9b130ad5bb
First, number of CPUs can't be negative number. Second, different signnnedness leads to suboptimal code in the following cases: 1) kmalloc(nr_cpu_ids * sizeof(X)); "int" has to be sign extended to size_t. 2) while (loff_t *pos < nr_cpu_ids) MOVSXD is 1 byte longed than the same MOV. Other cases exist as well. Basically compiler is told that nr_cpu_ids can't be negative which can't be deduced if it is "int". Code savings on allyesconfig kernel: -3KB add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370) function old new delta coretemp_cpu_online 450 512 +62 rcu_init_one 1234 1272 +38 pci_device_probe 374 399 +25 ... pgdat_reclaimable_pages 628 556 -72 select_fallback_rq 446 369 -77 task_numa_find_cpu 1923 1807 -116 Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
---|---|---|
.. | ||
power | ||
regmap | ||
test | ||
arch_topology.c | ||
attribute_container.c | ||
base.h | ||
bus.c | ||
cacheinfo.c | ||
class.c | ||
component.c | ||
container.c | ||
core.c | ||
cpu.c | ||
dd.c | ||
devcoredump.c | ||
devres.c | ||
devtmpfs.c | ||
dma-coherent.c | ||
dma-contiguous.c | ||
dma-mapping.c | ||
driver.c | ||
firmware_class.c | ||
firmware.c | ||
hypervisor.c | ||
init.c | ||
isa.c | ||
Kconfig | ||
Makefile | ||
map.c | ||
memory.c | ||
module.c | ||
node.c | ||
pinctrl.c | ||
platform-msi.c | ||
platform.c | ||
property.c | ||
soc.c | ||
syscore.c | ||
topology.c | ||
transport_class.c |