block: only build the icq tracking code when needed

Only bfq needs to code to track icq, so make it conditional.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211209063131.18537-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/Kconfig b/block/Kconfig
index c6ce41a..d5d4197 100644 (file)
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -35,6 +35,9 @@ config BLK_CGROUP_RWSTAT
 config BLK_DEV_BSG_COMMON
        tristate
 
+config BLK_ICQ
+       bool
+
 config BLK_DEV_BSGLIB
        bool "Block layer SG support v4 helper lib"
        select BLK_DEV_BSG_COMMON

diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched
index 885fee8..6155161 100644 (file)
--- a/block/Kconfig.iosched
+++ b/block/Kconfig.iosched
@@ -18,6 +18,7 @@ config MQ_IOSCHED_KYBER
 
 config IOSCHED_BFQ
        tristate "BFQ I/O scheduler"
+       select BLK_ICQ
        help
        BFQ I/O scheduler for BLK-MQ. BFQ distributes the bandwidth of
        of the device among all processes according to their weights,

diff --git a/block/blk-ioc.c b/block/blk-ioc.c
index dc7fb06..87bdc9c 100644 (file)
--- a/block/blk-ioc.c
+++ b/block/blk-ioc.c
@@ -19,6 +19,7 @@
  */
 static struct kmem_cache *iocontext_cachep;
 
+#ifdef CONFIG_BLK_ICQ
 /**
  * get_io_context - increment reference count to io_context
  * @ioc: io_context to get
@@ -163,6 +164,42 @@ static bool ioc_delay_free(struct io_context *ioc)
 }
 
 /**
+ * ioc_clear_queue - break any ioc association with the specified queue
+ * @q: request_queue being cleared
+ *
+ * Walk @q->icq_list and exit all io_cq's.
+ */
+void ioc_clear_queue(struct request_queue *q)
+{
+       LIST_HEAD(icq_list);
+
+       spin_lock_irq(&q->queue_lock);
+       list_splice_init(&q->icq_list, &icq_list);
+       spin_unlock_irq(&q->queue_lock);
+
+       rcu_read_lock();
+       while (!list_empty(&icq_list)) {
+               struct io_cq *icq =
+                       list_entry(icq_list.next, struct io_cq, q_node);
+
+               spin_lock_irq(&icq->ioc->lock);
+               if (!(icq->flags & ICQ_DESTROYED))
+                       ioc_destroy_icq(icq);
+               spin_unlock_irq(&icq->ioc->lock);
+       }
+       rcu_read_unlock();
+}
+#else /* CONFIG_BLK_ICQ */
+static inline void ioc_exit_icqs(struct io_context *ioc)
+{
+}
+static inline bool ioc_delay_free(struct io_context *ioc)
+{
+       return false;
+}
+#endif /* CONFIG_BLK_ICQ */
+
+/**
  * put_io_context - put a reference of io_context
  * @ioc: io_context to put
  *
@@ -193,33 +230,6 @@ void exit_io_context(struct task_struct *task)
        }
 }
 
-/**
- * ioc_clear_queue - break any ioc association with the specified queue
- * @q: request_queue being cleared
- *
- * Walk @q->icq_list and exit all io_cq's.
- */
-void ioc_clear_queue(struct request_queue *q)
-{
-       LIST_HEAD(icq_list);
-
-       spin_lock_irq(&q->queue_lock);
-       list_splice_init(&q->icq_list, &icq_list);
-       spin_unlock_irq(&q->queue_lock);
-
-       rcu_read_lock();
-       while (!list_empty(&icq_list)) {
-               struct io_cq *icq =
-                       list_entry(icq_list.next, struct io_cq, q_node);
-
-               spin_lock_irq(&icq->ioc->lock);
-               if (!(icq->flags & ICQ_DESTROYED))
-                       ioc_destroy_icq(icq);
-               spin_unlock_irq(&icq->ioc->lock);
-       }
-       rcu_read_unlock();
-}
-
 static struct io_context *alloc_io_context(gfp_t gfp_flags, int node)
 {
        struct io_context *ioc;
@@ -231,10 +241,12 @@ static struct io_context *alloc_io_context(gfp_t gfp_flags, int node)
 
        atomic_long_set(&ioc->refcount, 1);
        atomic_set(&ioc->active_ref, 1);
+#ifdef CONFIG_BLK_ICQ
        spin_lock_init(&ioc->lock);
        INIT_RADIX_TREE(&ioc->icq_tree, GFP_ATOMIC);
        INIT_HLIST_HEAD(&ioc->icq_list);
        INIT_WORK(&ioc->release_work, ioc_release_fn);
+#endif
        return ioc;
 }
 
@@ -300,6 +312,7 @@ int __copy_io(unsigned long clone_flags, struct task_struct *tsk)
        return 0;
 }
 
+#ifdef CONFIG_BLK_ICQ
 /**
  * ioc_lookup_icq - lookup io_cq from ioc
  * @q: the associated request_queue
@@ -428,6 +441,7 @@ struct io_cq *ioc_find_get_icq(struct request_queue *q)
        return icq;
 }
 EXPORT_SYMBOL_GPL(ioc_find_get_icq);
+#endif /* CONFIG_BLK_ICQ */
 
 static int __init blk_ioc_init(void)
 {

diff --git a/block/blk.h b/block/blk.h
index 7ccb7c7..8bd43b3 100644 (file)
--- a/block/blk.h
+++ b/block/blk.h
@@ -366,7 +366,13 @@ static inline unsigned int bio_aligned_discard_max_sectors(
  */
 struct io_cq *ioc_find_get_icq(struct request_queue *q);
 struct io_cq *ioc_lookup_icq(struct request_queue *q);
+#ifdef CONFIG_BLK_ICQ
 void ioc_clear_queue(struct request_queue *q);
+#else
+static inline void ioc_clear_queue(struct request_queue *q)
+{
+}
+#endif /* CONFIG_BLK_ICQ */
 
 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
 extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page);

diff --git a/include/linux/iocontext.h b/include/linux/iocontext.h
index 648331f..14f7eaf 100644 (file)
--- a/include/linux/iocontext.h
+++ b/include/linux/iocontext.h
@@ -100,16 +100,18 @@ struct io_context {
        atomic_long_t refcount;
        atomic_t active_ref;
 
+       unsigned short ioprio;
+
+#ifdef CONFIG_BLK_ICQ
        /* all the fields below are protected by this lock */
        spinlock_t lock;
 
-       unsigned short ioprio;
-
        struct radix_tree_root  icq_tree;
        struct io_cq __rcu      *icq_hint;
        struct hlist_head       icq_list;
 
        struct work_struct release_work;
+#endif /* CONFIG_BLK_ICQ */
 };
 
 struct task_struct;