Eric Lee / linux-smarc-t335x-v3.2

Download as
Browse Code ยป

Commit b7abea9630bc8ffc663a751e46680db25c4cdf8d

Authored by KAMEZAWA Hiroyuki
Committed by Linus Torvalds
1 parent 073e587ec2
Exists in master and in 4 other branches v3.2_AM335xPSP_04.06.00.11, v3.2_NEWT335xPSP_04.06.00.11, v3.2_SBC_SMARTMEN, v3.2_SMARCT335xPSP_04.06.00.11

memcg: make page->mapping NULL before uncharge 

This patch tries to make page->mapping to be NULL before
mem_cgroup_uncharge_cache_page() is called.

"page->mapping == NULL" is a good check for "whether the page is still
radix-tree or not".  This patch also adds BUG_ON() to
mem_cgroup_uncharge_cache_page();

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Showing 3 changed files with 9 additions and 3 deletions Side-by-side Diff

... ... @@ -116,12 +116,12 @@
116 116 {
117 117 struct address_space *mapping = page->mapping;
118 118  
119   - mem_cgroup_uncharge_cache_page(page);
120 119 radix_tree_delete(&mapping->page_tree, page->index);
121 120 page->mapping = NULL;
122 121 mapping->nrpages--;
123 122 __dec_zone_page_state(page, NR_FILE_PAGES);
124 123 BUG_ON(page_mapped(page));
  124 + mem_cgroup_uncharge_cache_page(page);
125 125  
126 126 /*
127 127 * Some filesystems seem to re-dirty the page even after
... ... @@ -734,6 +734,7 @@
734 734 void mem_cgroup_uncharge_cache_page(struct page *page)
735 735 {
736 736 VM_BUG_ON(page_mapped(page));
  737 + VM_BUG_ON(page->mapping);
737 738 __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE);
738 739 }
739 740  
... ... @@ -330,8 +330,6 @@
330 330 __inc_zone_page_state(newpage, NR_FILE_PAGES);
331 331  
332 332 spin_unlock_irq(&mapping->tree_lock);
333   - if (!PageSwapCache(newpage))
334   - mem_cgroup_uncharge_cache_page(page);
335 333  
336 334 return 0;
337 335 }
... ... @@ -341,6 +339,8 @@
341 339 */
342 340 static void migrate_page_copy(struct page *newpage, struct page *page)
343 341 {
  342 + int anon;
  343 +
344 344 copy_highpage(newpage, page);
345 345  
346 346 if (PageError(page))
347 347  
... ... @@ -378,7 +378,12 @@
378 378 #endif
379 379 ClearPagePrivate(page);
380 380 set_page_private(page, 0);
  381 + /* page->mapping contains a flag for PageAnon() */
  382 + anon = PageAnon(page);
381 383 page->mapping = NULL;
  384 +
  385 + if (!anon) /* This page was removed from radix-tree. */
  386 + mem_cgroup_uncharge_cache_page(page);
382 387  
383 388 /*
384 389 * If any waiters have accumulated on the new page then