linux/lib
Linus Torvalds 5d272dd1b3 cpumask: limit FORCE_NR_CPUS to just the UP case
Hardcoding the number of CPUs at compile time does improve code
generation, but if you get it wrong the result will be confusion.

We already limited this earlier to only "experts" (see commit
fe5759d5bf "cpumask: limit visibility of FORCE_NR_CPUS"), but with
distro kernel configs often having EXPERT enabled, that turns out to not
be much of a limit.

To quote the philosophers at Disney: "Everyone can be an expert. And
when everyone's an expert, no one will be".

There's a runtime warning if you then set nr_cpus to anything but the
forced number, but apparently that can be ignored too [1] and by then
it's pretty much too late anyway.

If we had some real way to limit this to "embedded only", maybe it would
be worth it, but let's see if anybody even notices that the option is
gone.  We need to simplify kernel configuration anyway.

Link: https://lore.kernel.org/all/20240618105036.208a8860@rorschach.local.home/ [1]
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Paul McKenney <paulmck@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-06-18 09:00:04 -07:00
..
842
crypto crypto: lib - implement library version of AES in CFB mode 2024-05-09 22:30:51 +03:00
dim lib: Allow for the DIM library to be modular 2024-05-07 16:42:45 -07:00
fonts fbdev fixes and cleanups for 6.9-rc1: 2024-03-22 10:09:08 -07:00
kunit kunit: bail out early in __kunit_test_suites_init() if there are no suites to test 2024-05-06 14:22:02 -06:00
lz4
lzo
math bitmap: introduce generic optimized bitmap_size() 2024-04-01 10:49:28 +01:00
pldmfw
raid6 lib/raid6: use CC_FLAGS_FPU for NEON CFLAGS 2024-05-19 14:36:18 -07:00
reed_solomon
test_fortify
vdso vdso: Fix powerpc build U64_MAX undeclared error 2024-04-09 12:35:19 +02:00
xz
zlib_deflate
zlib_dfltcc
zlib_inflate
zstd
.gitignore
alloc_tag.c lib/alloc_tag: do not register sysctl interface when CONFIG_SYSCTL=n 2024-06-15 10:43:05 -07:00
argv_split.c
ashldi3.c
ashrdi3.c
asn1_decoder.c
asn1_encoder.c
assoc_array.c
atomic64_test.c
atomic64.c
audit.c
base64.c
bcd.c
bch.c
bitfield_kunit.c
bitmap-str.c
bitmap.c
bitrev.c
bootconfig-data.S
bootconfig.c bootconfig: Fix the kerneldoc of _xbc_exit() 2024-04-18 05:01:32 +09:00
bsearch.c
btree.c
bucket_locks.c
bug.c
build_OID_registry lib/build_OID_registry: don't mention the full path of the script in output 2024-04-25 21:07:01 -07:00
buildid.c vmlinux: Avoid weak reference to notes section 2024-05-02 19:48:26 +09:00
bust_spinlocks.c
check_signature.c
checksum_kunit.c lib: checksum: hide unused expected_csum_ipv6_magic[] 2024-04-08 11:03:05 +01:00
checksum.c
closure.c closures: closure_sync_timeout() 2024-05-08 17:29:22 -04:00
clz_ctz.c
clz_tab.c
cmdline_kunit.c
cmdline.c
cmpdi2.c
cmpxchg-emu.c lib: Add one-byte emulation function 2024-04-09 22:06:00 -07:00
codetag.c lib: add memory allocations report in show_mem() 2024-04-25 20:55:57 -07:00
compat_audit.c
cpu_rmap.c
cpumask_kunit.c
cpumask.c
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c
crc4.c
crc7.c
crc8.c
crc16.c
crc32.c
crc32defs.h
crc32test.c
crc64-rocksoft.c
crc64.c
ctype.c
debug_info.c
debug_locks.c
debugobjects.c
dec_and_lock.c
decompress_bunzip2.c
decompress_inflate.c
decompress_unlz4.c
decompress_unlzma.c
decompress_unlzo.c
decompress_unxz.c
decompress_unzstd.c
decompress.c
devmem_is_allowed.c
devres.c devres: don't use "proxy" headers 2024-04-25 21:07:06 -07:00
dhry_1.c
dhry_2.c
dhry_run.c
dhry.h
digsig.c
dump_stack.c
dynamic_debug.c dyndbg: fix old BUG_ON in >control parser 2024-04-30 09:20:48 +02:00
dynamic_queue_limits.c net: dqs: make struct dql more cache efficient 2024-04-15 11:19:53 -07:00
earlycpio.c
errname.c
error-inject.c
errseq.c
extable.c
fault-inject-usercopy.c
fault-inject.c
fdt_addresses.c
fdt_empty_tree.c
fdt_ro.c
fdt_rw.c
fdt_strerror.c
fdt_sw.c
fdt_wip.c
fdt.c
find_bit_benchmark.c
find_bit.c bitmap patches for 6.10 2024-05-21 15:29:01 -07:00
flex_proportions.c
fortify_kunit.c mm/util: Swap kmemdup_array() arguments 2024-06-06 08:55:20 -07:00
fw_table.c
gen_crc32table.c
gen_crc64table.c
genalloc.c
generic-radix-tree.c
glob.c
globtest.c
group_cpus.c
hashtable_test.c
hexdump.c
hweight.c
idr.c
inflate.c
interval_tree_test.c
interval_tree.c
iomap_copy.c s390: Stop using weak symbols for __iowrite64_copy() 2024-04-22 17:11:20 -03:00
iomap.c
iommu-helper.c
iov_iter.c
irq_poll.c
irq_regs.c
is_signed_type_kunit.c
is_single_threaded.c
kasprintf.c
Kconfig cpumask: limit FORCE_NR_CPUS to just the UP case 2024-06-18 09:00:04 -07:00
Kconfig.debug - A series ("kbuild: enable more warnings by default") from Arnd 2024-05-22 18:59:29 -07:00
Kconfig.kasan
Kconfig.kcsan
Kconfig.kfence
Kconfig.kgdb kgdb: add HAS_IOPORT dependency 2024-04-25 21:07:05 -07:00
Kconfig.kmsan
Kconfig.ubsan ubsan: Restore dependency on ARCH_HAS_UBSAN 2024-05-18 13:46:10 -07:00
kfifo.c TTY/Serial changes for 6.10-rc1 2024-05-22 11:53:02 -07:00
klist.c
kobject_uevent.c
kobject.c
kstrtox.c
kstrtox.h
kunit_iov_iter.c kunit: Fix KUNIT_SUCCESS() calls in iov_iter tests 2024-05-06 14:22:02 -06:00
libcrc32c.c
linear_ranges.c
list_debug.c
list_sort.c
list-test.c
llist.c
locking-selftest-hardirq.h
locking-selftest-mutex.h
locking-selftest-rlock-hardirq.h
locking-selftest-rlock-softirq.h
locking-selftest-rlock.h
locking-selftest-rsem.h
locking-selftest-rtmutex.h
locking-selftest-softirq.h
locking-selftest-spin-hardirq.h
locking-selftest-spin-softirq.h
locking-selftest-spin.h
locking-selftest-wlock-hardirq.h
locking-selftest-wlock-softirq.h
locking-selftest-wlock.h
locking-selftest-wsem.h
locking-selftest.c
lockref.c
logic_iomem.c
logic_pio.c
lru_cache.c
lshrdi3.c
lwq.c
Makefile selftests/fpu: allow building on other architectures 2024-05-19 14:36:20 -07:00
maple_tree.c maple_tree: fix mas_empty_area_rev() null pointer dereference 2024-05-05 17:28:05 -07:00
memcat_p.c
memcpy_kunit.c string_kunit: Move strtomem KUnit test to string_kunit.c 2024-04-24 09:02:34 -07:00
memory-notifier-error-inject.c
memregion.c
memweight.c
muldi3.c
net_utils.c
netdev-notifier-error-inject.c
nlattr.c
nmi_backtrace.c
notifier-error-inject.c
notifier-error-inject.h
objagg.c
objpool.c objpool: cache nr_possible_cpus() and avoid caching nr_cpu_ids 2024-05-01 23:18:48 +09:00
of-reconfig-notifier-error-inject.c
oid_registry.c
once.c
overflow_kunit.c kunit/overflow: Adjust for __counted_by with DEFINE_RAW_FLEX() 2024-06-10 12:00:04 -07:00
packing.c
parman.c
parser.c
percpu_counter.c
percpu_test.c
percpu-refcount.c
plist.c
pm-notifier-error-inject.c
polynomial.c
radix-tree.c
radix-tree.h
random32.c
ratelimit.c
rbtree_test.c
rbtree.c
rcuref.c
ref_tracker.c
refcount.c
rhashtable.c rhashtable: plumb through alloc tag 2024-04-25 20:55:57 -07:00
sbitmap.c sbitmap: use READ_ONCE to access map->word 2024-04-26 07:40:28 -06:00
scatterlist.c Fix a potential infinite loop in extract_user_to_sg() 2024-04-26 12:35:57 -07:00
seq_buf.c
sg_pool.c
sg_split.c
siphash_kunit.c
siphash.c
slub_kunit.c mm/slub, kunit: Use inverted data to corrupt kmem cache 2024-04-04 16:08:10 +02:00
smp_processor_id.c
sort.c
stackdepot.c stackdepot: use gfp_nested_mask() instead of open coded masking 2024-05-19 14:40:44 -07:00
stackinit_kunit.c
stmp_device.c
string_helpers_kunit.c
string_helpers.c
string_kunit.c string_kunit: Move strtomem KUnit test to string_kunit.c 2024-04-24 09:02:34 -07:00
string.c
strncpy_from_user.c
strnlen_user.c
syscall.c
test_bitmap.c bitmap patches for 6.10 2024-05-21 15:29:01 -07:00
test_bitops.c lib/test_bitops: Add benchmark test for fns() 2024-05-09 09:25:08 -07:00
test_bits.c
test_blackhole_dev.c
test_bpf.c bpf, tests: Fix typos in comments 2024-04-16 17:22:18 +02:00
test_debug_virtual.c
test_dynamic_debug.c
test_firmware.c
test_fprobe.c
test_fpu_glue.c selftests/fpu: allow building on other architectures 2024-05-19 14:36:20 -07:00
test_fpu_impl.c selftests/fpu: move FP code to a separate translation unit 2024-05-19 14:36:20 -07:00
test_fpu.h selftests/fpu: move FP code to a separate translation unit 2024-05-19 14:36:20 -07:00
test_free_pages.c
test_hash.c
test_hexdump.c test_hexdump: avoid string truncation warning 2024-04-25 21:07:07 -07:00
test_hmm_uapi.h
test_hmm.c lib/test_hmm.c: handle src_pfns and dst_pfns allocation failure 2024-04-25 20:55:48 -07:00
test_ida.c
test_kmod.c
test_kprobes.c
test_linear_ranges.c
test_list_sort.c
test_lockup.c
test_maple_tree.c
test_memcat_p.c
test_meminit.c
test_min_heap.c
test_module.c
test_objagg.c
test_objpool.c
test_parman.c
test_printf.c
test_ref_tracker.c
test_rhashtable.c lib/test_rhashtable: add missing MODULE_DESCRIPTION() macro 2024-06-03 18:51:18 -07:00
test_scanf.c
test_sort.c
test_static_key_base.c
test_static_keys.c
test_sysctl.c
test_ubsan.c ubsan: fix unused variable warning in test module 2024-04-03 14:35:57 -07:00
test_user_copy.c
test_uuid.c
test_vmalloc.c
test_xarray.c The usual shower of singleton fixes and minor series all over MM, 2024-05-19 09:21:03 -07:00
test-kstrtox.c
textsearch.c
timerqueue.c
trace_readwrite.c
ts_bm.c
ts_fsm.c
ts_kmp.c
ubsan.c ubsan: Add awareness of signed integer overflow traps 2024-04-15 17:42:43 -07:00
ubsan.h ubsan: Avoid i386 UBSAN handler crashes with Clang 2024-04-24 15:45:38 -07:00
ucmpdi2.c
ucs2_string.c
usercopy.c usercopy: Don't use "proxy" headers 2024-05-19 16:12:38 -07:00
uuid.c
vsprintf.c wrapper for access to ->bd_partno 2024-05-02 17:48:09 -04:00
win_minmax.c
xarray.c The usual shower of singleton fixes and minor series all over MM, 2024-05-19 09:21:03 -07:00
xxhash.c