| Date | Tue, 24 Oct 2017 11:31:04 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH 17/19] locking/barriers: Kill lockless_dereference |
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* Paul E. McKenney <paulmck@linux.vnet.ibm.com> wrote:
> From: Will Deacon <will.deacon@arm.com> > > lockless_dereference is a nice idea, but its gained little traction in > kernel code since it's introduction three years ago. This is partly
s/its/it s/it's/its
> because it's a pain to type, but also because using READ_ONCE instead > will work correctly on all architectures apart from Alpha, which is a > fully supported but somewhat niche architecture these days. > > This patch moves smp_read_barrier_depends() (a NOP on all architectures > other than Alpha) from lockless_dereference into READ_ONCE, converts > the few actual users over to READ_ONCE and then finally removes > lockless_dereference altogether.
Nit: if we refer to smp_read_barrier_depends() with parentheses (which is the nice thing to do for function-alike symbols), then we should do the same with READ_ONCE() and lockless_dereference() as well.
Also, could we please split this into three patches:
#1: Add smp_read_barrier_depends() to READ_ONCE() #2: Convert all lockless_dereference() users to READ_ONCE() #3: Remove the now unused lockless_dereference() API
to make it easier to analyze if bisected to, should any problems arise?
Thanks,
Ingo
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