Re: [PATCHSET 9/9] add hotplug support

[Jeff Garzik <jgarzik@pobox.com>]

Tejun Heo wrote:
> zhao, forrest wrote:
>> On Tue, 2006-04-11 at 23:14 +0900, Tejun Heo wrote:
>>
>>> Warm unplug/plug comes at almost no cost for LLDDs implementing new EH
>>> - adding a call to ata_eh_hotplug() at the end of ->error_handler is
>>> enough (even this is unnecessary if it's using bmdma error_handler).
>>> e.g. ata_piix isn't changed by hotplug patchsets at all but still
>>> supports warm plugging (even PATA warm plugging works although it's
>>> electronically unsafe).
>>>
>>> To support full hot unplug/plug, all a LLDD has to do are enabling PHY
>>> status changed interrupt and, when PHY RDY status changes, call
>>> ata_schedule_probe() and schedule EH.  ahci, sata_sil and sata_sil24
>>> are converted this way and hotplugging works perfectly for those
>>> drivers.
>>>
>> In order to make ata_eh_hotplug() called, LLDD have to schedule EH
>> in its interrupt handler(i.e. invoke scsi_eh_schedule_host() directly
>> or indirectly), but I didn't find such code in your patch set.
>> Did I miss anything?
>>
> 
> The last three patches do that.  All hotplug interrupts end up invoking
> EH by calling ata_eh_schedule_port(ap, ATA_EH_FREEZE).

It's certainly nicer and more readable, if the LLDD calls a function
like ata_eh_hotplug().

	Jeff