shithub: riscv

Download patch

ref: b8cf3cb879a19c001796329ebe266104d13e63be
parent: f215b660b30cc5e5d318922f545441b4ac14b200
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Fri Feb 6 21:52:23 EST 2015 

kernel: reduce Page structure size by changing Page.cachectl[]

there are no kernels currently that do page coloring,
so the only use of cachectl[] is flushing the icache
(on arm and ppc).

on pc64, cachectl consumes 32 bytes in each page resulting
in over 200 megabytes of overhead for 32gb of ram with 4K
pages.

this change removes cachectl[] and adds txtflush ulong
that is set to ~0 by pio() to instruct putmmu() to flush
the icache.


--- a/sys/src/9/alphapc/main.c
+++ b/sys/src/9/alphapc/main.c
@@ -255,7 +255,7 @@
 	s->flushme++;
 	p->seg[TSEG] = s;
 	pg = newpage(1, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	k = kmap(s->map[0]->pages[0]);
 	memmove((uchar*)VA(k), initcode, sizeof initcode);
--- a/sys/src/9/bcm/main.c
+++ b/sys/src/9/bcm/main.c
@@ -413,7 +413,7 @@
 	s = newseg(SG_TEXT, UTZERO, 1);
 	p->seg[TSEG] = s;
 	pg = newpage(1, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	k = kmap(s->map[0]->pages[0]);
 	memmove(UINT2PTR(VA(k)), initcode, sizeof initcode);
--- a/sys/src/9/bcm/mmu.c
+++ b/sys/src/9/bcm/mmu.c
@@ -265,10 +265,9 @@
 	 *  rather than direct mapped.
 	 */
 	cachedwbinv();
-	if(page->cachectl[0] == PG_TXTFLUSH){
-		/* pio() sets PG_TXTFLUSH whenever a text pg has been written */
+	if(page->txtflush){
 		cacheiinv();
-		page->cachectl[0] = PG_NOFLUSH;
+		page->txtflush = 0;
 	}
 	checkmmu(va, PPN(pa));
 }
--- a/sys/src/9/bitsy/main.c
+++ b/sys/src/9/bitsy/main.c
@@ -225,7 +225,7 @@
 	s = newseg(SG_TEXT, UTZERO, 1);
 	p->seg[TSEG] = s;
 	pg = newpage(1, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	k = kmap(s->map[0]->pages[0]);
 	memmove((ulong*)VA(k), initcode, sizeof initcode);
--- a/sys/src/9/bitsy/mmu.c
+++ b/sys/src/9/bitsy/mmu.c
@@ -406,10 +406,9 @@
 	 *  rather than direct mapped.
 	 */
 	cachewb();
-	if(pg->cachectl[0] == PG_TXTFLUSH){
-		/* pio() sets PG_TXTFLUSH whenever a text page has been written */
+	if(pg->txtflush){
 		icacheinvalidate();
-		pg->cachectl[0] = PG_NOFLUSH;
+		pg->txtflush = 0;
 	}
 
 	splx(s);
--- a/sys/src/9/kw/main.c
+++ b/sys/src/9/kw/main.c
@@ -587,7 +587,7 @@
 	s->flushme++;
 	p->seg[TSEG] = s;
 	pg = newpage(1, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	k = kmap(s->map[0]->pages[0]);
 	memmove(UINT2PTR(VA(k)), initcode, sizeof initcode);
--- a/sys/src/9/kw/mmu.c
+++ b/sys/src/9/kw/mmu.c
@@ -353,10 +353,9 @@
 	 *  rather than direct mapped.
 	 */
 	cachedwbinv();
-	if(page->cachectl[0] == PG_TXTFLUSH){
-		/* pio() sets PG_TXTFLUSH whenever a text pg has been written */
+	if(page->txtflush){
 		cacheiinv();
-		page->cachectl[0] = PG_NOFLUSH;
+		page->txtflush = 0;
 	}
 	//print("putmmu %#p %#p %#p\n", va, pa, PPN(pa)|x);
 }
--- a/sys/src/9/mtx/main.c
+++ b/sys/src/9/mtx/main.c
@@ -198,7 +198,7 @@
 	s->flushme++;
 	p->seg[TSEG] = s;
 	pg = newpage(1, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	k = kmap(s->map[0]->pages[0]);
 	memmove((ulong*)VA(k), initcode, sizeof initcode);
--- a/sys/src/9/mtx/mmu.c
+++ b/sys/src/9/mtx/mmu.c
@@ -179,7 +179,6 @@
 putmmu(uintptr va, uintptr pa, Page *pg)
 {
 	int mp;
-	char *ctl;
 	ulong *p, *ep, *q, pteg;
 	ulong vsid, ptehi, x, hash;
 
@@ -218,19 +217,10 @@
 	q[1] = pa;
 	sync();
 
-	ctl = &pg->cachectl[m->machno];
-	switch(*ctl) {
-	case PG_NEWCOL:
-	default:
-		panic("putmmu: %d\n", *ctl);
-		break;
-	case PG_NOFLUSH:
-		break;
-	case PG_TXTFLUSH:
+	if(pg->txtflush & (1<<m->machno)){
 		dcflush((void*)pg->va, BY2PG);
 		icflush((void*)pg->va, BY2PG);
-		*ctl = PG_NOFLUSH;
-		break;
+		pg->txtflush &= ~(1<<m->machno);
 	}
 }
 
--- a/sys/src/9/omap/main.c
+++ b/sys/src/9/omap/main.c
@@ -565,7 +565,7 @@
 	s = newseg(SG_TEXT, UTZERO, 1);
 	p->seg[TSEG] = s;
 	pg = newpage(1, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	k = kmap(s->map[0]->pages[0]);
 	memmove(UINT2PTR(VA(k)), initcode, sizeof initcode);
--- a/sys/src/9/omap/mmu.c
+++ b/sys/src/9/omap/mmu.c
@@ -330,10 +330,9 @@
 	 *  rather than direct mapped.
 	 */
 	cachedwbinv();
-	if(page->cachectl[0] == PG_TXTFLUSH){
-		/* pio() sets PG_TXTFLUSH whenever a text pg has been written */
+	if(page->txtflush){
 		cacheiinv();
-		page->cachectl[0] = PG_NOFLUSH;
+		page->txtflush = 0;
 	}
 	//print("putmmu %#p %#p %#p\n", va, pa, PPN(pa)|x);
 }
--- a/sys/src/9/omap4/main.c
+++ b/sys/src/9/omap4/main.c
@@ -134,7 +134,7 @@
 	s->flushme++;
 	p->seg[TSEG] = s;
 	pg = newpage(0, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	v = vmap(pg->pa, BY2PG);
 	memset(v, 0, BY2PG);
--- a/sys/src/9/pc/main.c
+++ b/sys/src/9/pc/main.c
@@ -307,7 +307,7 @@
 	s->flushme++;
 	p->seg[TSEG] = s;
 	pg = newpage(0, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	v = tmpmap(pg);
 	memset(v, 0, BY2PG);
--- a/sys/src/9/pc64/main.c
+++ b/sys/src/9/pc64/main.c
@@ -461,7 +461,7 @@
 	s->flushme++;
 	p->seg[TSEG] = s;
 	pg = newpage(0, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	v = kmap(pg);
 	memset(v, 0, BY2PG);
--- a/sys/src/9/port/devproc.c
+++ b/sys/src/9/port/devproc.c
@@ -1580,12 +1580,12 @@
 		memmove(b, a, n);
 	kunmap(k);
 
-	/* Ensure the process sees text page changes */
-	if(s->flushme)
-		memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
-
-	if(!read)
+	if(!read){
+		/* Ensure the process sees text page changes */
+		if(s->flushme)
+			pg->txtflush = ~0;
 		p->newtlb = 1;
+	}
 
 	qunlock(s);
 	poperror();
--- a/sys/src/9/port/fault.c
+++ b/sys/src/9/port/fault.c
@@ -187,7 +187,7 @@
 done:
 	putpage(new);
 	if(s->flushme)
-		memset((*p)->cachectl, PG_TXTFLUSH, sizeof((*p)->cachectl));
+		(*p)->txtflush = ~0;
 }
 
 void	(*checkaddr)(uintptr, Segment *, Page *);
@@ -263,6 +263,8 @@
 			new = newpage(0, &s, addr);
 			if(s == nil)
 				return -1;
+			if(s->flushme)
+				new->txtflush = ~0;
 			*pg = new;
 			copypage(old, *pg);
 			putpage(old);
--- a/sys/src/9/port/page.c
+++ b/sys/src/9/port/page.c
@@ -145,8 +145,7 @@
 {
 	Page *p, **l;
 	KMap *k;
-	uchar ct;
-	int i, color;
+	int color;
 
 	color = getpgcolor(va);
 	lock(&palloc);
@@ -195,12 +194,9 @@
 		l = &p->next;
 	}
 
-	ct = PG_NOFLUSH;
 	if(p == nil) {
 		l = &palloc.head;
 		p = *l;
-		p->color = color;
-		ct = PG_NEWCOL;
 	}
 
 	*l = p->next;
@@ -211,8 +207,7 @@
 	p->ref = 1;
 	p->va = va;
 	p->modref = 0;
-	for(i = 0; i < MAXMACH; i++)
-		p->cachectl[i] = ct;
+	p->txtflush = 0;
 
 	if(clear) {
 		k = kmap(p);
--- a/sys/src/9/port/portdat.h
+++ b/sys/src/9/port/portdat.h
@@ -292,11 +292,6 @@
 
 enum
 {
-	PG_NOFLUSH	= 0,
-	PG_TXTFLUSH	= 1,		/* flush dcache and invalidate icache */
-	PG_DATFLUSH	= 2,		/* flush both i & d caches (UNUSED) */
-	PG_NEWCOL	= 3,		/* page has been recolored */
-
 	PG_MOD		= 0x01,		/* software modified bit */
 	PG_REF		= 0x02,		/* software referenced bit */
 };
@@ -309,10 +304,10 @@
 	uintptr	va;			/* Virtual address for user */
 	uintptr	daddr;			/* Disc address on swap */
 	Image	*image;			/* Associated text or swap image */
+	ulong	txtflush;		/* Flush icache for putmmu */
 	ushort	refage;			/* Swap reference age */
 	char	modref;			/* Simulated modify/reference bits */
 	char	color;			/* Cache coloring */
-	char	cachectl[MAXMACH];	/* Cache flushing control for putmmu */
 };
 
 struct Swapalloc
--- a/sys/src/9/port/segment.c
+++ b/sys/src/9/port/segment.c
@@ -669,7 +669,7 @@
 	for(i = s; i < e; i++) {
 		pg = pte->pages[i];
 		if(!pagedout(pg))
-			memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+			pg->txtflush = ~0;
 	}
 }
 
--- a/sys/src/9/ppc/main.c
+++ b/sys/src/9/ppc/main.c
@@ -233,7 +233,7 @@
 	s->flushme++;
 	p->seg[TSEG] = s;
 	pg = newpage(1, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	k = kmap(s->map[0]->pages[0]);
 	memmove((ulong*)VA(k), initcode, sizeof initcode);
--- a/sys/src/9/ppc/mmu.c
+++ b/sys/src/9/ppc/mmu.c
@@ -199,7 +199,6 @@
 putmmu(uintptr va, uintptr pa, Page *pg)
 {
 	int mp;
-	char *ctl;
 	ulong *p, *ep, *q, pteg;
 	ulong vsid, hash;
 	ulong ptehi, x;
@@ -244,21 +243,11 @@
 	q[0] = ptehi;
 	q[1] = pa;
 
-	ctl = &pg->cachectl[m->machno];
-	switch(*ctl) {
-	case PG_NEWCOL:
-	default:
-		panic("putmmu: %d\n", *ctl);
-		break;
-	case PG_TXTFLUSH:
+	if(pg->txtflush & (1<<m->machno)){
 		dcflush((void*)pg->va, BY2PG);
 		icflush((void*)pg->va, BY2PG);
-		*ctl = PG_NOFLUSH;
-		break;
-	case PG_NOFLUSH:
-		break;
+		pg->txtflush &= ~(1<<m->machno);
 	}
-
 }
 
 void
--- a/sys/src/9/teg2/main.c
+++ b/sys/src/9/teg2/main.c
@@ -792,7 +792,7 @@
 	s = newseg(SG_TEXT, UTZERO, 1);
 	p->seg[TSEG] = s;
 	pg = newpage(1, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	k = kmap(s->map[0]->pages[0]);
 	memmove(UINT2PTR(VA(k)), initcode, sizeof initcode);
--- a/sys/src/9/teg2/mmu.c
+++ b/sys/src/9/teg2/mmu.c
@@ -582,10 +582,9 @@
 	 */
 	l1cache->wb();
 
-	if(page->cachectl[0] == PG_TXTFLUSH){
-		/* pio() sets PG_TXTFLUSH whenever a text pg has been written */
+	if(page->txtflush & (1<<m->machno)){
 		cacheiinv();
-		page->cachectl[0] = PG_NOFLUSH;
+		page->txtflush &= ~(1<<m->machno);
 	}
 	if (Debug)
 		iprint("putmmu %#p %#p %#p\n", va, pa, PPN(pa)|x);
--- a/sys/src/9/xen/main.c
+++ b/sys/src/9/xen/main.c
@@ -245,7 +245,7 @@
 	s->flushme++;
 	p->seg[TSEG] = s;
 	pg = newpage(1, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 	segpage(s, pg);
 	k = kmap(s->map[0]->pages[0]);
 	memmove((ulong*)VA(k), initcode, sizeof initcode);
--- a/sys/src/9/zynq/main.c
+++ b/sys/src/9/zynq/main.c
@@ -306,7 +306,7 @@
 	s->flushme++;
 	p->seg[TSEG] = s;
 	pg = newpage(0, 0, UTZERO);
-	memset(pg->cachectl, PG_TXTFLUSH, sizeof(pg->cachectl));
+	pg->txtflush = ~0;
 
 	segpage(s, pg);
 	v = tmpmap(pg->pa);
--- a/sys/src/9/zynq/mmu.c
+++ b/sys/src/9/zynq/mmu.c
@@ -140,7 +140,6 @@
 	ulong *e;
 	ulong *l2;
 	PTE old;
-	char *ctl;
 	uintptr l2p;
 	int s;
 
@@ -180,11 +179,10 @@
 	splx(s);
 	if((old & L2VALID) != 0)
 		flushpg((void *) va);
-	ctl = &pg->cachectl[m->machno];
-	if(*ctl == PG_TXTFLUSH){
+	if(pg->txtflush & (1<<m->machno)){
 		cleandse((void *) va, (void *) (va + BY2PG));
 		invalise((void *) va, (void *) (va + BY2PG));
-		*ctl = PG_NOFLUSH;
+		pg->txtflush &= ~(1<<m->machno);
 	}
 }