LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Rik van Riel <riel@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
	Lee Schermerhorn <Lee.Schermerhorn@hp.com>,
	linux-mm@kvack.org, Lee Schermerhorn <lee.schermerhorn@hp.com>
Subject: [patch 05/21] define page_file_cache() function
Date: Thu, 28 Feb 2008 14:29:13 -0500	[thread overview]
Message-ID: <20080228192928.335536700@redhat.com> (raw)
In-Reply-To: <20080228192908.126720629@redhat.com>

[-- Attachment #1: rvr-01-linux-2.6-page_file_cache.patch --]
[-- Type: text/plain, Size: 6996 bytes --]

Define page_file_cache() function to answer the question:
	is page backed by a file?

Originally part of Rik van Riel's split-lru patch.  Extracted
to make available for other, independent reclaim patches.

Moved inline function to linux/mm_inline.h where it will
be needed by subsequent "split LRU" and "noreclaim" patches.  

Unfortunately this needs to use a page flag, since the
PG_swapbacked state needs to be preserved all the way
to the point where the page is last removed from the
LRU.  Trying to derive the status from other info in
the page resulted in wrong VM statistics in earlier
split VM patchsets.


Signed-off-by:  Rik van Riel <riel@redhat.com>
Signed-off-by:  Lee Schermerhorn <lee.schermerhorn@hp.com>


Index: linux-2.6.25-rc2-mm1/include/linux/mm_inline.h
===================================================================
--- linux-2.6.25-rc2-mm1.orig/include/linux/mm_inline.h	2008-02-26 21:29:50.000000000 -0500
+++ linux-2.6.25-rc2-mm1/include/linux/mm_inline.h	2008-02-27 14:36:57.000000000 -0500
@@ -1,3 +1,24 @@
+#ifndef LINUX_MM_INLINE_H
+#define LINUX_MM_INLINE_H
+
+/**
+ * page_file_cache(@page)
+ * Returns !0 if @page is page cache page backed by a regular filesystem,
+ * or 0 if @page is anonymous, tmpfs or otherwise ram or swap backed.
+ *
+ * We would like to get this info without a page flag, but the state
+ * needs to survive until the page is last deleted from the LRU, which
+ * could be as far down as __page_cache_release.
+ */
+static inline int page_file_cache(struct page *page)
+{
+	if (PageSwapBacked(page))
+		return 0;
+
+	/* The page is page cache backed by a normal filesystem. */
+	return 2;
+}
+
 static inline void
 add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list l)
 {
@@ -49,3 +70,4 @@ del_page_from_lru(struct zone *zone, str
 	__dec_zone_state(zone, NR_INACTIVE + l);
 }
 
+#endif
Index: linux-2.6.25-rc2-mm1/mm/shmem.c
===================================================================
--- linux-2.6.25-rc2-mm1.orig/mm/shmem.c	2008-02-19 16:23:09.000000000 -0500
+++ linux-2.6.25-rc2-mm1/mm/shmem.c	2008-02-27 14:36:57.000000000 -0500
@@ -1434,6 +1434,7 @@ repeat:
 				goto failed;
 			}
 
+			SetPageSwapBacked(filepage);
 			spin_lock(&info->lock);
 			entry = shmem_swp_alloc(info, idx, sgp);
 			if (IS_ERR(entry))
Index: linux-2.6.25-rc2-mm1/include/linux/page-flags.h
===================================================================
--- linux-2.6.25-rc2-mm1.orig/include/linux/page-flags.h	2008-02-19 16:23:08.000000000 -0500
+++ linux-2.6.25-rc2-mm1/include/linux/page-flags.h	2008-02-27 14:36:57.000000000 -0500
@@ -89,6 +89,7 @@
 #define PG_mappedtodisk		16	/* Has blocks allocated on-disk */
 #define PG_reclaim		17	/* To be reclaimed asap */
 #define PG_buddy		19	/* Page is free, on buddy lists */
+#define PG_swapbacked		20	/* Page is backed by RAM/swap */
 
 /* PG_readahead is only used for file reads; PG_reclaim is only for writes */
 #define PG_readahead		PG_reclaim /* Reminder to do async read-ahead */
@@ -252,6 +253,10 @@ static inline void SetPageUptodate(struc
 #define ClearPageReclaim(page)	clear_bit(PG_reclaim, &(page)->flags)
 #define TestClearPageReclaim(page) test_and_clear_bit(PG_reclaim, &(page)->flags)
 
+#define PageSwapBacked(page)	test_bit(PG_swapbacked, &(page)->flags)
+#define SetPageSwapBacked(page)	set_bit(PG_swapbacked, &(page)->flags)
+#define __ClearPageSwapBacked(page)	__clear_bit(PG_swapbacked, &(page)->flags)
+
 #define PageCompound(page)	test_bit(PG_compound, &(page)->flags)
 #define __SetPageCompound(page)	__set_bit(PG_compound, &(page)->flags)
 #define __ClearPageCompound(page) __clear_bit(PG_compound, &(page)->flags)
Index: linux-2.6.25-rc2-mm1/mm/memory.c
===================================================================
--- linux-2.6.25-rc2-mm1.orig/mm/memory.c	2008-02-19 16:23:16.000000000 -0500
+++ linux-2.6.25-rc2-mm1/mm/memory.c	2008-02-27 14:36:57.000000000 -0500
@@ -1677,6 +1677,7 @@ gotten:
 		ptep_clear_flush(vma, address, page_table);
 		set_pte_at(mm, address, page_table, entry);
 		update_mmu_cache(vma, address, entry);
+		SetPageSwapBacked(new_page);
 		lru_cache_add_active(new_page);
 		page_add_new_anon_rmap(new_page, vma, address);
 
@@ -2148,6 +2149,7 @@ static int do_anonymous_page(struct mm_s
 	if (!pte_none(*page_table))
 		goto release;
 	inc_mm_counter(mm, anon_rss);
+	SetPageSwapBacked(page);
 	lru_cache_add_active(page);
 	page_add_new_anon_rmap(page, vma, address);
 	set_pte_at(mm, address, page_table, entry);
@@ -2291,6 +2293,7 @@ static int __do_fault(struct mm_struct *
 		set_pte_at(mm, address, page_table, entry);
 		if (anon) {
                         inc_mm_counter(mm, anon_rss);
+			SetPageSwapBacked(page);
                         lru_cache_add_active(page);
                         page_add_new_anon_rmap(page, vma, address);
 		} else {
Index: linux-2.6.25-rc2-mm1/mm/swap_state.c
===================================================================
--- linux-2.6.25-rc2-mm1.orig/mm/swap_state.c	2008-02-19 16:23:09.000000000 -0500
+++ linux-2.6.25-rc2-mm1/mm/swap_state.c	2008-02-27 14:36:57.000000000 -0500
@@ -82,6 +82,7 @@ int add_to_swap_cache(struct page *page,
 		if (!error) {
 			page_cache_get(page);
 			SetPageSwapCache(page);
+			SetPageSwapBacked(page);
 			set_page_private(page, entry.val);
 			total_swapcache_pages++;
 			__inc_zone_page_state(page, NR_FILE_PAGES);
Index: linux-2.6.25-rc2-mm1/mm/migrate.c
===================================================================
--- linux-2.6.25-rc2-mm1.orig/mm/migrate.c	2008-02-27 14:24:23.000000000 -0500
+++ linux-2.6.25-rc2-mm1/mm/migrate.c	2008-02-27 14:36:57.000000000 -0500
@@ -537,6 +537,8 @@ static int move_to_new_page(struct page 
 	/* Prepare mapping for the new page.*/
 	newpage->index = page->index;
 	newpage->mapping = page->mapping;
+	if (PageSwapBacked(page))
+		SetPageSwapBacked(newpage);
 
 	mapping = page_mapping(page);
 	if (!mapping)
Index: linux-2.6.25-rc2-mm1/mm/page_alloc.c
===================================================================
--- linux-2.6.25-rc2-mm1.orig/mm/page_alloc.c	2008-02-26 21:24:23.000000000 -0500
+++ linux-2.6.25-rc2-mm1/mm/page_alloc.c	2008-02-27 14:36:57.000000000 -0500
@@ -253,6 +253,7 @@ static void bad_page(struct page *page)
 			1 << PG_slab    |
 			1 << PG_swapcache |
 			1 << PG_writeback |
+			1 << PG_swapbacked |
 			1 << PG_buddy );
 	set_page_count(page, 0);
 	reset_page_mapcount(page);
@@ -485,6 +486,8 @@ static inline int free_pages_check(struc
 		bad_page(page);
 	if (PageDirty(page))
 		__ClearPageDirty(page);
+	if (PageSwapBacked(page))
+		__ClearPageSwapBacked(page);
 	/*
 	 * For now, we report if PG_reserved was found set, but do not
 	 * clear it, and do not free the page.  But we shall soon need
@@ -631,6 +634,7 @@ static int prep_new_page(struct page *pa
 			1 << PG_swapcache |
 			1 << PG_writeback |
 			1 << PG_reserved |
+			1 << PG_swapbacked |
 			1 << PG_buddy ))))
 		bad_page(page);
 

-- 
All Rights Reversed


  parent reply	other threads:[~2008-02-28 19:42 UTC|newest]

Thread overview: 60+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-02-28 19:29 [patch 00/21] VM pageout scalability improvements Rik van Riel
2008-02-28 19:29 ` [patch 01/21] move isolate_lru_page() to vmscan.c Rik van Riel
2008-02-29  2:29   ` KOSAKI Motohiro
2008-02-29  2:41     ` Rik van Riel
2008-02-29  2:47       ` KOSAKI Motohiro
2008-02-28 19:29 ` [patch 02/21] Use an indexed array for LRU variables Rik van Riel
2008-02-29 16:03   ` Andy Whitcroft
2008-03-03 18:57     ` Rik van Riel
2008-02-28 19:29 ` [patch 03/21] use an array for the LRU pagevecs Rik van Riel
2008-02-29 15:40   ` Andy Whitcroft
2008-03-01  7:02     ` KOSAKI Motohiro
2008-03-04 11:04       ` KOSAKI Motohiro
2008-03-04 20:38         ` Rik van Riel
2008-03-05  1:38           ` KOSAKI Motohiro
2008-02-28 19:29 ` [patch 04/21] free swap space on swap-in/activation Rik van Riel
2008-02-28 20:05   ` Lee Schermerhorn
2008-02-28 20:20     ` Rik van Riel
2008-02-28 19:29 ` Rik van Riel [this message]
2008-02-29 11:53   ` [patch 05/21] define page_file_cache() function KOSAKI Motohiro
2008-02-28 19:29 ` [patch 06/21] split LRU lists into anon & file sets Rik van Riel
2008-03-01 12:13   ` KOSAKI Motohiro
2008-03-01 12:46   ` KOSAKI Motohiro
2008-02-28 19:29 ` [patch 07/21] SEQ replacement for anonymous pages Rik van Riel
2008-03-03 10:50   ` barrioskmc@gmail
2008-02-28 19:29 ` [patch 08/21] (NEW) add some sanity checks to get_scan_ratio Rik van Riel
2008-03-04 10:40   ` minchan Kim
2008-02-28 19:29 ` [patch 09/21] (NEW) improve reclaim balancing Rik van Riel
2008-03-01 13:35   ` KOSAKI Motohiro
2008-03-03 19:26     ` Rik van Riel
2008-02-28 19:29 ` [patch 10/21] add newly swapped in pages to the inactive list Rik van Riel
2008-02-28 19:29 ` [patch 11/21] (NEW) more aggressively use lumpy reclaim Rik van Riel
2008-03-02 10:35   ` KOSAKI Motohiro
2008-03-02 14:23     ` Rik van Riel
2008-02-28 19:29 ` [patch 12/21] No Reclaim LRU Infrastructure Rik van Riel
     [not found]   ` <44c63dc40802282058h67f7597bvb614575f06c62e2c@mail.gmail.com>
2008-02-29 14:48     ` Lee Schermerhorn
     [not found]       ` <44c63dc40803021904n5de681datba400e08079c152d@mail.gmail.com>
2008-03-03  3:06         ` minchan Kim
2008-03-03 18:46         ` Rik van Riel
2008-03-03 23:38           ` barrioskmc@gmail
2008-03-04  1:55             ` Rik van Riel
2008-03-04 10:46   ` KOSAKI Motohiro
2008-03-04 15:05     ` Lee Schermerhorn
2008-03-04 21:21       ` Rik van Riel
2008-03-05  1:42       ` KOSAKI Motohiro
2008-02-28 19:29 ` [patch 13/21] Non-reclaimable page statistics Rik van Riel
2008-02-28 19:29 ` [patch 14/21] scan noreclaim list for reclaimable pages Rik van Riel
2008-02-28 23:41   ` Randy Dunlap
2008-02-29 14:38     ` Lee Schermerhorn
2008-02-28 19:29 ` [patch 15/21] ramfs pages are non-reclaimable Rik van Riel
2008-02-28 19:29 ` [patch 16/21] SHM_LOCKED pages are nonreclaimable Rik van Riel
2008-02-28 19:29 ` [patch 17/21] non-reclaimable mlocked pages Rik van Riel
     [not found]   ` <44c63dc40802282055q508af6ccsb0e8ac3fb5e67d24@mail.gmail.com>
2008-02-29 14:47     ` Lee Schermerhorn
2008-02-28 19:29 ` [patch 18/21] mlock vma pages under mmap_sem held for read Rik van Riel
2008-02-28 19:29 ` [patch 19/21] handle mlocked pages during map/unmap and truncate Rik van Riel
2008-02-28 19:29 ` [patch 20/21] account mlocked pages Rik van Riel
2008-02-28 19:29 ` [patch 21/21] cull non-reclaimable anon pages from the LRU at fault time Rik van Riel
2008-02-28 20:19   ` Lee Schermerhorn
2008-02-28 22:27     ` Rik van Riel
2008-02-28 19:49 ` [patch 00/21] VM pageout scalability improvements Rik van Riel
2008-02-28 20:14 ` John Stoffel
2008-02-28 20:23   ` Rik van Riel

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20080228192928.335536700@redhat.com \
    --to=riel@redhat.com \
    --cc=Lee.Schermerhorn@hp.com \
    --cc=kosaki.motohiro@jp.fujitsu.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --subject='Re: [patch 05/21] define page_file_cache() function' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).