[PATCH 23/28] sbitmap.h: move declarations to sbitmap_types.h

From: Max Kellermann
Date: Wed Jan 31 2024 - 09:56:38 EST


By providing declarations in a lean header, we can reduce header
dependencies.

Signed-off-by: Max Kellermann <max.kellermann@xxxxxxxxx>
---
block/blk-mq.h | 1 +
include/linux/blk-mq.h | 2 +-
include/linux/sbitmap.h | 124 +-------------------------------
include/linux/sbitmap_types.h | 129 ++++++++++++++++++++++++++++++++++
4 files changed, 132 insertions(+), 124 deletions(-)
create mode 100644 include/linux/sbitmap_types.h

diff --git a/block/blk-mq.h b/block/blk-mq.h
index f75a9ecfebde..cc8e690171db 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -3,6 +3,7 @@
#define INT_BLK_MQ_H

#include <linux/blk-mq.h>
+#include <linux/sbitmap.h>
#include "blk-stat.h"

struct blk_mq_tag_set;
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index ed3760b04baa..201ee354a3d5 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -4,7 +4,7 @@

#include <linux/bio.h>
#include <linux/blkdev.h>
-#include <linux/sbitmap.h>
+#include <linux/sbitmap_types.h>
#include <linux/lockdep_types.h>
#include <linux/scatterlist.h>
#include <linux/prefetch.h>
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
index f7279f7632fe..c43d1c0eafbb 100644
--- a/include/linux/sbitmap.h
+++ b/include/linux/sbitmap.h
@@ -9,142 +9,20 @@
#ifndef __LINUX_SCALE_BITMAP_H
#define __LINUX_SCALE_BITMAP_H

+#include <linux/sbitmap_types.h>
#include <linux/atomic.h>
#include <linux/bitops.h>
-#include <linux/cache.h>
#include <linux/list.h>
#include <linux/log2.h>
#include <linux/minmax.h>
#include <linux/percpu.h>
#include <linux/slab.h>
-#include <linux/types.h>
-#include <linux/wait_types.h>

struct seq_file;

-/**
- * struct sbitmap_word - Word in a &struct sbitmap.
- */
-struct sbitmap_word {
- /**
- * @word: word holding free bits
- */
- unsigned long word;
-
- /**
- * @cleared: word holding cleared bits
- */
- unsigned long cleared ____cacheline_aligned_in_smp;
-} ____cacheline_aligned_in_smp;
-
-/**
- * struct sbitmap - Scalable bitmap.
- *
- * A &struct sbitmap is spread over multiple cachelines to avoid ping-pong. This
- * trades off higher memory usage for better scalability.
- */
-struct sbitmap {
- /**
- * @depth: Number of bits used in the whole bitmap.
- */
- unsigned int depth;
-
- /**
- * @shift: log2(number of bits used per word)
- */
- unsigned int shift;
-
- /**
- * @map_nr: Number of words (cachelines) being used for the bitmap.
- */
- unsigned int map_nr;
-
- /**
- * @round_robin: Allocate bits in strict round-robin order.
- */
- bool round_robin;
-
- /**
- * @map: Allocated bitmap.
- */
- struct sbitmap_word *map;
-
- /*
- * @alloc_hint: Cache of last successfully allocated or freed bit.
- *
- * This is per-cpu, which allows multiple users to stick to different
- * cachelines until the map is exhausted.
- */
- unsigned int __percpu *alloc_hint;
-};
-
#define SBQ_WAIT_QUEUES 8
#define SBQ_WAKE_BATCH 8

-/**
- * struct sbq_wait_state - Wait queue in a &struct sbitmap_queue.
- */
-struct sbq_wait_state {
- /**
- * @wait: Wait queue.
- */
- wait_queue_head_t wait;
-} ____cacheline_aligned_in_smp;
-
-/**
- * struct sbitmap_queue - Scalable bitmap with the added ability to wait on free
- * bits.
- *
- * A &struct sbitmap_queue uses multiple wait queues and rolling wakeups to
- * avoid contention on the wait queue spinlock. This ensures that we don't hit a
- * scalability wall when we run out of free bits and have to start putting tasks
- * to sleep.
- */
-struct sbitmap_queue {
- /**
- * @sb: Scalable bitmap.
- */
- struct sbitmap sb;
-
- /**
- * @wake_batch: Number of bits which must be freed before we wake up any
- * waiters.
- */
- unsigned int wake_batch;
-
- /**
- * @wake_index: Next wait queue in @ws to wake up.
- */
- atomic_t wake_index;
-
- /**
- * @ws: Wait queues.
- */
- struct sbq_wait_state *ws;
-
- /*
- * @ws_active: count of currently active ws waitqueues
- */
- atomic_t ws_active;
-
- /**
- * @min_shallow_depth: The minimum shallow depth which may be passed to
- * sbitmap_queue_get_shallow()
- */
- unsigned int min_shallow_depth;
-
- /**
- * @completion_cnt: Number of bits cleared passed to the
- * wakeup function.
- */
- atomic_t completion_cnt;
-
- /**
- * @wakeup_cnt: Number of thread wake ups issued.
- */
- atomic_t wakeup_cnt;
-};
-
/**
* sbitmap_init_node() - Initialize a &struct sbitmap on a specific memory node.
* @sb: Bitmap to initialize.
diff --git a/include/linux/sbitmap_types.h b/include/linux/sbitmap_types.h
new file mode 100644
index 000000000000..078c7859905c
--- /dev/null
+++ b/include/linux/sbitmap_types.h
@@ -0,0 +1,129 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __LINUX_SCALE_BITMAP_TYPES_H
+#define __LINUX_SCALE_BITMAP_TYPES_H
+
+#include <linux/cache.h>
+#include <linux/types.h>
+#include <linux/wait_types.h>
+
+/**
+ * struct sbitmap_word - Word in a &struct sbitmap.
+ */
+struct sbitmap_word {
+ /**
+ * @word: word holding free bits
+ */
+ unsigned long word;
+
+ /**
+ * @cleared: word holding cleared bits
+ */
+ unsigned long cleared ____cacheline_aligned_in_smp;
+} ____cacheline_aligned_in_smp;
+
+/**
+ * struct sbitmap - Scalable bitmap.
+ *
+ * A &struct sbitmap is spread over multiple cachelines to avoid ping-pong. This
+ * trades off higher memory usage for better scalability.
+ */
+struct sbitmap {
+ /**
+ * @depth: Number of bits used in the whole bitmap.
+ */
+ unsigned int depth;
+
+ /**
+ * @shift: log2(number of bits used per word)
+ */
+ unsigned int shift;
+
+ /**
+ * @map_nr: Number of words (cachelines) being used for the bitmap.
+ */
+ unsigned int map_nr;
+
+ /**
+ * @round_robin: Allocate bits in strict round-robin order.
+ */
+ bool round_robin;
+
+ /**
+ * @map: Allocated bitmap.
+ */
+ struct sbitmap_word *map;
+
+ /*
+ * @alloc_hint: Cache of last successfully allocated or freed bit.
+ *
+ * This is per-cpu, which allows multiple users to stick to different
+ * cachelines until the map is exhausted.
+ */
+ unsigned int __percpu *alloc_hint;
+};
+
+/**
+ * struct sbq_wait_state - Wait queue in a &struct sbitmap_queue.
+ */
+struct sbq_wait_state {
+ /**
+ * @wait: Wait queue.
+ */
+ wait_queue_head_t wait;
+} ____cacheline_aligned_in_smp;
+
+/**
+ * struct sbitmap_queue - Scalable bitmap with the added ability to wait on free
+ * bits.
+ *
+ * A &struct sbitmap_queue uses multiple wait queues and rolling wakeups to
+ * avoid contention on the wait queue spinlock. This ensures that we don't hit a
+ * scalability wall when we run out of free bits and have to start putting tasks
+ * to sleep.
+ */
+struct sbitmap_queue {
+ /**
+ * @sb: Scalable bitmap.
+ */
+ struct sbitmap sb;
+
+ /**
+ * @wake_batch: Number of bits which must be freed before we wake up any
+ * waiters.
+ */
+ unsigned int wake_batch;
+
+ /**
+ * @wake_index: Next wait queue in @ws to wake up.
+ */
+ atomic_t wake_index;
+
+ /**
+ * @ws: Wait queues.
+ */
+ struct sbq_wait_state *ws;
+
+ /*
+ * @ws_active: count of currently active ws waitqueues
+ */
+ atomic_t ws_active;
+
+ /**
+ * @min_shallow_depth: The minimum shallow depth which may be passed to
+ * sbitmap_queue_get_shallow()
+ */
+ unsigned int min_shallow_depth;
+
+ /**
+ * @completion_cnt: Number of bits cleared passed to the
+ * wakeup function.
+ */
+ atomic_t completion_cnt;
+
+ /**
+ * @wakeup_cnt: Number of thread wake ups issued.
+ */
+ atomic_t wakeup_cnt;
+};
+
+#endif /* __LINUX_SCALE_BITMAP_TYPES_H */
--
2.39.2