Re: [PATCH v2] scsi: core: Drop Scsi_Host.default_lock

Damien Le Moal <[email protected]> Thu, 6 Aug 2026 09:30:34 -0700
Newsgroups gmane.linux.ports.ppc.embedded,gmane.linux.scsi,gmane.linux.ide,gmane.linux.kernel,gmane.linux.usb.general
Organization Western Digital Research
Message-ID <[email protected]>
On 2026/08/06 4:39, John Garry wrote:
> From: John Garry <[email protected]>
> 
> Back in the 2.6.xx days, it was possible to for low-level drivers to set

s/to for/for

> the shost lock pointer. That is why there is a default lock and a pointer
> to the shost lock.
> 
> However, support for this has long been removed, so drop
> Scsi_Host.default_lock and make Scsi_Host.host_lock as the actual lock.
> 
> Getting the address of embedded host_lock structure just requires adding
> a fixed offset value to the shost pointer. However, getting the value of
> the host_lock pointer requires loading from a fixed offset to the shost
> pointer. The latter should be very slightly slower, which is relevant as
> this lock is used a lot throughout the core code and drivers.
> 
> Signed-off-by: John Garry <[email protected]>
For the ata bits,

Acked-by: Damien Le Moal <[email protected]>

-- 
Damien Le Moal
Western Digital Research