[lc-checkins] CVS: linux/mm memory.c,1.27,1.28 vmscan.c,1.31,1.32

[Rodrigo S. de C. <rc...@us...>]

Update of /cvsroot/linuxcompressed/linux/mm
In directory usw-pr-cvs1:/tmp/cvs-serv5957/mm

Modified Files:
	memory.c vmscan.c 
Log Message:

- Fixed compilation error in buffer.c when compiling it without compressed
cache.

- Fixed oops caused when running fillmem due to a null pointer

- Fixed major/minor faults for compressed cache. Now we have correct data
about when we actually had to perform IO to service a page fault.

- Improved support for clean pages. Now the clean page is compressed and
right away freed in shrink_cache().

- When a pte in do_no_page() has write access to the page, it's already set
as dirty. So, in the same way done in do_swap_page(), we already remove the
its fragment from compressed cache since it will need to be compressed again
anyway.



Index: memory.c
===================================================================
RCS file: /cvsroot/linuxcompressed/linux/mm/memory.c,v
retrieving revision 1.27
retrieving revision 1.28
diff -C2 -r1.27 -r1.28
*** memory.c	28 Apr 2002 20:51:34 -0000	1.27
--- memory.c	2 May 2002 16:31:37 -0000	1.28
***************
*** 1135,1141 ****
  
  	if (!page) {
! 		comp_cache_fragment_t * fragment;			
! 		if (find_comp_page(&swapper_space, entry.val, &fragment))
  			swapin_readahead(entry);
  		page = read_swap_cache_async(entry);
  		if (!page) {
--- 1135,1145 ----
  
  	if (!page) {
! 		comp_cache_fragment_t * fragment;
! 		/* perform readahead only if the page is on disk */
! 		if (find_comp_page(&swapper_space, entry.val, &fragment)) {
  			swapin_readahead(entry);
+ 			/* major fault */
+ 			ret = 2;
+ 		}			
  		page = read_swap_cache_async(entry);
  		if (!page) {
***************
*** 1150,1156 ****
  			return retval;
  		}
- 
- 		/* Had to read the page from swap area: Major fault */
- 		ret = 2;
  	}
  
--- 1154,1157 ----
***************
*** 1262,1265 ****
--- 1263,1267 ----
  	struct page * new_page;
  	pte_t entry;
+ 	int ret = 2; /* usually major fault */
  
  	if (!vma->vm_ops || !vma->vm_ops->nopage)
***************
*** 1306,1311 ****
  		flush_icache_page(vma, new_page);
  		entry = mk_pte(new_page, vma->vm_page_prot);
! 		if (write_access)
  			entry = pte_mkwrite(pte_mkdirty(entry));
  		set_pte(page_table, entry);
  	} else {
--- 1308,1317 ----
  		flush_icache_page(vma, new_page);
  		entry = mk_pte(new_page, vma->vm_page_prot);
! 		if (PageCompCache(new_page))
! 			ret = 1;
! 		if (write_access) {
  			entry = pte_mkwrite(pte_mkdirty(entry));
+ 			flush_comp_cache(new_page);
+ 		}
  		set_pte(page_table, entry);
  	} else {
***************
*** 1319,1323 ****
  	update_mmu_cache(vma, address, entry);
  	spin_unlock(&mm->page_table_lock);
! 	return 2;	/* Major fault */
  }
  
--- 1325,1329 ----
  	update_mmu_cache(vma, address, entry);
  	spin_unlock(&mm->page_table_lock);
! 	return ret;
  }
  

Index: vmscan.c
===================================================================
RCS file: /cvsroot/linuxcompressed/linux/mm/vmscan.c,v
retrieving revision 1.31
retrieving revision 1.32
diff -C2 -r1.31 -r1.32
*** vmscan.c	28 Apr 2002 20:51:34 -0000	1.31
--- vmscan.c	2 May 2002 16:31:37 -0000	1.32
***************
*** 511,516 ****
  		/* compress it if it's a clean page that has not been
  		 * compressed in a previous iteration */
! 		if (compress_clean_page(page, gfp_mask))
  			continue;
  
  		/* point of no return */
--- 511,520 ----
  		/* compress it if it's a clean page that has not been
  		 * compressed in a previous iteration */
! 		if (compress_clean_page(page, gfp_mask)) {
! 			list_del(entry);
! 			list_add_tail(entry, &inactive_list);
! 			max_scan++;
  			continue;
+ 		}
  
  		/* point of no return */