lkml.org 
[lkml]   [1999]   [May]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
Subjectmem_map bitmaps ?
I'm reading linux source code, and confused by bitmap size of mem_map.
In free_area_init() ( init.c , kernel 2.0.35 )
...
for ( i = 0; i < NR_MEM_LISTS; i++ ) {
unsigned long bitmap_size ;
init_mem_queue(free_area+i) ;
mask+=mask ;
end_mem = (end_mem + ~mask) &mask ;
bitmap_size = (end_mem - PAGE_OFFSET) >> (PAGE_SHIFT+i) ;
???????????????
bitmap_size = (bitmap_size+7) >> 3 ;
...
}
on bit of free_area[i].map represent 2^(i+1) pages, so I think the line
with ????
should be:
bitmap_size = (end_mem - PAGE_OFFSET ) >> (PAGE_SHIFT+i+1) ;
I know I would be error, but can anybody explain it to me, thanks very
much !!!!!


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:51    [from the cache]
©2003-2011 Jasper Spaans