Re: Full hostlock pushdown available

Andi Kleen
2010-11-02T09:21:11Z

> It's a bit disappointing that libata's lock profile in this patch is
> quite different than that of current upstream: with your patch,
> libata holds the scsi host lock for a considerably longer period of
> time, while also holding the ATA port/host spinlock.

The goal here is not really what comes out of this patch,
but dropping the host lock completely. This is just the first step.

>
> IOW, it's doing the exact opposite of what the previous code did
> (release the scsi host lock, before acquiring the ATA port/host
> spinlock), not at all an equivalent transformation.
>
> The following sequence would seem to better preserve the existing
> lock profile, correct?

Possibly, but it's not a mechanic change.

-Andi