On 2021/09/01 13:52, Kate Hsuan wrote: > Many users are reporting that the Samsung 860 and 870 SSD are having > various issues when combined with AMD SATA controllers and only > completely disabling NCQ helps to avoid these issues. > > Always disabling NCQ for Samsung 860/870 SSDs regardless of the host > SATA adapter vendor will cause I/O performance degradation with well > behaved adapters. To limit the performance impact to AMD adapters, > introduce the ATA_HORKAGE_NO_NCQ_ON_AMD flag to force disable NCQ > only for these adapters. > > BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=201693 > Signed-off-by: Kate Hsuan <hpa@xxxxxxxxxx> > --- > Changes in v4: > * A function ata_dev_check_adapter() is added to check the vendor ID of > the adapter. > * ATA_HORKAGE_NONCQ_ON_AMD was modified to ATA_HORKAGE_NO_NCQ_ON_AMD to > align with the naming??convention. > * Commit messages were improved according??to reviewer comments. > > Changes in v3: > * ATA_HORKAGE_NONCQ_ON_ASMEDIA_AMD_MARVELL was modified to > ATA_HORKAGE_NONCQ_ON_AMD. > * Codes were fixed to completely disable NCQ on AMD controller. > > --- > drivers/ata/libata-core.c | 32 ++++++++++++++++++++++++++++++-- > include/linux/libata.h | 1 + > 2 files changed, 31 insertions(+), 2 deletions(-) > > diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c > index c861c93d1e84..49049cd713e4 100644 > --- a/drivers/ata/libata-core.c > +++ b/drivers/ata/libata-core.c > @@ -2186,6 +2186,25 @@ static void ata_dev_config_ncq_prio(struct ata_device *dev) > dev->flags &= ~ATA_DFLAG_NCQ_PRIO; > } > > +static bool ata_dev_check_adapter(struct ata_device *dev, > + unsigned short vendor_id) > +{ > + struct pci_dev *pcidev = NULL; > + struct device *parent_dev = NULL; > + > + for (parent_dev = dev->tdev.parent; parent_dev != NULL; > + parent_dev = parent_dev->parent) { > + if (dev_is_pci(parent_dev)) { > + pcidev = to_pci_dev(parent_dev); > + if (pcidev->vendor == vendor_id) > + return true; > + break; > + } > + } > + > + return false; > +} > + > static int ata_dev_config_ncq(struct ata_device *dev, > char *desc, size_t desc_sz) > { > @@ -2204,6 +2223,13 @@ static int ata_dev_config_ncq(struct ata_device *dev, > snprintf(desc, desc_sz, "NCQ (not used)"); > return 0; > } > + > + if (dev->horkage & ATA_HORKAGE_NO_NCQ_ON_AMD && > + ata_dev_check_adapter(dev, PCI_VENDOR_ID_AMD)) { > + snprintf(desc, desc_sz, "NCQ (not used)"); > + return 0; > + } > + > if (ap->flags & ATA_FLAG_NCQ) { > hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE); > dev->flags |= ATA_DFLAG_NCQ; > @@ -3971,9 +3997,11 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = { > { "Samsung SSD 850*", NULL, ATA_HORKAGE_NO_NCQ_TRIM | > ATA_HORKAGE_ZERO_AFTER_TRIM, }, > { "Samsung SSD 860*", NULL, ATA_HORKAGE_NO_NCQ_TRIM | > - ATA_HORKAGE_ZERO_AFTER_TRIM, }, > + ATA_HORKAGE_ZERO_AFTER_TRIM | > + ATA_HORKAGE_NO_NCQ_ON_AMD, }, > { "Samsung SSD 870*", NULL, ATA_HORKAGE_NO_NCQ_TRIM | > - ATA_HORKAGE_ZERO_AFTER_TRIM, }, > + ATA_HORKAGE_ZERO_AFTER_TRIM | > + ATA_HORKAGE_NO_NCQ_ON_AMD, }, > { "FCCT*M500*", NULL, ATA_HORKAGE_NO_NCQ_TRIM | > ATA_HORKAGE_ZERO_AFTER_TRIM, }, > > diff --git a/include/linux/libata.h b/include/linux/libata.h > index 860e63f5667b..cdc248a15763 100644 > --- a/include/linux/libata.h > +++ b/include/linux/libata.h > @@ -426,6 +426,7 @@ enum { > ATA_HORKAGE_NOTRIM = (1 << 24), /* don't use TRIM */ > ATA_HORKAGE_MAX_SEC_1024 = (1 << 25), /* Limit max sects to 1024 */ > ATA_HORKAGE_MAX_TRIM_128M = (1 << 26), /* Limit max trim size to 128M */ > + ATA_HORKAGE_NO_NCQ_ON_AMD = (1 << 27), /* Disable NCQ on AMD chipset */ > > /* DMA mask for user DMA control: User visible values; DO NOT > renumber */ > -- > 2.31.1 > > Looks good to me. Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxx> -- Damien Le Moal Western Digital Research
