| From | Song Liu <> | Date | Tue, 21 Jul 2020 23:40:16 -0700 | Subject | Re: [PATCH v4 19/24] raid5: Use sequence counter with associated spinlock |
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On Mon, Jul 20, 2020 at 8:57 AM Ahmed S. Darwish <a.darwish@linutronix.de> wrote: > > A sequence counter write side critical section must be protected by some > form of locking to serialize writers. A plain seqcount_t does not > contain the information of which lock must be held when entering a write > side critical section. > > Use the new seqcount_spinlock_t data type, which allows to associate a > spinlock with the sequence counter. This enables lockdep to verify that > the spinlock used for writer serialization is held when the write side > critical section is entered. > > If lockdep is disabled this lock association is compiled out and has > neither storage size nor runtime overhead. > > Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Acked-by: Song Liu <song@kernel.org>
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