Detecting Tests Which Don't Have Enough Workspace

[Joel Sherrill]

On 3/12/2015 12:45 PM, Gedare Bloom wrote:
> On Thu, Mar 12, 2015 at 1:41 PM, Joel Sherrill
> <joel.sherrill at oarcorp.com> wrote:
>> Hi
>>
>> Many BSPs can link a test but don't actually have enough memory
>> to run the test. They will fail in the first few lines when the requested
>> memory for the RTEMS work area is not available. I hacked together
>> a script which adds together the code, data, bss, work space and
>> stack space requested. If this exceeds physical memory on the board,
>> then the test will fail.  It is possible to come close and still run out of
>> memory during initialization (e.g. malloc, etc) but this approach could
>> detect some tests which will fail by inspecting them on the host.
>>
>> This is a shell script but would be better built into the rtems-tools
>> and using the gdb/mi. Combined with information on the
>> available memory on the target, we could throw out some obvious
>> failure cases without touching hardware.
>>
>> Thoughts?
>>
> Would it be worthwhile to instrument our build (post-link) to do
> something like this?
I think it is worth doing something with this.   We need to know a few
things about a BSP to do this in the general case:

+ Is code loaded into RAM? If not, it doesn't need to be taken into account.
+ How much RAM is there?
+ In some cases, the program may not load at offset 0 of RAM and there
   could be a reserved area. One case is m68k BSPs which sometimes load
  at 0x3000 or 0x4000 to leave space for a ROM monitor.  We could ignore
  this factor and just take a hit when it is run.

But it definitely could avoid running some tests which are guaranteed to
fail.  Consider this output:

$ sh ../rtsize v850
./v850-rtems4.11/c/v850sim/testsuites/fstests/fsdos*/*.exe
216338
./v850-rtems4.11/c/v850sim/testsuites/fstests/fsdosfsformat01/fsdosfsformat01.exe
1259536
./v850-rtems4.11/c/v850sim/testsuites/fstests/fsdosfsname01/fsdosfsname01.exe

There is only 1MB RAM for the simulator. The second test is doomed. It
will not run. The first may run.

>> ===============================
>> #! /bin/sh
>>
>> if [ $# -le 2 ] ; then
>>   echo "Usage: $0 ARCH EXE ..."
>>   exit 1
>> fi
>>
>> ARCH=$1
>> shift
>>
>> target=${ARCH}-rtems4.11
>> type ${ARCH}-rtems4.11-size >/dev/null 2>&1
>> if [ $? -ne 0 ] ; then
>>   echo "${ARCH} does not appear to have RTEMS 4.11 tools installed"
>>   exit 1
>> fi
>>
>>
>> extract_size()
>> {
>>   ( echo "p Configuration.work_space_size" ; \
>>     echo "quit" ) | ${target}-gdb ${exe} 2>&1 | grep "\$1" | \
>>   cut -d'=' -f2
>> }
>>
>> for exe in $*
>> do
>>  image_size=`${target}-size ${exe} | tail -1 | cut -f4`
>>  wkspace_size=`extract_size Configuration.work_space_size`
>>  stackspace_size=`extract_size Configuration.stack_space_size`
>>
>>  #echo ${image_size} ${wkspace_size} ${stackspace_size}
>>
>>  total=`echo ${image_size} ${wkspace_size} + ${stackspace_size} + p | dc`
>>  echo ${total} ${exe}
>> done
>>
>> exit 0
>>
>> ===============================
>>
>> --
>> Joel Sherrill, Ph.D.             Director of Research & Development
>> joel.sherrill at OARcorp.com        On-Line Applications Research
>> Ask me about RTEMS: a free RTOS  Huntsville AL 35805
>> Support Available                (256) 722-9985
>>
>>
>> _______________________________________________
>> devel mailing list
>> devel at rtems.org
>> http://lists.rtems.org/mailman/listinfo/devel

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel.sherrill at OARcorp.com        On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
Support Available                (256) 722-9985