This is a note to let you know that I've just added the patch titled
blk-mq: Include all present CPUs in the default queue mapping
to the 4.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
blk-mq-include-all-present-cpus-in-the-default-queue-mapping.patch
and it can be found in the queue-4.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 5f042e7cbd9ebd3580077dcdc21f35e68c2adf5f Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@xxxxxx>
Date: Mon, 26 Jun 2017 12:20:56 +0200
Subject: blk-mq: Include all present CPUs in the default queue mapping
From: Christoph Hellwig <hch@xxxxxx>
commit 5f042e7cbd9ebd3580077dcdc21f35e68c2adf5f upstream.
This way we get a nice distribution independent of the current cpu
online / offline state.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Jens Axboe <axboe@xxxxxxxxx>
Cc: Keith Busch <keith.busch@xxxxxxxxx>
Cc: linux-block@xxxxxxxxxxxxxxx
Cc: linux-nvme@xxxxxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20170626102058.10200-2-hch@xxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
block/blk-mq-cpumap.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
--- a/block/blk-mq-cpumap.c
+++ b/block/blk-mq-cpumap.c
@@ -35,7 +35,6 @@ int blk_mq_map_queues(struct blk_mq_tag_
{
unsigned int *map = set->mq_map;
unsigned int nr_queues = set->nr_hw_queues;
- const struct cpumask *online_mask = cpu_online_mask;
unsigned int i, nr_cpus, nr_uniq_cpus, queue, first_sibling;
cpumask_var_t cpus;
@@ -44,7 +43,7 @@ int blk_mq_map_queues(struct blk_mq_tag_
cpumask_clear(cpus);
nr_cpus = nr_uniq_cpus = 0;
- for_each_cpu(i, online_mask) {
+ for_each_present_cpu(i) {
nr_cpus++;
first_sibling = get_first_sibling(i);
if (!cpumask_test_cpu(first_sibling, cpus))
@@ -54,7 +53,7 @@ int blk_mq_map_queues(struct blk_mq_tag_
queue = 0;
for_each_possible_cpu(i) {
- if (!cpumask_test_cpu(i, online_mask)) {
+ if (!cpumask_test_cpu(i, cpu_present_mask)) {
map[i] = 0;
continue;
}
Patches currently in stable-queue which might be from hch@xxxxxx are
queue-4.12/block-disable-runtime-pm-for-blk-mq.patch
queue-4.12/blk-mq-create-hctx-for-each-present-cpu.patch
queue-4.12/blk-mq-include-all-present-cpus-in-the-default-queue-mapping.patch