 3018965139
			
		
	
	
	3018965139
	
	
	
		
			
			The operations on the bitmap pointers are protected by "memory"
clobbering raw_local_irq_{save,restore}(), so there is no need for
volatile here.  By removing the volatile we get better code generation
out of the compiler.
Signed-off-by: David Daney <david.daney@cavium.com>
Patchwork: http://patchwork.linux-mips.org/patch/4966/
Acked-by: John Crispin <blogic@openwrt.org>
		
	
			
		
			
				
	
	
		
			179 lines
		
	
	
	
		
			4.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			179 lines
		
	
	
	
		
			4.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file "COPYING" in the main directory of this archive
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|  * for more details.
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|  *
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|  * Copyright (c) 1994-1997, 99, 2000, 06, 07 Ralf Baechle (ralf@linux-mips.org)
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|  * Copyright (c) 1999, 2000  Silicon Graphics, Inc.
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|  */
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| #include <linux/bitops.h>
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| #include <linux/irqflags.h>
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| #include <linux/export.h>
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| 
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| 
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| /**
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|  * __mips_set_bit - Atomically set a bit in memory.  This is called by
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|  * set_bit() if it cannot find a faster solution.
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|  * @nr: the bit to set
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|  * @addr: the address to start counting from
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|  */
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| void __mips_set_bit(unsigned long nr, volatile unsigned long *addr)
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| {
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| 	unsigned long *a = (unsigned long *)addr;
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| 	unsigned bit = nr & SZLONG_MASK;
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| 	unsigned long mask;
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| 	unsigned long flags;
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| 
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| 	a += nr >> SZLONG_LOG;
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| 	mask = 1UL << bit;
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| 	raw_local_irq_save(flags);
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| 	*a |= mask;
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| 	raw_local_irq_restore(flags);
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| }
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| EXPORT_SYMBOL(__mips_set_bit);
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| 
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| 
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| /**
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|  * __mips_clear_bit - Clears a bit in memory.  This is called by clear_bit() if
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|  * it cannot find a faster solution.
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|  * @nr: Bit to clear
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|  * @addr: Address to start counting from
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|  */
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| void __mips_clear_bit(unsigned long nr, volatile unsigned long *addr)
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| {
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| 	unsigned long *a = (unsigned long *)addr;
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| 	unsigned bit = nr & SZLONG_MASK;
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| 	unsigned long mask;
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| 	unsigned long flags;
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| 
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| 	a += nr >> SZLONG_LOG;
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| 	mask = 1UL << bit;
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| 	raw_local_irq_save(flags);
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| 	*a &= ~mask;
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| 	raw_local_irq_restore(flags);
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| }
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| EXPORT_SYMBOL(__mips_clear_bit);
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| 
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| 
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| /**
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|  * __mips_change_bit - Toggle a bit in memory.	This is called by change_bit()
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|  * if it cannot find a faster solution.
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|  * @nr: Bit to change
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|  * @addr: Address to start counting from
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|  */
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| void __mips_change_bit(unsigned long nr, volatile unsigned long *addr)
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| {
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| 	unsigned long *a = (unsigned long *)addr;
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| 	unsigned bit = nr & SZLONG_MASK;
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| 	unsigned long mask;
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| 	unsigned long flags;
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| 
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| 	a += nr >> SZLONG_LOG;
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| 	mask = 1UL << bit;
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| 	raw_local_irq_save(flags);
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| 	*a ^= mask;
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| 	raw_local_irq_restore(flags);
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| }
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| EXPORT_SYMBOL(__mips_change_bit);
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| 
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| 
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| /**
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|  * __mips_test_and_set_bit - Set a bit and return its old value.  This is
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|  * called by test_and_set_bit() if it cannot find a faster solution.
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|  * @nr: Bit to set
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|  * @addr: Address to count from
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|  */
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| int __mips_test_and_set_bit(unsigned long nr,
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| 			    volatile unsigned long *addr)
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| {
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| 	unsigned long *a = (unsigned long *)addr;
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| 	unsigned bit = nr & SZLONG_MASK;
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| 	unsigned long mask;
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| 	unsigned long flags;
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| 	int res;
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| 
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| 	a += nr >> SZLONG_LOG;
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| 	mask = 1UL << bit;
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| 	raw_local_irq_save(flags);
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| 	res = (mask & *a) != 0;
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| 	*a |= mask;
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| 	raw_local_irq_restore(flags);
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| 	return res;
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| }
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| EXPORT_SYMBOL(__mips_test_and_set_bit);
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| 
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| 
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| /**
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|  * __mips_test_and_set_bit_lock - Set a bit and return its old value.  This is
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|  * called by test_and_set_bit_lock() if it cannot find a faster solution.
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|  * @nr: Bit to set
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|  * @addr: Address to count from
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|  */
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| int __mips_test_and_set_bit_lock(unsigned long nr,
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| 				 volatile unsigned long *addr)
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| {
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| 	unsigned long *a = (unsigned long *)addr;
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| 	unsigned bit = nr & SZLONG_MASK;
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| 	unsigned long mask;
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| 	unsigned long flags;
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| 	int res;
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| 
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| 	a += nr >> SZLONG_LOG;
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| 	mask = 1UL << bit;
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| 	raw_local_irq_save(flags);
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| 	res = (mask & *a) != 0;
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| 	*a |= mask;
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| 	raw_local_irq_restore(flags);
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| 	return res;
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| }
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| EXPORT_SYMBOL(__mips_test_and_set_bit_lock);
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| 
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| 
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| /**
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|  * __mips_test_and_clear_bit - Clear a bit and return its old value.  This is
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|  * called by test_and_clear_bit() if it cannot find a faster solution.
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|  * @nr: Bit to clear
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|  * @addr: Address to count from
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|  */
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| int __mips_test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
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| {
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| 	unsigned long *a = (unsigned long *)addr;
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| 	unsigned bit = nr & SZLONG_MASK;
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| 	unsigned long mask;
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| 	unsigned long flags;
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| 	int res;
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| 
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| 	a += nr >> SZLONG_LOG;
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| 	mask = 1UL << bit;
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| 	raw_local_irq_save(flags);
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| 	res = (mask & *a) != 0;
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| 	*a &= ~mask;
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| 	raw_local_irq_restore(flags);
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| 	return res;
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| }
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| EXPORT_SYMBOL(__mips_test_and_clear_bit);
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| 
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| 
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| /**
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|  * __mips_test_and_change_bit - Change a bit and return its old value.	This is
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|  * called by test_and_change_bit() if it cannot find a faster solution.
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|  * @nr: Bit to change
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|  * @addr: Address to count from
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|  */
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| int __mips_test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
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| {
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| 	unsigned long *a = (unsigned long *)addr;
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| 	unsigned bit = nr & SZLONG_MASK;
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| 	unsigned long mask;
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| 	unsigned long flags;
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| 	int res;
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| 
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| 	a += nr >> SZLONG_LOG;
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| 	mask = 1UL << bit;
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| 	raw_local_irq_save(flags);
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| 	res = (mask & *a) != 0;
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| 	*a ^= mask;
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| 	raw_local_irq_restore(flags);
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| 	return res;
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| }
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| EXPORT_SYMBOL(__mips_test_and_change_bit);
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