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https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
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10fa1155a2
Currently we have a confused udelay implementation. * __const_udelay does not accept usecs but xloops in i386 and x86_64 * our implementation requires usecs as arg * it gets a xloops count when called by asm/arch/delay.h Bugs related to this (extremely long shutdown times) where reported by some x86_64 users, especially using Device Mapper. To hit this bug, a compile-time constant time parameter must be passed - that's why UML seems to work most times. Fix this with a simple udelay implementation. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Acked-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
31 lines
510 B
C
31 lines
510 B
C
/*
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* Copyright 2003 PathScale, Inc.
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* Copied from arch/x86_64
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*
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* Licensed under the GPL
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*/
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#include <linux/module.h>
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#include <linux/delay.h>
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#include <asm/processor.h>
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#include <asm/param.h>
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void __delay(unsigned long loops)
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{
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unsigned long i;
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for(i = 0; i < loops; i++)
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cpu_relax();
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}
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void __udelay(unsigned long usecs)
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{
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unsigned long i, n;
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n = (loops_per_jiffy * HZ * usecs) / MILLION;
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for(i=0;i<n;i++)
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cpu_relax();
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}
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EXPORT_SYMBOL(__udelay);
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