change chunk_pool from list to pool

7 files changed, 89 insertions, 722 deletions

diff --git a/src/list.h b/src/list.h
deleted file mode 100644
index 20ce307..0000000
--- a/src/list.h
+++ /dev/null
@@ -1,573 +0,0 @@
-/**
- * 
- * I grub it from linux kernel source code and fix it for user space
- * program. Of course, this is a GPL licensed header file.
- *
- * Here is a recipe to cook list.h for user space program
- *
- * 1. copy list.h from linux/include/list.h
- * 2. remove 
- *     - #ifdef __KERNE__ and its #endif
- *     - all #include line
- *     - prefetch() and rcu related functions
- * 3. add macro offsetof() and container_of
- *
- * - kazutomo@mcs.anl.gov
- */
-#ifndef _LINUX_LIST_H
-#define _LINUX_LIST_H
-
-/**
- * @name from other kernel headers
- */
-/*@{*/
-
-/**
- * Get offset of a member
- */
-#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
-
-/**
- * Casts a member of a structure out to the containing structure
- * @param ptr        the pointer to the member.
- * @param type       the type of the container struct this is embedded in.
- * @param member     the name of the member within the struct.
- *
- */
-#define container_of(ptr, type, member) ({                      \
-        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
-        (type *)( (char *)__mptr - offsetof(type,member) );})
-/*@}*/
-
-
-/*
- * These are non-NULL pointers that will result in page faults
- * under normal circumstances, used to verify that nobody uses
- * non-initialized list entries.
- */
-#define LIST_POISON1  ((void *) 0x00100100)
-#define LIST_POISON2  ((void *) 0x00200200)
-
-/**
- * Simple doubly linked list implementation.
- *
- * Some of the internal functions ("__xxx") are useful when
- * manipulating whole lists rather than single entries, as
- * sometimes we already know the next/prev entries and we can
- * generate better code by using them directly rather than
- * using the generic single-entry routines.
- */
-struct list_head {
-	struct list_head *next, *prev;
-};
-
-#define LIST_HEAD_INIT(name) { &(name), &(name) }
-
-#define LIST_HEAD(name) \
-	struct list_head name = LIST_HEAD_INIT(name)
-
-#define INIT_LIST_HEAD(ptr) do { \
-	(ptr)->next = (ptr); (ptr)->prev = (ptr); \
-} while (0)
-
-/*
- * Insert a new entry between two known consecutive entries.
- *
- * This is only for internal list manipulation where we know
- * the prev/next entries already!
- */
-static inline void __list_add(struct list_head *new,
-			      struct list_head *prev,
-			      struct list_head *next)
-{
-	next->prev = new;
-	new->next = next;
-	new->prev = prev;
-	prev->next = new;
-}
-
-/**
- * list_add - add a new entry
- * @new: new entry to be added
- * @head: list head to add it after
- *
- * Insert a new entry after the specified head.
- * This is good for implementing stacks.
- */
-static inline void list_add(struct list_head *new, struct list_head *head)
-{
-	__list_add(new, head, head->next);
-}
-
-/**
- * list_add_tail - add a new entry
- * @new: new entry to be added
- * @head: list head to add it before
- *
- * Insert a new entry before the specified head.
- * This is useful for implementing queues.
- */
-static inline void list_add_tail(struct list_head *new, struct list_head *head)
-{
-	__list_add(new, head->prev, head);
-}
-
-
-/*
- * Delete a list entry by making the prev/next entries
- * point to each other.
- *
- * This is only for internal list manipulation where we know
- * the prev/next entries already!
- */
-static inline void __list_del(struct list_head * prev, struct list_head * next)
-{
-	next->prev = prev;
-	prev->next = next;
-}
-
-/**
- * list_del - deletes entry from list.
- * @entry: the element to delete from the list.
- * Note: list_empty on entry does not return true after this, the entry is
- * in an undefined state.
- */
-static inline void list_del(struct list_head *entry)
-{
-	__list_del(entry->prev, entry->next);
-	entry->next = LIST_POISON1;
-	entry->prev = LIST_POISON2;
-}
-
-
-
-/**
- * list_del_init - deletes entry from list and reinitialize it.
- * @entry: the element to delete from the list.
- */
-static inline void list_del_init(struct list_head *entry)
-{
-	__list_del(entry->prev, entry->next);
-	INIT_LIST_HEAD(entry);
-}
-
-/**
- * list_move - delete from one list and add as another's head
- * @list: the entry to move
- * @head: the head that will precede our entry
- */
-static inline void list_move(struct list_head *list, struct list_head *head)
-{
-        __list_del(list->prev, list->next);
-        list_add(list, head);
-}
-
-/**
- * list_move_tail - delete from one list and add as another's tail
- * @list: the entry to move
- * @head: the head that will follow our entry
- */
-static inline void list_move_tail(struct list_head *list,
-				  struct list_head *head)
-{
-        __list_del(list->prev, list->next);
-        list_add_tail(list, head);
-}
-
-/**
- * list_empty - tests whether a list is empty
- * @head: the list to test.
- */
-static inline int list_empty(const struct list_head *head)
-{
-	return head->next == head;
-}
-
-static inline void __list_splice(struct list_head *list,
-				 struct list_head *head)
-{
-	struct list_head *first = list->next;
-	struct list_head *last = list->prev;
-	struct list_head *at = head->next;
-
-	first->prev = head;
-	head->next = first;
-
-	last->next = at;
-	at->prev = last;
-}
-
-/**
- * list_splice - join two lists
- * @list: the new list to add.
- * @head: the place to add it in the first list.
- */
-static inline void list_splice(struct list_head *list, struct list_head *head)
-{
-	if (!list_empty(list))
-		__list_splice(list, head);
-}
-
-static inline void __list_splice_tail(struct list_head *list,
-				      struct list_head *head)
-{
-	struct list_head *first = list->next;
-	struct list_head *last = list->prev;
-	struct list_head *at = head->prev;
-
-	first->prev = at;
-	at->next = first;
-
-	last->next = head;
-	at->prev = last;
-}
-
-/**
- * list_splice_tail - join two lists
- * @list: the new list to add.
- * @head: the place to add it in the first list.
- */
-static inline void list_splice_tail(struct list_head *list, struct list_head *head)
-{
-	if (!list_empty(list))
-		__list_splice_tail(list, head);
-}
-
-
-/**
- * list_splice_init - join two lists and reinitialise the emptied list.
- * @list: the new list to add.
- * @head: the place to add it in the first list.
- *
- * The list at @list is reinitialised
- */
-static inline void list_splice_init(struct list_head *list,
-				    struct list_head *head)
-{
-	if (!list_empty(list)) {
-		__list_splice(list, head);
-		INIT_LIST_HEAD(list);
-	}
-}
-
-/**
- * list_entry - get the struct for this entry
- * @ptr:	the &struct list_head pointer.
- * @type:	the type of the struct this is embedded in.
- * @member:	the name of the list_struct within the struct.
- */
-#define list_entry(ptr, type, member) \
-	container_of(ptr, type, member)
-
-/**
- * list_for_each	-	iterate over a list
- * @pos:	the &struct list_head to use as a loop counter.
- * @head:	the head for your list.
- */
-
-#define list_for_each(pos, head) \
-  for (pos = (head)->next; pos != (head);	\
-       pos = pos->next)
-
-/**
- * __list_for_each	-	iterate over a list
- * @pos:	the &struct list_head to use as a loop counter.
- * @head:	the head for your list.
- *
- * This variant differs from list_for_each() in that it's the
- * simplest possible list iteration code, no prefetching is done.
- * Use this for code that knows the list to be very short (empty
- * or 1 entry) most of the time.
- */
-#define __list_for_each(pos, head) \
-	for (pos = (head)->next; pos != (head); pos = pos->next)
-
-/**
- * list_for_each_prev	-	iterate over a list backwards
- * @pos:	the &struct list_head to use as a loop counter.
- * @head:	the head for your list.
- */
-#define list_for_each_prev(pos, head) \
-	for (pos = (head)->prev; prefetch(pos->prev), pos != (head); \
-        	pos = pos->prev)
-
-/**
- * list_for_each_safe	-	iterate over a list safe against removal of list entry
- * @pos:	the &struct list_head to use as a loop counter.
- * @n:		another &struct list_head to use as temporary storage
- * @head:	the head for your list.
- */
-#define list_for_each_safe(pos, n, head) \
-	for (pos = (head)->next, n = pos->next; pos != (head); \
-		pos = n, n = pos->next)
-
-/**
- * list_for_each_entry	-	iterate over list of given type
- * @pos:	the type * to use as a loop counter.
- * @head:	the head for your list.
- * @member:	the name of the list_struct within the struct.
- */
-#define list_for_each_entry(pos, head, member)				\
-	for (pos = list_entry((head)->next, typeof(*pos), member);	\
-	     &pos->member != (head);					\
-	     pos = list_entry(pos->member.next, typeof(*pos), member))
-
-/**
- * list_for_each_entry_reverse - iterate backwards over list of given type.
- * @pos:	the type * to use as a loop counter.
- * @head:	the head for your list.
- * @member:	the name of the list_struct within the struct.
- */
-#define list_for_each_entry_reverse(pos, head, member)			\
-	for (pos = list_entry((head)->prev, typeof(*pos), member);	\
-	     &pos->member != (head); 	\
-	     pos = list_entry(pos->member.prev, typeof(*pos), member))
-
-/**
- * list_prepare_entry - prepare a pos entry for use as a start point in
- *			list_for_each_entry_continue
- * @pos:	the type * to use as a start point
- * @head:	the head of the list
- * @member:	the name of the list_struct within the struct.
- */
-#define list_prepare_entry(pos, head, member) \
-	((pos) ? : list_entry(head, typeof(*pos), member))
-
-/**
- * list_for_each_entry_continue -	iterate over list of given type
- *			continuing after existing point
- * @pos:	the type * to use as a loop counter.
- * @head:	the head for your list.
- * @member:	the name of the list_struct within the struct.
- */
-#define list_for_each_entry_continue(pos, head, member) 		\
-	for (pos = list_entry(pos->member.next, typeof(*pos), member);	\
-	     &pos->member != (head);	\
-	     pos = list_entry(pos->member.next, typeof(*pos), member))
-
-/**
- * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
- * @pos:	the type * to use as a loop counter.
- * @n:		another type * to use as temporary storage
- * @head:	the head for your list.
- * @member:	the name of the list_struct within the struct.
- */
-#define list_for_each_entry_safe(pos, n, head, member)			\
-	for (pos = list_entry((head)->next, typeof(*pos), member),	\
-		n = list_entry(pos->member.next, typeof(*pos), member);	\
-	     &pos->member != (head); 					\
-	     pos = n, n = list_entry(n->member.next, typeof(*n), member))
-
-/**
- * list_for_each_entry_safe_continue -	iterate over list of given type
- *			continuing after existing point safe against removal of list entry
- * @pos:	the type * to use as a loop counter.
- * @n:		another type * to use as temporary storage
- * @head:	the head for your list.
- * @member:	the name of the list_struct within the struct.
- */
-#define list_for_each_entry_safe_continue(pos, n, head, member) 		\
-	for (pos = list_entry(pos->member.next, typeof(*pos), member), 		\
-		n = list_entry(pos->member.next, typeof(*pos), member);		\
-	     &pos->member != (head);						\
-	     pos = n, n = list_entry(n->member.next, typeof(*n), member))
-
-/**
- * list_for_each_entry_safe_reverse - iterate backwards over list of given type safe against
- *				      removal of list entry
- * @pos:	the type * to use as a loop counter.
- * @n:		another type * to use as temporary storage
- * @head:	the head for your list.
- * @member:	the name of the list_struct within the struct.
- */
-#define list_for_each_entry_safe_reverse(pos, n, head, member)		\
-	for (pos = list_entry((head)->prev, typeof(*pos), member),	\
-		n = list_entry(pos->member.prev, typeof(*pos), member);	\
-	     &pos->member != (head); 					\
-	     pos = n, n = list_entry(n->member.prev, typeof(*n), member))
-
-
-
-
-/*
- * Double linked lists with a single pointer list head.
- * Mostly useful for hash tables where the two pointer list head is
- * too wasteful.
- * You lose the ability to access the tail in O(1).
- */
-
-struct hlist_head {
-	struct hlist_node *first;
-};
-
-struct hlist_node {
-	struct hlist_node *next, **pprev;
-};
-
-#define HLIST_HEAD_INIT { .first = NULL }
-#define HLIST_HEAD(name) struct hlist_head name = {  .first = NULL }
-#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL)
-#define INIT_HLIST_NODE(ptr) ((ptr)->next = NULL, (ptr)->pprev = NULL)
-
-static inline int hlist_unhashed(const struct hlist_node *h)
-{
-	return !h->pprev;
-}
-
-static inline int hlist_empty(const struct hlist_head *h)
-{
-	return !h->first;
-}
-
-static inline void __hlist_del(struct hlist_node *n)
-{
-	struct hlist_node *next = n->next;
-	struct hlist_node **pprev = n->pprev;
-	*pprev = next;
-	if (next)
-		next->pprev = pprev;
-}
-
-static inline void hlist_del(struct hlist_node *n)
-{
-	__hlist_del(n);
-	n->next = LIST_POISON1;
-	n->pprev = LIST_POISON2;
-}
-
-
-static inline void hlist_del_init(struct hlist_node *n)
-{
-	if (n->pprev)  {
-		__hlist_del(n);
-		INIT_HLIST_NODE(n);
-	}
-}
-
-static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
-{
-	struct hlist_node *first = h->first;
-	n->next = first;
-	if (first)
-		first->pprev = &n->next;
-	h->first = n;
-	n->pprev = &h->first;
-}
-
-
-
-/* next must be != NULL */
-static inline void hlist_add_before(struct hlist_node *n,
-					struct hlist_node *next)
-{
-	n->pprev = next->pprev;
-	n->next = next;
-	next->pprev = &n->next;
-	*(n->pprev) = n;
-}
-
-static inline void hlist_add_after(struct hlist_node *n,
-					struct hlist_node *next)
-{
-	next->next = n->next;
-	n->next = next;
-	next->pprev = &n->next;
-
-	if(next->next)
-		next->next->pprev  = &next->next;
-}
-
-
-
-#define hlist_entry(ptr, type, member) container_of(ptr,type,member)
-
-#define hlist_for_each(pos, head) \
-	for (pos = (head)->first; pos && ({ prefetch(pos->next); 1; }); \
-	     pos = pos->next)
-
-#define hlist_for_each_safe(pos, n, head) \
-	for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \
-	     pos = n)
-
-/**
- * hlist_for_each_entry	- iterate over list of given type
- * @tpos:	the type * to use as a loop counter.
- * @pos:	the &struct hlist_node to use as a loop counter.
- * @head:	the head for your list.
- * @member:	the name of the hlist_node within the struct.
- */
-#define hlist_for_each_entry(tpos, pos, head, member)			 \
-	for (pos = (head)->first;					 \
-	     pos && ({ prefetch(pos->next); 1;}) &&			 \
-		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
-	     pos = pos->next)
-
-/**
- * hlist_for_each_entry_continue - iterate over a hlist continuing after existing point
- * @tpos:	the type * to use as a loop counter.
- * @pos:	the &struct hlist_node to use as a loop counter.
- * @member:	the name of the hlist_node within the struct.
- */
-#define hlist_for_each_entry_continue(tpos, pos, member)		 \
-	for (pos = (pos)->next;						 \
-	     pos && ({ prefetch(pos->next); 1;}) &&			 \
-		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
-	     pos = pos->next)
-
-/**
- * hlist_for_each_entry_from - iterate over a hlist continuing from existing point
- * @tpos:	the type * to use as a loop counter.
- * @pos:	the &struct hlist_node to use as a loop counter.
- * @member:	the name of the hlist_node within the struct.
- */
-#define hlist_for_each_entry_from(tpos, pos, member)			 \
-	for (; pos && ({ prefetch(pos->next); 1;}) &&			 \
-		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
-	     pos = pos->next)
-
-/**
- * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry
- * @tpos:	the type * to use as a loop counter.
- * @pos:	the &struct hlist_node to use as a loop counter.
- * @n:		another &struct hlist_node to use as temporary storage
- * @head:	the head for your list.
- * @member:	the name of the hlist_node within the struct.
- */
-#define hlist_for_each_entry_safe(tpos, pos, n, head, member) 		 \
-	for (pos = (head)->first;					 \
-	     pos && ({ n = pos->next; 1; }) && 				 \
-		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
-	     pos = n)
-
-
-/**
- * list_count - return length of list
- * @head        the head for your list.
- */
-static inline int list_count(struct list_head *head)
-{
-	int n = 0;
-	struct list_head *p;
-
-	list_for_each(p, head) n++;
-	return n;
-}
-
-
-/**
- * list_free_f - free items in a list with a function
- * @head	the heaf for your list.
- * @f           function that releases an item in the list.
- */
-static inline void list_free_f(struct list_head *head, void (*f)(struct list_head *))
-{
-	struct list_head *p, *n;
-
-        list_for_each_safe(p, n, head) {
-                list_del(p);
-                f(p);
-        }
-}
-
-#endif
-
diff --git a/src/mscp.c b/src/mscp.c
index 8897e2a..1bbdb8e 100644
--- a/src/mscp.c
+++ b/src/mscp.c
@@ -6,7 +6,6 @@
 #include <semaphore.h>
 #include <sys/time.h>
 
-#include <list.h>
 #include <pool.h>
 #include <minmax.h>
 #include <ssh.h>
@@ -34,6 +33,7 @@ struct mscp_thread {
 
 	/* attributes used by scan thread */
 	size_t total_bytes;
+	bool finished;
 };
 
 struct mscp {
@@ -50,14 +50,15 @@ struct mscp {
 	sftp_session first; /* first sftp session */
 
 	char dst_path[PATH_MAX];
-	pool *src_pool, *path_pool;
-	pool *thread_pool; /* mscp_threads for copy thread */
 
-	struct chunk_pool cp;
+	pool *src_pool, *path_pool, *chunk_pool, *thread_pool;
 
 	struct mscp_thread scan; /* mscp_thread for mscp_scan_thread() */
+#define mscp_scan_is_finished(m) ((m)->scan.finished)
 };
 
+
+
 #define DEFAULT_MIN_CHUNK_SZ (64 << 20) /* 64MB */
 #define DEFAULT_NR_AHEAD 32
 #define DEFAULT_BUF_SZ 16384
@@ -223,29 +224,28 @@ struct mscp *mscp_init(const char *remote_host, int direction, struct mscp_opts
 		return NULL;
 	}
 
-	m = malloc(sizeof(*m));
-	if (!m) {
+	if (!(m = malloc(sizeof(*m)))) {
 		priv_set_errv("malloc: %s", strerrno());
 		return NULL;
 	}
 	memset(m, 0, sizeof(*m));
 
-	m->src_pool = pool_new();
-	if (!m->src_pool) {
+	if (!(m->src_pool = pool_new())) {
 		priv_set_errv("pool_new: %s", strerrno());
 		goto free_out;
 	}
 
-	m->path_pool = pool_new();
-	if (!m->path_pool) {
+	if (!(m->path_pool = pool_new())) {
 		priv_set_errv("pool_new: %s", strerrno());
 		goto free_out;
 	}
 
-	chunk_pool_init(&m->cp);
+	if (!(m->chunk_pool = pool_new())) {
+		priv_set_errv("pool_new: %s", strerrno());
+		goto free_out;
+	}
 
-	m->thread_pool = pool_new();
-	if (!m->thread_pool) {
+	if (!(m->thread_pool = pool_new())) {
 		priv_set_errv("pool_new: %s", strerrno());
 		goto free_out;
 	}
@@ -255,8 +255,7 @@ struct mscp *mscp_init(const char *remote_host, int direction, struct mscp_opts
 		goto free_out;
 	}
 
-	m->remote = strdup(remote_host);
-	if (!m->remote) {
+	if (!(m->remote = strdup(remote_host))) {
 		priv_set_errv("strdup: %s", strerrno());
 		goto free_out;
 	}
@@ -285,8 +284,12 @@ free_out:
 		pool_free(m->src_pool);
 	if (m->path_pool)
 		pool_free(m->path_pool);
+	if (m->chunk_pool)
+		pool_free(m->chunk_pool);
 	if (m->thread_pool)
 		pool_free(m->thread_pool);
+	if (m->remote)
+		free(m->remote);
 	free(m);
 	return NULL;
 }
@@ -405,8 +408,8 @@ void *mscp_scan_thread(void *arg)
 			a.dst_path_is_dir = true;
 	}
 
-	a.cp = &m->cp;
 	a.path_pool = m->path_pool;
+	a.chunk_pool = m->chunk_pool;
 	a.nr_conn = m->opts->nr_threads;
 	a.min_chunk_sz = m->opts->min_chunk_sz;
 	a.max_chunk_sz = m->opts->max_chunk_sz;
@@ -443,13 +446,13 @@ void *mscp_scan_thread(void *arg)
 	}
 
 	pr_info("walk source path(s) done");
-	chunk_pool_set_filled(&m->cp);
 	t->ret = 0;
+	t->finished = true;
 	return NULL;
 
 err_out:
-	chunk_pool_set_filled(&m->cp);
 	t->ret = -1;
+	t->finished = true;
 	return NULL;
 }
 
@@ -461,6 +464,7 @@ int mscp_scan(struct mscp *m)
 	memset(t, 0, sizeof(*t));
 	t->m = m;
 	t->sftp = m->first;
+	t->finished = false;
 
 	ret = pthread_create(&t->tid, NULL, mscp_scan_thread, t);
 	if (ret < 0) {
@@ -473,8 +477,8 @@ int mscp_scan(struct mscp *m)
 	 * finished. If the number of chunks are smaller than
 	 * nr_threads, we adjust nr_threads to the number of chunks.
 	 */
-	while (!chunk_pool_is_filled(&m->cp) &&
-	       chunk_pool_size(&m->cp) < m->opts->nr_threads)
+	while (!mscp_scan_is_finished(m) &&
+	       pool_size(m->chunk_pool) < m->opts->nr_threads)
 		usleep(100);
 
 	return 0;
@@ -527,7 +531,7 @@ int mscp_start(struct mscp *m)
 	struct mscp_thread *t;
 	int n, ret = 0;
 
-	if ((n = chunk_pool_size(&m->cp)) < m->opts->nr_threads) {
+	if ((n = pool_size(m->chunk_pool)) < m->opts->nr_threads) {
 		pr_notice("we have %d chunk(s), set number of connections to %d", n, n);
 		m->opts->nr_threads = n;
 	}
@@ -613,7 +617,7 @@ void *mscp_copy_thread(void *arg)
 	struct mscp_thread *t = arg;
 	struct mscp *m = t->m;
 	struct chunk *c;
-	bool nomore;
+	bool next_chunk_exist;
 
 	/* when error occurs, each thread prints error messages
 	 * immediately with pr_* functions. */
@@ -631,7 +635,7 @@ void *mscp_copy_thread(void *arg)
 		goto err_out;
 	}
 
-	if (!(nomore = chunk_pool_is_empty(&m->cp))) {
+	if ((next_chunk_exist = pool_iter_check_next_lock(m->chunk_pool))) {
 		if (m->opts->interval > 0)
 			wait_for_interval(m->opts->interval);
 		pr_notice("thread[%d]: connecting to %s", t->id, m->remote);
@@ -643,7 +647,7 @@ void *mscp_copy_thread(void *arg)
 		goto err_out;
 	}
 
-	if (nomore) {
+	if (!next_chunk_exist) {
 		pr_notice("thread[%d]: no more connections needed", t->id);
 		goto out;
 	}
@@ -668,15 +672,17 @@ void *mscp_copy_thread(void *arg)
 	}
 
 	while (1) {
-		c = chunk_pool_pop(&m->cp);
-		if (c == CHUNK_POP_WAIT) {
-			usleep(100); /* XXX: hard code */
-			continue;
+		c = pool_iter_next_lock(m->chunk_pool);
+		if (c == NULL) {
+			if (!mscp_scan_is_finished(m)) {
+				/* scan is not finished, wait. */
+				usleep(100);
+				continue;
+			}
+			/* scan is finished, and no more chunks */
+			break;
 		}
 
-		if (!c)
-			break; /* no more chunks */
-
 		if ((t->ret = copy_chunk(c, src_sftp, dst_sftp, m->opts->nr_ahead,
 					 m->opts->buf_sz, m->opts->preserve_ts,
 					 &t->copied_bytes)) < 0)
@@ -710,10 +716,7 @@ void mscp_cleanup(struct mscp *m)
 
 	pool_zeroize(m->src_pool, free);
 	pool_zeroize(m->path_pool, (pool_map_f)free_path);
-
-	chunk_pool_release(&m->cp);
-	chunk_pool_init(&m->cp);
-
+	pool_zeroize(m->chunk_pool, free);
 	pool_zeroize(m->thread_pool, free);
 }
 
diff --git a/src/path.c b/src/path.c
index d745ec7..55fa83b 100644
--- a/src/path.c
+++ b/src/path.c
@@ -14,84 +14,6 @@
 #include <strerrno.h>
 #include <print.h>
 
-/* chunk pool operations */
-#define CHUNK_POOL_STATE_FILLING 0
-#define CHUNK_POOL_STATE_FILLED 1
-
-void chunk_pool_init(struct chunk_pool *cp)
-{
-	memset(cp, 0, sizeof(*cp));
-	INIT_LIST_HEAD(&cp->list);
-	lock_init(&cp->lock);
-	cp->state = CHUNK_POOL_STATE_FILLING;
-}
-
-static void chunk_pool_add(struct chunk_pool *cp, struct chunk *c)
-{
-	LOCK_ACQUIRE(&cp->lock);
-	list_add_tail(&c->list, &cp->list);
-	cp->count += 1;
-	LOCK_RELEASE();
-}
-
-void chunk_pool_set_filled(struct chunk_pool *cp)
-{
-	cp->state = CHUNK_POOL_STATE_FILLED;
-}
-
-bool chunk_pool_is_filled(struct chunk_pool *cp)
-{
-	return (cp->state == CHUNK_POOL_STATE_FILLED);
-}
-
-size_t chunk_pool_size(struct chunk_pool *cp)
-{
-	return cp->count;
-}
-
-bool chunk_pool_is_empty(struct chunk_pool *cp)
-{
-	return list_empty(&cp->list);
-}
-
-struct chunk *chunk_pool_pop(struct chunk_pool *cp)
-{
-	struct list_head *first;
-	struct chunk *c = NULL;
-
-	LOCK_ACQUIRE(&cp->lock);
-	first = cp->list.next;
-	if (list_empty(&cp->list)) {
-		if (!chunk_pool_is_filled(cp))
-			c = CHUNK_POP_WAIT;
-		else
-			c = NULL; /* no more chunks */
-	} else {
-		c = list_entry(first, struct chunk, list);
-		list_del(first);
-	}
-	LOCK_RELEASE();
-
-	/* return CHUNK_POP_WAIT would be a rare case, because it
-	 * means copying over SSH is faster than traversing
-	 * local/remote file paths.
-	 */
-
-	return c;
-}
-
-static void chunk_free(struct list_head *list)
-{
-	struct chunk *c;
-	c = list_entry(list, typeof(*c), list);
-	free(c);
-}
-
-void chunk_pool_release(struct chunk_pool *cp)
-{
-	list_free_f(&cp->list, chunk_free);
-}
-
 /* paths of copy source resoltion */
 static char *resolve_dst_path(const char *src_file_path, struct path_resolve_args *a)
 {
@@ -169,6 +91,7 @@ static struct chunk *alloc_chunk(struct path *p)
 	c->p = p;
 	c->off = 0;
 	c->len = 0;
+	c->state = CHUNK_STATE_INIT;
 	refcnt_inc(&p->refcnt);
 	return c;
 }
@@ -202,7 +125,10 @@ static int resolve_chunk(struct path *p, struct path_resolve_args *a)
 		c->off = p->size - size;
 		c->len = size < chunk_sz ? size : chunk_sz;
 		size -= c->len;
-		chunk_pool_add(a->cp, c);
+		if (pool_push_lock(a->chunk_pool, c) < 0) {
+			pr_err("pool_push_lock: %s", strerrno());
+			return -1;
+		}
 	} while (size > 0);
 
 	return 0;
@@ -588,6 +514,7 @@ int copy_chunk(struct chunk *c, sftp_session src_sftp, sftp_session dst_sftp,
 		return -1;
 	}
 
+	c->state = CHUNK_STATE_COPING;
 	pr_debug("copy chunk start: %s 0x%lx-0x%lx", c->p->path, c->off, c->off + c->len);
 
 	ret = _copy_chunk(c, s, d, nr_ahead, buf_sz, counter);
@@ -615,5 +542,8 @@ int copy_chunk(struct chunk *c, sftp_session src_sftp, sftp_session dst_sftp,
 		pr_info("copy done: %s", c->p->path);
 	}
 
+	if (ret == 0)
+		c->state = CHUNK_STATE_DONE;
+
 	return ret;
 }
diff --git a/src/path.h b/src/path.h
index 5c5dfc6..1db6d91 100644
--- a/src/path.h
+++ b/src/path.h
@@ -6,7 +6,6 @@
 #include <fcntl.h>
 #include <dirent.h>
 #include <sys/stat.h>
-#include <list.h>
 #include <pool.h>
 #include <atomic.h>
 #include <ssh.h>
@@ -27,44 +26,15 @@ struct path {
 #define FILE_STATE_DONE 2
 
 struct chunk {
-	struct list_head list; /* chunk_pool->list */
-
 	struct path *p;
 	size_t off; /* offset of this chunk on the file on path p */
 	size_t len; /* length of this chunk */
-	size_t done; /* copied bytes for this chunk by a thread */
-};
-
-struct chunk_pool {
-	struct list_head list; /* list of struct chunk */
-	size_t count;
-	lock lock;
 	int state;
+#define CHUNK_STATE_INIT 0
+#define CHUNK_STATE_COPING 1
+#define CHUNK_STATE_DONE 2
 };
 
-/* initialize chunk pool */
-void chunk_pool_init(struct chunk_pool *cp);
-
-/* acquire a chunk from pool. return value is NULL indicates no more
- * chunk, GET_CHUNK_WAIT means caller should waits until a chunk is
- * added, or pointer to chunk.
- */
-struct chunk *chunk_pool_pop(struct chunk_pool *cp);
-#define CHUNK_POP_WAIT ((void *)-1)
-
-/* set and check fillingchunks to this pool has finished */
-void chunk_pool_set_filled(struct chunk_pool *cp);
-bool chunk_pool_is_filled(struct chunk_pool *cp);
-
-/* return number of chunks in the pool */
-size_t chunk_pool_size(struct chunk_pool *cp);
-
-/* return true if chunk pool is empty (all chunks are already poped) */
-bool chunk_pool_is_empty(struct chunk_pool *cp);
-
-/* free chunks in the chunk_pool */
-void chunk_pool_release(struct chunk_pool *cp);
-
 struct path_resolve_args {
 	size_t *total_bytes;
 
@@ -77,7 +47,7 @@ struct path_resolve_args {
 
 	/* args to resolve chunks for a path */
 	pool *path_pool;
-	struct chunk_pool *cp;
+	pool *chunk_pool;
 	int nr_conn;
 	size_t min_chunk_sz;
 	size_t max_chunk_sz;
diff --git a/src/pool.c b/src/pool.c
index e4026ae..d67295e 100644
--- a/src/pool.c
+++ b/src/pool.c
@@ -1,4 +1,4 @@
-
+/* SPDX-License-Identifier: GPL-3.0-only */
 #include <string.h>
 #include <stdlib.h>
 #include <pool.h>
@@ -112,3 +112,12 @@ void *pool_iter_next_lock(pool *p)
 	pool_unlock(p);
 	return v;
 }
+
+bool pool_iter_check_next_lock(pool *p)
+{
+	bool next_exist;
+	pool_lock(p);
+	next_exist = (p->idx < p->num);
+	pool_unlock(p);
+	return next_exist;
+}
diff --git a/src/pool.h b/src/pool.h
index 4d8e283..875a84b 100644
--- a/src/pool.h
+++ b/src/pool.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-3.0-only */
 #ifndef _POOL_H_
 #define _POOL_H_
 
@@ -57,6 +58,7 @@ void *pool_pop_lock(pool *p);
 void *pool_get(pool *p, unsigned int idx);
 
 #define pool_size(p) ((p)->num)
+#define pool_is_empty(p) (pool_size(p) == 0)
 
 /*
  * pool->idx indicates next *v in an iteration. This has two
@@ -77,6 +79,11 @@ void *pool_get(pool *p, unsigned int idx);
 void *pool_iter_next(pool *p);
 void *pool_iter_next_lock(pool *p);
 
+/* pool_iter_check_next_lock() returns true if pool_iter_next(_lock)
+ * function will retrun a next value, otherwise false, which means
+ * there is no more values in this iteration. */
+bool pool_iter_check_next_lock(pool *p);
+
 #define pool_iter_for_each(p, v) \
 	pool_iter_init(p);       \
 	for (v = pool_iter_next(p); v != NULL; v = pool_iter_next(p))
diff --git a/test/test_e2e.py b/test/test_e2e.py
index 5e10af8..250923b 100644
--- a/test/test_e2e.py
+++ b/test/test_e2e.py
@@ -6,6 +6,7 @@ test_e2e.py: End-to-End test for mscp executable.
 import platform
 import pytest
 import getpass
+import time
 import os
 import shutil
 
@@ -318,6 +319,26 @@ def test_dont_truncate_dst(mscp, src_prefix, dst_prefix):
     f.cleanup()
 
 @pytest.mark.parametrize("src_prefix, dst_prefix", param_remote_prefix)
+def test_dont_make_conns_more_than_chunks(mscp, src_prefix, dst_prefix):
+    # copy 100 files with -n 20 -I 1 options. if mscp creates 20 SSH
+    # connections although all files have been copied, it is error.
+    srcs = []
+    dsts = []
+    for n in range(100):
+        srcs.append(File("src/src-{:06d}".format(n), size=1024).make())
+        dsts.append(File("dst/src-{:06d}".format(n)))
+    start = time.time()
+    run2ok([mscp, "-H", "-v", "-n", "20", "-I", "1",
+            src_prefix + "src/*", dst_prefix + "dst"])
+    end = time.time()
+    for s, d in zip(srcs, dsts):
+        assert check_same_md5sum(s, d)
+    shutil.rmtree("src")
+    shutil.rmtree("dst")
+    assert((end - start) < 10)
+
+
+@pytest.mark.parametrize("src_prefix, dst_prefix", param_remote_prefix)
 @pytest.mark.parametrize("src, dst", param_single_copy)
 def test_set_port(mscp, src_prefix, dst_prefix, src, dst):
     src.make()