Dynamic buffer cache. Initial diff from mickey@, okay art@ beck@ toby@

deraadt@ dlg@.

1 files changed, 8 insertions, 83 deletions

diff --git a/sys/arch/sparc64/sparc64/machdep.c b/sys/arch/sparc64/sparc64/machdep.c
index 229efbf7b1d..f0e910a0351 100644
--- a/sys/arch/sparc64/sparc64/machdep.c
+++ b/sys/arch/sparc64/sparc64/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.88 2007/05/23 20:33:47 pvalchev Exp $	*/
+/*	$OpenBSD: machdep.c,v 1.89 2007/05/26 20:26:51 pedro Exp $	*/
 /*	$NetBSD: machdep.c,v 1.108 2001/07/24 19:30:14 eeh Exp $ */
 
 /*-
@@ -172,14 +172,8 @@ extern vaddr_t avail_end;
 /*
  * Declare these as initialized data so we can patch them.
  */
-#ifdef	NBUF
-int	nbuf = NBUF;
-#else
-int	nbuf = 0;
-#endif
-
 #ifndef BUFCACHEPERCENT
-#define BUFCACHEPERCENT 5
+#define BUFCACHEPERCENT 10
 #endif
 
 #ifdef	BUFPAGES
@@ -232,16 +226,13 @@ void	stackdump(void);
 void
 cpu_startup()
 {
-	unsigned i;
 	caddr_t v;
 	long sz;
-	int base, residual;
 #ifdef DEBUG
 	extern int pmapdebug;
 	int opmapdebug = pmapdebug;
 #endif
 	vaddr_t minaddr, maxaddr;
-	vsize_t size;
 	extern struct user *proc0paddr;
 
 #ifdef DEBUG
@@ -267,52 +258,12 @@ cpu_startup()
 	if (allocsys(v) - v != sz)
 		panic("startup: table size inconsistency");
 
-        /*
-         * allocate virtual and physical memory for the buffers.
-         */
-        size = MAXBSIZE * nbuf;         /* # bytes for buffers */
-
-        /* allocate VM for buffers... area is not managed by VM system */
-        if (uvm_map(kernel_map, (vaddr_t *) &buffers, round_page(size),
-                    NULL, UVM_UNKNOWN_OFFSET, 0,
-                    UVM_MAPFLAG(UVM_PROT_NONE, UVM_PROT_NONE, UVM_INH_NONE,
-                                UVM_ADV_NORMAL, 0)) != 0)
-        	panic("cpu_startup: cannot allocate VM for buffers");
-
-        minaddr = (vaddr_t) buffers;
-        if ((bufpages / nbuf) >= btoc(MAXBSIZE)) {
-        	bufpages = btoc(MAXBSIZE) * nbuf; /* do not overallocate RAM */
-        }
-        base = bufpages / nbuf;
-        residual = bufpages % nbuf;
-
-        /* now allocate RAM for buffers */
-	for (i = 0 ; i < nbuf ; i++) {
-		vaddr_t curbuf;
-		vsize_t curbufsize;
-		struct vm_page *pg;
-
-		/*
-		 * each buffer has MAXBSIZE bytes of VM space allocated.  of
-		 * that MAXBSIZE space we allocate and map (base+1) pages
-		 * for the first "residual" buffers, and then we allocate
-		 * "base" pages for the rest.
-		 */
-		curbuf = (vaddr_t) buffers + (i * MAXBSIZE);
-		curbufsize = NBPG * ((i < residual) ? (base+1) : base);
-
-		while (curbufsize) {
-			pg = uvm_pagealloc(NULL, 0, NULL, 0);
-			if (pg == NULL)
-				panic("cpu_startup: "
-				    "not enough RAM for buffer cache");
-			pmap_kenter_pa(curbuf,
-			    VM_PAGE_TO_PHYS(pg), VM_PROT_READ|VM_PROT_WRITE);
-			curbuf += PAGE_SIZE;
-			curbufsize -= PAGE_SIZE;
-		}
-	}
-	pmap_update(pmap_kernel());
+	/*
+	 * Determine how many buffers to allocate.
+	 * We allocate bufcachepercent% of memory for buffer space.
+	 */
+	if (bufpages == 0)
+		bufpages = physmem * bufcachepercent / 100;
 
 	/*
 	 * Allocate a submap for exec arguments.  This map effectively
@@ -327,8 +278,6 @@ cpu_startup()
 #endif
 	printf("avail mem = %lu (%luMB)\n", ptoa(uvmexp.free),
 	    ptoa(uvmexp.free)/1024/1024);
-	printf("using %d buffers containing %ld bytes of memory\n", nbuf,
-		(long)bufpages * PAGE_SIZE);
 
 	/*
 	 * Set up buffers, so they can be used to read disk labels.
@@ -352,30 +301,6 @@ allocsys(caddr_t v)
 	valloc(msqids, struct msqid_ds, msginfo.msgmni);
 #endif
 
-        /*
-	 * Determine how many buffers to allocate (enough to
-	 * hold 5% of total physical memory, but at least 16).
-	 * Allocate 1/2 as many swap buffer headers as file i/o buffers.
-	 */
-	 if (bufpages == 0)
-	 	bufpages = physmem * bufcachepercent / 100;
-	 if (nbuf == 0) {
-	 	nbuf = bufpages;
-		if (nbuf < 16)
-			nbuf = 16;
-	}
-	/* Restrict to at most 30% filled kvm */
-	if (nbuf * MAXBSIZE >
-	    (KERNEND - KERNBASE) * 3 / 10)
-		nbuf = (KERNEND - KERNBASE) /
-		    MAXBSIZE * 3 / 10;
-
-	/* More buffer pages than fits into the buffers is senseless.  */
-	if (bufpages > nbuf * MAXBSIZE / PAGE_SIZE)
-		bufpages = nbuf * MAXBSIZE / PAGE_SIZE;
-
-	valloc(buf, struct buf, nbuf);
-
 	return (v);
 }