On Tue, Feb 18, 2020 at 03:39:17PM +0100, Merlijn Wajer wrote:
> When replacing the Big Kernel Lock in commit
> 2a48fc0ab24241755dc93bfd4f01d68efab47f5a ("block: autoconvert trivial
> BKL users to private mutex"), the lock was replaced with a sr-wide lock.
>
> This causes very poor performance when using multiple sr devices, as the
> sr driver was not able to execute more than one command to one drive at
> any given time, even when there were many CD drives available.
>
> Replace the global mutex with per-sr-device mutex.
Do we actually need the lock at all? What is protected by it?
