2011-07-19 19:59:51 +08:00
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/* Slow paths of read/write spinlocks. */
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#include <linux/linkage.h>
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#include <asm/alternative-asm.h>
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#include <asm/frame.h>
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#include <asm/rwlock.h>
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#ifdef CONFIG_X86_32
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# define __lock_ptr eax
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#else
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# define __lock_ptr rdi
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#endif
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ENTRY(__write_lock_failed)
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CFI_STARTPROC
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FRAME
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0: LOCK_PREFIX
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2011-07-19 20:00:45 +08:00
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WRITE_LOCK_ADD($RW_LOCK_BIAS) (%__lock_ptr)
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2011-07-19 19:59:51 +08:00
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1: rep; nop
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2011-07-19 20:00:45 +08:00
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cmpl $WRITE_LOCK_CMP, (%__lock_ptr)
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2011-07-19 19:59:51 +08:00
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jne 1b
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LOCK_PREFIX
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2011-07-19 20:00:45 +08:00
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WRITE_LOCK_SUB($RW_LOCK_BIAS) (%__lock_ptr)
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2011-07-19 19:59:51 +08:00
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jnz 0b
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ENDFRAME
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ret
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CFI_ENDPROC
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END(__write_lock_failed)
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ENTRY(__read_lock_failed)
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CFI_STARTPROC
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FRAME
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0: LOCK_PREFIX
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2011-07-19 20:00:45 +08:00
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READ_LOCK_SIZE(inc) (%__lock_ptr)
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2011-07-19 19:59:51 +08:00
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1: rep; nop
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2011-07-19 20:00:45 +08:00
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READ_LOCK_SIZE(cmp) $1, (%__lock_ptr)
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2011-07-19 19:59:51 +08:00
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js 1b
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LOCK_PREFIX
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2011-07-19 20:00:45 +08:00
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READ_LOCK_SIZE(dec) (%__lock_ptr)
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2011-07-19 19:59:51 +08:00
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js 0b
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ENDFRAME
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ret
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CFI_ENDPROC
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END(__read_lock_failed)
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