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From: Oliver Neukum <oliver@neukum.org>
To: "jidong xiao" <jidong.xiao@gmail.com>
Subject: Re: [linux-kernel]Why there are so many struct rw_semaphore being defined?
Date: Wed, 4 Jul 2007 11:15:06 +0200
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Am Mittwoch, 4. Juli 2007 schrieb jidong xiao:
> I see struct rw_semaphore is defined in
> include/linux/rwsem-spinlock.h,in the meanwhile, I also can find it in

Quote:

#ifndef _LINUX_RWSEM_H
#error "please don't include linux/rwsem-spinlock.h directly, use linux/rwsem.h instead"
#endif

> include/asm-**/rwsem.h,for
> example,include/asm-i386/rwsem.h,include/asm-x86_64/rwsem.h,why?which
> one should be used?

This structure is so important to performance that some architectures
have version optimized to their features.

	Regards
		Oliver