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SubjectRe: [PATCH AUTOSEL 4.19 14/14] fs/dcache: Disable preemption on i_dir_seq write side on PREEMPT_RT
Hi!

> From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
>
> [ Upstream commit cf634d540a29018e8d69ab1befb7e08182bc6594 ]
>
> i_dir_seq is a sequence counter with a lock which is represented by the
> lowest bit. The writer atomically updates the counter which ensures that it
> can be modified by only one writer at a time. This requires preemption to
> be disabled across the write side critical section.
>
> On !PREEMPT_RT kernels this is implicit by the caller acquiring
> dentry::lock. On PREEMPT_RT kernels spin_lock() does not disable preemption

This should not be applied to 4.19 as CONFIG_PREEMPT_RT does not exist
there.

Best regards,
Pavel
--
'DENX Software Engineering GmbH, Managing Director: Wolfgang Denk'
'HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany'

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