From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mosberger Date: Mon, 07 Apr 2003 22:58:13 +0000 Subject: Re: [Linux-ia64] spin_unlock() problem Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org >>>>> On 07 Apr 2003 18:09:44 -0400, Jes Sorensen said: Jes> Quoting section 4.4.7 "Memory Access Ordering", 2nd paragraph, Jes> it says " .... Release data accesses guarantee that all Jes> previous data accesses are made visible prior to being made Jes> visible themselves." Oops, sorry, I got it exactly backwards. ;-( So much for giving a "quick" reply... Jes> The way I understand that, it is possible that a store Jes> performed after an st.rel may become visible prior to the Jes> st.rel, like in this example: Jes> st [r2] = r32 (1) Jes> st.rel [r3] = r33 (2) Jes> st [r4] = r34 (3) Jes> In other words we are only guarantied that [r2] is valid when Jes> [r3] appears but have no guarantie that [r4] doesn't show up on Jes> the bus prior to [r3]? I wouldn't use the word "valid" here, but yes, (2) and (3) are NOT ordered. --david