4 files changed, 175 insertions(+), 23 deletions(-)

A port/alloc.c
M port/malloc.c
M port/page.c
M power/devcyc.c

@@ 0,0 1,150 @@
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#define	nil	((void*)0)
+#define datoff	((int)&((Xhdr*)0)->data)
+
+enum
+{
+	Nhole	= 128,
+	Magic	= 0xDeadBabe,
+};
+
+typedef struct Hole Hole;
+typedef struct Xalloc Xalloc;
+typedef struct Xhdr Xhdr;
+struct Hole
+{
+	ulong	addr;
+	ulong	size;
+	ulong	top;
+	Hole	*link;
+};
+
+struct Xhdr
+{
+	ulong	size;
+	ulong	magix;
+	char	data[1];
+};
+
+struct Xalloc
+{
+	Lock;
+	Hole	hole[Nhole];
+	Hole	*flist;
+	Hole	*table;
+};
+
+Xalloc	xlists;
+
+void
+xinit(void)
+{
+	Hole *h, *eh;
+
+	eh = &xlists.hole[Nhole-1];
+	for(h = xlists.hole; h < eh; h++)
+		h->link = h+1;
+
+	xlists.flist = h;
+}
+
+void
+xhole(ulong addr, ulong size)
+{
+	Hole *h, **l;
+
+	lock(&xlists);
+	l = &xlists.table;
+	for(h = *l; h; h = h->link) {
+		if(h->top == addr) {
+			h->size += size;
+			h->top = h->addr+h->size;
+			unlock(&xlists);
+			return;
+		}
+		if(h->addr > addr)
+			break;
+		l = &h->link;
+	}
+
+	if(xlists.flist == nil) {
+		print("xfree: no free holes, leaked %d bytes\n", size);
+		unlock(&xlists);
+		return;
+	}
+
+	h = xlists.flist;
+	xlists.flist = h->link;
+	h->addr = addr;
+	h->top = addr+size;
+	h->size = size;
+	h->link = *l;
+	*l = h;
+	unlock(&xlists);
+}
+
+void*
+xalloc(ulong size)
+{
+	Hole *h, **l;
+	Xhdr *p;
+
+	size += sizeof(Xhdr);
+
+	lock(&xlists);
+	l = &xlists.table;
+	for(h = *l; h; h = h->link) {
+		if(h->size >= size) {
+			p = (Xhdr*)h->addr;
+			h->addr += size;
+			h->size -= size;
+			if(h->size == 0) {
+				*l = h->link;
+				h->link = xlists.flist;
+				xlists.flist = h;
+			}
+			p->magix = Magic;
+			p->size = size;
+			unlock(&xlists);
+			return p->data;
+		}
+		l = &h->link;
+	}
+	unlock(&xlists);
+	return nil;
+}
+
+void
+xfree(void *p)
+{
+	Xhdr *x;
+
+	x = (Xhdr*)((ulong)p - datoff);
+	if(x->magix != Magic)
+		panic("xfree");
+
+	xhole((ulong)x, x->size);
+}
+
+void
+xsummary(void)
+{
+	int i;
+	Hole *h;
+
+	i = 0;
+	for(h = xlists.flist; h; h = h->link)
+		i++;
+
+	print("%d holes free\n", i);
+	i = 0;
+	for(h = xlists.table; h; h = h->link) {
+		print("%lux %lux %d\n", h->addr, h->top, h->size);
+		i += h->size;
+	}
+	print("%d bytes free\n", i);
+}

@@ 4,7 4,7 @@
 enum
 {
 	MAGIC		= 0xDEADBABE,
-	MAX2SIZE	= 20
+	MAXPOW		= 20
 };
 
 typedef struct Bucket Bucket;


@@ 20,9 20,8 @@ typedef struct Arena Arena;
 struct Arena
 {
 	Lock;
-	Bucket	*btab[MAX2SIZE];	
+	Bucket	*btab[MAXPOW];
 };
-
 static Arena arena;
 #define datoff		((int)&((Bucket*)0)->data)
 


@@ 32,14 31,15 @@ malloc(uint size)
 	int pow;
 	Bucket *bp;
 
-	for(pow = 1; pow < MAX2SIZE; pow++) {
+	size += sizeof(Bucket);
+
+	for(pow = 1; pow < MAXPOW; pow++)
 		if(size <= (1<<pow))
 			goto good;
-	}
 
-	return nil;
+	return 0;
+
 good:
-	/* Allocate off this list */
 	lock(&arena);
 	bp = arena.btab[pow];
 	if(bp) {


@@ 47,7 47,7 @@ good:
 		arena.unlock();
 
 		if(bp->magic != 0)
-			abort();
+			panic("malloc");
 
 		bp->magic = MAGIC;
 


@@ 55,14 55,13 @@ good:
 		return  bp->data;
 	}
 	unlock(&arena);
+
 	size = sizeof(Bucket)+(1<<pow);
-	bp = sbrk(size);
+	bp = xbrk(size);
 	if((int)bp < 0)
 		return nil;
 
-	bp->size = pow;
-	bp->magic = MAGIC;
-
+	memset(bp->data, 0,  size);
 	return bp->data;
 }
 

@@ 66,11 66,14 @@ Region region[Nregion];
 void
 addsplit(Region *r, ulong start, ulong end)
 {
-	Region *rr;
-	int len = end - start;
+	int len;
+	Region *rr, *eregion;
+
+	len = end - start;
+	eregion = &region[Nregion];
 
 	/* first look for an unused one */
-	for(rr = region; rr < &region[Nregion]; rr++){
+	for(rr = region; rr < eregion; rr++){
 		if(rr == r)
 			continue;
 		if(rr->end - rr->start == 0){


@@ 81,7 84,7 @@ addsplit(Region *r, ulong start, ulong end)
 	}
 
 	/* then look for a smaller one */
-	for(rr = region; rr < &region[Nregion]; rr++){
+	for(rr = region; rr < eregion; rr++){
 		if(rr == r)
 			continue;
 		if(rr->end - rr->start < len){


@@ 105,19 108,21 @@ addsplit(Region *r, ulong start, ulong end)
 void*
 iallocspan(ulong n, int align, ulong crevasse)
 {
+	int m;
 	ulong p;
 	Region *r;
-	int m;
 	int ledge;
 
 	if(palloc.active && n!=0)
 		print("ialloc bad\n");
 
 	if(palloc.addr0 == 0){
-		region[Nregion-2].start = (((ulong)end)&~KZERO) + conf.base0;
-		region[Nregion-2].end = conf.base0 + (conf.npage0<<PGSHIFT);
-		region[Nregion-1].start = conf.base1;
-		region[Nregion-1].end = conf.base1 + (conf.npage1<<PGSHIFT);
+		r = &region[Nregion-2];
+		r->start = (((ulong)end)&~KZERO) + conf.base0;
+		r->end = conf.base0 + (conf.npage0<<PGSHIFT);
+		r++;
+		r->start = conf.base1;
+		r->end = conf.base1 + (conf.npage1<<PGSHIFT);
 
 		palloc.addr0 = region[Nregion-2].start;
 		palloc.addr1 = region[Nregion-1].start;


@@ 174,7 179,6 @@ iallocspan(ulong n, int align, ulong crevasse)
 	 *  zero it
 	 */
 	memset((void*)(p|KZERO), 0, n);
-
 	return (void*)(p|KZERO);
 }
 

@@ 204,7 204,6 @@ cycclose(Chan *c)
 	}
 }
 
-
 int
 cycmsgintr(Cycmsg *hm)
 {