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Date:   Fri, 31 May 2019 13:24:07 +0200
From:   Roman Penyaev <rpenyaev@suse.de>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     azat@libevent.org, akpm@linux-foundation.org,
        viro@zeniv.linux.org.uk, torvalds@linux-foundation.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 06/13] epoll: introduce helpers for adding/removing
 events to uring
In-Reply-To: <20190531095549.GB17637@hirez.programming.kicks-ass.net>
References: <20190516085810.31077-1-rpenyaev@suse.de>
 <20190516085810.31077-7-rpenyaev@suse.de>
 <20190531095549.GB17637@hirez.programming.kicks-ass.net>
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On 2019-05-31 11:55, Peter Zijlstra wrote:
> On Thu, May 16, 2019 at 10:58:03AM +0200, Roman Penyaev wrote:
>> +#define atomic_set_unless_zero(ptr, flags)			\
>> +({								\
>> +	typeof(ptr) _ptr = (ptr);				\
>> +	typeof(flags) _flags = (flags);				\
>> +	typeof(*_ptr) _old, _val = READ_ONCE(*_ptr);		\
>> +								\
>> +	for (;;) {						\
>> +		if (!_val)					\
>> +			break;					\
>> +		_old = cmpxchg(_ptr, _val, _flags);		\
>> +		if (_old == _val)				\
>> +			break;					\
>> +		_val = _old;					\
>> +	}							\
>> +	_val;							\
>> +})
> 
>> +#define atomic_or_with_mask(ptr, flags, mask)			\
>> +({								\
>> +	typeof(ptr) _ptr = (ptr);				\
>> +	typeof(flags) _flags = (flags);				\
>> +	typeof(flags) _mask = (mask);				\
>> +	typeof(*_ptr) _old, _new, _val = READ_ONCE(*_ptr);	\
>> +								\
>> +	for (;;) {						\
>> +		_new = (_val & ~_mask) | _flags;		\
>> +		_old = cmpxchg(_ptr, _val, _new);		\
>> +		if (_old == _val)				\
>> +			break;					\
>> +		_val = _old;					\
>> +	}							\
>> +	_val;							\
>> +})
> 
> Don't call them atomic_*() if they're not part of the atomic_t
> interface.

Can we add those two?  Or keep it local is better?

--
Roman