[PATCH 3/6] VM: Split out the accounting of unstable writes from BDI_RECLAIMABLE

Trond Myklebust
2010-01-06T20:59:32Z

From: Peter Zijlstra <peterz@infradead.org>

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Jan Kara <jack@suse.cz>
---

fs/nfs/write.c | 6 +++---
include/linux/backing-dev.h | 3 ++-
mm/backing-dev.c | 6 ++++--
mm/filemap.c | 2 +-
mm/page-writeback.c | 16 ++++++++++------
mm/truncate.c | 2 +-
6 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index ee3daf4..978de7f 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -440,7 +440,7 @@ nfs_mark_request_commit(struct nfs_page *req)
NFS_PAGE_TAG_COMMIT);
spin_unlock(&inode->i_lock);
inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
- inc_bdi_stat(req->wb_page->mapping->backing_dev_info, BDI_RECLAIMABLE);
+ inc_bdi_stat(req->wb_page->mapping->backing_dev_info, BDI_UNSTABLE);
mark_inode_unstable_pages(inode);
}

@@ -451,7 +451,7 @@ nfs_clear_request_commit(struct nfs_page *req)

if (test_and_clear_bit(PG_CLEAN, &(req)->wb_flags)) {
dec_zone_page_state(page, NR_UNSTABLE_NFS);
- dec_bdi_stat(page->mapping->backing_dev_info, BDI_RECLAIMABLE);
+ dec_bdi_stat(page->mapping->backing_dev_info, BDI_UNSTABLE);
return 1;
}
return 0;
@@ -1322,7 +1322,7 @@ nfs_commit_list(struct inode *inode, struct list_head *head, int how)
nfs_mark_request_commit(req);
dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
dec_bdi_stat(req->wb_page->mapping->backing_dev_info,
- BDI_RECLAIMABLE);
+ BDI_UNSTABLE);
nfs_clear_page_tag_locked(req);
}
return -ENOMEM;
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index fcbc26a..42c3e2a 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -36,7 +36,8 @@ enum bdi_state {
typedef int (congested_fn)(void *, int);

enum bdi_stat_item {
- BDI_RECLAIMABLE,
+ BDI_DIRTY,
+ BDI_UNSTABLE,
BDI_WRITEBACK,
NR_BDI_STAT_ITEMS
};
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 0e8ca03..88f3655 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -88,7 +88,8 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v)
#define K(x) ((x) << (PAGE_SHIFT - 10))
seq_printf(m,
"BdiWriteback: %8lu kB\n"
- "BdiReclaimable: %8lu kB\n"
+ "BdiDirty: %8lu kB\n"
+ "BdiUnstable: %8lu kB\n"
"BdiDirtyThresh: %8lu kB\n"
"DirtyThresh: %8lu kB\n"
"BackgroundThresh: %8lu kB\n"
@@ -102,7 +103,8 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v)
"wb_list: %8u\n"
"wb_cnt: %8u\n",
(unsigned long) K(bdi_stat(bdi, BDI_WRITEBACK)),
- (unsigned long) K(bdi_stat(bdi, BDI_RECLAIMABLE)),
+ (unsigned long) K(bdi_stat(bdi, BDI_DIRTY)),
+ (unsigned long) K(bdi_stat(bdi, BDI_UNSTABLE)),
K(bdi_thresh), K(dirty_thresh),
K(background_thresh), nr_wb, nr_dirty, nr_io, nr_more_io,
!list_empty(&bdi->bdi_list), bdi->state, bdi->wb_mask,
diff --git a/mm/filemap.c b/mm/filemap.c
index 96ac6b0..458387d 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -136,7 +136,7 @@ void __remove_from_page_cache(struct page *page)
*/
if (PageDirty(page) && mapping_cap_account_dirty(mapping)) {
dec_zone_page_state(page, NR_FILE_DIRTY);
- dec_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
+ dec_bdi_stat(mapping->backing_dev_info, BDI_DIRTY);
}
}

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index ede5356..aa26b0f 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -272,7 +272,8 @@ static void clip_bdi_dirty_limit(struct backing_dev_info *bdi,
else
avail_dirty = 0;

- avail_dirty += bdi_stat(bdi, BDI_RECLAIMABLE) +
+ avail_dirty += bdi_stat(bdi, BDI_DIRTY) +
+ bdi_stat(bdi, BDI_UNSTABLE) +
bdi_stat(bdi, BDI_WRITEBACK);

*pbdi_dirty = min(*pbdi_dirty, avail_dirty);
@@ -511,7 +512,8 @@ static void balance_dirty_pages(struct address_space *mapping,
nr_unstable_nfs;
nr_writeback = global_page_state(NR_WRITEBACK);

- bdi_nr_reclaimable = bdi_stat(bdi, BDI_RECLAIMABLE);
+ bdi_nr_reclaimable = bdi_stat(bdi, BDI_DIRTY) +
+ bdi_stat(bdi, BDI_UNSTABLE);
bdi_nr_writeback = bdi_stat(bdi, BDI_WRITEBACK);

if (bdi_nr_reclaimable + bdi_nr_writeback <= bdi_thresh)
@@ -561,10 +563,12 @@ static void balance_dirty_pages(struct address_space *mapping,
* deltas.
*/
if (bdi_thresh < 2*bdi_stat_error(bdi)) {
- bdi_nr_reclaimable = bdi_stat_sum(bdi, BDI_RECLAIMABLE);
+ bdi_nr_reclaimable = bdi_stat_sum(bdi, BDI_DIRTY) +
+ bdi_stat_sum(bdi, BDI_UNSTABLE);
bdi_nr_writeback = bdi_stat_sum(bdi, BDI_WRITEBACK);
} else if (bdi_nr_reclaimable) {
- bdi_nr_reclaimable = bdi_stat(bdi, BDI_RECLAIMABLE);
+ bdi_nr_reclaimable = bdi_stat(bdi, BDI_DIRTY) +
+ bdi_stat(bdi, BDI_UNSTABLE);
bdi_nr_writeback = bdi_stat(bdi, BDI_WRITEBACK);
}

@@ -1086,7 +1090,7 @@ void account_page_dirtied(struct page *page, struct address_space *mapping)
{
if (mapping_cap_account_dirty(mapping)) {
__inc_zone_page_state(page, NR_FILE_DIRTY);
- __inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
+ __inc_bdi_stat(mapping->backing_dev_info, BDI_DIRTY);
task_dirty_inc(current);
task_io_account_write(PAGE_CACHE_SIZE);
}
@@ -1262,7 +1266,7 @@ int clear_page_dirty_for_io(struct page *page)
if (TestClearPageDirty(page)) {
dec_zone_page_state(page, NR_FILE_DIRTY);
dec_bdi_stat(mapping->backing_dev_info,
- BDI_RECLAIMABLE);
+ BDI_DIRTY);
return 1;
}
return 0;
diff --git a/mm/truncate.c b/mm/truncate.c
index 342deee..b0ce8fb 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -75,7 +75,7 @@ void cancel_dirty_page(struct page *page, unsigned int account_size)
if (mapping && mapping_cap_account_dirty(mapping)) {
dec_zone_page_state(page, NR_FILE_DIRTY);
dec_bdi_stat(mapping->backing_dev_info,
- BDI_RECLAIMABLE);
+ BDI_DIRTY);
if (account_size)
task_io_account_cancelled_write(account_size);
}