kernel_samsung_sm7125

jenna

History

David Howells 690d137f44 Reduce the number of expensive division instructions done by _parse_integer() _parse_integer() does one or two division instructions (which are slow) per digit parsed to perform the overflow check. Furthermore, these are particularly expensive examples of division instruction as the number of clock cycles required to complete them may go up with the position of the most significant set bit in the dividend: if (*res > div_u64(ULLONG_MAX - val, base)) which is as maximal as possible. Worse, on 32-bit arches, more than one of these division instructions may be required per digit. So, assuming we don't support a base of more than 16, skip the check if the top nibble of the result is not set at this point. Signed-off-by: David Howells <dhowells@redhat.com> [ Changed it to not dereference the pointer all the time - even if the compiler can and does optimize it away, the code just looks cleaner. And edited the top nybble test slightly to make the code generated on x86-64 better in the loop - test against a hoisted constant instead of shifting and testing the result ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		13 years ago
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lzo	…
mpi	lib: Fix 32-bit sparc udiv_qrnnd() definition in mpilib's longlong.h	13 years ago
raid6	md: Add in export.h for files using EXPORT_SYMBOL	13 years ago
reed_solomon	…
xz	…
zlib_deflate	…
zlib_inflate	…
.gitignore	…
Kconfig	arch: fix ioport mapping on mips,sh	13 years ago
Kconfig.debug	kmemleak: Add support for memory hotplug	13 years ago
Kconfig.kgdb	…
Kconfig.kmemcheck	…
Makefile	lib: Fix multiple definitions of clz_tab	13 years ago
argv_split.c	…
atomic64.c	…
atomic64_test.c	…
audit.c	…
average.c	…
bcd.c	…
bch.c	…
bitmap.c	lib/bitmap.c: quiet sparse noise about address space	13 years ago
bitrev.c	…
bsearch.c	…
btree.c	btree: export btree_get_prev() so modules can use btree_for_each	13 years ago
bug.c	bugs, x86: Fix printk levels for panic, softlockups and stack dumps	13 years ago
bust_spinlocks.c	…
check_signature.c	…
checksum.c	…
clz_tab.c	lib: Fix multiple definitions of clz_tab	13 years ago
cmdline.c	…
cordic.c	Docs: wording: functions -> algorithm	13 years ago
cpu-notifier-error-inject.c	…
cpu_rmap.c	…
cpumask.c	…
crc-ccitt.c	…
crc-itu-t.c	…
crc-t10dif.c	…
crc7.c	…
crc8.c	…
crc16.c	…
crc32.c	crc32: optimize inner loop	13 years ago
crc32defs.h	…
ctype.c	…
debug_locks.c	…
debugobjects.c	debugobjects: Extend to assert that an object is initialized	13 years ago
dec_and_lock.c	…
decompress.c	…
decompress_bunzip2.c	decompress_bunzip2: remove invalid vi modeline	13 years ago
decompress_inflate.c	…
decompress_unlzma.c	treewide: Fix comment and string typo 'bufer'	13 years ago
decompress_unlzo.c	unlzo: fix input buffer free	13 years ago
decompress_unxz.c	…
devres.c	Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci	13 years ago
digsig.c	lib/digsig: checks for NULL return value	13 years ago
div64.c	…
dma-debug.c	Fix comparison using wrong pointer variable in dma debug code	13 years ago
dump_stack.c	…
dynamic_debug.c	Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core	13 years ago
dynamic_queue_limits.c	dql: Dynamic queue limits	13 years ago
extable.c	…
fault-inject.c	switch debugfs to umode_t	13 years ago
find_last_bit.c	…
find_next_bit.c	…
flex_array.c	…
gcd.c	…
gen_crc32table.c	…
genalloc.c	…
halfmd4.c	…
hexdump.c	…
hweight.c	…
idr.c	ida: make ida_simple_get/put() IRQ safe	13 years ago
inflate.c	…
int_sqrt.c	…
iomap.c	lib: add GENERIC_PCI_IOMAP	13 years ago
iomap_copy.c	…
iommu-helper.c	…
ioremap.c	…
irq_regs.c	…
is_single_threaded.c	…
kasprintf.c	…
klist.c	…
kobject.c	kobject: remove kset_find_obj_hinted()	13 years ago
kobject_uevent.c	driver-core: skip uevent generation when nobody is listening	13 years ago
kstrtox.c	Reduce the number of expensive division instructions done by _parse_integer()	13 years ago
kstrtox.h	lib/kstrtox: common code between kstrto() and simple_strto() functions	13 years ago
lcm.c	…
libcrc32c.c	…
list_debug.c	…
list_sort.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-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	…
lru_cache.c	…
md5.c	…
nlattr.c	netlink: validate NLA_MSECS length	13 years ago
parser.c	…
pci_iomap.c	lib: add NO_GENERIC_PCI_IOPORT_MAP	13 years ago
percpu_counter.c	lib/percpu_counter.c: enclose hotplug only variables in hotplug ifdef	13 years ago
plist.c	…
prio_heap.c	…
prio_tree.c	…
proportions.c	…
radix-tree.c	radix_tree: take radix_tree_path off stack	13 years ago
random32.c	…
ratelimit.c	…
rational.c	…
rbtree.c	…
reciprocal_div.c	sch_red: Adaptative RED AQM	13 years ago
rwsem-spinlock.c	…
rwsem.c	…
scatterlist.c	…
sha1.c	…
show_mem.c	…
smp_processor_id.c	…
sort.c	…
spinlock_debug.c	lib/spinlock_debug.c: print owner on spinlock lockup	13 years ago
string.c	lib/string.c: fix strim() semantics for strings that have only blanks	13 years ago
string_helpers.c	…
swiotlb.c	swiotlb: Expose swiotlb_nr_tlb function to modules	13 years ago
syscall.c	…
test-kstrtox.c	…
textsearch.c	…
timerqueue.c	…
ts_bm.c	…
ts_fsm.c	…
ts_kmp.c	…
uuid.c	…
vsprintf.c	net: introduce and use netdev_features_t for device features sets	13 years ago