From a9ed3aa9b87ee41e8ab3ff471b1331c154767e45 Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Sat, 26 Sep 2026 07:57:59 +1000 Subject: Merge tag 'drm-misc-fixes-2026-09-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes A number of fixes: - bridge: - samsung-dsim: fix GPIO lifetime - client: Null pointer dereference fix - imagination: error handling fix, page handling fix - nouveau: fix reference leaks, double-frees, out-of-bounds accesses, use-after-frees, don't reject config without SCDC, a number of workarounds - virtio: fix memory leak, reference leaks, null pointer dereference, add pixel blend mode, cache coherency fix Signed-off-by: Dave Airlie From: Maxime Ripard Link: https://patch.msgid.link/arU22zzqUGDEco1y@houat --- .../admin-guide/device-mapper/dm-queue-length.rst | 48 ++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 Documentation/admin-guide/device-mapper/dm-queue-length.rst (limited to 'Documentation/admin-guide/device-mapper/dm-queue-length.rst') diff --git a/Documentation/admin-guide/device-mapper/dm-queue-length.rst b/Documentation/admin-guide/device-mapper/dm-queue-length.rst new file mode 100644 index 000000000..d8e381c1c --- /dev/null +++ b/Documentation/admin-guide/device-mapper/dm-queue-length.rst @@ -0,0 +1,48 @@ +=============== +dm-queue-length +=============== + +dm-queue-length is a path selector module for device-mapper targets, +which selects a path with the least number of in-flight I/Os. +The path selector name is 'queue-length'. + +Table parameters for each path: [] + +:: + + : The number of I/Os to dispatch using the selected + path before switching to the next path. + If not given, internal default is used. To check + the default value, see the activated table. + +Status for each path: + +:: + + : 'A' if the path is active, 'F' if the path is failed. + : The number of path failures. + : The number of in-flight I/Os on the path. + + +Algorithm +========= + +dm-queue-length increments/decrements 'in-flight' when an I/O is +dispatched/completed respectively. +dm-queue-length selects a path with the minimum 'in-flight'. + + +Examples +======== +In case that 2 paths (sda and sdb) are used with repeat_count == 128. + +:: + + # echo "0 10 multipath 0 0 1 1 queue-length 0 2 1 8:0 128 8:16 128" \ + dmsetup create test + # + # dmsetup table + test: 0 10 multipath 0 0 1 1 queue-length 0 2 1 8:0 128 8:16 128 + # + # dmsetup status + test: 0 10 multipath 2 0 0 0 1 1 E 0 2 1 8:0 A 0 0 8:16 A 0 0 -- cgit v1.3.1