git: 79fafc09740a - main - queue.h: Define {LIST,TAILQ}_REMOVE_HEAD

The branch main has been updated by cperciva:

URL: https://cgit.FreeBSD.org/src/commit/?id=79fafc09740ad508b40e909dc898cbac2d4f67c4

commit 79fafc09740ad508b40e909dc898cbac2d4f67c4
Author:     Colin Percival <cperciva@FreeBSD.org>
AuthorDate: 2023-07-17 23:42:50 +0000
Commit:     Colin Percival <cperciva@FreeBSD.org>
CommitDate: 2023-08-20 05:04:55 +0000

    queue.h: Define {LIST,TAILQ}_REMOVE_HEAD
    
    The LIST and TAILQ structures have fast _REMOVE macros (since each
    element has a pointer to the previous element); we implement the
    _REMOVE_HEAD macros for them by simply finding the first element and
    then removing it.
    
    Reviewed by:    jhb, emaste
    Sponsored by:   https://www.patreon.com/cperciva
    Differential Revision:  https://reviews.freebsd.org/D41072
---
 sys/sys/queue.h | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/sys/sys/queue.h b/sys/sys/queue.h
index 8e91ebf7949d..47d85121e317 100644
--- a/sys/sys/queue.h
+++ b/sys/sys/queue.h
@@ -110,7 +110,7 @@
  * _INSERT_TAIL			-	-	+	+
  * _CONCAT			s	s	+	+
  * _REMOVE_AFTER		+	-	+	-
- * _REMOVE_HEAD			+	-	+	-
+ * _REMOVE_HEAD			+	+	+	+
  * _REMOVE			s	+	s	+
  * _SWAP			+	+	+	+
  *
@@ -595,6 +595,9 @@ struct {								\
 	    __containerof((elm)->field.le_prev,			\
 	    QUEUE_TYPEOF(type), field.le_next))
 
+#define LIST_REMOVE_HEAD(head, field) 					\
+	LIST_REMOVE(LIST_FIRST(head), field)
+
 #define	LIST_REMOVE(elm, field) do {					\
 	QMD_SAVELINK(oldnext, (elm)->field.le_next);			\
 	QMD_SAVELINK(oldprev, (elm)->field.le_prev);			\
@@ -841,6 +844,9 @@ struct {								\
     ((elm)->field.tqe_prev == &(head)->tqh_first ? NULL :		\
      __containerof((elm)->field.tqe_prev, QUEUE_TYPEOF(type), field.tqe_next))
 
+#define TAILQ_REMOVE_HEAD(head, field) 					\
+	TAILQ_REMOVE(head, TAILQ_FIRST(head), field)
+
 #define	TAILQ_REMOVE(head, elm, field) do {				\
 	QMD_SAVELINK(oldnext, (elm)->field.tqe_next);			\
 	QMD_SAVELINK(oldprev, (elm)->field.tqe_prev);			\