From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
The eXtensible Bitmap is a sparse bitmap representation which is
efficient for set bits which tend to cluster. It supports up to
'unsigned long' worth of bits.
Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
Signed-off-by: Wei Wang <wei.w.wang@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
Cc: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
---
include/linux/xbitmap.h | 48 ++++
lib/Makefile | 2 +-
lib/radix-tree.c | 38 ++-
lib/xbitmap.c | 444 +++++++++++++++++++++++++++++++
tools/include/linux/bitmap.h | 34 +++
tools/include/linux/kernel.h | 2 +
tools/testing/radix-tree/Makefile | 17 +-
tools/testing/radix-tree/linux/kernel.h | 2 -
tools/testing/radix-tree/linux/xbitmap.h | 1 +
tools/testing/radix-tree/main.c | 4 +
tools/testing/radix-tree/test.h | 1 +
11 files changed, 583 insertions(+), 10 deletions(-)
create mode 100644 include/linux/xbitmap.h
create mode 100644 lib/xbitmap.c
create mode 100644 tools/testing/radix-tree/linux/xbitmap.h
diff --git a/include/linux/xbitmap.h b/include/linux/xbitmap.h
new file mode 100644
index 0000000..c008309
--- /dev/null
+++ b/include/linux/xbitmap.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * eXtensible Bitmaps
+ * Copyright (c) 2017 Microsoft Corporation
+ * Author: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
+ *
+ * eXtensible Bitmaps provide an unlimited-size sparse bitmap facility.
+ * All bits are initially zero.
+ *
+ * Locking is to be provided by the user. No xb_ function is safe to
+ * call concurrently with any other xb_ function.
+ */
+
+#include <linux/idr.h>
+
+struct xb {
+ struct radix_tree_root xbrt;
+};
+
+#define XB_INIT { \
+ .xbrt = RADIX_TREE_INIT(IDR_RT_MARKER | GFP_NOWAIT), \
+}
+#define DEFINE_XB(name) struct xb name = XB_INIT
+
+static inline void xb_init(struct xb *xb)
+{
+ INIT_RADIX_TREE(&xb->xbrt, IDR_RT_MARKER | GFP_NOWAIT);
+}
+
+int xb_set_bit(struct xb *xb, unsigned long bit);
+bool xb_test_bit(const struct xb *xb, unsigned long bit);
+void xb_clear_bit(struct xb *xb, unsigned long bit);
+void xb_zero(struct xb *xb, unsigned long min, unsigned long max);
+void xb_fill(struct xb *xb, unsigned long min, unsigned long max);
+bool xb_find_set(const struct xb *xb, unsigned long max, unsigned long *bit);
+bool xb_find_zero(const struct xb *xb, unsigned long max, unsigned long *bit);
+
+static inline bool xb_empty(const struct xb *xb)
+{
+ return radix_tree_empty(&xb->xbrt);
+}
+
+int __must_check xb_preload(gfp_t);
+
+static inline void xb_preload_end(void)
+{
+ preempt_enable();
+}
diff --git a/lib/Makefile b/lib/Makefile
index d11c48e..08a8183 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -19,7 +19,7 @@ KCOV_INSTRUMENT_dynamic_debug.o := n
lib-y := ctype.o string.o vsprintf.o cmdline.o \
rbtree.o radix-tree.o dump_stack.o timerqueue.o\
- idr.o int_sqrt.o extable.o \
+ idr.o xbitmap.o int_sqrt.o extable.o \
sha1.o chacha20.o irq_regs.o argv_split.o \
flex_proportions.o ratelimit.o show_mem.o \
is_single_threaded.o plist.o decompress.o kobject_uevent.o \
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index c8d5556..d2bd8fe 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -37,7 +37,7 @@
#include <linux/rcupdate.h>
#include <linux/slab.h>
#include <linux/string.h>
-
+#include <linux/xbitmap.h>
/* Number of nodes in fully populated tree of given height */
static unsigned long height_to_maxnodes[RADIX_TREE_MAX_PATH + 1] __read_mostly;
@@ -77,6 +77,11 @@ static struct kmem_cache *radix_tree_node_cachep;
RADIX_TREE_MAP_SHIFT))
#define IDA_PRELOAD_SIZE (IDA_MAX_PATH * 2 - 1)
+#define XB_INDEX_BITS (BITS_PER_LONG - ilog2(IDA_BITMAP_BITS))
+#define XB_MAX_PATH (DIV_ROUND_UP(XB_INDEX_BITS, \
+ RADIX_TREE_MAP_SHIFT))
+#define XB_PRELOAD_SIZE (XB_MAX_PATH * 2 - 1)
+
/*
* Per-cpu pool of preloaded nodes
*/
@@ -1781,7 +1786,7 @@ void __rcu **radix_tree_next_chunk(const struct radix_tree_root *root,
child = rcu_dereference_raw(node->slots[offset]);
}
- if (!child)
+ if (!child && !is_idr(root))
goto restart;
if (child == RADIX_TREE_RETRY)
break;
@@ -2135,6 +2140,35 @@ int ida_pre_get(struct ida *ida, gfp_t gfp)
}
EXPORT_SYMBOL(ida_pre_get);
+/**
+ * xb_preload - preload for xb_set_bit()
+ * @gfp_mask: allocation mask to use for preloading
+ *
+ * Preallocate memory to use for the next call to xb_set_bit(). On success,
+ * return zero, with preemption disabled. On error, return -ENOMEM with
+ * preemption not disabled.
+ */
+int xb_preload(gfp_t gfp)
+{
+ if (!this_cpu_read(ida_bitmap)) {
+ struct ida_bitmap *bitmap = kmalloc(sizeof(*bitmap), gfp);
+
+ if (!bitmap)
+ return -ENOMEM;
+ /*
+ * The per-CPU variable is updated with preemption enabled.
+ * If the calling task is unlucky to be scheduled to another
+ * CPU which has no ida_bitmap allocation, it will be detected
+ * when setting a bit (i.e. xb_set_bit()).
+ */
+ bitmap = this_cpu_cmpxchg(ida_bitmap, NULL, bitmap);
+ kfree(bitmap);
+ }
+
+ return __radix_tree_preload(gfp, XB_PRELOAD_SIZE);
+}
+EXPORT_SYMBOL(xb_preload);
+
void __rcu **idr_get_free_cmn(struct radix_tree_root *root,
struct radix_tree_iter *iter, gfp_t gfp,
unsigned long max)
diff --git a/lib/xbitmap.c b/lib/xbitmap.c
new file mode 100644
index 0000000..62b2211
--- /dev/null
+++ b/lib/xbitmap.c
@@ -0,0 +1,444 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * XBitmap implementation
+ * Copyright (c) 2017 Microsoft Corporation
+ * Author: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
+ */
+
+#include <linux/bitmap.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/xbitmap.h>
+
+/**
+ * xb_set_bit() - Set a bit in the XBitmap.
+ * @xb: The XBitmap.
+ * @bit: Index of the bit to set.
+ *
+ * This function is used to set a bit in the xbitmap.
+ *
+ * Return: 0 on success. -ENOMEM if memory could not be allocated.
+ */
+int xb_set_bit(struct xb *xb, unsigned long bit)
+{
+ unsigned long index = bit / IDA_BITMAP_BITS;
+ struct radix_tree_root *root = &xb->xbrt;
+ struct radix_tree_iter iter;
+ void __rcu **slot;
+ struct ida_bitmap *bitmap;
+
+ bit %= IDA_BITMAP_BITS;
+ radix_tree_iter_init(&iter, index);
+ slot = idr_get_free_cmn(root, &iter, GFP_NOWAIT | __GFP_NOWARN, index);
+ if (IS_ERR(slot)) {
+ if (slot == ERR_PTR(-ENOSPC))
+ return 0; /* Already set */
+ return -ENOMEM;
+ }
+ bitmap = rcu_dereference_raw(*slot);
+ if (!bitmap) {
+ bitmap = this_cpu_xchg(ida_bitmap, NULL);
+ if (!bitmap)
+ return -ENOMEM;
+ memset(bitmap, 0, sizeof(*bitmap));
+ radix_tree_iter_replace(root, &iter, slot, bitmap);
+ }
+
+ __set_bit(bit, bitmap->bitmap);
+ if (bitmap_full(bitmap->bitmap, IDA_BITMAP_BITS))
+ radix_tree_iter_tag_clear(root, &iter, IDR_FREE);
+ return 0;
+}
+EXPORT_SYMBOL(xb_set_bit);
+
+/**
+ * xb_clear_bit() - Clear a bit in the XBitmap.
+ * @xb: The XBitmap.
+ * @bit: Index of the bit to clear.
+ *
+ * This function is used to clear a bit in the xbitmap.
+ */
+void xb_clear_bit(struct xb *xb, unsigned long bit)
+{
+ unsigned long index = bit / IDA_BITMAP_BITS;
+ struct radix_tree_root *root = &xb->xbrt;
+ struct radix_tree_iter iter;
+ void __rcu **slot;
+ struct ida_bitmap *bitmap;
+
+ bit %= IDA_BITMAP_BITS;
+ slot = radix_tree_iter_lookup(root, &iter, index);
+ if (!slot)
+ return;
+ bitmap = radix_tree_deref_slot(slot);
+ if (!bitmap)
+ return;
+
+ radix_tree_iter_tag_set(root, &iter, IDR_FREE);
+ __clear_bit(bit, bitmap->bitmap);
+ if (bitmap_empty(bitmap->bitmap, IDA_BITMAP_BITS)) {
+ kfree(bitmap);
+ radix_tree_iter_delete(root, &iter, slot);
+ }
+}
+EXPORT_SYMBOL(xb_clear_bit);
+
+/**
+ * xb_zero() - Clear a range of bits in the XBitmap.
+ * @xb: The XBitmap.
+ * @min: The first bit to clear.
+ * @max: The last bit to clear.
+ *
+ * This function is used to clear a range of bits in the xbitmap.
+ */
+void xb_zero(struct xb *xb, unsigned long min, unsigned long max)
+{
+ struct radix_tree_root *root = &xb->xbrt;
+ struct radix_tree_iter iter;
+ void __rcu **slot;
+ struct ida_bitmap *bitmap;
+ unsigned long index = min / IDA_BITMAP_BITS;
+ unsigned long first = min % IDA_BITMAP_BITS;
+ unsigned long maxindex = max / IDA_BITMAP_BITS;
+
+ radix_tree_for_each_slot(slot, root, &iter, index) {
+ unsigned long nbits = IDA_BITMAP_BITS;
+
+ if (index > maxindex)
+ break;
+ bitmap = radix_tree_deref_slot(slot);
+ if (!bitmap)
+ continue;
+ radix_tree_iter_tag_set(root, &iter, IDR_FREE);
+
+ if (!first && iter.index < maxindex)
+ goto delete;
+ if (iter.index == maxindex)
+ nbits = max % IDA_BITMAP_BITS + 1;
+ bitmap_clear(bitmap->bitmap, first, nbits - first);
+ first = 0;
+ if (bitmap_empty(bitmap->bitmap, IDA_BITMAP_BITS))
+ goto delete;
+ continue;
+delete:
+ kfree(bitmap);
+ radix_tree_iter_delete(root, &iter, slot);
+ }
+}
+EXPORT_SYMBOL(xb_zero);
+
+/**
+ * xb_test_bit() - Test a bit in the xbitmap.
+ * @xb: The XBitmap.
+ * @bit: Index of the bit to test.
+ *
+ * This function is used to test a bit in the xbitmap.
+ *
+ * Return: %true if the bit is set.
+ */
+bool xb_test_bit(const struct xb *xb, unsigned long bit)
+{
+ unsigned long index = bit / IDA_BITMAP_BITS;
+ struct ida_bitmap *bitmap = radix_tree_lookup(&xb->xbrt, index);
+
+ bit %= IDA_BITMAP_BITS;
+
+ if (!bitmap)
+ return false;
+ return test_bit(bit, bitmap->bitmap);
+}
+EXPORT_SYMBOL(xb_test_bit);
+
+/**
+ * xb_find_set() - Find the next set bit in a range of bits.
+ * @xb: The XBitmap.
+ * @max: The maximum position to search.
+ * @bit: The first bit to examine, and on exit, the found bit.
+ *
+ * On entry, @bit points to the index of the first bit to search. On exit,
+ * if this function returns %true, @bit will be updated to the index of the
+ * first found bit. It will not be updated if this function returns %false.
+ *
+ * Return: %true if a set bit was found.
+ */
+bool xb_find_set(const struct xb *xb, unsigned long max, unsigned long *bit)
+{
+ struct radix_tree_iter iter;
+ void __rcu **slot;
+ struct ida_bitmap *bitmap;
+ unsigned long index = *bit / IDA_BITMAP_BITS;
+ unsigned int first = *bit % IDA_BITMAP_BITS;
+ unsigned long maxindex = max / IDA_BITMAP_BITS;
+
+ radix_tree_for_each_slot(slot, &xb->xbrt, &iter, index) {
+ if (iter.index > maxindex)
+ break;
+ bitmap = radix_tree_deref_slot(slot);
+ if (bitmap) {
+ unsigned int nbits = IDA_BITMAP_BITS;
+
+ if (iter.index == maxindex)
+ nbits = max % IDA_BITMAP_BITS + 1;
+ first = find_next_bit(bitmap->bitmap, nbits, first);
+ if (first != nbits) {
+ *bit = first + iter.index * IDA_BITMAP_BITS;
+ return true;
+ }
+ }
+ first = 0;
+ }
+
+ return false;
+}
+EXPORT_SYMBOL(xb_find_set);
+
+/**
+ * xb_find_zero() - Find the next zero bit in a range of bits
+ * @xb: The XBitmap.
+ * @max: The maximum index to search.
+ * @bit: Pointer to an index.
+ *
+ * On entry, @bit points to the index of the first bit to search. On exit,
+ * if this function returns %true, @bit will be updated to the index of the
+ * first found bit. It will not be updated if this function returns %false.
+ *
+ * Return: %true if a clear bit was found.
+ */
+bool xb_find_zero(const struct xb *xb, unsigned long max, unsigned long *bit)
+{
+ void __rcu **slot;
+ struct radix_tree_iter iter;
+ struct ida_bitmap *bitmap;
+ unsigned long index = *bit / IDA_BITMAP_BITS;
+ unsigned long first = *bit % IDA_BITMAP_BITS;
+ unsigned long maxindex = max / IDA_BITMAP_BITS;
+
+ radix_tree_for_each_tagged(slot, &xb->xbrt, &iter, index, IDR_FREE) {
+ unsigned int nbits = IDA_BITMAP_BITS;
+
+ if (iter.index > maxindex)
+ return false;
+ bitmap = radix_tree_deref_slot(slot);
+ if (!bitmap)
+ break;
+ if (iter.index == maxindex)
+ nbits = max % IDA_BITMAP_BITS + 1;
+ first = find_next_zero_bit(bitmap->bitmap, nbits, first);
+ if (first != nbits)
+ break;
+ first = 0;
+ }
+
+ *bit = first + iter.index * IDA_BITMAP_BITS;
+ return true;
+}
+EXPORT_SYMBOL(xb_find_zero);
+
+#ifndef __KERNEL__
+
+static DEFINE_XB(xb1);
+
+static void xbitmap_check_bit(unsigned long bit)
+{
+ unsigned long nbit = 0;
+
+ xb_preload(GFP_KERNEL);
+ assert(!xb_test_bit(&xb1, bit));
+ assert(xb_set_bit(&xb1, bit) == 0);
+ assert(xb_test_bit(&xb1, bit));
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == true);
+ assert(nbit == bit);
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == true);
+ assert(nbit == bit);
+ nbit++;
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == false);
+ assert(nbit == bit + 1);
+ xb_clear_bit(&xb1, bit);
+ assert(xb_empty(&xb1));
+ xb_clear_bit(&xb1, bit);
+ assert(xb_empty(&xb1));
+ nbit = 0;
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == false);
+ assert(nbit == 0);
+ xb_preload_end();
+}
+
+/*
+ * In the following tests, preload is called once when all the bits to set
+ * locate in the same ida bitmap. Otherwise, it is recommended to call
+ * preload for each xb_set_bit.
+ */
+static void xbitmap_check_bit_range(void)
+{
+ unsigned long nbit = 0;
+
+ /* Regular test1: node = NULL */
+ xb_preload(GFP_KERNEL);
+ xb_set_bit(&xb1, 700);
+ xb_preload_end();
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == true);
+ assert(nbit == 700);
+ nbit++;
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == false);
+ assert(nbit == 701);
+ xb_zero(&xb1, 0, 1023);
+
+ /*
+ * Regular test2
+ * set bit 2000, 2001, 2040
+ * Next 1 in [0, 2048] --> 2000
+ * Next 1 in [2000, 2002] --> 2000
+ * Next 1 in [2002, 2040] --> 2040
+ * Next 1 in [2002, 2039] --> none
+ * Next 0 in [2000, 2048] --> 2002
+ * Next 0 in [2048, 2060] --> 2048
+ */
+ xb_preload(GFP_KERNEL);
+ assert(!xb_set_bit(&xb1, 2000));
+ assert(!xb_set_bit(&xb1, 2001));
+ assert(!xb_set_bit(&xb1, 2040));
+ nbit = 0;
+ assert(xb_find_set(&xb1, 2048, &nbit) == true);
+ assert(nbit == 2000);
+ assert(xb_find_set(&xb1, 2002, &nbit) == true);
+ assert(nbit == 2000);
+ nbit = 2002;
+ assert(xb_find_set(&xb1, 2040, &nbit) == true);
+ assert(nbit == 2040);
+ nbit = 2002;
+ assert(xb_find_set(&xb1, 2039, &nbit) == false);
+ assert(nbit == 2002);
+ nbit = 2000;
+ assert(xb_find_zero(&xb1, 2048, &nbit) == true);
+ assert(nbit == 2002);
+ nbit = 2048;
+ assert(xb_find_zero(&xb1, 2060, &nbit) == true);
+ assert(nbit == 2048);
+ xb_zero(&xb1, 0, 2048);
+ nbit = 0;
+ assert(xb_find_set(&xb1, 2048, &nbit) == false);
+ assert(nbit == 0);
+ xb_preload_end();
+
+ /*
+ * Overflow tests:
+ * Set bit 1 and ULONG_MAX - 4
+ * Next 1 in [0, ULONG_MAX] --> 1
+ * Next 1 in [1, ULONG_MAX] --> 1
+ * Next 1 in [2, ULONG_MAX] --> ULONG_MAX - 4
+ * Next 1 in [ULONG_MAX - 3, 2] --> none
+ * Next 0 in [ULONG_MAX - 4, ULONG_MAX] --> ULONG_MAX - 3
+ * Zero [ULONG_MAX - 4, ULONG_MAX]
+ * Next 1 in [ULONG_MAX - 10, ULONG_MAX] --> none
+ * Next 1 in [ULONG_MAX - 1, 2] --> none
+ * Zero [0, 1]
+ * Next 1 in [0, 2] --> none
+ */
+ xb_preload(GFP_KERNEL);
+ assert(!xb_set_bit(&xb1, 1));
+ xb_preload_end();
+ xb_preload(GFP_KERNEL);
+ assert(!xb_set_bit(&xb1, ULONG_MAX - 4));
+ nbit = 0;
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == true);
+ assert(nbit == 1);
+ nbit = 1;
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == true);
+ assert(nbit == 1);
+ nbit = 2;
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == true);
+ assert(nbit == ULONG_MAX - 4);
+ nbit++;
+ assert(xb_find_set(&xb1, 2, &nbit) == false);
+ assert(nbit == ULONG_MAX - 3);
+ nbit--;
+ assert(xb_find_zero(&xb1, ULONG_MAX, &nbit) == true);
+ assert(nbit == ULONG_MAX - 3);
+ xb_zero(&xb1, ULONG_MAX - 4, ULONG_MAX);
+ nbit = ULONG_MAX - 10;
+ assert(xb_find_set(&xb1, ULONG_MAX, &nbit) == false);
+ assert(nbit == ULONG_MAX - 10);
+ nbit = ULONG_MAX - 1;
+ assert(xb_find_set(&xb1, 2, &nbit) == false);
+ xb_zero(&xb1, 0, 1);
+ nbit = 0;
+ assert(xb_find_set(&xb1, 2, &nbit) == false);
+ assert(nbit == 0);
+ xb_preload_end();
+ assert(xb_empty(&xb1));
+}
+
+static void xbitmap_check_zero_bits(void)
+{
+ assert(xb_empty(&xb1));
+
+ /* Zero an empty xbitmap should work though no real work to do */
+ xb_zero(&xb1, 0, ULONG_MAX);
+ assert(xb_empty(&xb1));
+
+ xb_preload(GFP_KERNEL);
+ assert(xb_set_bit(&xb1, 0) == 0);
+ xb_preload_end();
+
+ /* Overflow test */
+ xb_zero(&xb1, ULONG_MAX - 10, ULONG_MAX);
+ assert(xb_test_bit(&xb1, 0));
+
+ xb_preload(GFP_KERNEL);
+ assert(xb_set_bit(&xb1, ULONG_MAX) == 0);
+ xb_preload_end();
+
+ xb_zero(&xb1, 0, ULONG_MAX);
+ assert(xb_empty(&xb1));
+}
+
+/* Check that setting an already-full bitmap works */
+static void xbitmap_check_set(unsigned long base)
+{
+ unsigned long i;
+
+ assert(xb_empty(&xb1));
+
+ for (i = 0; i < 64 * 1024; i++) {
+ xb_preload(GFP_KERNEL);
+ assert(xb_set_bit(&xb1, base + i) == 0);
+ xb_preload_end();
+ }
+ for (i = 0; i < 64 * 1024; i++)
+ assert(xb_set_bit(&xb1, base + i) == 0);
+
+ for (i = 0; i < 64 * 1024; i++)
+ xb_clear_bit(&xb1, base + i);
+
+ assert(xb_empty(&xb1));
+}
+
+static void xbitmap_checks(void)
+{
+ xb_init(&xb1);
+ xbitmap_check_bit(0);
+ xbitmap_check_bit(30);
+ xbitmap_check_bit(31);
+ xbitmap_check_bit(62);
+ xbitmap_check_bit(63);
+ xbitmap_check_bit(64);
+ xbitmap_check_bit(700);
+ xbitmap_check_bit(1023);
+ xbitmap_check_bit(1024);
+ xbitmap_check_bit(1025);
+ xbitmap_check_bit((1UL << 63) | (1UL << 24));
+ xbitmap_check_bit((1UL << 63) | (1UL << 24) | 70);
+
+ xbitmap_check_bit_range();
+ xbitmap_check_zero_bits();
+ xbitmap_check_set(0);
+ xbitmap_check_set(1024);
+ xbitmap_check_set(1024 * 64);
+}
+
+int __weak main(void)
+{
+ radix_tree_init();
+ xbitmap_checks();
+}
+#endif
diff --git a/tools/include/linux/bitmap.h b/tools/include/linux/bitmap.h
index ca16027..8d0bc1b 100644
--- a/tools/include/linux/bitmap.h
+++ b/tools/include/linux/bitmap.h
@@ -37,6 +37,40 @@ static inline void bitmap_zero(unsigned long *dst, int nbits)
}
}
+static inline void __bitmap_clear(unsigned long *map, unsigned int start,
+ int len)
+{
+ unsigned long *p = map + BIT_WORD(start);
+ const unsigned int size = start + len;
+ int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
+ unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
+
+ while (len - bits_to_clear >= 0) {
+ *p &= ~mask_to_clear;
+ len -= bits_to_clear;
+ bits_to_clear = BITS_PER_LONG;
+ mask_to_clear = ~0UL;
+ p++;
+ }
+ if (len) {
+ mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
+ *p &= ~mask_to_clear;
+ }
+}
+
+static inline __always_inline void bitmap_clear(unsigned long *map,
+ unsigned int start,
+ unsigned int nbits)
+{
+ if (__builtin_constant_p(nbits) && nbits == 1)
+ __clear_bit(start, map);
+ else if (__builtin_constant_p(start & 7) && IS_ALIGNED(start, 8) &&
+ __builtin_constant_p(nbits & 7) && IS_ALIGNED(nbits, 8))
+ memset((char *)map + start / 8, 0, nbits / 8);
+ else
+ __bitmap_clear(map, start, nbits);
+}
+
static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
{
unsigned int nlongs = BITS_TO_LONGS(nbits);
diff --git a/tools/include/linux/kernel.h b/tools/include/linux/kernel.h
index 0ad8844..3c992ae 100644
--- a/tools/include/linux/kernel.h
+++ b/tools/include/linux/kernel.h
@@ -13,6 +13,8 @@
#define UINT_MAX (~0U)
#endif
+#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
+
#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
#define PERF_ALIGN(x, a) __PERF_ALIGN_MASK(x, (typeof(x))(a)-1)
diff --git a/tools/testing/radix-tree/Makefile b/tools/testing/radix-tree/Makefile
index fa7ee36..788e526 100644
--- a/tools/testing/radix-tree/Makefile
+++ b/tools/testing/radix-tree/Makefile
@@ -1,12 +1,13 @@
# SPDX-License-Identifier: GPL-2.0
CFLAGS += -I. -I../../include -g -O2 -Wall -D_LGPL_SOURCE -fsanitize=address
-LDFLAGS += -fsanitize=address
-LDLIBS+= -lpthread -lurcu
-TARGETS = main idr-test multiorder
+LDFLAGS += -fsanitize=address $(LDLIBS)
+LDLIBS := -lpthread -lurcu
+TARGETS = main idr-test multiorder xbitmap
CORE_OFILES := radix-tree.o idr.o linux.o test.o find_bit.o
OFILES = main.o $(CORE_OFILES) regression1.o regression2.o regression3.o \
- tag_check.o multiorder.o idr-test.o iteration_check.o benchmark.o
+ tag_check.o multiorder.o idr-test.o iteration_check.o benchmark.o \
+ xbitmap.o
ifndef SHIFT
SHIFT=3
@@ -25,8 +26,10 @@ idr-test: idr-test.o $(CORE_OFILES)
multiorder: multiorder.o $(CORE_OFILES)
+xbitmap: xbitmap.o $(CORE_OFILES)
+
clean:
- $(RM) $(TARGETS) *.o radix-tree.c idr.c generated/map-shift.h
+ $(RM) $(TARGETS) *.o radix-tree.c idr.c xbitmap.c generated/map-shift.h
vpath %.c ../../lib
@@ -34,6 +37,7 @@ $(OFILES): Makefile *.h */*.h generated/map-shift.h \
../../include/linux/*.h \
../../include/asm/*.h \
../../../include/linux/radix-tree.h \
+ ../../../include/linux/xbitmap.h \
../../../include/linux/idr.h
radix-tree.c: ../../../lib/radix-tree.c
@@ -42,6 +46,9 @@ radix-tree.c: ../../../lib/radix-tree.c
idr.c: ../../../lib/idr.c
sed -e 's/^static //' -e 's/__always_inline //' -e 's/inline //' < $< > $@
+xbitmap.c: ../../../lib/xbitmap.c
+ sed -e 's/^static //' -e 's/__always_inline //' -e 's/inline //' < $< > $@
+
.PHONY: mapshift
mapshift:
diff --git a/tools/testing/radix-tree/linux/kernel.h b/tools/testing/radix-tree/linux/kernel.h
index c3bc3f3..426f32f 100644
--- a/tools/testing/radix-tree/linux/kernel.h
+++ b/tools/testing/radix-tree/linux/kernel.h
@@ -17,6 +17,4 @@
#define pr_debug printk
#define pr_cont printk
-#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
-
#endif /* _KERNEL_H */
diff --git a/tools/testing/radix-tree/linux/xbitmap.h b/tools/testing/radix-tree/linux/xbitmap.h
new file mode 100644
index 0000000..61de214
--- /dev/null
+++ b/tools/testing/radix-tree/linux/xbitmap.h
@@ -0,0 +1 @@
+#include "../../../../include/linux/xbitmap.h"
diff --git a/tools/testing/radix-tree/main.c b/tools/testing/radix-tree/main.c
index 257f3f8..d112363 100644
--- a/tools/testing/radix-tree/main.c
+++ b/tools/testing/radix-tree/main.c
@@ -326,6 +326,10 @@ static void single_thread_tests(bool long_run)
rcu_barrier();
printv(2, "after idr_checks: %d allocated, preempt %d\n",
nr_allocated, preempt_count);
+ xbitmap_checks();
+ rcu_barrier();
+ printv(2, "after xbitmap_checks: %d allocated, preempt %d\n",
+ nr_allocated, preempt_count);
big_gang_check(long_run);
rcu_barrier();
printv(2, "after big_gang_check: %d allocated, preempt %d\n",
diff --git a/tools/testing/radix-tree/test.h b/tools/testing/radix-tree/test.h
index d9c031d..8175d6b 100644
--- a/tools/testing/radix-tree/test.h
+++ b/tools/testing/radix-tree/test.h
@@ -38,6 +38,7 @@ void benchmark(void);
void idr_checks(void);
void ida_checks(void);
void ida_thread_tests(void);
+void xbitmap_checks(void);
struct item *
item_tag_set(struct radix_tree_root *root, unsigned long index, int tag);
--
2.7.4
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