hlist: drop the node parameter from iterators

I'm not sure why, but the hlist for each entry iterators were conceived

        list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

        hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

 - Fix up the actual hlist iterators in linux/list.h
 - Fix up the declaration of other iterators based on the hlist ones.
 - A very small amount of places were using the 'node' parameter, this
 was modified to use 'obj->member' instead.
 - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
 properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
    <+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
    ...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 19 insertions, 21 deletions

diff --git a/include/linux/hashtable.h b/include/linux/hashtable.h
index 227c62424f3c..a9df51f5d54c 100644
--- a/include/linux/hashtable.h
+++ b/include/linux/hashtable.h
@@ -115,51 +115,50 @@ static inline void hash_del_rcu(struct hlist_node *node)
  * hash_for_each - iterate over a hashtable
  * @name: hashtable to iterate
  * @bkt: integer to use as bucket loop cursor
- * @node: the &struct list_head to use as a loop cursor for each entry
  * @obj: the type * to use as a loop cursor for each entry
  * @member: the name of the hlist_node within the struct
  */
-#define hash_for_each(name, bkt, node, obj, member)				\
-	for ((bkt) = 0, node = NULL; node == NULL && (bkt) < HASH_SIZE(name); (bkt)++)\
-		hlist_for_each_entry(obj, node, &name[bkt], member)
+#define hash_for_each(name, bkt, obj, member)				\
+	for ((bkt) = 0, obj = NULL; obj == NULL && (bkt) < HASH_SIZE(name);\
+			(bkt)++)\
+		hlist_for_each_entry(obj, &name[bkt], member)
 
 /**
  * hash_for_each_rcu - iterate over a rcu enabled hashtable
  * @name: hashtable to iterate
  * @bkt: integer to use as bucket loop cursor
- * @node: the &struct list_head to use as a loop cursor for each entry
  * @obj: the type * to use as a loop cursor for each entry
  * @member: the name of the hlist_node within the struct
  */
-#define hash_for_each_rcu(name, bkt, node, obj, member)				\
-	for ((bkt) = 0, node = NULL; node == NULL && (bkt) < HASH_SIZE(name); (bkt)++)\
-		hlist_for_each_entry_rcu(obj, node, &name[bkt], member)
+#define hash_for_each_rcu(name, bkt, obj, member)			\
+	for ((bkt) = 0, obj = NULL; obj == NULL && (bkt) < HASH_SIZE(name);\
+			(bkt)++)\
+		hlist_for_each_entry_rcu(obj, &name[bkt], member)
 
 /**
  * hash_for_each_safe - iterate over a hashtable safe against removal of
  * hash entry
  * @name: hashtable to iterate
  * @bkt: integer to use as bucket loop cursor
- * @node: the &struct list_head to use as a loop cursor for each entry
  * @tmp: a &struct used for temporary storage
  * @obj: the type * to use as a loop cursor for each entry
  * @member: the name of the hlist_node within the struct
  */
-#define hash_for_each_safe(name, bkt, node, tmp, obj, member)			\
-	for ((bkt) = 0, node = NULL; node == NULL && (bkt) < HASH_SIZE(name); (bkt)++)\
-		hlist_for_each_entry_safe(obj, node, tmp, &name[bkt], member)
+#define hash_for_each_safe(name, bkt, tmp, obj, member)			\
+	for ((bkt) = 0, obj = NULL; obj == NULL && (bkt) < HASH_SIZE(name);\
+			(bkt)++)\
+		hlist_for_each_entry_safe(obj, tmp, &name[bkt], member)
 
 /**
  * hash_for_each_possible - iterate over all possible objects hashing to the
  * same bucket
  * @name: hashtable to iterate
  * @obj: the type * to use as a loop cursor for each entry
- * @node: the &struct list_head to use as a loop cursor for each entry
  * @member: the name of the hlist_node within the struct
  * @key: the key of the objects to iterate over
  */
-#define hash_for_each_possible(name, obj, node, member, key)			\
-	hlist_for_each_entry(obj, node,	&name[hash_min(key, HASH_BITS(name))], member)
+#define hash_for_each_possible(name, obj, member, key)			\
+	hlist_for_each_entry(obj, &name[hash_min(key, HASH_BITS(name))], member)
 
 /**
  * hash_for_each_possible_rcu - iterate over all possible objects hashing to the
@@ -167,25 +166,24 @@ static inline void hash_del_rcu(struct hlist_node *node)
  * in a rcu enabled hashtable
  * @name: hashtable to iterate
  * @obj: the type * to use as a loop cursor for each entry
- * @node: the &struct list_head to use as a loop cursor for each entry
  * @member: the name of the hlist_node within the struct
  * @key: the key of the objects to iterate over
  */
-#define hash_for_each_possible_rcu(name, obj, node, member, key)		\
-	hlist_for_each_entry_rcu(obj, node, &name[hash_min(key, HASH_BITS(name))], member)
+#define hash_for_each_possible_rcu(name, obj, member, key)		\
+	hlist_for_each_entry_rcu(obj, &name[hash_min(key, HASH_BITS(name))],\
+		member)
 
 /**
  * hash_for_each_possible_safe - iterate over all possible objects hashing to the
  * same bucket safe against removals
  * @name: hashtable to iterate
  * @obj: the type * to use as a loop cursor for each entry
- * @node: the &struct list_head to use as a loop cursor for each entry
  * @tmp: a &struct used for temporary storage
  * @member: the name of the hlist_node within the struct
  * @key: the key of the objects to iterate over
  */
-#define hash_for_each_possible_safe(name, obj, node, tmp, member, key)		\
-	hlist_for_each_entry_safe(obj, node, tmp,				\
+#define hash_for_each_possible_safe(name, obj, tmp, member, key)	\
+	hlist_for_each_entry_safe(obj, tmp,\
 		&name[hash_min(key, HASH_BITS(name))], member)