9os

commit b84d3c24b90fd23b9aa8808ec9ec66995bac2301
parent 4bf8e34798442687c59ed815248bdc4ab71e8759
Author: Roberto E. Vargas Caballero <roberto.vargas@midokura.com>
Date:   Fri, 18 Nov 2022 14:43:52 +0100

os9: Add freemap()

We add a pool of objects that can be reused if they are freed.

Diffstat:
M
include/os9/os9.h
 | 
1
+
M
src/os9/proc.c
 | 
21
++++++++++++++++++---

2 files changed, 19 insertions(+), 3 deletions(-)
diff --git a/include/os9/os9.h b/include/os9/os9.h
@@ -112,6 +112,7 @@ struct map {
 	phyaddr_t pa;
 	uintptr_t va;
 	size_t siz;
+	Map *next;
 };
 
 /*
diff --git a/src/os9/proc.c b/src/os9/proc.c
@@ -18,6 +18,11 @@ static struct {
 	mutex_t m;
 } fdspool;
 
+static struct {
+	Map *list;
+	mutex_t m;
+} mappool;
+
 /* per cpu globals */
 Task *proc;
 long long now;
@@ -298,8 +303,15 @@ newmap(Map *from)
 {
 	Map *mp;
 
-	if ((mp = alloc(sizeof(*mp))) == NULL)
-		return NULL;
+	lock(&mappool.m);
+	if (mappool.list) {
+		mp = mappool.list;
+		mappool.list = mp->next;
+	} else {
+		if ((mp = alloc(sizeof(*mp))) == NULL)
+			return NULL;
+	}
+	unlock(&mappool.m);
 
 	*mp = *from;
 	initref(&mp->ref);
@@ -329,7 +341,10 @@ freefds(Fdset *fds)
 static void
 freemap(Map *mp)
 {
-	/* TODO */
+	lock(&mappool.m);
+	mp->next = mappool.list;
+	mappool.list = mp;
+	unlock(&mappool.m);
 }
 
 static void