src/kern/freebsd/events.hh

   1 /*
   2  * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
   3  * All rights reserved.
   4  *
   5  * This software was developed by the University of Cambridge Computer
   6  * Laboratory as part of the CTSRD Project, with support from the UK Higher
   7  * Education Innovation Fund (HEIF).
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions are
  11  * met: redistributions of source code must retain the above copyright
  12  * notice, this list of conditions and the following disclaimer;
  13  * redistributions in binary form must reproduce the above copyright
  14  * notice, this list of conditions and the following disclaimer in the
  15  * documentation and/or other materials provided with the distribution;
  16  * neither the name of the copyright holders nor the names of its
  17  * contributors may be used to endorse or promote products derived from
  18  * this software without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  23  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  24  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  25  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  26  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  30  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 #ifndef __KERN_FREEBSD_EVENTS_HH__
  34 #define __KERN_FREEBSD_EVENTS_HH__
  35
  36 #include "kern/system_events.hh"
  37
  38 namespace FreeBSD {
  39
  40 /** A class to skip udelay() and related calls in the kernel.
  41  * This class has two additional parameters that take the argument to udelay and
  42  * manipulated it to come up with ns and eventually ticks to quiesce for.
  43  * See descriptions of argDivToNs and argMultToNs below.
  44  */
  45 class UDelayEvent : public SkipFuncEvent
  46 {
  47   private:
  48     /** value to divide arg by to create ns. This is present beacues the linux
  49      * kernel code sometime precomputes the first multiply that is done in
  50      * udelay() if the parameter is a constant. We need to undo it so here is
  51      * how. */
  52     uint64_t argDivToNs;
  53
  54     /** value to multiple arg by to create ns. Nominally, this is 1000 to
  55      * convert us to ns, but since linux can do some preprocessing of constant
  56      * values something else might be required. */
  57     uint64_t argMultToNs;
  58
  59   public:
  60     UDelayEvent(PCEventQueue *q, const std::string &desc, Addr addr,
  61             uint64_t mult, uint64_t div)
  62         : SkipFuncEvent(q, desc, addr), argDivToNs(div), argMultToNs(mult) {}
  63     virtual void process(ThreadContext *xc);
  64 };
  65
  66 }
  67
  68 #endif