From mboxrd@z Thu Jan 1 00:00:00 1970 From: peterz@infradead.org (Peter Zijlstra) Date: Tue, 17 Nov 2015 12:07:49 +0100 Subject: local64_cmpxchg() in arc_perf_event_update() In-Reply-To: References: <1445286926.3913.13.camel@synopsys.com> List-ID: Message-ID: <20151117110749.GT3816@twins.programming.kicks-ass.net> To: linux-snps-arc@lists.infradead.org On Tue, Nov 17, 2015@09:14:59AM +0000, Vineet Gupta wrote: > Let's check with Peter as I'm not sure how exactly the read call will > nest for same counter on same core ? Various possible ways, but the easiest is userspace doing a sys_read() on the counter while the NMI happens.