error.o \
extents.o \
extent_update.o \
+ eytzinger.o \
fs.o \
fs-common.o \
fs-ioctl.o \
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+
+#include "eytzinger.h"
+
+/**
+ * is_aligned - is this pointer & size okay for word-wide copying?
+ * @base: pointer to data
+ * @size: size of each element
+ * @align: required alignment (typically 4 or 8)
+ *
+ * Returns true if elements can be copied using word loads and stores.
+ * The size must be a multiple of the alignment, and the base address must
+ * be if we do not have CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS.
+ *
+ * For some reason, gcc doesn't know to optimize "if (a & mask || b & mask)"
+ * to "if ((a | b) & mask)", so we do that by hand.
+ */
+__attribute_const__ __always_inline
+static bool is_aligned(const void *base, size_t size, unsigned char align)
+{
+ unsigned char lsbits = (unsigned char)size;
+
+ (void)base;
+#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
+ lsbits |= (unsigned char)(uintptr_t)base;
+#endif
+ return (lsbits & (align - 1)) == 0;
+}
+
+/**
+ * swap_words_32 - swap two elements in 32-bit chunks
+ * @a: pointer to the first element to swap
+ * @b: pointer to the second element to swap
+ * @n: element size (must be a multiple of 4)
+ *
+ * Exchange the two objects in memory. This exploits base+index addressing,
+ * which basically all CPUs have, to minimize loop overhead computations.
+ *
+ * For some reason, on x86 gcc 7.3.0 adds a redundant test of n at the
+ * bottom of the loop, even though the zero flag is still valid from the
+ * subtract (since the intervening mov instructions don't alter the flags).
+ * Gcc 8.1.0 doesn't have that problem.
+ */
+static void swap_words_32(void *a, void *b, size_t n)
+{
+ do {
+ u32 t = *(u32 *)(a + (n -= 4));
+ *(u32 *)(a + n) = *(u32 *)(b + n);
+ *(u32 *)(b + n) = t;
+ } while (n);
+}
+
+/**
+ * swap_words_64 - swap two elements in 64-bit chunks
+ * @a: pointer to the first element to swap
+ * @b: pointer to the second element to swap
+ * @n: element size (must be a multiple of 8)
+ *
+ * Exchange the two objects in memory. This exploits base+index
+ * addressing, which basically all CPUs have, to minimize loop overhead
+ * computations.
+ *
+ * We'd like to use 64-bit loads if possible. If they're not, emulating
+ * one requires base+index+4 addressing which x86 has but most other
+ * processors do not. If CONFIG_64BIT, we definitely have 64-bit loads,
+ * but it's possible to have 64-bit loads without 64-bit pointers (e.g.
+ * x32 ABI). Are there any cases the kernel needs to worry about?
+ */
+static void swap_words_64(void *a, void *b, size_t n)
+{
+ do {
+#ifdef CONFIG_64BIT
+ u64 t = *(u64 *)(a + (n -= 8));
+ *(u64 *)(a + n) = *(u64 *)(b + n);
+ *(u64 *)(b + n) = t;
+#else
+ /* Use two 32-bit transfers to avoid base+index+4 addressing */
+ u32 t = *(u32 *)(a + (n -= 4));
+ *(u32 *)(a + n) = *(u32 *)(b + n);
+ *(u32 *)(b + n) = t;
+
+ t = *(u32 *)(a + (n -= 4));
+ *(u32 *)(a + n) = *(u32 *)(b + n);
+ *(u32 *)(b + n) = t;
+#endif
+ } while (n);
+}
+
+/**
+ * swap_bytes - swap two elements a byte at a time
+ * @a: pointer to the first element to swap
+ * @b: pointer to the second element to swap
+ * @n: element size
+ *
+ * This is the fallback if alignment doesn't allow using larger chunks.
+ */
+static void swap_bytes(void *a, void *b, size_t n)
+{
+ do {
+ char t = ((char *)a)[--n];
+ ((char *)a)[n] = ((char *)b)[n];
+ ((char *)b)[n] = t;
+ } while (n);
+}
+
+/*
+ * The values are arbitrary as long as they can't be confused with
+ * a pointer, but small integers make for the smallest compare
+ * instructions.
+ */
+#define SWAP_WORDS_64 (swap_r_func_t)0
+#define SWAP_WORDS_32 (swap_r_func_t)1
+#define SWAP_BYTES (swap_r_func_t)2
+#define SWAP_WRAPPER (swap_r_func_t)3
+
+struct wrapper {
+ cmp_func_t cmp;
+ swap_func_t swap;
+};
+
+/*
+ * The function pointer is last to make tail calls most efficient if the
+ * compiler decides not to inline this function.
+ */
+static void do_swap(void *a, void *b, size_t size, swap_r_func_t swap_func, const void *priv)
+{
+ if (swap_func == SWAP_WRAPPER) {
+ ((const struct wrapper *)priv)->swap(a, b, (int)size);
+ return;
+ }
+
+ if (swap_func == SWAP_WORDS_64)
+ swap_words_64(a, b, size);
+ else if (swap_func == SWAP_WORDS_32)
+ swap_words_32(a, b, size);
+ else if (swap_func == SWAP_BYTES)
+ swap_bytes(a, b, size);
+ else
+ swap_func(a, b, (int)size, priv);
+}
+
+#define _CMP_WRAPPER ((cmp_r_func_t)0L)
+
+static int do_cmp(const void *a, const void *b, cmp_r_func_t cmp, const void *priv)
+{
+ if (cmp == _CMP_WRAPPER)
+ return ((const struct wrapper *)priv)->cmp(a, b);
+ return cmp(a, b, priv);
+}
+
+static inline int eytzinger0_do_cmp(void *base, size_t n, size_t size,
+ cmp_r_func_t cmp_func, const void *priv,
+ size_t l, size_t r)
+{
+ return do_cmp(base + inorder_to_eytzinger0(l, n) * size,
+ base + inorder_to_eytzinger0(r, n) * size,
+ cmp_func, priv);
+}
+
+static inline void eytzinger0_do_swap(void *base, size_t n, size_t size,
+ swap_r_func_t swap_func, const void *priv,
+ size_t l, size_t r)
+{
+ do_swap(base + inorder_to_eytzinger0(l, n) * size,
+ base + inorder_to_eytzinger0(r, n) * size,
+ size, swap_func, priv);
+}
+
+void eytzinger0_sort_r(void *base, size_t n, size_t size,
+ cmp_r_func_t cmp_func,
+ swap_r_func_t swap_func,
+ const void *priv)
+{
+ int i, c, r;
+
+ /* called from 'sort' without swap function, let's pick the default */
+ if (swap_func == SWAP_WRAPPER && !((struct wrapper *)priv)->swap)
+ swap_func = NULL;
+
+ if (!swap_func) {
+ if (is_aligned(base, size, 8))
+ swap_func = SWAP_WORDS_64;
+ else if (is_aligned(base, size, 4))
+ swap_func = SWAP_WORDS_32;
+ else
+ swap_func = SWAP_BYTES;
+ }
+
+ /* heapify */
+ for (i = n / 2 - 1; i >= 0; --i) {
+ for (r = i; r * 2 + 1 < n; r = c) {
+ c = r * 2 + 1;
+
+ if (c + 1 < n &&
+ eytzinger0_do_cmp(base, n, size, cmp_func, priv, c, c + 1) < 0)
+ c++;
+
+ if (eytzinger0_do_cmp(base, n, size, cmp_func, priv, r, c) >= 0)
+ break;
+
+ eytzinger0_do_swap(base, n, size, swap_func, priv, r, c);
+ }
+ }
+
+ /* sort */
+ for (i = n - 1; i > 0; --i) {
+ eytzinger0_do_swap(base, n, size, swap_func, priv, 0, i);
+
+ for (r = 0; r * 2 + 1 < i; r = c) {
+ c = r * 2 + 1;
+
+ if (c + 1 < i &&
+ eytzinger0_do_cmp(base, n, size, cmp_func, priv, c, c + 1) < 0)
+ c++;
+
+ if (eytzinger0_do_cmp(base, n, size, cmp_func, priv, r, c) >= 0)
+ break;
+
+ eytzinger0_do_swap(base, n, size, swap_func, priv, r, c);
+ }
+ }
+}
+
+void eytzinger0_sort(void *base, size_t n, size_t size,
+ cmp_func_t cmp_func,
+ swap_func_t swap_func)
+{
+ struct wrapper w = {
+ .cmp = cmp_func,
+ .swap = swap_func,
+ };
+
+ return eytzinger0_sort_r(base, n, size, _CMP_WRAPPER, SWAP_WRAPPER, &w);
+}
#include <linux/bitops.h>
#include <linux/log2.h>
-#include "util.h"
+#ifdef EYTZINGER_DEBUG
+#define EYTZINGER_BUG_ON(cond) BUG_ON(cond)
+#else
+#define EYTZINGER_BUG_ON(cond)
+#endif
/*
* Traversal for trees in eytzinger layout - a full binary tree layed out in an
- * array
- */
-
-/*
- * One based indexing version:
+ * array.
*
- * With one based indexing each level of the tree starts at a power of two -
- * good for cacheline alignment:
+ * Consider using an eytzinger tree any time you would otherwise be doing binary
+ * search over an array. Binary search is a worst case scenario for branch
+ * prediction and prefetching, but in an eytzinger tree every node's children
+ * are adjacent in memory, thus we can prefetch children before knowing the
+ * result of the comparison, assuming multiple nodes fit on a cacheline.
+ *
+ * Two variants are provided, for one based indexing and zero based indexing.
+ *
+ * Zero based indexing is more convenient, but one based indexing has better
+ * alignment and thus better performance because each new level of the tree
+ * starts at a power of two, and thus if element 0 was cacheline aligned, each
+ * new level will be as well.
*/
static inline unsigned eytzinger1_child(unsigned i, unsigned child)
{
- EBUG_ON(child > 1);
+ EYTZINGER_BUG_ON(child > 1);
return (i << 1) + child;
}
static inline unsigned eytzinger1_next(unsigned i, unsigned size)
{
- EBUG_ON(i > size);
+ EYTZINGER_BUG_ON(i > size);
if (eytzinger1_right_child(i) <= size) {
i = eytzinger1_right_child(i);
static inline unsigned eytzinger1_prev(unsigned i, unsigned size)
{
- EBUG_ON(i > size);
+ EYTZINGER_BUG_ON(i > size);
if (eytzinger1_left_child(i) <= size) {
i = eytzinger1_left_child(i) + 1;
unsigned shift = __fls(size) - b;
int s;
- EBUG_ON(!i || i > size);
+ EYTZINGER_BUG_ON(!i || i > size);
i ^= 1U << b;
i <<= 1;
unsigned shift;
int s;
- EBUG_ON(!i || i > size);
+ EYTZINGER_BUG_ON(!i || i > size);
/*
* sign bit trick:
static inline unsigned eytzinger0_child(unsigned i, unsigned child)
{
- EBUG_ON(child > 1);
+ EYTZINGER_BUG_ON(child > 1);
return (i << 1) + 1 + child;
}
(_i) != -1; \
(_i) = eytzinger0_next((_i), (_size)))
-typedef int (*eytzinger_cmp_fn)(const void *l, const void *r, size_t size);
-
/* return greatest node <= @search, or -1 if not found */
static inline ssize_t eytzinger0_find_le(void *base, size_t nr, size_t size,
- eytzinger_cmp_fn cmp, const void *search)
+ cmp_func_t cmp, const void *search)
{
unsigned i, n = 0;
do {
i = n;
- n = eytzinger0_child(i, cmp(search, base + i * size, size) >= 0);
+ n = eytzinger0_child(i, cmp(base + i * size, search) <= 0);
} while (n < nr);
if (n & 1) {
/* @i was greater than @search, return previous node: */
-
- if (i == eytzinger0_first(nr))
- return -1;
-
return eytzinger0_prev(i, nr);
} else {
return i;
}
}
+static inline ssize_t eytzinger0_find_gt(void *base, size_t nr, size_t size,
+ cmp_func_t cmp, const void *search)
+{
+ ssize_t idx = eytzinger0_find_le(base, nr, size, cmp, search);
+ return eytzinger0_next(idx, size);
+}
+
#define eytzinger0_find(base, nr, size, _cmp, search) \
({ \
void *_base = (base); \
int _res; \
\
while (_i < _nr && \
- (_res = _cmp(_search, _base + _i * _size, _size))) \
+ (_res = _cmp(_search, _base + _i * _size))) \
_i = eytzinger0_child(_i, _res > 0); \
_i; \
})
-void eytzinger0_sort(void *, size_t, size_t,
- int (*cmp_func)(const void *, const void *, size_t),
- void (*swap_func)(void *, void *, size_t));
+void eytzinger0_sort_r(void *, size_t, size_t,
+ cmp_r_func_t, swap_r_func_t, const void *);
+void eytzinger0_sort(void *, size_t, size_t, cmp_func_t, swap_func_t);
#endif /* _EYTZINGER_H */
return ret ?: bch2_blacklist_table_initialize(c);
}
-static int journal_seq_blacklist_table_cmp(const void *_l,
- const void *_r, size_t size)
+static int journal_seq_blacklist_table_cmp(const void *_l, const void *_r)
{
const struct journal_seq_blacklist_table_entry *l = _l;
const struct journal_seq_blacklist_table_entry *r = _r;
#include "replicas.h"
#include "super-io.h"
+#include <linux/sort.h>
+
static int bch2_cpu_replicas_to_sb_replicas(struct bch_fs *,
struct bch_replicas_cpu *);
/* Some (buggy!) compilers don't allow memcmp to be passed as a pointer */
-static int bch2_memcmp(const void *l, const void *r, size_t size)
+static int bch2_memcmp(const void *l, const void *r, const void *priv)
{
+ size_t size = (size_t) priv;
return memcmp(l, r, size);
}
static void bch2_cpu_replicas_sort(struct bch_replicas_cpu *r)
{
- eytzinger0_sort(r->entries, r->nr, r->entry_size, bch2_memcmp, NULL);
+ eytzinger0_sort_r(r->entries, r->nr, r->entry_size,
+ bch2_memcmp, NULL, (void *)(size_t)r->entry_size);
}
static void bch2_replicas_entry_v0_to_text(struct printbuf *out,
verify_replicas_entry(search);
-#define entry_cmp(_l, _r, size) memcmp(_l, _r, entry_size)
+#define entry_cmp(_l, _r) memcmp(_l, _r, entry_size)
idx = eytzinger0_find(r->entries, r->nr, r->entry_size,
entry_cmp, search);
#undef entry_cmp
{
unsigned i;
- sort_cmp_size(cpu_r->entries,
- cpu_r->nr,
- cpu_r->entry_size,
- bch2_memcmp, NULL);
+ sort_r(cpu_r->entries,
+ cpu_r->nr,
+ cpu_r->entry_size,
+ bch2_memcmp, NULL,
+ (void *)(size_t)cpu_r->entry_size);
for (i = 0; i < cpu_r->nr; i++) {
struct bch_replicas_entry_v1 *e =
}
}
-static int alignment_ok(const void *base, size_t align)
-{
- return IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
- ((unsigned long)base & (align - 1)) == 0;
-}
-
-static void u32_swap(void *a, void *b, size_t size)
-{
- u32 t = *(u32 *)a;
- *(u32 *)a = *(u32 *)b;
- *(u32 *)b = t;
-}
-
-static void u64_swap(void *a, void *b, size_t size)
-{
- u64 t = *(u64 *)a;
- *(u64 *)a = *(u64 *)b;
- *(u64 *)b = t;
-}
-
-static void generic_swap(void *a, void *b, size_t size)
-{
- char t;
-
- do {
- t = *(char *)a;
- *(char *)a++ = *(char *)b;
- *(char *)b++ = t;
- } while (--size > 0);
-}
-
-static inline int do_cmp(void *base, size_t n, size_t size,
- int (*cmp_func)(const void *, const void *, size_t),
- size_t l, size_t r)
-{
- return cmp_func(base + inorder_to_eytzinger0(l, n) * size,
- base + inorder_to_eytzinger0(r, n) * size,
- size);
-}
-
-static inline void do_swap(void *base, size_t n, size_t size,
- void (*swap_func)(void *, void *, size_t),
- size_t l, size_t r)
-{
- swap_func(base + inorder_to_eytzinger0(l, n) * size,
- base + inorder_to_eytzinger0(r, n) * size,
- size);
-}
-
-void eytzinger0_sort(void *base, size_t n, size_t size,
- int (*cmp_func)(const void *, const void *, size_t),
- void (*swap_func)(void *, void *, size_t))
-{
- int i, c, r;
-
- if (!swap_func) {
- if (size == 4 && alignment_ok(base, 4))
- swap_func = u32_swap;
- else if (size == 8 && alignment_ok(base, 8))
- swap_func = u64_swap;
- else
- swap_func = generic_swap;
- }
-
- /* heapify */
- for (i = n / 2 - 1; i >= 0; --i) {
- for (r = i; r * 2 + 1 < n; r = c) {
- c = r * 2 + 1;
-
- if (c + 1 < n &&
- do_cmp(base, n, size, cmp_func, c, c + 1) < 0)
- c++;
-
- if (do_cmp(base, n, size, cmp_func, r, c) >= 0)
- break;
-
- do_swap(base, n, size, swap_func, r, c);
- }
- }
-
- /* sort */
- for (i = n - 1; i > 0; --i) {
- do_swap(base, n, size, swap_func, 0, i);
-
- for (r = 0; r * 2 + 1 < i; r = c) {
- c = r * 2 + 1;
-
- if (c + 1 < i &&
- do_cmp(base, n, size, cmp_func, c, c + 1) < 0)
- c++;
-
- if (do_cmp(base, n, size, cmp_func, r, c) >= 0)
- break;
-
- do_swap(base, n, size, swap_func, r, c);
- }
- }
-}
-
-void sort_cmp_size(void *base, size_t num, size_t size,
- int (*cmp_func)(const void *, const void *, size_t),
- void (*swap_func)(void *, void *, size_t size))
-{
- /* pre-scale counters for performance */
- int i = (num/2 - 1) * size, n = num * size, c, r;
-
- if (!swap_func) {
- if (size == 4 && alignment_ok(base, 4))
- swap_func = u32_swap;
- else if (size == 8 && alignment_ok(base, 8))
- swap_func = u64_swap;
- else
- swap_func = generic_swap;
- }
-
- /* heapify */
- for ( ; i >= 0; i -= size) {
- for (r = i; r * 2 + size < n; r = c) {
- c = r * 2 + size;
- if (c < n - size &&
- cmp_func(base + c, base + c + size, size) < 0)
- c += size;
- if (cmp_func(base + r, base + c, size) >= 0)
- break;
- swap_func(base + r, base + c, size);
- }
- }
-
- /* sort */
- for (i = n - size; i > 0; i -= size) {
- swap_func(base, base + i, size);
- for (r = 0; r * 2 + size < i; r = c) {
- c = r * 2 + size;
- if (c < i - size &&
- cmp_func(base + c, base + c + size, size) < 0)
- c += size;
- if (cmp_func(base + r, base + c, size) >= 0)
- break;
- swap_func(base + r, base + c, size);
- }
- }
-}
-
#if 0
void eytzinger1_test(void)
{
memset(s + bytes, c, rem);
}
-void sort_cmp_size(void *base, size_t num, size_t size,
- int (*cmp_func)(const void *, const void *, size_t),
- void (*swap_func)(void *, void *, size_t));
-
/* just the memmove, doesn't update @_nr */
#define __array_insert_item(_array, _nr, _pos) \
memmove(&(_array)[(_pos) + 1], \
projects / linux-2.6-block.git / commitdiff