mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

net: core: another layer of lists, around PF_MEMALLOC skb handling 

[ Upstream commit 78ed8cc25986ac5c21762eeddc1e86e94d422e36 ]

First example of a layer splitting the list (rather than merely taking
 individual packets off it).
Involves new list.h function, list_cut_before(), like list_cut_position()
 but cuts on the other side of the given entry.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[sl: cut out non list.h bits, we only want list_cut_before]
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Sasha Levin 2019-05-16 21:30:49 -04:00 committed by Greg Kroah-Hartman
parent e6fedb8802
commit ba16982371
1 changed files with 30 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

30
include/linux/list.h
View File

@ -285,6 +285,36 @@ static inline void list_cut_position(struct list_head *list,
__list_cut_position(list, head, entry);
}
/**
* list_cut_before - cut a list into two, before given entry
* @list: a new list to add all removed entries
* @head: a list with entries
* @entry: an entry within head, could be the head itself
*
* This helper moves the initial part of @head, up to but
* excluding @entry, from @head to @list. You should pass
* in @entry an element you know is on @head. @list should
* be an empty list or a list you do not care about losing
* its data.
* If @entry == @head, all entries on @head are moved to
* @list.
*/
static inline void list_cut_before(struct list_head *list,
struct list_head *head,
struct list_head *entry)
{
if (head->next == entry) {
INIT_LIST_HEAD(list);
return;
}
list->next = head->next;
list->next->prev = list;
list->prev = entry->prev;
list->prev->next = list;
head->next = entry;
entry->prev = head;
}
static inline void __list_splice(const struct list_head *list,
struct list_head *prev,
struct list_head *next)