trace_intr.c

TRACE的源代码,在LINUX调试程序要使用的.

/*  This file (trace_intr.c) was created by Ron Rechenmacher <[e-mail]> on
    June 5, 2000. "TERMS AND CONDITIONS" governing this file are in the README
    or COPYING file. If you do not have such a file, one can be obtained by
    contacting Ron or Fermi Lab in Batavia IL, 60510, phone: [phone].
*/
#define __TRACE_INTR_C_REV	"\
$RCSfile: trace_intr.c,v $(ppc)\
$Revision: 1.4 $\
$Date: 2002/03/12 14:36:39 $"

#include <linux/trace.h>	/* traceControl_sp */
#include <asm/trace_intr.h>	/* TRACE_VECTOR, BUILD_TRACE_INTERRUPT */

/*  NOTE: For some reason, if the definition is placed after the includes,
    the EXPORT_SYMBOL macro and /sbin/genksyms functionality does not work */
char *trace_intr_c_rev = __TRACE_INTR_C_REV __TRACE_H_REV __TRACE_PROCESSOR_H_REV __TRACE_INTR_H_REV;

#include <linux/time.h>		/* do_gettimeofday */
#include <asm/uaccess.h>        /* copy_from_user(to,from,n) */
#include <linux/ptrace.h>       /* struct pt_regs */


/******************************************************************************
 *   Ref. arch/ppc/kernel/head.S
 *       and
 *        arch/ppc/kernel/traps.c
 */

void
TraceException( struct pt_regs	*regs )
{
	char			msg[traceControl_sp->messageSize_bytes];
	struct
	{   int		lvl;
	    char	*msg;
#	    if TRACE_COMPILER_DOES_DYNAMIC_ARRAYS == 1
	    int		params[traceControl_sp->numberOfParameter_integers];
#	    else
	    int		params[TRACE_NUM_PARAMETER_INTS];
#	    endif
	}			kk;
	void			*usr_space_kk_ptr;
	void			*usr_space_time_ptr;
	int			tid;
	struct s_traceEntry     *ep;
	int                     ii, *ip;



    /*  Skip over trap insn.
	Ref arch/ppc/kernel/ppc-stub.c:handle_exception() */
    regs->nip += 4;

    usr_space_time_ptr = (void *)regs->gpr[0];
    tid                =         regs->gpr[5];
    usr_space_kk_ptr   = (void *)regs->gpr[6];

#   if 0
    printk("hello from kernel land****************************************\n");
    printk("kk=%p tid=%d\n", usr_space_kk_ptr, tid );
#   endif

    copy_from_user( &kk, usr_space_kk_ptr, sizeof(kk) );

    /* COPYING MESSAGE TWICE!!! NEED TO WORK ON THIS */
    copy_from_user( msg, kk.msg, traceControl_sp->messageSize_bytes );

    kk.msg = msg; /* over write with kernel address */


    /* NOW THE CODE IS VERY SIMILAR TO THE CODE IN:
       init/trace_queue.c:traceCircularQueuePut() (MAKE THIS CODE A MACRO??) */

    ep = (struct s_traceEntry *)traceCircularQueueIncrement();

    do_gettimeofday( &ep->time );

    TRACE_ENTRY_SPECIFIC( ep );
    ep->pid = current->pid;
    ep->cpu = smp_processor_id();

    ep->tid = tid;

    ep->lvl = kk.lvl;
    strncpy( &(ep->data[0]), kk.msg, traceControl_sp->messageSize_bytes );

    /*  may need to, depending upon alignment issues, add the restriction
        that messageSize_bytes must be a multiple if sizeof(int)
        see also trace_proc.c:XXX */
    ip = (int *)&(ep->data[traceControl_sp->messageSize_bytes]);
    for (ii=0; ii<traceControl_sp->numberOfParameter_integers; ii++)
        ip[ii] = kk.params[ii];



    copy_to_user( usr_space_time_ptr, &ep->time, sizeof(struct timeval) );
    return;
}   /* TraceException */



/******************************************************************************
 *  trace_interrupt_init
 *
 */

void
trace_interrupt_init( void )
{
    return;
}   /* trace_interrupt_init */



/* ######################################################################### */

/*  EXPORT_SYMTAB get defined on the compile line for OX_OBJS make file
    target */
#include <linux/module.h>	/* has module code - effects alignment! */

/* traceControl_sp export in kernel/ksyms.c */
EXPORT_SYMBOL( traceCircularQueuePut );

#ifdef MODULE
/*  gcc -O -Wall -DMODULE -D__KERNEL__ -D__SMP__ -c trace_intr.c
	OR
    gcc -O -Wall -DMODULE -D__KERNEL__ -D__SMP__ -c trace_intr.c \
-DMODVERSIONS -DEXPORT_SYMTAB \
-include /usr/src/linux/include/linux/modversions.h
*/

int
init_module( void )
{   printk( "init for trace_intr - configuring interrupt\n" );
    trace_interrupt_init();
    return (0);
}

void
cleanup_module( void )
{   printk( "nothing to cleanup for trace_intr\n" );
}

#endif /* MODULE */