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668b448466
linux/arch/x86
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Sebastian Andrzej Siewior 668b448466 x86/div64: Add a micro-optimization shortcut if base is power of two 
In the target code I have a do_div(x, PAGE_SIZE). The x86-64
version of it was doing a shift and a mask which is clever. The
32bit version of it had a div operation in it which made me
think. After digging I noticed that x86 has an optimized version
of it. This patch adds this shift and mask optimization if base
is constant so we don't have any runtime "checking" overhead
since most users use a power of ten.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1322649814-544-1-git-send-email-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 18:16:11 +01:00
..
boot doc: fix broken references 2011-09-27 18:08:04 +02:00
configs
crypto Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
ia32 x86-64: Cleanup some assembly entry points 2011-12-05 17:24:43 +01:00
include/asm x86/div64: Add a micro-optimization shortcut if base is power of two 2011-12-05 18:16:11 +01:00
kernel x86-64: Cleanup some assembly entry points 2011-12-05 17:24:43 +01:00
kvm KVM: VMX: Check for automatic switch msr table overflow 2011-11-17 16:28:09 +02:00
lguest lguest: add export.h to lguest files for THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:32:13 -04:00
lib x86: Fix insn decoder for longer instruction 2011-10-10 09:05:51 +02:00
math-emu
mm x86-64: Set siginfo and context on vsyscall emulation faults 2011-12-05 12:17:27 +01:00
net
oprofile Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-10-26 17:03:38 +02:00
pci x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:30:35 -04:00
platform x86, efi: Convert efi_phys_get_time() args to physical addresses 2011-12-05 12:45:14 +01:00
power x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:30:35 -04:00
tools
um fix braino in um patchset (mea culpa) 2011-11-21 12:10:21 -08:00
vdso Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-10-28 05:03:12 -07:00
video x86: fix up files really needing to include module.h 2011-10-31 19:30:36 -04:00
xen xen/pm_idle: Make pm_idle be default_idle under Xen. 2011-12-03 10:49:58 -08:00
.gitignore
Kbuild
Kconfig Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2011-11-06 18:54:53 -08:00
Kconfig.cpu
Kconfig.debug doc: fix broken references 2011-09-27 18:08:04 +02:00
Makefile
Makefile_32.cpu
Makefile.um um: take arch/um/sys-x86 to arch/x86/um 2011-11-02 14:15:05 +01:00