Re: [PATCH v3 1/1] loop: scale loop device by introducing per device lock

From: Petr Vorel
Date: Tue Jan 26 2021 - 13:06:20 EST


Hi,

> Currently, loop device has only one global lock:
> loop_ctl_mutex.

> This becomes hot in scenarios where many loop devices are used.

> Scale it by introducing per-device lock: lo_mutex that protects the
> fields in struct loop_device. Keep loop_ctl_mutex to protect global
> data such as loop_index_idr, loop_lookup, loop_add.

> Lock ordering: loop_ctl_mutex > lo_mutex.

Reviewed-by: Petr Vorel <pvorel@xxxxxxx>

Kind regards,
Petr