James Bottomley wrote:
On Tue, 2010-09-21 at 14:17 -0500, David Milburn wrote:Non-NCQ commands should run exclusively, ata_qc_issue warns when mixing non-NCQ and NCQ commands. Signed-off-by: David Milburn <dmilburn@xxxxxxxxxx> Reported-by: Konstantinos Skarlatos <k.skarlatos@xxxxxxxxx> --- drivers/scsi/libsas/sas_ata.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c index 042153c..ddbade7 100644 --- a/drivers/scsi/libsas/sas_ata.c +++ b/drivers/scsi/libsas/sas_ata.c @@ -347,6 +347,7 @@ static int sas_ata_scr_read(struct ata_link *link, unsigned int sc_reg_in, static struct ata_port_operations sas_sata_ops = { .phy_reset = sas_ata_phy_reset, .post_internal_cmd = sas_ata_post_internal, + .qc_defer = ata_std_qc_defer,What does this do on the card that doesn't need it: the aic94xx? That one takes in a pipeline of commands and takes responsibility for getting the issue right. Something like this throttles the pipeline higher than the aic94xx is expecting. However, as long as it's not too much of a performance problem, I don't mind applying it.
James, For any driver using sas_sata_ops, it could effect performance for those drivers whose execute_task handles both, though I can't say I am real familiar with aic94xx. Thanks, David
James
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