ra->cache_hit = 0; 
void handle_ra_miss(struct address_space *mapping,		struct file_ra_state *ra, pgoff_t offset){	ra->flags |= RA_FLAG_MISS;	ra->flags &= ~RA_FLAG_INCACHE;}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/3b30bbd963ac2606b0377b39c9d148d6eeef7dce/readahead.c/clean/mm/readahead.c