qemu-e2k/tests/test-hbitmap.c

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add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
/*
* Hierarchical bitmap unit-tests.
*
* Copyright (C) 2012 Red Hat Inc.
*
* Author: Paolo Bonzini <pbonzini@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
#include "qemu/hbitmap.h"
#include "qemu/bitmap.h"
#include "block/block.h"
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
#define LOG_BITS_PER_LONG (BITS_PER_LONG == 32 ? 5 : 6)
#define L1 BITS_PER_LONG
#define L2 (BITS_PER_LONG * L1)
#define L3 (BITS_PER_LONG * L2)
typedef struct TestHBitmapData {
HBitmap *hb;
HBitmap *meta;
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
unsigned long *bits;
size_t size;
size_t old_size;
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
int granularity;
} TestHBitmapData;
/* Check that the HBitmap and the shadow bitmap contain the same data,
* ignoring the same "first" bits.
*/
static void hbitmap_test_check(TestHBitmapData *data,
uint64_t first)
{
uint64_t count = 0;
size_t pos;
int bit;
HBitmapIter hbi;
int64_t i, next;
hbitmap_iter_init(&hbi, data->hb, first);
i = first;
for (;;) {
next = hbitmap_iter_next(&hbi);
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
if (next < 0) {
next = data->size;
}
while (i < next) {
pos = i >> LOG_BITS_PER_LONG;
bit = i & (BITS_PER_LONG - 1);
i++;
g_assert_cmpint(data->bits[pos] & (1UL << bit), ==, 0);
}
if (next == data->size) {
break;
}
pos = i >> LOG_BITS_PER_LONG;
bit = i & (BITS_PER_LONG - 1);
i++;
count++;
g_assert_cmpint(data->bits[pos] & (1UL << bit), !=, 0);
}
if (first == 0) {
g_assert_cmpint(count << data->granularity, ==, hbitmap_count(data->hb));
}
}
/* This is provided instead of a test setup function so that the sizes
are kept in the test functions (and not in main()) */
static void hbitmap_test_init(TestHBitmapData *data,
uint64_t size, int granularity)
{
size_t n;
data->hb = hbitmap_alloc(size, granularity);
n = DIV_ROUND_UP(size, BITS_PER_LONG);
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
if (n == 0) {
n = 1;
}
data->bits = g_new0(unsigned long, n);
data->size = size;
data->granularity = granularity;
if (size) {
hbitmap_test_check(data, 0);
}
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
}
static void hbitmap_test_init_meta(TestHBitmapData *data,
uint64_t size, int granularity,
int meta_chunk)
{
hbitmap_test_init(data, size, granularity);
data->meta = hbitmap_create_meta(data->hb, meta_chunk);
}
static inline size_t hbitmap_test_array_size(size_t bits)
{
size_t n = DIV_ROUND_UP(bits, BITS_PER_LONG);
return n ? n : 1;
}
static void hbitmap_test_truncate_impl(TestHBitmapData *data,
size_t size)
{
size_t n;
size_t m;
data->old_size = data->size;
data->size = size;
if (data->size == data->old_size) {
return;
}
n = hbitmap_test_array_size(size);
m = hbitmap_test_array_size(data->old_size);
data->bits = g_realloc(data->bits, sizeof(unsigned long) * n);
if (n > m) {
memset(&data->bits[m], 0x00, sizeof(unsigned long) * (n - m));
}
/* If we shrink to an uneven multiple of sizeof(unsigned long),
* scrub the leftover memory. */
if (data->size < data->old_size) {
m = size % (sizeof(unsigned long) * 8);
if (m) {
unsigned long mask = (1ULL << m) - 1;
data->bits[n-1] &= mask;
}
}
hbitmap_truncate(data->hb, size);
}
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
static void hbitmap_test_teardown(TestHBitmapData *data,
const void *unused)
{
if (data->hb) {
if (data->meta) {
hbitmap_free_meta(data->hb);
}
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
hbitmap_free(data->hb);
data->hb = NULL;
}
g_free(data->bits);
data->bits = NULL;
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
}
/* Set a range in the HBitmap and in the shadow "simple" bitmap.
* The two bitmaps are then tested against each other.
*/
static void hbitmap_test_set(TestHBitmapData *data,
uint64_t first, uint64_t count)
{
hbitmap_set(data->hb, first, count);
while (count-- != 0) {
size_t pos = first >> LOG_BITS_PER_LONG;
int bit = first & (BITS_PER_LONG - 1);
first++;
data->bits[pos] |= 1UL << bit;
}
if (data->granularity == 0) {
hbitmap_test_check(data, 0);
}
}
/* Reset a range in the HBitmap and in the shadow "simple" bitmap.
*/
static void hbitmap_test_reset(TestHBitmapData *data,
uint64_t first, uint64_t count)
{
hbitmap_reset(data->hb, first, count);
while (count-- != 0) {
size_t pos = first >> LOG_BITS_PER_LONG;
int bit = first & (BITS_PER_LONG - 1);
first++;
data->bits[pos] &= ~(1UL << bit);
}
if (data->granularity == 0) {
hbitmap_test_check(data, 0);
}
}
static void hbitmap_test_reset_all(TestHBitmapData *data)
{
size_t n;
hbitmap_reset_all(data->hb);
n = DIV_ROUND_UP(data->size, BITS_PER_LONG);
if (n == 0) {
n = 1;
}
memset(data->bits, 0, n * sizeof(unsigned long));
if (data->granularity == 0) {
hbitmap_test_check(data, 0);
}
}
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
static void hbitmap_test_check_get(TestHBitmapData *data)
{
uint64_t count = 0;
uint64_t i;
for (i = 0; i < data->size; i++) {
size_t pos = i >> LOG_BITS_PER_LONG;
int bit = i & (BITS_PER_LONG - 1);
unsigned long val = data->bits[pos] & (1UL << bit);
count += hbitmap_get(data->hb, i);
g_assert_cmpint(hbitmap_get(data->hb, i), ==, val != 0);
}
g_assert_cmpint(count, ==, hbitmap_count(data->hb));
}
static void test_hbitmap_zero(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, 0, 0);
}
static void test_hbitmap_unaligned(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L3 + 23, 0);
hbitmap_test_set(data, 0, 1);
hbitmap_test_set(data, L3 + 22, 1);
}
static void test_hbitmap_iter_empty(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L1, 0);
}
static void test_hbitmap_iter_partial(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L3, 0);
hbitmap_test_set(data, 0, L3);
hbitmap_test_check(data, 1);
hbitmap_test_check(data, L1 - 1);
hbitmap_test_check(data, L1);
hbitmap_test_check(data, L1 * 2 - 1);
hbitmap_test_check(data, L2 - 1);
hbitmap_test_check(data, L2);
hbitmap_test_check(data, L2 + 1);
hbitmap_test_check(data, L2 + L1);
hbitmap_test_check(data, L2 + L1 * 2 - 1);
hbitmap_test_check(data, L2 * 2 - 1);
hbitmap_test_check(data, L2 * 2);
hbitmap_test_check(data, L2 * 2 + 1);
hbitmap_test_check(data, L2 * 2 + L1);
hbitmap_test_check(data, L2 * 2 + L1 * 2 - 1);
hbitmap_test_check(data, L3 / 2);
}
static void test_hbitmap_set_all(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L3, 0);
hbitmap_test_set(data, 0, L3);
}
static void test_hbitmap_get_all(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L3, 0);
hbitmap_test_set(data, 0, L3);
hbitmap_test_check_get(data);
}
static void test_hbitmap_get_some(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, 2 * L2, 0);
hbitmap_test_set(data, 10, 1);
hbitmap_test_check_get(data);
hbitmap_test_set(data, L1 - 1, 1);
hbitmap_test_check_get(data);
hbitmap_test_set(data, L1, 1);
hbitmap_test_check_get(data);
hbitmap_test_set(data, L2 - 1, 1);
hbitmap_test_check_get(data);
hbitmap_test_set(data, L2, 1);
hbitmap_test_check_get(data);
}
static void test_hbitmap_set_one(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, 2 * L2, 0);
hbitmap_test_set(data, 10, 1);
hbitmap_test_set(data, L1 - 1, 1);
hbitmap_test_set(data, L1, 1);
hbitmap_test_set(data, L2 - 1, 1);
hbitmap_test_set(data, L2, 1);
}
static void test_hbitmap_set_two_elem(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, 2 * L2, 0);
hbitmap_test_set(data, L1 - 1, 2);
hbitmap_test_set(data, L1 * 2 - 1, 4);
hbitmap_test_set(data, L1 * 4, L1 + 1);
hbitmap_test_set(data, L1 * 8 - 1, L1 + 1);
hbitmap_test_set(data, L2 - 1, 2);
hbitmap_test_set(data, L2 + L1 - 1, 8);
hbitmap_test_set(data, L2 + L1 * 4, L1 + 1);
hbitmap_test_set(data, L2 + L1 * 8 - 1, L1 + 1);
}
static void test_hbitmap_set(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L3 * 2, 0);
hbitmap_test_set(data, L1 - 1, L1 + 2);
hbitmap_test_set(data, L1 * 3 - 1, L1 + 2);
hbitmap_test_set(data, L1 * 5, L1 * 2 + 1);
hbitmap_test_set(data, L1 * 8 - 1, L1 * 2 + 1);
hbitmap_test_set(data, L2 - 1, L1 + 2);
hbitmap_test_set(data, L2 + L1 * 2 - 1, L1 + 2);
hbitmap_test_set(data, L2 + L1 * 4, L1 * 2 + 1);
hbitmap_test_set(data, L2 + L1 * 7 - 1, L1 * 2 + 1);
hbitmap_test_set(data, L2 * 2 - 1, L3 * 2 - L2 * 2);
}
static void test_hbitmap_set_twice(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L1 * 3, 0);
hbitmap_test_set(data, 0, L1 * 3);
hbitmap_test_set(data, L1, 1);
}
static void test_hbitmap_set_overlap(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L3 * 2, 0);
hbitmap_test_set(data, L1 - 1, L1 + 2);
hbitmap_test_set(data, L1 * 2 - 1, L1 * 2 + 2);
hbitmap_test_set(data, 0, L1 * 3);
hbitmap_test_set(data, L1 * 8 - 1, L2);
hbitmap_test_set(data, L2, L1);
hbitmap_test_set(data, L2 - L1 - 1, L1 * 8 + 2);
hbitmap_test_set(data, L2, L3 - L2 + 1);
hbitmap_test_set(data, L3 - L1, L1 * 3);
hbitmap_test_set(data, L3 - 1, 3);
hbitmap_test_set(data, L3 - 1, L2);
}
static void test_hbitmap_reset_empty(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L3, 0);
hbitmap_test_reset(data, 0, L3);
}
static void test_hbitmap_reset(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L3 * 2, 0);
hbitmap_test_set(data, L1 - 1, L1 + 2);
hbitmap_test_reset(data, L1 * 2 - 1, L1 * 2 + 2);
hbitmap_test_set(data, 0, L1 * 3);
hbitmap_test_reset(data, L1 * 8 - 1, L2);
hbitmap_test_set(data, L2, L1);
hbitmap_test_reset(data, L2 - L1 - 1, L1 * 8 + 2);
hbitmap_test_set(data, L2, L3 - L2 + 1);
hbitmap_test_reset(data, L3 - L1, L1 * 3);
hbitmap_test_set(data, L3 - 1, 3);
hbitmap_test_reset(data, L3 - 1, L2);
hbitmap_test_set(data, 0, L3 * 2);
hbitmap_test_reset(data, 0, L1);
hbitmap_test_reset(data, 0, L2);
hbitmap_test_reset(data, L3, L3);
hbitmap_test_set(data, L3 / 2, L3);
}
static void test_hbitmap_reset_all(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_init(data, L3 * 2, 0);
hbitmap_test_set(data, L1 - 1, L1 + 2);
hbitmap_test_reset_all(data);
hbitmap_test_set(data, 0, L1 * 3);
hbitmap_test_reset_all(data);
hbitmap_test_set(data, L2, L1);
hbitmap_test_reset_all(data);
hbitmap_test_set(data, L2, L3 - L2 + 1);
hbitmap_test_reset_all(data);
hbitmap_test_set(data, L3 - 1, 3);
hbitmap_test_reset_all(data);
hbitmap_test_set(data, 0, L3 * 2);
hbitmap_test_reset_all(data);
hbitmap_test_set(data, L3 / 2, L3);
hbitmap_test_reset_all(data);
}
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
static void test_hbitmap_granularity(TestHBitmapData *data,
const void *unused)
{
/* Note that hbitmap_test_check has to be invoked manually in this test. */
hbitmap_test_init(data, L1, 1);
hbitmap_test_set(data, 0, 1);
g_assert_cmpint(hbitmap_count(data->hb), ==, 2);
hbitmap_test_check(data, 0);
hbitmap_test_set(data, 2, 1);
g_assert_cmpint(hbitmap_count(data->hb), ==, 4);
hbitmap_test_check(data, 0);
hbitmap_test_set(data, 0, 3);
g_assert_cmpint(hbitmap_count(data->hb), ==, 4);
hbitmap_test_reset(data, 0, 1);
g_assert_cmpint(hbitmap_count(data->hb), ==, 2);
}
static void test_hbitmap_iter_granularity(TestHBitmapData *data,
const void *unused)
{
HBitmapIter hbi;
/* Note that hbitmap_test_check has to be invoked manually in this test. */
hbitmap_test_init(data, 131072 << 7, 7);
hbitmap_iter_init(&hbi, data->hb, 0);
g_assert_cmpint(hbitmap_iter_next(&hbi), <, 0);
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
hbitmap_test_set(data, ((L2 + L1 + 1) << 7) + 8, 8);
hbitmap_iter_init(&hbi, data->hb, 0);
g_assert_cmpint(hbitmap_iter_next(&hbi), ==, (L2 + L1 + 1) << 7);
g_assert_cmpint(hbitmap_iter_next(&hbi), <, 0);
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
hbitmap_iter_init(&hbi, data->hb, (L2 + L1 + 2) << 7);
g_assert_cmpint(hbitmap_iter_next(&hbi), <, 0);
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
hbitmap_test_set(data, (131072 << 7) - 8, 8);
hbitmap_iter_init(&hbi, data->hb, 0);
g_assert_cmpint(hbitmap_iter_next(&hbi), ==, (L2 + L1 + 1) << 7);
g_assert_cmpint(hbitmap_iter_next(&hbi), ==, 131071 << 7);
g_assert_cmpint(hbitmap_iter_next(&hbi), <, 0);
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
hbitmap_iter_init(&hbi, data->hb, (L2 + L1 + 2) << 7);
g_assert_cmpint(hbitmap_iter_next(&hbi), ==, 131071 << 7);
g_assert_cmpint(hbitmap_iter_next(&hbi), <, 0);
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
}
static void hbitmap_test_set_boundary_bits(TestHBitmapData *data, ssize_t diff)
{
size_t size = data->size;
/* First bit */
hbitmap_test_set(data, 0, 1);
if (diff < 0) {
/* Last bit in new, shortened map */
hbitmap_test_set(data, size + diff - 1, 1);
/* First bit to be truncated away */
hbitmap_test_set(data, size + diff, 1);
}
/* Last bit */
hbitmap_test_set(data, size - 1, 1);
if (data->granularity == 0) {
hbitmap_test_check_get(data);
}
}
static void hbitmap_test_check_boundary_bits(TestHBitmapData *data)
{
size_t size = MIN(data->size, data->old_size);
if (data->granularity == 0) {
hbitmap_test_check_get(data);
hbitmap_test_check(data, 0);
} else {
/* If a granularity was set, note that every distinct
* (bit >> granularity) value that was set will increase
* the bit pop count by 2^granularity, not just 1.
*
* The hbitmap_test_check facility does not currently tolerate
* non-zero granularities, so test the boundaries and the population
* count manually.
*/
g_assert(hbitmap_get(data->hb, 0));
g_assert(hbitmap_get(data->hb, size - 1));
g_assert_cmpint(2 << data->granularity, ==, hbitmap_count(data->hb));
}
}
/* Generic truncate test. */
static void hbitmap_test_truncate(TestHBitmapData *data,
size_t size,
ssize_t diff,
int granularity)
{
hbitmap_test_init(data, size, granularity);
hbitmap_test_set_boundary_bits(data, diff);
hbitmap_test_truncate_impl(data, size + diff);
hbitmap_test_check_boundary_bits(data);
}
static void test_hbitmap_truncate_nop(TestHBitmapData *data,
const void *unused)
{
hbitmap_test_truncate(data, L2, 0, 0);
}
/**
* Grow by an amount smaller than the granularity, without crossing
* a granularity alignment boundary. Effectively a NOP.
*/
static void test_hbitmap_truncate_grow_negligible(TestHBitmapData *data,
const void *unused)
{
size_t size = L2 - 1;
size_t diff = 1;
int granularity = 1;
hbitmap_test_truncate(data, size, diff, granularity);
}
/**
* Shrink by an amount smaller than the granularity, without crossing
* a granularity alignment boundary. Effectively a NOP.
*/
static void test_hbitmap_truncate_shrink_negligible(TestHBitmapData *data,
const void *unused)
{
size_t size = L2;
ssize_t diff = -1;
int granularity = 1;
hbitmap_test_truncate(data, size, diff, granularity);
}
/**
* Grow by an amount smaller than the granularity, but crossing over
* a granularity alignment boundary.
*/
static void test_hbitmap_truncate_grow_tiny(TestHBitmapData *data,
const void *unused)
{
size_t size = L2 - 2;
ssize_t diff = 1;
int granularity = 1;
hbitmap_test_truncate(data, size, diff, granularity);
}
/**
* Shrink by an amount smaller than the granularity, but crossing over
* a granularity alignment boundary.
*/
static void test_hbitmap_truncate_shrink_tiny(TestHBitmapData *data,
const void *unused)
{
size_t size = L2 - 1;
ssize_t diff = -1;
int granularity = 1;
hbitmap_test_truncate(data, size, diff, granularity);
}
/**
* Grow by an amount smaller than sizeof(long), and not crossing over
* a sizeof(long) alignment boundary.
*/
static void test_hbitmap_truncate_grow_small(TestHBitmapData *data,
const void *unused)
{
size_t size = L2 + 1;
size_t diff = sizeof(long) / 2;
hbitmap_test_truncate(data, size, diff, 0);
}
/**
* Shrink by an amount smaller than sizeof(long), and not crossing over
* a sizeof(long) alignment boundary.
*/
static void test_hbitmap_truncate_shrink_small(TestHBitmapData *data,
const void *unused)
{
size_t size = L2;
size_t diff = sizeof(long) / 2;
hbitmap_test_truncate(data, size, -diff, 0);
}
/**
* Grow by an amount smaller than sizeof(long), while crossing over
* a sizeof(long) alignment boundary.
*/
static void test_hbitmap_truncate_grow_medium(TestHBitmapData *data,
const void *unused)
{
size_t size = L2 - 1;
size_t diff = sizeof(long) / 2;
hbitmap_test_truncate(data, size, diff, 0);
}
/**
* Shrink by an amount smaller than sizeof(long), while crossing over
* a sizeof(long) alignment boundary.
*/
static void test_hbitmap_truncate_shrink_medium(TestHBitmapData *data,
const void *unused)
{
size_t size = L2 + 1;
size_t diff = sizeof(long) / 2;
hbitmap_test_truncate(data, size, -diff, 0);
}
/**
* Grow by an amount larger than sizeof(long).
*/
static void test_hbitmap_truncate_grow_large(TestHBitmapData *data,
const void *unused)
{
size_t size = L2;
size_t diff = 8 * sizeof(long);
hbitmap_test_truncate(data, size, diff, 0);
}
/**
* Shrink by an amount larger than sizeof(long).
*/
static void test_hbitmap_truncate_shrink_large(TestHBitmapData *data,
const void *unused)
{
size_t size = L2;
size_t diff = 8 * sizeof(long);
hbitmap_test_truncate(data, size, -diff, 0);
}
static void hbitmap_check_meta(TestHBitmapData *data,
int64_t start, int count)
{
int64_t i;
for (i = 0; i < data->size; i++) {
if (i >= start && i < start + count) {
g_assert(hbitmap_get(data->meta, i));
} else {
g_assert(!hbitmap_get(data->meta, i));
}
}
}
static void hbitmap_test_meta(TestHBitmapData *data,
int64_t start, int count,
int64_t check_start, int check_count)
{
hbitmap_reset_all(data->hb);
hbitmap_reset_all(data->meta);
/* Test "unset" -> "unset" will not update meta. */
hbitmap_reset(data->hb, start, count);
hbitmap_check_meta(data, 0, 0);
/* Test "unset" -> "set" will update meta */
hbitmap_set(data->hb, start, count);
hbitmap_check_meta(data, check_start, check_count);
/* Test "set" -> "set" will not update meta */
hbitmap_reset_all(data->meta);
hbitmap_set(data->hb, start, count);
hbitmap_check_meta(data, 0, 0);
/* Test "set" -> "unset" will update meta */
hbitmap_reset_all(data->meta);
hbitmap_reset(data->hb, start, count);
hbitmap_check_meta(data, check_start, check_count);
}
static void hbitmap_test_meta_do(TestHBitmapData *data, int chunk_size)
{
uint64_t size = chunk_size * 100;
hbitmap_test_init_meta(data, size, 0, chunk_size);
hbitmap_test_meta(data, 0, 1, 0, chunk_size);
hbitmap_test_meta(data, 0, chunk_size, 0, chunk_size);
hbitmap_test_meta(data, chunk_size - 1, 1, 0, chunk_size);
hbitmap_test_meta(data, chunk_size - 1, 2, 0, chunk_size * 2);
hbitmap_test_meta(data, chunk_size - 1, chunk_size + 1, 0, chunk_size * 2);
hbitmap_test_meta(data, chunk_size - 1, chunk_size + 2, 0, chunk_size * 3);
hbitmap_test_meta(data, 7 * chunk_size - 1, chunk_size + 2,
6 * chunk_size, chunk_size * 3);
hbitmap_test_meta(data, size - 1, 1, size - chunk_size, chunk_size);
hbitmap_test_meta(data, 0, size, 0, size);
}
static void test_hbitmap_meta_byte(TestHBitmapData *data, const void *unused)
{
hbitmap_test_meta_do(data, BITS_PER_BYTE);
}
static void test_hbitmap_meta_word(TestHBitmapData *data, const void *unused)
{
hbitmap_test_meta_do(data, BITS_PER_LONG);
}
static void test_hbitmap_meta_sector(TestHBitmapData *data, const void *unused)
{
hbitmap_test_meta_do(data, BDRV_SECTOR_SIZE * BITS_PER_BYTE);
}
/**
* Create an HBitmap and test set/unset.
*/
static void test_hbitmap_meta_one(TestHBitmapData *data, const void *unused)
{
int i;
int64_t offsets[] = {
0, 1, L1 - 1, L1, L1 + 1, L2 - 1, L2, L2 + 1, L3 - 1, L3, L3 + 1
};
hbitmap_test_init_meta(data, L3 * 2, 0, 1);
for (i = 0; i < ARRAY_SIZE(offsets); i++) {
hbitmap_test_meta(data, offsets[i], 1, offsets[i], 1);
hbitmap_test_meta(data, offsets[i], L1, offsets[i], L1);
hbitmap_test_meta(data, offsets[i], L2, offsets[i], L2);
}
}
static void test_hbitmap_serialize_align(TestHBitmapData *data,
const void *unused)
{
int r;
hbitmap_test_init(data, L3 * 2, 3);
g_assert(hbitmap_is_serializable(data->hb));
r = hbitmap_serialization_align(data->hb);
g_assert_cmpint(r, ==, 64 << 3);
}
static void test_hbitmap_meta_zero(TestHBitmapData *data, const void *unused)
{
hbitmap_test_init_meta(data, 0, 0, 1);
hbitmap_check_meta(data, 0, 0);
}
static void hbitmap_test_serialize_range(TestHBitmapData *data,
uint8_t *buf, size_t buf_size,
uint64_t pos, uint64_t count)
{
size_t i;
unsigned long *el = (unsigned long *)buf;
assert(hbitmap_granularity(data->hb) == 0);
hbitmap_reset_all(data->hb);
memset(buf, 0, buf_size);
if (count) {
hbitmap_set(data->hb, pos, count);
}
g_assert(hbitmap_is_serializable(data->hb));
hbitmap_serialize_part(data->hb, buf, 0, data->size);
/* Serialized buffer is inherently LE, convert it back manually to test */
for (i = 0; i < buf_size / sizeof(unsigned long); i++) {
el[i] = (BITS_PER_LONG == 32 ? le32_to_cpu(el[i]) : le64_to_cpu(el[i]));
}
for (i = 0; i < data->size; i++) {
int is_set = test_bit(i, (unsigned long *)buf);
if (i >= pos && i < pos + count) {
g_assert(is_set);
} else {
g_assert(!is_set);
}
}
/* Re-serialize for deserialization testing */
memset(buf, 0, buf_size);
hbitmap_serialize_part(data->hb, buf, 0, data->size);
hbitmap_reset_all(data->hb);
g_assert(hbitmap_is_serializable(data->hb));
hbitmap_deserialize_part(data->hb, buf, 0, data->size, true);
for (i = 0; i < data->size; i++) {
int is_set = hbitmap_get(data->hb, i);
if (i >= pos && i < pos + count) {
g_assert(is_set);
} else {
g_assert(!is_set);
}
}
}
static void test_hbitmap_serialize_basic(TestHBitmapData *data,
const void *unused)
{
int i, j;
size_t buf_size;
uint8_t *buf;
uint64_t positions[] = { 0, 1, L1 - 1, L1, L2 - 1, L2, L2 + 1, L3 - 1 };
int num_positions = ARRAY_SIZE(positions);
hbitmap_test_init(data, L3, 0);
g_assert(hbitmap_is_serializable(data->hb));
buf_size = hbitmap_serialization_size(data->hb, 0, data->size);
buf = g_malloc0(buf_size);
for (i = 0; i < num_positions; i++) {
for (j = 0; j < num_positions; j++) {
hbitmap_test_serialize_range(data, buf, buf_size,
positions[i],
MIN(positions[j], L3 - positions[i]));
}
}
g_free(buf);
}
static void test_hbitmap_serialize_part(TestHBitmapData *data,
const void *unused)
{
int i, j, k;
size_t buf_size;
uint8_t *buf;
uint64_t positions[] = { 0, 1, L1 - 1, L1, L2 - 1, L2, L2 + 1, L3 - 1 };
int num_positions = ARRAY_SIZE(positions);
hbitmap_test_init(data, L3, 0);
buf_size = L2;
buf = g_malloc0(buf_size);
for (i = 0; i < num_positions; i++) {
hbitmap_set(data->hb, positions[i], 1);
}
g_assert(hbitmap_is_serializable(data->hb));
for (i = 0; i < data->size; i += buf_size) {
unsigned long *el = (unsigned long *)buf;
hbitmap_serialize_part(data->hb, buf, i, buf_size);
for (j = 0; j < buf_size / sizeof(unsigned long); j++) {
el[j] = (BITS_PER_LONG == 32 ? le32_to_cpu(el[j]) : le64_to_cpu(el[j]));
}
for (j = 0; j < buf_size; j++) {
bool should_set = false;
for (k = 0; k < num_positions; k++) {
if (positions[k] == j + i) {
should_set = true;
break;
}
}
g_assert_cmpint(should_set, ==, test_bit(j, (unsigned long *)buf));
}
}
g_free(buf);
}
static void test_hbitmap_serialize_zeroes(TestHBitmapData *data,
const void *unused)
{
int i;
HBitmapIter iter;
int64_t next;
uint64_t min_l1 = MAX(L1, 64);
uint64_t positions[] = { 0, min_l1, L2, L3 - min_l1};
int num_positions = ARRAY_SIZE(positions);
hbitmap_test_init(data, L3, 0);
for (i = 0; i < num_positions; i++) {
hbitmap_set(data->hb, positions[i], L1);
}
g_assert(hbitmap_is_serializable(data->hb));
for (i = 0; i < num_positions; i++) {
hbitmap_deserialize_zeroes(data->hb, positions[i], min_l1, true);
hbitmap_iter_init(&iter, data->hb, 0);
next = hbitmap_iter_next(&iter);
if (i == num_positions - 1) {
g_assert_cmpint(next, ==, -1);
} else {
g_assert_cmpint(next, ==, positions[i + 1]);
}
}
}
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
static void hbitmap_test_add(const char *testpath,
void (*test_func)(TestHBitmapData *data, const void *user_data))
{
g_test_add(testpath, TestHBitmapData, NULL, NULL, test_func,
hbitmap_test_teardown);
}
static void test_hbitmap_iter_and_reset(TestHBitmapData *data,
const void *unused)
{
HBitmapIter hbi;
hbitmap_test_init(data, L1 * 2, 0);
hbitmap_set(data->hb, 0, data->size);
hbitmap_iter_init(&hbi, data->hb, BITS_PER_LONG - 1);
hbitmap_iter_next(&hbi);
hbitmap_reset_all(data->hb);
hbitmap_iter_next(&hbi);
}
static void test_hbitmap_next_zero_check_range(TestHBitmapData *data,
uint64_t start,
uint64_t count)
{
int64_t ret1 = hbitmap_next_zero(data->hb, start, count);
int64_t ret2 = start;
int64_t end = start >= data->size || data->size - start < count ?
data->size : start + count;
for ( ; ret2 < end && hbitmap_get(data->hb, ret2); ret2++) {
;
}
if (ret2 == end) {
ret2 = -1;
}
g_assert_cmpint(ret1, ==, ret2);
}
static void test_hbitmap_next_zero_check(TestHBitmapData *data, int64_t start)
{
test_hbitmap_next_zero_check_range(data, start, UINT64_MAX);
}
static void test_hbitmap_next_zero_do(TestHBitmapData *data, int granularity)
{
hbitmap_test_init(data, L3, granularity);
test_hbitmap_next_zero_check(data, 0);
test_hbitmap_next_zero_check(data, L3 - 1);
test_hbitmap_next_zero_check_range(data, 0, 1);
test_hbitmap_next_zero_check_range(data, L3 - 1, 1);
hbitmap_set(data->hb, L2, 1);
test_hbitmap_next_zero_check(data, 0);
test_hbitmap_next_zero_check(data, L2 - 1);
test_hbitmap_next_zero_check(data, L2);
test_hbitmap_next_zero_check(data, L2 + 1);
test_hbitmap_next_zero_check_range(data, 0, 1);
test_hbitmap_next_zero_check_range(data, 0, L2);
test_hbitmap_next_zero_check_range(data, L2 - 1, 1);
test_hbitmap_next_zero_check_range(data, L2 - 1, 2);
test_hbitmap_next_zero_check_range(data, L2, 1);
test_hbitmap_next_zero_check_range(data, L2 + 1, 1);
hbitmap_set(data->hb, L2 + 5, L1);
test_hbitmap_next_zero_check(data, 0);
test_hbitmap_next_zero_check(data, L2 + 1);
test_hbitmap_next_zero_check(data, L2 + 2);
test_hbitmap_next_zero_check(data, L2 + 5);
test_hbitmap_next_zero_check(data, L2 + L1 - 1);
test_hbitmap_next_zero_check(data, L2 + L1);
test_hbitmap_next_zero_check_range(data, L2, 6);
test_hbitmap_next_zero_check_range(data, L2 + 1, 3);
test_hbitmap_next_zero_check_range(data, L2 + 4, L1);
test_hbitmap_next_zero_check_range(data, L2 + 5, L1);
hbitmap_set(data->hb, L2 * 2, L3 - L2 * 2);
test_hbitmap_next_zero_check(data, L2 * 2 - L1);
test_hbitmap_next_zero_check(data, L2 * 2 - 2);
test_hbitmap_next_zero_check(data, L2 * 2 - 1);
test_hbitmap_next_zero_check(data, L2 * 2);
test_hbitmap_next_zero_check(data, L3 - 1);
test_hbitmap_next_zero_check_range(data, L2 * 2 - L1, L1 + 1);
test_hbitmap_next_zero_check_range(data, L2 * 2, L2);
hbitmap_set(data->hb, 0, L3);
test_hbitmap_next_zero_check(data, 0);
}
static void test_hbitmap_next_zero_0(TestHBitmapData *data, const void *unused)
{
test_hbitmap_next_zero_do(data, 0);
}
static void test_hbitmap_next_zero_4(TestHBitmapData *data, const void *unused)
{
test_hbitmap_next_zero_do(data, 4);
}
static void test_hbitmap_next_dirty_area_check(TestHBitmapData *data,
uint64_t offset,
uint64_t count)
{
uint64_t off1, off2;
uint64_t len1 = 0, len2;
bool ret1, ret2;
int64_t end;
off1 = offset;
len1 = count;
ret1 = hbitmap_next_dirty_area(data->hb, &off1, &len1);
end = offset > data->size || data->size - offset < count ? data->size :
offset + count;
for (off2 = offset; off2 < end && !hbitmap_get(data->hb, off2); off2++) {
;
}
for (len2 = 1; off2 + len2 < end && hbitmap_get(data->hb, off2 + len2);
len2++) {
;
}
ret2 = off2 < end;
if (!ret2) {
/* leave unchanged */
off2 = offset;
len2 = count;
}
g_assert_cmpint(ret1, ==, ret2);
g_assert_cmpint(off1, ==, off2);
g_assert_cmpint(len1, ==, len2);
}
static void test_hbitmap_next_dirty_area_do(TestHBitmapData *data,
int granularity)
{
hbitmap_test_init(data, L3, granularity);
test_hbitmap_next_dirty_area_check(data, 0, UINT64_MAX);
test_hbitmap_next_dirty_area_check(data, 0, 1);
test_hbitmap_next_dirty_area_check(data, L3 - 1, 1);
hbitmap_set(data->hb, L2, 1);
test_hbitmap_next_dirty_area_check(data, 0, 1);
test_hbitmap_next_dirty_area_check(data, 0, L2);
test_hbitmap_next_dirty_area_check(data, 0, UINT64_MAX);
test_hbitmap_next_dirty_area_check(data, L2 - 1, UINT64_MAX);
test_hbitmap_next_dirty_area_check(data, L2 - 1, 1);
test_hbitmap_next_dirty_area_check(data, L2 - 1, 2);
test_hbitmap_next_dirty_area_check(data, L2 - 1, 3);
test_hbitmap_next_dirty_area_check(data, L2, UINT64_MAX);
test_hbitmap_next_dirty_area_check(data, L2, 1);
test_hbitmap_next_dirty_area_check(data, L2 + 1, 1);
hbitmap_set(data->hb, L2 + 5, L1);
test_hbitmap_next_dirty_area_check(data, 0, UINT64_MAX);
test_hbitmap_next_dirty_area_check(data, L2 - 2, 8);
test_hbitmap_next_dirty_area_check(data, L2 + 1, 5);
test_hbitmap_next_dirty_area_check(data, L2 + 1, 3);
test_hbitmap_next_dirty_area_check(data, L2 + 4, L1);
test_hbitmap_next_dirty_area_check(data, L2 + 5, L1);
test_hbitmap_next_dirty_area_check(data, L2 + 7, L1);
test_hbitmap_next_dirty_area_check(data, L2 + L1, L1);
test_hbitmap_next_dirty_area_check(data, L2, 0);
test_hbitmap_next_dirty_area_check(data, L2 + 1, 0);
hbitmap_set(data->hb, L2 * 2, L3 - L2 * 2);
test_hbitmap_next_dirty_area_check(data, 0, UINT64_MAX);
test_hbitmap_next_dirty_area_check(data, L2, UINT64_MAX);
test_hbitmap_next_dirty_area_check(data, L2 + 1, UINT64_MAX);
test_hbitmap_next_dirty_area_check(data, L2 + 5 + L1 - 1, UINT64_MAX);
test_hbitmap_next_dirty_area_check(data, L2 + 5 + L1, 5);
test_hbitmap_next_dirty_area_check(data, L2 * 2 - L1, L1 + 1);
test_hbitmap_next_dirty_area_check(data, L2 * 2, L2);
hbitmap_set(data->hb, 0, L3);
test_hbitmap_next_dirty_area_check(data, 0, UINT64_MAX);
}
static void test_hbitmap_next_dirty_area_0(TestHBitmapData *data,
const void *unused)
{
test_hbitmap_next_dirty_area_do(data, 0);
}
static void test_hbitmap_next_dirty_area_1(TestHBitmapData *data,
const void *unused)
{
test_hbitmap_next_dirty_area_do(data, 1);
}
static void test_hbitmap_next_dirty_area_4(TestHBitmapData *data,
const void *unused)
{
test_hbitmap_next_dirty_area_do(data, 4);
}
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
int main(int argc, char **argv)
{
g_test_init(&argc, &argv, NULL);
hbitmap_test_add("/hbitmap/size/0", test_hbitmap_zero);
hbitmap_test_add("/hbitmap/size/unaligned", test_hbitmap_unaligned);
hbitmap_test_add("/hbitmap/iter/empty", test_hbitmap_iter_empty);
hbitmap_test_add("/hbitmap/iter/partial", test_hbitmap_iter_partial);
hbitmap_test_add("/hbitmap/iter/granularity", test_hbitmap_iter_granularity);
hbitmap_test_add("/hbitmap/get/all", test_hbitmap_get_all);
hbitmap_test_add("/hbitmap/get/some", test_hbitmap_get_some);
hbitmap_test_add("/hbitmap/set/all", test_hbitmap_set_all);
hbitmap_test_add("/hbitmap/set/one", test_hbitmap_set_one);
hbitmap_test_add("/hbitmap/set/two-elem", test_hbitmap_set_two_elem);
hbitmap_test_add("/hbitmap/set/general", test_hbitmap_set);
hbitmap_test_add("/hbitmap/set/twice", test_hbitmap_set_twice);
hbitmap_test_add("/hbitmap/set/overlap", test_hbitmap_set_overlap);
hbitmap_test_add("/hbitmap/reset/empty", test_hbitmap_reset_empty);
hbitmap_test_add("/hbitmap/reset/general", test_hbitmap_reset);
hbitmap_test_add("/hbitmap/reset/all", test_hbitmap_reset_all);
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
hbitmap_test_add("/hbitmap/granularity", test_hbitmap_granularity);
hbitmap_test_add("/hbitmap/truncate/nop", test_hbitmap_truncate_nop);
hbitmap_test_add("/hbitmap/truncate/grow/negligible",
test_hbitmap_truncate_grow_negligible);
hbitmap_test_add("/hbitmap/truncate/shrink/negligible",
test_hbitmap_truncate_shrink_negligible);
hbitmap_test_add("/hbitmap/truncate/grow/tiny",
test_hbitmap_truncate_grow_tiny);
hbitmap_test_add("/hbitmap/truncate/shrink/tiny",
test_hbitmap_truncate_shrink_tiny);
hbitmap_test_add("/hbitmap/truncate/grow/small",
test_hbitmap_truncate_grow_small);
hbitmap_test_add("/hbitmap/truncate/shrink/small",
test_hbitmap_truncate_shrink_small);
hbitmap_test_add("/hbitmap/truncate/grow/medium",
test_hbitmap_truncate_grow_medium);
hbitmap_test_add("/hbitmap/truncate/shrink/medium",
test_hbitmap_truncate_shrink_medium);
hbitmap_test_add("/hbitmap/truncate/grow/large",
test_hbitmap_truncate_grow_large);
hbitmap_test_add("/hbitmap/truncate/shrink/large",
test_hbitmap_truncate_shrink_large);
hbitmap_test_add("/hbitmap/meta/zero", test_hbitmap_meta_zero);
hbitmap_test_add("/hbitmap/meta/one", test_hbitmap_meta_one);
hbitmap_test_add("/hbitmap/meta/byte", test_hbitmap_meta_byte);
hbitmap_test_add("/hbitmap/meta/word", test_hbitmap_meta_word);
hbitmap_test_add("/hbitmap/meta/sector", test_hbitmap_meta_sector);
hbitmap_test_add("/hbitmap/serialize/align",
test_hbitmap_serialize_align);
hbitmap_test_add("/hbitmap/serialize/basic",
test_hbitmap_serialize_basic);
hbitmap_test_add("/hbitmap/serialize/part",
test_hbitmap_serialize_part);
hbitmap_test_add("/hbitmap/serialize/zeroes",
test_hbitmap_serialize_zeroes);
hbitmap_test_add("/hbitmap/iter/iter_and_reset",
test_hbitmap_iter_and_reset);
hbitmap_test_add("/hbitmap/next_zero/next_zero_0",
test_hbitmap_next_zero_0);
hbitmap_test_add("/hbitmap/next_zero/next_zero_4",
test_hbitmap_next_zero_4);
hbitmap_test_add("/hbitmap/next_dirty_area/next_dirty_area_0",
test_hbitmap_next_dirty_area_0);
hbitmap_test_add("/hbitmap/next_dirty_area/next_dirty_area_1",
test_hbitmap_next_dirty_area_1);
hbitmap_test_add("/hbitmap/next_dirty_area/next_dirty_area_4",
test_hbitmap_next_dirty_area_4);
add hierarchical bitmap data type and test cases HBitmaps provides an array of bits. The bits are stored as usual in an array of unsigned longs, but HBitmap is also optimized to provide fast iteration over set bits; going from one bit to the next is O(logB n) worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough that the number of levels is in fact fixed. In order to do this, it stacks multiple bitmaps with progressively coarser granularity; in all levels except the last, bit N is set iff the N-th unsigned long is nonzero in the immediately next level. When iteration completes on the last level it can examine the 2nd-last level to quickly skip entire words, and even do so recursively to skip blocks of 64 words or powers thereof (32 on 32-bit machines). Given an index in the bitmap, it can be split in group of bits like this (for the 64-bit case): bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word So it is easy to move up simply by shifting the index right by log2(BITS_PER_LONG) bits. To move down, you shift the index left similarly, and add the word index within the group. Iteration uses ffs (find first set bit) to find the next word to examine; this operation can be done in constant time in most current architectures. Setting or clearing a range of m bits on all levels, the work to perform is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap. When iterating on a bitmap, each bit (on any level) is only visited once. Hence, The total cost of visiting a bitmap with m bits in it is the number of bits that are set in all bitmaps. Unless the bitmap is extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized cost of advancing from one bit to the next is usually constant. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-01-21 17:09:40 +01:00
g_test_run();
return 0;
}