kernel/vm/vm_rm.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  27 /*        All Rights Reserved   */
  28
  29 /*
  30  * University Copyright- Copyright (c) 1982, 1986, 1988
  31  * The Regents of the University of California
  32  * All Rights Reserved
  33  *
  34  * University Acknowledgment- Portions of this document are derived from
  35  * software developed by the University of California, Berkeley, and its
  36  * contributors.
  37  */
  38
  39 #include <sys/types.h>
  40 #include <sys/t_lock.h>
  41 #include <sys/param.h>
  42 #include <sys/systm.h>
  43 #include <sys/mman.h>
  44 #include <sys/sysmacros.h>
  45 #include <sys/errno.h>
  46 #include <sys/signal.h>
  47 #include <sys/user.h>
  48 #include <sys/proc.h>
  49 #include <sys/cmn_err.h>
  50 #include <sys/debug.h>
  51
  52 #include <vm/hat.h>
  53 #include <vm/as.h>
  54 #include <vm/seg_vn.h>
  55 #include <vm/rm.h>
  56 #include <vm/seg.h>
  57 #include <vm/page.h>
  58
  59 /*
  60  * Yield the memory claim requirement for an address space.
  61  *
  62  * This is currently implemented as the number of active hardware
  63  * translations that have page structures.  Therefore, it can
  64  * underestimate the traditional resident set size, eg, if the
  65  * physical page is present and the hardware translation is missing;
  66  * and it can overestimate the rss, eg, if there are active
  67  * translations to a frame buffer with page structs.
  68  * Also, it does not take sharing into account.
  69  */
  70 size_t
  71 rm_asrss(as)
  72         register struct as *as;
  73 {
  74         if (as != NULL && as != &kas)
  75                 return ((size_t)btop(hat_get_mapped_size(as->a_hat)));
  76         else
  77                 return (0);
  78 }
  79
  80 /*
  81  * Return a 16-bit binary fraction representing the percent of total memory
  82  * used by this address space.  Binary point is to right of high-order bit.
  83  * Defined as the ratio of a_rss for the process to total physical memory.
  84  * This assumes 2s-complement arithmetic and that shorts and longs are
  85  * 16 bits and 32 bits, respectively.
  86  */
  87 ushort_t
  88 rm_pctmemory(struct as *as)
  89 {
  90         /* This can't overflow */
  91         ulong_t num = (ulong_t)rm_asrss(as) << (PAGESHIFT-1);
  92         int shift = 16 - PAGESHIFT;
  93         ulong_t total = total_pages;
  94
  95         if (shift < 0) {
  96                 num >>= (-shift);
  97                 shift = 0;
  98         }
  99         while (shift > 0 && (num & 0x80000000) == 0) {
 100                 shift--;
 101                 num <<= 1;
 102         }
 103         if (shift > 0)
 104                 total >>= shift;
 105
 106         return (num / total);
 107 }