@@ -147,6 +147,8 @@ EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_wait);
* driver has to take blk-mq max supported nr_hw_queues into account
* when figuring out nr_hw_queues from hardware info, for avoiding
* inconsistency between driver and blk-mq.
+ *
+ * Limit to single queue in case of kdump kernel
*/
unsigned int blk_mq_max_nr_hw_queues(void)
{
@@ -4370,7 +4372,7 @@ static void blk_mq_update_queue_map(struct blk_mq_tag_set *set)
if (set->nr_maps == 1)
set->map[HCTX_TYPE_DEFAULT].nr_queues = set->nr_hw_queues;
- if (set->ops->map_queues && !is_kdump_kernel()) {
+ if (set->ops->map_queues) {
int i;
/*
@@ -4420,6 +4422,22 @@ static int blk_mq_realloc_tag_set_tags(struct blk_mq_tag_set *set,
return 0;
}
+/* Limit to single map in case of kdump kernel */
+static unsigned int blk_mq_max_nr_maps(void)
+{
+ if (is_kdump_kernel())
+ return 1;
+ return HCTX_MAX_TYPES;
+}
+
+/* Limit to 64 in case of kdump kernel */
+static unsigned int blk_mq_max_depth(void)
+{
+ if (is_kdump_kernel())
+ return 64;
+ return BLK_MQ_MAX_DEPTH;
+}
+
/*
* Alloc a tag set to be associated with one or more request queues.
* May fail with EINVAL for various error conditions. May adjust the
@@ -4456,16 +4474,13 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set)
else if (set->nr_maps > HCTX_MAX_TYPES)
return -EINVAL;
- /*
- * If a crashdump is active, then we are potentially in a very
- * memory constrained environment. Limit us to 1 queue and
- * 64 tags to prevent using too much memory.
- */
- if (is_kdump_kernel()) {
- set->nr_hw_queues = 1;
- set->nr_maps = 1;
- set->queue_depth = min(64U, set->queue_depth);
- }
+ if (set->nr_hw_queues > blk_mq_max_nr_hw_queues())
+ set->nr_hw_queues = blk_mq_max_nr_hw_queues();
+ if (set->nr_maps > blk_mq_max_nr_maps())
+ set->nr_maps = blk_mq_max_nr_maps();
+ if (set->queue_depth > blk_mq_max_depth())
+ set->queue_depth = blk_mq_max_depth();
+
/*
* There is no use for more h/w queues than cpus if we just have
* a single map
@@ -4495,7 +4510,7 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set)
GFP_KERNEL, set->numa_node);
if (!set->map[i].mq_map)
goto out_free_mq_map;
- set->map[i].nr_queues = is_kdump_kernel() ? 1 : set->nr_hw_queues;
+ set->map[i].nr_queues = set->nr_hw_queues;
}
blk_mq_update_queue_map(set);
Clean up code a bit by adding helpers for treating kdump kernel specially. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> --- block/blk-mq.c | 39 +++++++++++++++++++++++++++------------ 1 file changed, 27 insertions(+), 12 deletions(-)