From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: Race between vmtruncate and mapped areas? From: Daniel McNeil In-Reply-To: <20030515231714.GL1429@dualathlon.random> References: <20030514103421.197f177a.akpm@digeo.com> <82240000.1052934152@baldur.austin.ibm.com> <20030515004915.GR1429@dualathlon.random> <20030515013245.58bcaf8f.akpm@digeo.com> <20030515085519.GV1429@dualathlon.random> <20030515022000.0eb9db29.akpm@digeo.com> <20030515094041.GA1429@dualathlon.random> <1053016706.2693.10.camel@ibm-c.pdx.osdl.net> <20030515191921.GJ1429@dualathlon.random> <1053036250.2696.33.camel@ibm-c.pdx.osdl.net> <20030515231714.GL1429@dualathlon.random> Content-Type: text/plain Message-Id: <1053131245.2690.78.camel@ibm-c.pdx.osdl.net> Mime-Version: 1.0 Date: 16 May 2003 17:27:25 -0700 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andrea Arcangeli Cc: Andrew Morton , dmccr@us.ibm.com, mika.penttila@kolumbus.fi, linux-mm@kvack.org, Linux Kernel Mailing List List-ID: On Thu, 2003-05-15 at 16:17, Andrea Arcangeli wrote: > no, the spin_lock only acts as a barrier in one way, not both ways, so > an smp_something is still needed. > Can you explain this more? On a x86, isn't a spin_lock a lock; dec instruction and the rmb() a lock; addl. I thought x86 instructions with lock prefix provided a memory barrier. Just curious, -- Daniel McNeil -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: aart@kvack.org