Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753472AbbKQMZp (ORCPT ); Tue, 17 Nov 2015 07:25:45 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:47300 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751636AbbKQMZo (ORCPT ); Tue, 17 Nov 2015 07:25:44 -0500 Date: Tue, 17 Nov 2015 13:25:40 +0100 From: Peter Zijlstra To: Vineet Gupta Cc: Alexey Brodkin , arcml , lkml Subject: Re: local64_cmpxchg() in arc_perf_event_update() Message-ID: <20151117122540.GL11639@twins.programming.kicks-ass.net> References: <1445286926.3913.13.camel@synopsys.com> <20151117110749.GT3816@twins.programming.kicks-ass.net> <564B0E18.3040207@synopsys.com> <20151117122401.GY3816@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151117122401.GY3816@twins.programming.kicks-ass.net> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 619 Lines: 14 On Tue, Nov 17, 2015 at 01:24:01PM +0100, Peter Zijlstra wrote: > On Tue, Nov 17, 2015 at 04:53:04PM +0530, Vineet Gupta wrote: > > That means Alexey need to revert the hunk ? > > Yes, I think so. This is assuming you now have these NMIs we talked about earlier. If all you have are regular IRQs this is not possible, for we should be calling ->read() with IRQs disabled. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/