From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vineet Gupta <vgupta@synopsys.com>
Subject: Re: [PATCH] coredump: Replace opencoded set_mask_bits()
Date: Fri, 07 Aug 2015 21:05:06 +0530
Message-ID: <55C4D02A.5000902@synopsys.com>
References: <1438935406-5762-1-git-send-email-vgupta@synopsys.com> <20150807115710.GA16897@redhat.com> <55C4C433.5000501@synopsys.com> <20150807145737.GL16853@twins.programming.kicks-ass.net>
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Cc: Oleg Nesterov <oleg@redhat.com>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
To: Peter Zijlstra <peterz@infradead.org>
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On Friday 07 August 2015 08:27 PM, Peter Zijlstra wrote:
> On Fri, Aug 07, 2015 at 08:14:03PM +0530, Vineet Gupta wrote:
> 
>> > See, I have such a cmpxchg loop in ARC code - originally from Peter :-)
>> > arch/arc/kernel/smp.c. @ipi_data_ptr is NOT atomic_t
>> > 
>> > 	do {
>> > 		new = old = ACCESS_ONCE(*ipi_data_ptr);
>> > 		new |= 1U << msg;
>> > 	} while (cmpxchg(ipi_data_ptr, old, new) != old);
>> > 
> Well, you'll have atomic_or() real soon now.


Doesn't help my cause - ipi_data_ptr is not atomic_t - hence my prev question in
this thread