From 5dc8b362a2374d007bc0db649b7ab6a79dd32bda Mon Sep 17 00:00:00 2001 From: Adam Manzanares Date: Mon, 17 Oct 2016 11:27:28 -0700 Subject: block: Add iocontext priority to request Patch adds an association between iocontext ioprio and the ioprio of a request. This is done to enable request based drivers the ability to act on priority information stored in the request. An example being ATA devices that support command priorities. If the ATA driver discovers that the device supports command priorities and the request has valid priority information indicating the request is high priority, then a high priority command can be sent to the device. This should improve tail latencies for high priority IO on any device that queues requests internally and can make use of the priority information stored in the request. The ioprio of the request is set in blk_rq_set_prio which takes the request and the ioc as arguments. If the ioc is valid in blk_rq_set_prio then the iopriority of the request is set as the iopriority of the ioc. In init_request_from_bio a check is made to see if the ioprio of the bio is valid and if so then the request prio comes from the bio. Signed-off-by: Adam Manzananares Reviewed-by: Jens Axboe Signed-off-by: Tejun Heo --- include/linux/blkdev.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'include') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index c47c358ba052..9a0ceaa1b7e6 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -933,6 +933,20 @@ static inline unsigned int blk_rq_count_bios(struct request *rq) return nr_bios; } +/* + * blk_rq_set_prio - associate a request with prio from ioc + * @rq: request of interest + * @ioc: target iocontext + * + * Assocate request prio with ioc prio so request based drivers + * can leverage priority information. + */ +static inline void blk_rq_set_prio(struct request *rq, struct io_context *ioc) +{ + if (ioc) + rq->ioprio = ioc->ioprio; +} + /* * Request issue related functions. */ -- cgit v1.2.3 From 8e061784b51ec4a4efed0deaafb5bd9725bf5b06 Mon Sep 17 00:00:00 2001 From: Adam Manzanares Date: Mon, 17 Oct 2016 11:27:29 -0700 Subject: ata: Enabling ATA Command Priorities This patch checks to see if an ATA device supports NCQ command priorities. If so and the user has specified an iocontext that indicates IO_PRIO_CLASS_RT then we build a tf with a high priority command. This is done to improve the tail latency of commands that are high priority by passing priority to the device. tj: Removed trivial ata_ncq_prio_enabled() and open-coded the test. Signed-off-by: Adam Manzanares Signed-off-by: Tejun Heo --- include/linux/ata.h | 6 ++++++ include/linux/libata.h | 3 +++ 2 files changed, 9 insertions(+) (limited to 'include') diff --git a/include/linux/ata.h b/include/linux/ata.h index fdb180367ba1..af6859b3a93d 100644 --- a/include/linux/ata.h +++ b/include/linux/ata.h @@ -348,6 +348,7 @@ enum { ATA_LOG_DEVSLP_DETO = 0x01, ATA_LOG_DEVSLP_VALID = 0x07, ATA_LOG_DEVSLP_VALID_MASK = 0x80, + ATA_LOG_NCQ_PRIO_OFFSET = 0x09, /* NCQ send and receive log */ ATA_LOG_NCQ_SEND_RECV_SUBCMDS_OFFSET = 0x00, @@ -940,6 +941,11 @@ static inline bool ata_id_has_ncq_non_data(const u16 *id) return id[ATA_ID_SATA_CAPABILITY_2] & BIT(5); } +static inline bool ata_id_has_ncq_prio(const u16 *id) +{ + return id[ATA_ID_SATA_CAPABILITY] & BIT(12); +} + static inline bool ata_id_has_trim(const u16 *id) { if (ata_id_major_version(id) >= 7 && diff --git a/include/linux/libata.h b/include/linux/libata.h index 616eef4d81ea..90b69a6293a3 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -166,6 +166,7 @@ enum { ATA_DFLAG_NO_UNLOAD = (1 << 17), /* device doesn't support unload */ ATA_DFLAG_UNLOCK_HPA = (1 << 18), /* unlock HPA */ ATA_DFLAG_NCQ_SEND_RECV = (1 << 19), /* device supports NCQ SEND and RECV */ + ATA_DFLAG_NCQ_PRIO = (1 << 20), /* device supports NCQ priority */ ATA_DFLAG_INIT_MASK = (1 << 24) - 1, ATA_DFLAG_DETACH = (1 << 24), @@ -342,7 +343,9 @@ enum { ATA_SHIFT_PIO = 0, ATA_SHIFT_MWDMA = ATA_SHIFT_PIO + ATA_NR_PIO_MODES, ATA_SHIFT_UDMA = ATA_SHIFT_MWDMA + ATA_NR_MWDMA_MODES, + ATA_SHIFT_PRIO = 6, + ATA_PRIO_HIGH = 2, /* size of buffer to pad xfers ending on unaligned boundaries */ ATA_DMA_PAD_SZ = 4, -- cgit v1.2.3 From 84f95243b5439a20c33837075b88926bfa00c4ec Mon Sep 17 00:00:00 2001 From: Adam Manzanares Date: Mon, 17 Oct 2016 11:27:30 -0700 Subject: ata: ATA Command Priority Disabled By Default Add a sysfs entry to turn on priority information being passed to a ATA device. By default this feature is turned off. This patch depends on ata: Enabling ATA Command Priorities tj: Renamed ncq_prio_on to ncq_prio_enable and removed trivial ata_ncq_prio_on() and open-coded the test. Signed-off-by: Adam Manzanares Signed-off-by: Tejun Heo --- include/linux/libata.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/libata.h b/include/linux/libata.h index 90b69a6293a3..c170be548b7f 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -167,6 +167,7 @@ enum { ATA_DFLAG_UNLOCK_HPA = (1 << 18), /* unlock HPA */ ATA_DFLAG_NCQ_SEND_RECV = (1 << 19), /* device supports NCQ SEND and RECV */ ATA_DFLAG_NCQ_PRIO = (1 << 20), /* device supports NCQ priority */ + ATA_DFLAG_NCQ_PRIO_ENABLE = (1 << 21), /* Priority cmds sent to dev */ ATA_DFLAG_INIT_MASK = (1 << 24) - 1, ATA_DFLAG_DETACH = (1 << 24), @@ -545,6 +546,7 @@ typedef void (*ata_postreset_fn_t)(struct ata_link *link, unsigned int *classes) extern struct device_attribute dev_attr_link_power_management_policy; extern struct device_attribute dev_attr_unload_heads; +extern struct device_attribute dev_attr_ncq_prio_enable; extern struct device_attribute dev_attr_em_message_type; extern struct device_attribute dev_attr_em_message; extern struct device_attribute dev_attr_sw_activity; -- cgit v1.2.3 From a2e7eefd5618e0f75bae2eb5c9387ea2f627b6ca Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 2 Dec 2016 19:31:01 +0100 Subject: nvme: move NVMe class code to pci_ids.h We'll need to check for it in the AHCI drivers (yes, really) soon. Signed-off-by: Christoph Hellwig Signed-off-by: Tejun Heo --- include/linux/pci_ids.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h index c58752fe16c4..a5e6c7bca610 100644 --- a/include/linux/pci_ids.h +++ b/include/linux/pci_ids.h @@ -23,8 +23,10 @@ #define PCI_CLASS_STORAGE_SATA 0x0106 #define PCI_CLASS_STORAGE_SATA_AHCI 0x010601 #define PCI_CLASS_STORAGE_SAS 0x0107 +#define PCI_CLASS_STORAGE_EXPRESS 0x010802 #define PCI_CLASS_STORAGE_OTHER 0x0180 + #define PCI_BASE_CLASS_NETWORK 0x02 #define PCI_CLASS_NETWORK_ETHERNET 0x0200 #define PCI_CLASS_NETWORK_TOKEN_RING 0x0201 -- cgit v1.2.3 From bfa9cb3e110cc02f2120e021bc853773bfd61b74 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Fri, 2 Dec 2016 19:31:02 +0100 Subject: ahci-remap.h: add ahci remapping definitions Signed-off-by: Dan Williams [hch: split into a separate header and commit] Signed-off-by: Christoph Hellwig [tj: dropped duplicate definition of AHCI_VSCAP spotted by Sergei] Cc: Sergei Shtylyov Signed-off-by: Tejun Heo --- include/linux/ahci-remap.h | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) create mode 100644 include/linux/ahci-remap.h (limited to 'include') diff --git a/include/linux/ahci-remap.h b/include/linux/ahci-remap.h new file mode 100644 index 000000000000..62be3a40239d --- /dev/null +++ b/include/linux/ahci-remap.h @@ -0,0 +1,28 @@ +#ifndef _LINUX_AHCI_REMAP_H +#define _LINUX_AHCI_REMAP_H + +#include + +#define AHCI_VSCAP 0xa4 +#define AHCI_REMAP_CAP 0x800 + +/* device class code */ +#define AHCI_REMAP_N_DCC 0x880 + +/* remap-device base relative to ahci-bar */ +#define AHCI_REMAP_N_OFFSET SZ_16K +#define AHCI_REMAP_N_SIZE SZ_16K + +#define AHCI_MAX_REMAP 3 + +static inline unsigned int ahci_remap_dcc(int i) +{ + return AHCI_REMAP_N_DCC + i * 0x80; +} + +static inline unsigned int ahci_remap_base(int i) +{ + return AHCI_REMAP_N_OFFSET + i * AHCI_REMAP_N_SIZE; +} + +#endif /* _LINUX_AHCI_REMAP_H */ -- cgit v1.2.3