Re: [PATCH] ata: libata-eh: avoid unnecessary calls to ata_scsi_port_error_handler()

[Damien Le Moal <dlemoal@kernel.org>]

On 2/24/26 23:08, Niklas Cassel wrote:
> On Tue, Feb 24, 2026 at 11:06:38AM +0900, Damien Le Moal wrote:
>> When handling SCSI command timeouts, if we had no actual command
>> timeouts (either because the command was a deferred qc or the completion
>> path won the race with ata_scsi_cmd_error_handler()), we do not need to
>> go through a port error handling, as there was in fact no errors at all.
>>
>> Modify ata_scsi_cmd_error_handler() to return the number of commands
>> that timed out and use this return value in ata_scsi_error() to call
>> ata_scsi_port_error_handler() only if we had command timeouts, or if
>> the port EH has already been scheduled due to failed commands.
>> Otherwise, simply call scsi_eh_flush_done_q() to finish the completed
>> commands without running the full port error handling.
>>
>> Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
> 
> Reviewed-by: Niklas Cassel <cassel@kernel.org>
> 
> 
>> diff --git a/include/linux/libata.h b/include/linux/libata.h
>> index db87c99e4189..c872d1f9f43b 100644
>> --- a/include/linux/libata.h
>> +++ b/include/linux/libata.h
>> @@ -1225,7 +1225,8 @@ extern int ata_ncq_prio_enable(struct ata_port *ap, struct scsi_device *sdev,
>>  extern struct ata_device *ata_dev_pair(struct ata_device *adev);
>>  int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev);
>>  extern void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap);
>> -extern void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap, struct list_head *eh_q);
>> +extern int ata_scsi_cmd_error_handler(struct Scsi_Host *host,
>> +				struct ata_port *ap, struct list_head *eh_q);
> 
> Nit: we could drop the extern while touching this line anyway.

Sure. Can you fix that up when applying ?


-- 
Damien Le Moal
Western Digital Research