blk-mq: move tags and sched_tags info from sysfs to debugfs
These are very tied to the blk-mq tag implementation, so exposing them
to sysfs isn't a great idea. Move the debugging information to debugfs
and add basic entries for the number of tags and the number of reserved
tags to sysfs.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 857bdad..9f81100 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -20,6 +20,7 @@
#include <linux/blk-mq.h>
#include "blk-mq.h"
+#include "blk-mq-tag.h"
struct blk_mq_debugfs_attr {
const char *name;
@@ -154,6 +155,73 @@
.release = single_release,
};
+static void blk_mq_debugfs_tags_show(struct seq_file *m,
+ struct blk_mq_tags *tags)
+{
+ seq_printf(m, "nr_tags=%u\n", tags->nr_tags);
+ seq_printf(m, "nr_reserved_tags=%u\n", tags->nr_reserved_tags);
+ seq_printf(m, "active_queues=%d\n",
+ atomic_read(&tags->active_queues));
+
+ seq_puts(m, "\nbitmap_tags:\n");
+ sbitmap_queue_show(&tags->bitmap_tags, m);
+
+ if (tags->nr_reserved_tags) {
+ seq_puts(m, "\nbreserved_tags:\n");
+ sbitmap_queue_show(&tags->breserved_tags, m);
+ }
+}
+
+static int hctx_tags_show(struct seq_file *m, void *v)
+{
+ struct blk_mq_hw_ctx *hctx = m->private;
+ struct request_queue *q = hctx->queue;
+
+ mutex_lock(&q->sysfs_lock);
+ if (hctx->tags)
+ blk_mq_debugfs_tags_show(m, hctx->tags);
+ mutex_unlock(&q->sysfs_lock);
+
+ return 0;
+}
+
+static int hctx_tags_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, hctx_tags_show, inode->i_private);
+}
+
+static const struct file_operations hctx_tags_fops = {
+ .open = hctx_tags_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int hctx_sched_tags_show(struct seq_file *m, void *v)
+{
+ struct blk_mq_hw_ctx *hctx = m->private;
+ struct request_queue *q = hctx->queue;
+
+ mutex_lock(&q->sysfs_lock);
+ if (hctx->sched_tags)
+ blk_mq_debugfs_tags_show(m, hctx->sched_tags);
+ mutex_unlock(&q->sysfs_lock);
+
+ return 0;
+}
+
+static int hctx_sched_tags_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, hctx_sched_tags_show, inode->i_private);
+}
+
+static const struct file_operations hctx_sched_tags_fops = {
+ .open = hctx_sched_tags_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
static void *ctx_rq_list_start(struct seq_file *m, loff_t *pos)
{
struct blk_mq_ctx *ctx = m->private;
@@ -200,6 +268,8 @@
{"flags", 0400, &hctx_flags_fops},
{"dispatch", 0400, &hctx_dispatch_fops},
{"ctx_map", 0400, &hctx_ctx_map_fops},
+ {"tags", 0400, &hctx_tags_fops},
+ {"sched_tags", 0400, &hctx_sched_tags_fops},
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = {