[PATCH] how to fix shmdr for POLLING? [was: Re: PSIM and MP tests -- anybody got working?]

[Joel Sherrill]

Karel Gardas wrote:

> On Mon, 23 Jan 2006, Joel Sherrill wrote:
>
>> I was afraid of this.  shmdr has not been used with new execption model
>> and assumes it can "wrap" the clock tick driver ISR.  It was written 
>> before
>> the Timer Manager exists.  Instead of its clock tick ISR trick, it 
>> should install
>> an RTEMS timer to run once a tick when polled.
>
>
> If I understand this well, then the code should looks like in diff 
> below, but the problem is that then Shm_Poll seems to be run too often 
> (just my idea), since I usually end with consumed amount of 
> instructions/time... Even if I go with 1000 clicks, it's still the 
> same, but test at least runs some functionality. I guess my task setup 
> is wrong...
>
Each click is an instruction in the simulator so the clicks per tick 
must be relatively high to
allow for positive movement in the test.

Do you have a functional gdb?

Can you dump the shm?

> Do you have any idea how to fix this?
>
Only if I could peek inside with gdb. :)

FWIW I think your idea of moving to a polling task is better than using 
a Timer.
There is already an MPCI task in RTEMS waiting for requests so when this 
is working it would be even better to let him poll directly.  That would 
eliminate overhead.

> Thanks,
> Karel
> -- 
> Karel Gardas                  kgardas at objectsecurity.com
> ObjectSecurity Ltd.           http://www.objectsecurity.com
>
> Index: Makefile.am
> ===================================================================
> RCS file: /usr1/CVS/rtems/c/src/libchip/Makefile.am,v
> retrieving revision 1.36
> diff -u -r1.36 Makefile.am
> --- Makefile.am    12 Jan 2006 10:12:31 -0000    1.36
> +++ Makefile.am    23 Jan 2006 22:59:35 -0000
> @@ -96,7 +96,7 @@
>  shmdr_rel_SOURCES = shmdr/addlq.c shmdr/cnvpkt.c shmdr/getlq.c 
> shmdr/dump.c \
>      shmdr/fatal.c shmdr/getpkt.c shmdr/init.c shmdr/initlq.c 
> shmdr/intr.c \
>      shmdr/mpisr.c shmdr/poll.c shmdr/receive.c shmdr/retpkt.c 
> shmdr/send.c \
> -    shmdr/setckvec.c
> +    shmdr/poller.c
>  shmdr_rel_CPPFLAGS = $(AM_CPPFLAGS)
>  shmdr_rel_LDFLAGS = $(RTEMS_RELLDFLAGS)
>  endif
> Index: shmdr/init.c
> ===================================================================
> RCS file: /usr1/CVS/rtems/c/src/libchip/shmdr/init.c,v
> retrieving revision 1.16
> diff -u -r1.16 init.c
> --- shmdr/init.c    20 Apr 2004 10:43:39 -0000    1.16
> +++ shmdr/init.c    23 Jan 2006 22:59:36 -0000
> @@ -20,6 +20,7 @@
>  #define _SHM_INIT
>
>  #include <rtems.h>
> +#include <rtems/rtems/tasks.h>
>  #include <shm_driver.h>
>
>  #include <string.h>    /* memset() */
> @@ -126,8 +127,21 @@
>    interrupt_value   = Shm_Convert( Shm_Configuration->Intr.value );
>    interrupt_cause   = Shm_Convert( Shm_Configuration->Intr.length );
>
> -  if ( Shm_Configuration->poll_intr == POLLED_MODE ) Shm_setclockvec();
> -  else                                               Shm_setvec();
> +  if ( Shm_Configuration->poll_intr == POLLED_MODE ) {
> +    rtems_name task_name;
> +    rtems_id tid;
> +    rtems_status_code status;
> +
> +    task_name = rtems_build_name( 'P', 'S', 'H', 'M' );
> +    status = rtems_task_create( task_name,
> +                                1,
> +                                RTEMS_MINIMUM_STACK_SIZE,
> +                                RTEMS_NO_TIMESLICE | RTEMS_NO_ASR | 
> RTEMS_INTERRUPT_LEVEL(0),
> +                                RTEMS_NO_FLOATING_POINT | RTEMS_LOCAL,
> +                                &tid );
> +    status = rtems_task_start( tid, Shm_Poller_task, 0 );
> +  }
> +  else Shm_setvec();
>
>    if ( Shm_Is_master_node() ) {
>
> Index: shmdr/poll.c
> ===================================================================
> RCS file: /usr1/CVS/rtems/c/src/libchip/shmdr/poll.c,v
> retrieving revision 1.15
> diff -u -r1.15 poll.c
> --- shmdr/poll.c    20 Apr 2004 10:43:39 -0000    1.15
> +++ shmdr/poll.c    23 Jan 2006 22:59:36 -0000
> @@ -27,12 +27,6 @@
>  void Shm_Poll()
>  {
>    uint32_t   tmpfront;
> -  rtems_libio_ioctl_args_t args;
> -
> -  /* invoke clock isr */
> -  args.iop = 0;
> -  args.command = rtems_build_name('I', 'S', 'R', ' ');
> -  (void) rtems_io_control(rtems_clock_major, rtems_clock_minor, &args);
>
>    /*
>     * Check for msgs only if we are "up"
> Index: shmdr/shm_driver.h
> ===================================================================
> RCS file: /usr1/CVS/rtems/c/src/libchip/shmdr/shm_driver.h,v
> retrieving revision 1.25
> diff -u -r1.25 shm_driver.h
> --- shmdr/shm_driver.h    29 Sep 2004 20:36:20 -0000    1.25
> +++ shmdr/shm_driver.h    23 Jan 2006 22:59:38 -0000
> @@ -479,8 +479,9 @@
>  void           Shm_Print_statistics( void );
>  void           MPCI_Fatal( Internal_errors_Source, boolean, uint32_t);
>  rtems_task     Shm_Cause_interrupt( uint32_t);
> +rtems_task     Shm_Poller_task( rtems_task_argument unused );
>  void           Shm_Poll();
> -void           Shm_setclockvec();
> +/* void           Shm_setclockvec(); */
>  void           Shm_Convert_packet( rtems_packet_prefix * );
>
>  /* CPU specific routines are inlined in shmcpu.h */
> --- /dev/null    2005-04-30 23:10:27.000000000 +0200
> +++ shmdr/poller.c    2006-01-23 23:49:08.000000000 +0100
> @@ -0,0 +1,33 @@
> +/*  Shm_Poller_task
> + *
> + *  This routine serves as a Shm_Poller task. It just calls Shm_Poll
> + *  every tick.
> + *
> + *  Input parameters:  NONE
> + *
> + *  Output parameters:  NONE
> + *
> + *  COPYRIGHT (c) 1989-1999.
> + *  On-Line Applications Research Corporation (OAR).
> + *
> + *  The license and distribution terms for this file may be
> + *  found in the file LICENSE in this distribution or at
> + *  http://www.rtems.com/license/LICENSE.
> + *
> + *  $Id: $
> + */
> +
> +#include <rtems.h>
> +#include <rtems/libio.h>
> +
> +#include "shm_driver.h"
> +
> +rtems_task Shm_Poller_task(
> +  rtems_task_argument unused
> +)
> +{
> +  for ( ; ; ) {
> +    rtems_task_wake_after( 1 );
> +    Shm_Poll();
> +  }
> +}