mirror of https://github.com/torvalds/linux.git
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> |
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| .. | ||
| power | ||
| regmap | ||
| test | ||
| Kconfig | ||
| Makefile | ||
| 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.c | ||
| firmware_class.c | ||
| hypervisor.c | ||
| init.c | ||
| isa.c | ||
| 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 | ||