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39c715b717
This patch implements a number of smp_processor_id() cleanup ideas that
Arjan van de Ven and I came up with.
The previous __smp_processor_id/_smp_processor_id/smp_processor_id API
spaghetti was hard to follow both on the implementational and on the
usage side.
Some of the complexity arose from picking wrong names, some of the
complexity comes from the fact that not all architectures defined
__smp_processor_id.
In the new code, there are two externally visible symbols:
- smp_processor_id(): debug variant.
- raw_smp_processor_id(): nondebug variant. Replaces all existing
uses of _smp_processor_id() and __smp_processor_id(). Defined
by every SMP architecture in include/asm-*/smp.h.
There is one new internal symbol, dependent on DEBUG_PREEMPT:
- debug_smp_processor_id(): internal debug variant, mapped to
smp_processor_id().
Also, i moved debug_smp_processor_id() from lib/kernel_lock.c into a new
lib/smp_processor_id.c file. All related comments got updated and/or
clarified.
I have build/boot tested the following 8 .config combinations on x86:
{SMP,UP} x {PREEMPT,!PREEMPT} x {DEBUG_PREEMPT,!DEBUG_PREEMPT}
I have also build/boot tested x64 on UP/PREEMPT/DEBUG_PREEMPT. (Other
architectures are untested, but should work just fine.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
50 lines
893 B
C
50 lines
893 B
C
/* delay.c: Delay loops for sparc64
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*
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* Copyright (C) 2004 David S. Miller <davem@redhat.com>
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*
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* Based heavily upon x86 variant which is:
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* Copyright (C) 1993 Linus Torvalds
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* Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
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*/
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#include <linux/delay.h>
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void __delay(unsigned long loops)
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{
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__asm__ __volatile__(
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" b,pt %%xcc, 1f\n"
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" cmp %0, 0\n"
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" .align 32\n"
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"1:\n"
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" bne,pt %%xcc, 1b\n"
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" subcc %0, 1, %0\n"
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: "=&r" (loops)
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: "0" (loops)
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: "cc");
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}
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/* We used to multiply by HZ after shifting down by 32 bits
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* but that runs into problems for higher values of HZ and
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* slow cpus.
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*/
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void __const_udelay(unsigned long n)
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{
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n *= 4;
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n *= (cpu_data(raw_smp_processor_id()).udelay_val * (HZ/4));
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n >>= 32;
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__delay(n + 1);
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}
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void __udelay(unsigned long n)
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{
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__const_udelay(n * 0x10c7UL);
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}
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void __ndelay(unsigned long n)
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{
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__const_udelay(n * 0x5UL);
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}
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