void prune_dcache(int count) 
     { 
         spin_lock(&dcache_lock); 
         for (;;) { 
             struct dentry *dentry; 
             struct list_head *tmp; 
            
             tmp = dentry_unused.prev; 
             if (tmp == &dentry_unused) 
                 break; 
             list_del_init(tmp); 
             dentry = list_entry(tmp, struct dentry, d_lru); 
            
             /* If the dentry was recently referenced, don't free it. */ 
             if (dentry->d_vfs_flags & DCACHE_REFERENCED) { 
                 dentry->d_vfs_flags &= ~DCACHE_REFERENCED; 
                 list_add(&dentry->d_lru, &dentry_unused); 
                 continue; 
             } 
             dentry_stat.nr_unused--; 
     
             /* Unused dentry with a count? */ 
             if (atomic_read(&dentry->d_count)) 
                 BUG(); 
           
             prune_one_dentry(dentry); 
             if (!--count) 
                 break; 
          } 
          spin_unlock(&dcache_lock); 
       } 

     void prune_dcache(int count) 
     { 
          DEFINE_RESCHED_COUNT; 

     redo: 
          spin_lock(&dcache_lock); 
          for (;;) { 
              struct dentry *dentry; 
              struct list_head *tmp; 

              if (TEST_RESCHED_COUNT(100)) { 
                  RESET_RESCHED_COUNT(); 
                  if (conditional_schedule_needed()) { 
                     spin_unlock(&dcache_lock); 
                     unconditional_schedule(); 
                     goto redo; 
                  } 
              } 
         
              tmp = dentry_unused.prev; 
           
              if (tmp == &dentry_unused) 
                  break; 
              list_del_init(tmp); 
              dentry = list_entry(tmp, struct dentry, d_lru); 
      
              /* If the dentry was recently referenced, don't free it. */ 
              if (dentry->d_vfs_flags & DCACHE_REFERENCED) { 
                  dentry->d_vfs_flags &= ~DCACHE_REFERENCED; 
                  list_add(&dentry->d_lru, &dentry_unused); 
                  continue; 
              } 
              dentry_stat.nr_unused--; 
         
              /* Unused dentry with a count? */ 
              if (atomic_read(&dentry->d_count)) 
                  BUG(); 
          
              prune_one_dentry(dentry); 
              if (!--count) 
                  break; 
          } 
          spin_unlock(&dcache_lock); 
      }