sys/cddl/dev/dtrace/dtrace_vtime.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  * $FreeBSD$
  22  */
  23
  24 /*
  25  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28
  29 void
  30 dtrace_vtime_enable(void)
  31 {
  32         dtrace_vtime_state_t state, nstate = 0;
  33
  34         do {
  35                 state = dtrace_vtime_active;
  36
  37                 switch (state) {
  38                 case DTRACE_VTIME_INACTIVE:
  39                         nstate = DTRACE_VTIME_ACTIVE;
  40                         break;
  41
  42                 case DTRACE_VTIME_INACTIVE_TNF:
  43                         nstate = DTRACE_VTIME_ACTIVE_TNF;
  44                         break;
  45
  46                 case DTRACE_VTIME_ACTIVE:
  47                 case DTRACE_VTIME_ACTIVE_TNF:
  48                         panic("DTrace virtual time already enabled");
  49                         /*NOTREACHED*/
  50                 }
  51
  52         } while (dtrace_cas32((uint32_t *)&dtrace_vtime_active,
  53             state, nstate) != state);
  54 }
  55
  56 void
  57 dtrace_vtime_disable(void)
  58 {
  59         dtrace_vtime_state_t state, nstate = 0;
  60
  61         do {
  62                 state = dtrace_vtime_active;
  63
  64                 switch (state) {
  65                 case DTRACE_VTIME_ACTIVE:
  66                         nstate = DTRACE_VTIME_INACTIVE;
  67                         break;
  68
  69                 case DTRACE_VTIME_ACTIVE_TNF:
  70                         nstate = DTRACE_VTIME_INACTIVE_TNF;
  71                         break;
  72
  73                 case DTRACE_VTIME_INACTIVE:
  74                 case DTRACE_VTIME_INACTIVE_TNF:
  75                         panic("DTrace virtual time already disabled");
  76                         /*NOTREACHED*/
  77                 }
  78
  79         } while (dtrace_cas32((uint32_t *)&dtrace_vtime_active,
  80             state, nstate) != state);
  81 }
  82
  83 void
  84 dtrace_vtime_switch(kthread_t *next)
  85 {
  86         dtrace_icookie_t cookie;
  87         hrtime_t ts;
  88
  89         cookie = dtrace_interrupt_disable();
  90         ts = dtrace_gethrtime();
  91
  92         if (curthread->t_dtrace_start != 0) {
  93                 curthread->t_dtrace_vtime += ts - curthread->t_dtrace_start;
  94                 curthread->t_dtrace_start = 0;
  95         }
  96
  97         if (next != NULL)
  98                 next->t_dtrace_start = ts;
  99
 100         dtrace_interrupt_enable(cookie);
 101 }