[PATCH v4 2/6] block: improve ioprio class description comment
From: Damien Le Moal <hidden>
Date: 2021-08-11 03:37:26
Also in:
linux-f2fs-devel
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
In include/usapi/linux/ioprio.h, change the ioprio class enum comment to remove the outdated reference to CFQ and mention BFQ and mq-deadline instead. Also document the high priority NCQ command use for RT class IOs directed at ATA drives that support NCQ priority. Signed-off-by: Damien Le Moal <redacted> --- include/uapi/linux/ioprio.h | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/include/uapi/linux/ioprio.h b/include/uapi/linux/ioprio.h
index 77b17e08b0da..6b735854aebd 100644
--- a/include/uapi/linux/ioprio.h
+++ b/include/uapi/linux/ioprio.h@@ -13,10 +13,12 @@ #define IOPRIO_PRIO_VALUE(class, data) (((class) << IOPRIO_CLASS_SHIFT) | data) /* - * These are the io priority groups as implemented by CFQ. RT is the realtime - * class, it always gets premium service. BE is the best-effort scheduling - * class, the default for any process. IDLE is the idle scheduling class, it - * is only served when no one else is using the disk. + * These are the io priority groups as implemented by the BFQ and mq-deadline + * schedulers. RT is the realtime class, it always gets premium service. For + * ATA disks supporting NCQ IO priority, RT class IOs will be processed using + * high priority NCQ commands. BE is the best-effort scheduling class, the + * default for any process. IDLE is the idle scheduling class, it is only + * served when no one else is using the disk. */ enum { IOPRIO_CLASS_NONE,
--
2.31.1