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authorJens Axboe <jaxboe@fusionio.com>2011-01-24 21:53:27 +0100
committerJens Axboe <jaxboe@fusionio.com>2011-01-24 21:53:27 +0100
commit6035e7d6d1ed462176402615da37d4f987588c16 (patch)
treebbd47943549003e78181173ac14e91eae40b9ef0
parent7d130d8d2a5638ca91dc81ec085acef4d3c3ad08 (diff)
downloadfio-6035e7d6d1ed462176402615da37d4f987588c16.tar.gz
fio-6035e7d6d1ed462176402615da37d4f987588c16.tar.bz2
Remove flist_sort(), it's no longer used
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
-rw-r--r--flist_sort.h9
-rw-r--r--lib/flist_sort.c140
2 files changed, 0 insertions, 149 deletions
diff --git a/flist_sort.h b/flist_sort.h
deleted file mode 100644
index 686b7a5a..00000000
--- a/flist_sort.h
+++ /dev/null
@@ -1,9 +0,0 @@
-#ifndef FIO_FLIST_SORT_H
-#define FIO_FLIST_SORT_H
-
-struct flist_head;
-
-void flist_sort(void *priv, struct flist_head *head,
- int (*cmp)(void *priv, struct flist_head *a,
- struct flist_head *b));
-#endif
diff --git a/lib/flist_sort.c b/lib/flist_sort.c
deleted file mode 100644
index 9a2da841..00000000
--- a/lib/flist_sort.c
+++ /dev/null
@@ -1,140 +0,0 @@
-#include <string.h>
-#include <assert.h>
-
-#include "../flist.h"
-#include "../flist_sort.h"
-
-#ifndef ARRAY_SIZE
-#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
-#endif
-
-#define MAX_LIST_LENGTH_BITS 65
-
-/*
- * Returns a list organized in an intermediate format suited
- * to chaining of merge() calls: null-terminated, no reserved or
- * sentinel head node, "prev" links not maintained.
- */
-static struct flist_head *merge(void *priv,
- int (*cmp)(void *priv, struct flist_head *a,
- struct flist_head *b),
- struct flist_head *a, struct flist_head *b)
-{
- struct flist_head head, *tail = &head;
-
- while (a && b) {
- /* if equal, take 'a' -- important for sort stability */
- if ((*cmp)(priv, a, b) <= 0) {
- tail->next = a;
- a = a->next;
- } else {
- tail->next = b;
- b = b->next;
- }
- tail = tail->next;
- }
- tail->next = a?:b;
- return head.next;
-}
-
-/*
- * Combine final list merge with restoration of standard doubly-linked
- * list structure. This approach duplicates code from merge(), but
- * runs faster than the tidier alternatives of either a separate final
- * prev-link restoration pass, or maintaining the prev links
- * throughout.
- */
-static void merge_and_restore_back_links(void *priv,
- int (*cmp)(void *priv, struct flist_head *a,
- struct flist_head *b),
- struct flist_head *head,
- struct flist_head *a, struct flist_head *b)
-{
- struct flist_head *tail = head;
-
- while (a && b) {
- /* if equal, take 'a' -- important for sort stability */
- if ((*cmp)(priv, a, b) <= 0) {
- tail->next = a;
- a->prev = tail;
- a = a->next;
- } else {
- tail->next = b;
- b->prev = tail;
- b = b->next;
- }
- tail = tail->next;
- }
- tail->next = a ? : b;
-
- do {
- /*
- * In worst cases this loop may run many iterations.
- * Continue callbacks to the client even though no
- * element comparison is needed, so the client's cmp()
- * routine can invoke cond_resched() periodically.
- */
- cmp(priv, tail, tail);
-
- tail->next->prev = tail;
- tail = tail->next;
- } while (tail->next);
-
- tail->next = head;
- head->prev = tail;
-}
-
-/**
- * flist_sort - sort a list
- * @priv: private data, opaque to flist_sort(), passed to @cmp
- * @head: the list to sort
- * @cmp: the elements comparison function
- *
- * This function implements "merge sort", which has O(nlog(n))
- * complexity.
- *
- * The comparison function @cmp must return a negative value if @a
- * should sort before @b, and a positive value if @a should sort after
- * @b. If @a and @b are equivalent, and their original relative
- * ordering is to be preserved, @cmp must return 0.
- */
-void flist_sort(void *priv, struct flist_head *head,
- int (*cmp)(void *priv, struct flist_head *a,
- struct flist_head *b))
-{
- struct flist_head *part[MAX_LIST_LENGTH_BITS+1]; /* sorted partial lists
- -- last slot is a sentinel */
- int lev; /* index into part[] */
- int max_lev = 0;
- struct flist_head *list;
-
- if (flist_empty(head))
- return;
-
- memset(part, 0, sizeof(part));
-
- head->prev->next = NULL;
- list = head->next;
-
- while (list) {
- struct flist_head *cur = list;
- list = list->next;
- cur->next = NULL;
-
- for (lev = 0; part[lev]; lev++) {
- cur = merge(priv, cmp, part[lev], cur);
- part[lev] = NULL;
- }
- if (lev > max_lev) {
- assert(lev < ARRAY_SIZE(part) - 1);
- max_lev = lev;
- }
- part[lev] = cur;
- }
-
- for (lev = 0; lev < max_lev; lev++)
- if (part[lev])
- list = merge(priv, cmp, part[lev], list);
-
- merge_and_restore_back_links(priv, cmp, head, part[max_lev], list);
-}