sys/platform/pc64/amd64/ktr.c

   1 /*
   2  * Copyright (c) 2005 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sys/platform/pc64/amd64/ktr.c,v 1.2 2007/09/24 03:24:45 yanyh Exp $
  35  */
  36 /*
  37  * Kernel tracepoint facility.
  38  */
  39
  40 #include "opt_ddb.h"
  41 #include "opt_ktr.h"
  42
  43 #include <sys/param.h>
  44 #include <sys/cons.h>
  45 #include <sys/kernel.h>
  46 #include <sys/libkern.h>
  47 #include <sys/proc.h>
  48 #include <sys/sysctl.h>
  49 #include <sys/ktr.h>
  50
  51 /*
  52  * This routine fills in the ktr_caller1 and ktr_caller2 fields by
  53  * tracing back through the kernel stack to locate the stack frames
  54  * and return addresses.
  55  *
  56  *
  57  *      [first argument]
  58  *      [retpc]
  59  *      [frameptr]              -> points to caller's frame pointer
  60  * sp ->[junk]
  61  */
  62
  63 static __inline
  64 void **
  65 FRAMEUP(void **frameptr)
  66 {
  67     void **newframeptr;
  68
  69     newframeptr = (void **)frameptr[0];
  70     if (((uintptr_t)newframeptr ^ (uintptr_t)frameptr) & ~16383)
  71         newframeptr = frameptr;
  72     return(newframeptr);
  73 }
  74
  75 void
  76 cpu_ktr_caller(struct ktr_entry *_ktr)
  77 {
  78     struct ktr_entry *ktr;
  79     void **frameptr;
  80
  81     frameptr = (void **)&_ktr - 2;      /* frame, retpc to ktr_log */
  82     ktr = _ktr;
  83     frameptr = FRAMEUP(frameptr);       /* frame, retpc to traced function */
  84     frameptr = FRAMEUP(frameptr);       /* frame, caller1 of traced function */
  85     ktr->ktr_caller1 = frameptr[1];
  86     frameptr = FRAMEUP(frameptr);       /* frame, caller2 of caller1 */
  87     ktr->ktr_caller2 = frameptr[1];
  88 }
  89