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Date: Thu, 15 Jan 2015 20:38:39 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Christian Borntraeger <borntraeger@de.ibm.com>
Subject: Re: [PATCH 4/8] x86/spinlock: Leftover conversion
 ACCESS_ONCE->READ_ONCE
Message-ID: <20150115193839.GA28727@redhat.com>
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 <1421312314-72330-5-git-send-email-borntraeger@de.ibm.com>
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On 01/15, Christian Borntraeger wrote:
>
> --- a/arch/x86/include/asm/spinlock.h
> +++ b/arch/x86/include/asm/spinlock.h
> @@ -186,7 +186,7 @@ static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
>  	__ticket_t head = ACCESS_ONCE(lock->tickets.head);
>  
>  	for (;;) {
> -		struct __raw_tickets tmp = ACCESS_ONCE(lock->tickets);
> +		struct __raw_tickets tmp = READ_ONCE(lock->tickets);

Agreed, but what about another ACCESS_ONCE() above?

Oleg.