Checkpointing Problem!

Chittari Prasanna Kumar BE prasanna at krec.ernet.in
Thu Nov 30 02:39:15 EST 2000


hi,
  i am working on the project similar to Epckpt but with a concept of 
loadable module. here i have a problem in handling the page requests.

when i checkpoint a process in which malloc is used i found that if i 
malloc 1mb and make sure that all pages are used ( are present in
memory by making use of some loop in user program, i have written small
code is down ) before i checkpointed then there is no problem ,otherwise
its pmd_none is > 0 that's there is no valid pmd for it. i think i cannot
call handle_mm_fault ( or some thing like make_pages_present of mm.h,memory.c)
to bring the brk segment pages into memory because of invalid page tables!

In Epckpt he was in kernel and found it to be ok! but as i am working
as char driver i didn't get the same.

For this reason i am unable to get through it, can any one help me out.

thanks for replying.

Chittari Prasanna Kumar
KREC, Surathkal.
India.


int main()
{
  int *p,i;
  p=(int *)malloc(SIZE*sizeof(int));

#if USE
 for(i=0 ; i< SIZE; i++)
   p[i]=i;
#endif
  :
  :
 
  now checkpoint here
   fails if USE is not >= 1
  
 :
 :
}




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