forked from luck/tmp_suning_uos_patched
64970b68d2
This moves an optimization for searching constant-sized small bitmaps form x86_64-specific to generic code. On an i386 defconfig (the x86#testing one), the size of vmlinux hardly changes with this applied. I have observed only four places where this optimization avoids a call into find_next_bit: In the functions return_unused_surplus_pages, alloc_fresh_huge_page, and adjust_pool_surplus, this patch avoids a call for a 1-bit bitmap. In __next_cpu a call is avoided for a 32-bit bitmap. That's it. On x86_64, 52 locations are optimized with a minimal increase in code size: Current #testing defconfig: 146 x bsf, 27 x find_next_*bit text data bss dec hex filename 5392637 846592 724424 6963653 6a41c5 vmlinux After removing the x86_64 specific optimization for find_next_*bit: 94 x bsf, 79 x find_next_*bit text data bss dec hex filename 5392358 846592 724424 6963374 6a40ae vmlinux After this patch (making the optimization generic): 146 x bsf, 27 x find_next_*bit text data bss dec hex filename 5392396 846592 724424 6963412 6a40d4 vmlinux [ tglx@linutronix.de: build fixes ] Signed-off-by: Ingo Molnar <mingo@elte.hu> |
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.. | ||
bitops | ||
4level-fixup.h | ||
atomic.h | ||
audit_change_attr.h | ||
audit_dir_write.h | ||
audit_read.h | ||
audit_signal.h | ||
audit_write.h | ||
bitops.h | ||
bug.h | ||
cmpxchg-local.h | ||
cmpxchg.h | ||
cputime.h | ||
device.h | ||
div64.h | ||
dma-mapping-broken.h | ||
dma-mapping.h | ||
emergency-restart.h | ||
errno-base.h | ||
errno.h | ||
fcntl.h | ||
futex.h | ||
gpio.h | ||
ide_iops.h | ||
ioctl.h | ||
iomap.h | ||
irq_regs.h | ||
Kbuild | ||
Kbuild.asm | ||
kdebug.h | ||
libata-portmap.h | ||
local.h | ||
memory_model.h | ||
mm_hooks.h | ||
mman.h | ||
mutex-dec.h | ||
mutex-null.h | ||
mutex-xchg.h | ||
page.h | ||
pci-dma-compat.h | ||
pci.h | ||
percpu.h | ||
pgtable-nopmd.h | ||
pgtable-nopud.h | ||
pgtable.h | ||
poll.h | ||
resource.h | ||
rtc.h | ||
sections.h | ||
siginfo.h | ||
signal.h | ||
statfs.h | ||
termios.h | ||
tlb.h | ||
topology.h | ||
uaccess.h | ||
unaligned.h | ||
vmlinux.lds.h | ||
xor.h |