| __down_read 192 200 +8
...
| task_work_run 168 148 -20
| dma_fence_chain_walk.part 760 736 -24
| __genradix_ptr_alloc 674 646 -28
Total: Before=6187409, After=6187477, chg +0.00%
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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It gets in the way of cleaning things up and is a maintenance
pain-in-neck !
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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- !LLSC now only needs a single spinlock for atomics and bitops
- Some codegen changes (slight bloat) with generic bitops
1. code increase due to LD-check-atomic paradigm vs. unconditonal
atomic (but dirty'ing the cache line even if set already).
So despite increase, generic is right thing to do.
2. code decrease (but use of costlier instructions such as DIV vs.
shifts based math) due to signed arithmetic.
This needs to be revisited seperately.
arc:
static inline int test_bit(unsigned int nr, const volatile unsigned long *addr)
^^^^^^^^^^^^
generic:
static inline int test_bit(int nr, const volatile unsigned long *addr)
^^^
Link: https://lore.kernel.org/r/20180830135749.GA13005@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
[vgupta: wrote patch based on Will's poc, analysed codegen diffs]
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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The current ARC fetch/return atomics provide fully ordered semantics
only with 2 full barriers around the operation.
Instead implement them as relaxed variants without any barriers and
rely on generic code to generate the fully-ordered, acquire and release
varaints by adding the appropriate full barriers.
This helps elide some extra barriers in case of acquire/release/relaxed
calls.
bloat-o-meter for hsdk defconfig shows codegen improvements, although
numbers below inflated due to unrelated inlining heuristic changes
| bloat-o-meter vmlinux-643babe34fd7-non-relaxed vmlinux-45aa05cb44d7-relaxed
| add/remove: 2/5 grow/shrink: 42/1222 up/down: 4158/-14312 (-10154)
| Function old new delta
| ..
| sys_renameat 462 476 +14
| ip_mc_inc_group 424 436 +12
| do_read_cache_page 1882 1894 +12
| ..
| refcount_dec_and_mutex_lock 254 250 -4
| refcount_dec_and_lock_irqsave 258 254 -4
| refcount_dec_and_lock 254 250 -4
| ..
| tcp_v6_route_req 246 238 -8
| tcp_v4_destroy_sock 286 278 -8
| tcp_twsk_unique 352 344 -8
Link: https://lore.kernel.org/r/20180830144344.GW24142@hirez.programming.kicks-ass.net
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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This is a non-functional change since those wrappers are not
used in kernel sources at all.
Link: http://lists.infradead.org/pipermail/linux-snps-arc/2018-August/004246.html
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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!LLSC atomics use spinlock (SMP) or irq-disable (UP) to implement
criticla regions. UP atomic_set() however was "cheating" by not doing
any of that so and still being functional.
Remove this anomaly (primarily as cleanup for future code improvements)
given that this config is not worth hassle of special case code.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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Non functional change, to ease future addition/removal
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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0day bot reports a build error:
ERROR: modpost: "clear_user_page" [drivers/media/v4l2-core/videobuf-dma-sg.ko] undefined!
so export it in arch/arc/ to fix the build error.
In most ARCHes, clear_user_page() is a macro. OTOH, in a few
ARCHes it is a function and needs to be exported.
PowerPC exported it in 2004. It looks like nds32 and nios2
still need to have it exported.
Fixes: 4102b53392d63 ("ARC: [mm] Aliasing VIPT dcache support 2/4")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-snps-arc@lists.infradead.org
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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Some typos are found out by codespell tool:
./intc-compact.c:145: prioity ==> priority
./smp.c:286: recevier ==> receiver
./stacktrace.c:152 prelogue ==> prologue
Fix typos found by codespell.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Add -s option (strict mode) to merge_config.sh to make it fail when
any symbol is redefined.
- Show a warning if a different compiler is used for building external
modules.
- Infer --target from ARCH for CC=clang to let you cross-compile the
kernel without CROSS_COMPILE.
- Make the integrated assembler default (LLVM_IAS=1) for CC=clang.
- Add <linux/stdarg.h> to the kernel source instead of borrowing
<stdarg.h> from the compiler.
- Add Nick Desaulniers as a Kbuild reviewer.
- Drop stale cc-option tests.
- Fix the combination of CONFIG_TRIM_UNUSED_KSYMS and CONFIG_LTO_CLANG
to handle symbols in inline assembly.
- Show a warning if 'FORCE' is missing for if_changed rules.
- Various cleanups
* tag 'kbuild-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits)
kbuild: redo fake deps at include/ksym/*.h
kbuild: clean up objtool_args slightly
modpost: get the *.mod file path more simply
checkkconfigsymbols.py: Fix the '--ignore' option
kbuild: merge vmlinux_link() between ARCH=um and other architectures
kbuild: do not remove 'linux' link in scripts/link-vmlinux.sh
kbuild: merge vmlinux_link() between the ordinary link and Clang LTO
kbuild: remove stale *.symversions
kbuild: remove unused quiet_cmd_update_lto_symversions
gen_compile_commands: extract compiler command from a series of commands
x86: remove cc-option-yn test for -mtune=
arc: replace cc-option-yn uses with cc-option
s390: replace cc-option-yn uses with cc-option
ia64: move core-y in arch/ia64/Makefile to arch/ia64/Kbuild
sparc: move the install rule to arch/sparc/Makefile
security: remove unneeded subdir-$(CONFIG_...)
kbuild: sh: remove unused install script
kbuild: Fix 'no symbols' warning when CONFIG_TRIM_UNUSD_KSYMS=y
kbuild: Switch to 'f' variants of integrated assembler flag
kbuild: Shuffle blank line to improve comment meaning
...
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cc-option-yn can be replaced with cc-option. ie.
Checking for support:
ifeq ($(call cc-option-yn,$(FLAG)),y)
becomes:
ifneq ($(call cc-option,$(FLAG)),)
Checking for lack of support:
ifeq ($(call cc-option-yn,$(FLAG)),n)
becomes:
ifeq ($(call cc-option,$(FLAG)),)
This allows us to pursue removing cc-option-yn.
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic updates from Arnd Bergmann:
"The main content for 5.15 is a series that cleans up the handling of
strncpy_from_user() and strnlen_user(), removing a lot of slightly
incorrect versions of these in favor of the lib/strn*.c helpers that
implement these correctly and more efficiently.
The only architectures that retain a private version now are mips,
ia64, um and parisc. I had offered to convert those at all, but Thomas
Bogendoerfer wanted to keep the mips version for the moment until he
had a chance to do regression testing.
The branch also contains two patches for bitops and for ffs()"
* tag 'asm-generic-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
bitops/non-atomic: make @nr unsigned to avoid any DIV
asm-generic: ffs: Drop bogus reference to ffz location
asm-generic: reverse GENERIC_{STRNCPY_FROM,STRNLEN}_USER symbols
asm-generic: remove extra strn{cpy_from,len}_user declarations
asm-generic: uaccess: remove inline strncpy_from_user/strnlen_user
s390: use generic strncpy/strnlen from_user
microblaze: use generic strncpy/strnlen from_user
csky: use generic strncpy/strnlen from_user
arc: use generic strncpy/strnlen from_user
hexagon: use generic strncpy/strnlen from_user
h8300: remove stale strncpy_from_user
asm-generic/uaccess.h: remove __strncpy_from_user/__strnlen_user
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Most architectures do not need a custom implementation, and in most
cases the generic implementation is preferred, so change the polariy
on these Kconfig symbols to require architectures to select them when
they provide their own version.
The new name is CONFIG_ARCH_HAS_{STRNCPY_FROM,STRNLEN}_USER.
The remaining architectures at the moment are: ia64, mips, parisc,
um and xtensa. We should probably convert these as well, but
I was not sure how far to take this series. Thomas Bogendoerfer
had some concerns about converting mips but may still do some
more detailed measurements to see which version is better.
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: linux-xtensa@linux-xtensa.org
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Helge Deller <deller@gmx.de> # parisc
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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As these are now in asm-generic, it's no longer necessary to
declare them in the architecture.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Remove the arc implemenation of strncpy/strnlen and instead use the
generic versions. The arc version is fairly slow because it always does
byte accesses even for aligned data, and its checks for user_addr_max()
differ from the generic code.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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This is a preparation for changing over architectures to the
generic implementation one at a time. As there are no callers
of either __strncpy_from_user() or __strnlen_user(), fold these
into the strncpy_from_user() and strnlen_user() functions to make
each implementation independent of the others.
Many of these implementations have known bugs, but the intention
here is to not change behavior at all and stay compatible with
those bugs for the moment.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
"Updates to the interrupt core and driver subsystems:
Core changes:
- The usual set of small fixes and improvements all over the place,
but nothing stands out
MSI changes:
- Further consolidation of the PCI/MSI interrupt chip code
- Make MSI sysfs code independent of PCI/MSI and expose the MSI
interrupts of platform devices in the same way as PCI exposes them.
Driver changes:
- Support for ARM GICv3 EPPI partitions
- Treewide conversion to generic_handle_domain_irq() for all chained
interrupt controllers
- Conversion to bitmap_zalloc() throughout the irq chip drivers
- The usual set of small fixes and improvements"
* tag 'irq-core-2021-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
platform-msi: Add ABI to show msi_irqs of platform devices
genirq/msi: Move MSI sysfs handling from PCI to MSI core
genirq/cpuhotplug: Demote debug printk to KERN_DEBUG
irqchip/qcom-pdc: Trim unused levels of the interrupt hierarchy
irqdomain: Export irq_domain_disconnect_hierarchy()
irqchip/gic-v3: Fix priority comparison when non-secure priorities are used
irqchip/apple-aic: Fix irq_disable from within irq handlers
pinctrl/rockchip: drop the gpio related codes
gpio/rockchip: drop irq_gc_lock/irq_gc_unlock for irq set type
gpio/rockchip: support next version gpio controller
gpio/rockchip: use struct rockchip_gpio_regs for gpio controller
gpio/rockchip: add driver for rockchip gpio
dt-bindings: gpio: change items restriction of clock for rockchip,gpio-bank
pinctrl/rockchip: add pinctrl device to gpio bank struct
pinctrl/rockchip: separate struct rockchip_pin_bank to a head file
pinctrl/rockchip: always enable clock for gpio controller
genirq: Fix kernel doc indentation
EDAC/altera: Convert to generic_handle_domain_irq()
powerpc: Bulk conversion to generic_handle_domain_irq()
nios2: Bulk conversion to generic_handle_domain_irq()
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Wherever possible, replace constructs that match either
generic_handle_irq(irq_find_mapping()) or
generic_handle_irq(irq_linear_revmap()) to a single call to
generic_handle_domain_irq().
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
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FPU_STATUS register contains FP exception flags bits which are updated
by core as side-effect of FP instructions but can also be manually
wiggled such as by glibc C99 functions fe{raise,clear,test}except() etc.
To effect the update, the programming model requires OR'ing FWE
bit (31). This bit is write-only and RAZ, meaning it is effectively
auto-cleared after write and thus needs to be set everytime: which
is how glibc implements this.
However there's another usecase of FPU_STATUS update, at the time of
Linux task switch when incoming task value needs to be programmed into
the register. This was added as part of f45ba2bd6da0dc ("ARCv2:
fpu: preserve userspace fpu state") which missed OR'ing FWE bit,
meaning the new value is effectively not being written at all.
This patch remedies that.
Interestingly, this snafu was not caught in interm glibc testing as the
race window which relies on a specific exception bit to be set/clear is
really small specially when it nvolves context switch.
Fortunately this was caught by glibc's math/test-fenv-tls test which
repeatedly set/clear exception flags in a big loop, concurrently in main
program and also in a thread.
Fixes: https://github.com/foss-for-synopsys-dwc-arc-processors/linux/issues/54
Fixes: f45ba2bd6da0dc ("ARCv2: fpu: preserve userspace fpu state")
Cc: stable@vger.kernel.org #5.6+
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
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Enabling CONFIG_STACKDEPOT results in the following build error.
arc-elf-ld: lib/stackdepot.o: in function `filter_irq_stacks':
stackdepot.c:(.text+0x456): undefined reference to `__irqentry_text_start'
arc-elf-ld: stackdepot.c:(.text+0x456): undefined reference to `__irqentry_text_start'
arc-elf-ld: stackdepot.c:(.text+0x476): undefined reference to `__irqentry_text_end'
arc-elf-ld: stackdepot.c:(.text+0x476): undefined reference to `__irqentry_text_end'
arc-elf-ld: stackdepot.c:(.text+0x484): undefined reference to `__softirqentry_text_start'
arc-elf-ld: stackdepot.c:(.text+0x484): undefined reference to `__softirqentry_text_start'
arc-elf-ld: stackdepot.c:(.text+0x48c): undefined reference to `__softirqentry_text_end'
arc-elf-ld: stackdepot.c:(.text+0x48c): undefined reference to `__softirqentry_text_end'
Other architectures address this problem by adding IRQENTRY_TEXT and
SOFTIRQENTRY_TEXT to the text segment, so do the same here.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
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There is a spelling mistake and incorrect grammar in the Kconfig
text. Fix them.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
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Fix checkpatch warnings:
WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
Signed-off-by: Jinchao Wang <wjc@cdjrlc.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Increase the -falign-functions alignment for the debug option.
- Remove ugly libelf checks from the top Makefile.
- Make the silent build (-s) more silent.
- Re-compile the kernel if KBUILD_BUILD_TIMESTAMP is specified.
- Various script cleanups
* tag 'kbuild-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (27 commits)
scripts: add generic syscallnr.sh
scripts: check duplicated syscall number in syscall table
sparc: syscalls: use pattern rules to generate syscall headers
parisc: syscalls: use pattern rules to generate syscall headers
nds32: add arch/nds32/boot/.gitignore
kbuild: mkcompile_h: consider timestamp if KBUILD_BUILD_TIMESTAMP is set
kbuild: modpost: Explicitly warn about unprototyped symbols
kbuild: remove trailing slashes from $(KBUILD_EXTMOD)
kconfig.h: explain IS_MODULE(), IS_ENABLED()
kconfig: constify long_opts
scripts/setlocalversion: simplify the short version part
scripts/setlocalversion: factor out 12-chars hash construction
scripts/setlocalversion: add more comments to -dirty flag detection
scripts/setlocalversion: remove workaround for old make-kpkg
scripts/setlocalversion: remove mercurial, svn and git-svn supports
kbuild: clean up ${quiet} checks in shell scripts
kbuild: sink stdout from cmd for silent build
init: use $(call cmd,) for generating include/generated/compile.h
kbuild: merge scripts/mkmakefile to top Makefile
sh: move core-y in arch/sh/Makefile to arch/sh/Kbuild
...
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arch/$(SRCARCH)/Kbuild is useful for Makefile cleanups because you can
use the obj-y syntax.
Add an empty file if it is missing in arch/$(SRCARCH)/.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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Use setup_initial_init_mm() helper to simplify code.
Link: https://lkml.kernel.org/r/20210608083418.137226-3-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com> arch/arc]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge more updates from Andrew Morton:
"190 patches.
Subsystems affected by this patch series: mm (hugetlb, userfaultfd,
vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock,
migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap,
zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc,
core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs,
signals, exec, kcov, selftests, compress/decompress, and ipc"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits)
ipc/util.c: use binary search for max_idx
ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock
ipc: use kmalloc for msg_queue and shmid_kernel
ipc sem: use kvmalloc for sem_undo allocation
lib/decompressors: remove set but not used variabled 'level'
selftests/vm/pkeys: exercise x86 XSAVE init state
selftests/vm/pkeys: refill shadow register after implicit kernel write
selftests/vm/pkeys: handle negative sys_pkey_alloc() return code
selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random
kcov: add __no_sanitize_coverage to fix noinstr for all architectures
exec: remove checks in __register_bimfmt()
x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned
hfsplus: report create_date to kstat.btime
hfsplus: remove unnecessary oom message
nilfs2: remove redundant continue statement in a while-loop
kprobes: remove duplicated strong free_insn_page in x86 and s390
init: print out unknown kernel parameters
checkpatch: do not complain about positive return values starting with EPOLL
checkpatch: improve the indented label test
checkpatch: scripts/spdxcheck.py now requires python3
...
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Currently most platforms define pmd_pgtable() as pmd_page() duplicating
the same code all over. Instead just define a default value i.e
pmd_page() for pmd_pgtable() and let platforms override when required via
<asm/pgtable.h>. All the existing platform that override pmd_pgtable()
have been moved into their respective <asm/pgtable.h> header in order to
precede before the new generic definition. This makes it much cleaner
with reduced code.
Link: https://lkml.kernel.org/r/1623646133-20306-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Currently most platforms define FIRST_USER_ADDRESS as 0UL duplication the
same code all over. Instead just define a generic default value (i.e 0UL)
for FIRST_USER_ADDRESS and let the platforms override when required. This
makes it much cleaner with reduced code.
The default FIRST_USER_ADDRESS here would be skipped in <linux/pgtable.h>
when the given platform overrides its value via <asm/pgtable.h>.
Link: https://lkml.kernel.org/r/1620615725-24623-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Acked-by: Guo Ren <guoren@kernel.org> [csky]
Acked-by: Stafford Horne <shorne@gmail.com> [openrisc]
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> [RISC-V]
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge misc updates from Andrew Morton:
"191 patches.
Subsystems affected by this patch series: kthread, ia64, scripts,
ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab,
slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap,
mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization,
pagealloc, and memory-failure)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits)
mm,hwpoison: make get_hwpoison_page() call get_any_page()
mm,hwpoison: send SIGBUS with error virutal address
mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes
mm/page_alloc: allow high-order pages to be stored on the per-cpu lists
mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM
mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA
docs: remove description of DISCONTIGMEM
arch, mm: remove stale mentions of DISCONIGMEM
mm: remove CONFIG_DISCONTIGMEM
m68k: remove support for DISCONTIGMEM
arc: remove support for DISCONTIGMEM
arc: update comment about HIGHMEM implementation
alpha: remove DISCONTIGMEM and NUMA
mm/page_alloc: move free_the_page
mm/page_alloc: fix counting of managed_pages
mm/page_alloc: improve memmap_pages dbg msg
mm: drop SECTION_SHIFT in code comments
mm/page_alloc: introduce vm.percpu_pagelist_high_fraction
mm/page_alloc: limit the number of pages on PCP lists when reclaim is active
mm/page_alloc: scale the number of pages that are batch freed
...
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DISCONTIGMEM was replaced by FLATMEM with freeing of the unused memory map
in v5.11.
Remove the support for DISCONTIGMEM entirely.
Link: https://lkml.kernel.org/r/20210608091316.3622-4-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Arc does not use DISCONTIGMEM to implement high memory, update the comment
describing how high memory works to reflect this.
Link: https://lkml.kernel.org/r/20210608091316.3622-3-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Use vma_lookup() to find the VMA at a specific address. As vma_lookup()
will return NULL if the address is not within any VMA, the start address
no longer needs to be validated.
Link: https://lkml.kernel.org/r/20210521174745.2219620-4-Liam.Howlett@Oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler udpates from Ingo Molnar:
- Changes to core scheduling facilities:
- Add "Core Scheduling" via CONFIG_SCHED_CORE=y, which enables
coordinated scheduling across SMT siblings. This is a much
requested feature for cloud computing platforms, to allow the
flexible utilization of SMT siblings, without exposing untrusted
domains to information leaks & side channels, plus to ensure more
deterministic computing performance on SMT systems used by
heterogenous workloads.
There are new prctls to set core scheduling groups, which allows
more flexible management of workloads that can share siblings.
- Fix task->state access anti-patterns that may result in missed
wakeups and rename it to ->__state in the process to catch new
abuses.
- Load-balancing changes:
- Tweak newidle_balance for fair-sched, to improve 'memcache'-like
workloads.
- "Age" (decay) average idle time, to better track & improve
workloads such as 'tbench'.
- Fix & improve energy-aware (EAS) balancing logic & metrics.
- Fix & improve the uclamp metrics.
- Fix task migration (taskset) corner case on !CONFIG_CPUSET.
- Fix RT and deadline utilization tracking across policy changes
- Introduce a "burstable" CFS controller via cgroups, which allows
bursty CPU-bound workloads to borrow a bit against their future
quota to improve overall latencies & batching. Can be tweaked via
/sys/fs/cgroup/cpu/<X>/cpu.cfs_burst_us.
- Rework assymetric topology/capacity detection & handling.
- Scheduler statistics & tooling:
- Disable delayacct by default, but add a sysctl to enable it at
runtime if tooling needs it. Use static keys and other
optimizations to make it more palatable.
- Use sched_clock() in delayacct, instead of ktime_get_ns().
- Misc cleanups and fixes.
* tag 'sched-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
sched/doc: Update the CPU capacity asymmetry bits
sched/topology: Rework CPU capacity asymmetry detection
sched/core: Introduce SD_ASYM_CPUCAPACITY_FULL sched_domain flag
psi: Fix race between psi_trigger_create/destroy
sched/fair: Introduce the burstable CFS controller
sched/uclamp: Fix uclamp_tg_restrict()
sched/rt: Fix Deadline utilization tracking during policy change
sched/rt: Fix RT utilization tracking during policy change
sched: Change task_struct::state
sched,arch: Remove unused TASK_STATE offsets
sched,timer: Use __set_current_state()
sched: Add get_current_state()
sched,perf,kvm: Fix preemption condition
sched: Introduce task_is_running()
sched: Unbreak wakeups
sched/fair: Age the average idle time
sched/cpufreq: Consider reduced CPU capacity in energy calculation
sched/fair: Take thermal pressure into account while estimating energy
thermal/cpufreq_cooling: Update offline CPUs per-cpu thermal_pressure
sched/fair: Return early from update_tg_cfs_load() if delta == 0
...
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Replace a bunch of 'p->state == TASK_RUNNING' with a new helper:
task_is_running(p).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210611082838.222401495@infradead.org
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Signed-off-by: Ingo Molnar <mingo@kernel.org>
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As pointed out by commit
de9b8f5dcbd9 ("sched: Fix crash trying to dequeue/enqueue the idle thread")
init_idle() can and will be invoked more than once on the same idle
task. At boot time, it is invoked for the boot CPU thread by
sched_init(). Then smp_init() creates the threads for all the secondary
CPUs and invokes init_idle() on them.
As the hotplug machinery brings the secondaries to life, it will issue
calls to idle_thread_get(), which itself invokes init_idle() yet again.
In this case it's invoked twice more per secondary: at _cpu_up(), and at
bringup_cpu().
Given smp_init() already initializes the idle tasks for all *possible*
CPUs, no further initialization should be required. Now, removing
init_idle() from idle_thread_get() exposes some interesting expectations
with regards to the idle task's preempt_count: the secondary startup always
issues a preempt_disable(), requiring some reset of the preempt count to 0
between hot-unplug and hotplug, which is currently served by
idle_thread_get() -> idle_init().
Given the idle task is supposed to have preemption disabled once and never
see it re-enabled, it seems that what we actually want is to initialize its
preempt_count to PREEMPT_DISABLED and leave it there. Do that, and remove
init_idle() from idle_thread_get().
Secondary startups were patched via coccinelle:
@begone@
@@
-preempt_disable();
...
cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210512094636.2958515-1-valentin.schneider@arm.com
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