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/libata.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/libata.h') 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 v1.2.3-70-g09d2