[PATCH 11/14] Conversion of nr_unstable to per zone counter

Christoph Lameter
2006-06-08T23:03:36Z

Conversion of nr_unstable to a per zone counter

Avoids looping over processor to establish writeback state.

This converts the last critical page state for the VM and therefore
GET_PAGE_STATE_LAST becomes invalid. The next patch is needed to
make the kernel compile again.

Signed-off-by: Christoph Lameter <clameter@sgi.com>

Index: linux-2.6.17-rc6-mm1/fs/fs-writeback.c
===================================================================
--- linux-2.6.17-rc6-mm1.orig/fs/fs-writeback.c 2006-06-08 15:46:37.440287688 -0700
+++ linux-2.6.17-rc6-mm1/fs/fs-writeback.c 2006-06-08 15:47:46.620574179 -0700
@@ -473,7 +473,7 @@ void sync_inodes_sb(struct super_block *
.range_end = LLONG_MAX,
};
unsigned long nr_dirty = global_page_state(NR_DIRTY);
- unsigned long nr_unstable = read_page_state(nr_unstable);
+ unsigned long nr_unstable = global_page_state(NR_UNSTABLE);

wbc.nr_to_write = nr_dirty + nr_unstable +
(inodes_stat.nr_inodes - inodes_stat.nr_unused) +
Index: linux-2.6.17-rc6-mm1/mm/page_alloc.c
===================================================================
--- linux-2.6.17-rc6-mm1.orig/mm/page_alloc.c 2006-06-08 15:46:56.905879204 -0700
+++ linux-2.6.17-rc6-mm1/mm/page_alloc.c 2006-06-08 15:47:46.622527183 -0700
@@ -629,7 +629,8 @@ static int rmqueue_bulk(struct zone *zon
}

char *vm_stat_item_descr[NR_STAT_ITEMS] = {
- "mapped", "pagecache", "slab", "pagetable", "dirty", "writeback"
+ "mapped", "pagecache", "slab", "pagetable", "dirty", "writeback",
+ "unstable"
};

/*
@@ -1810,7 +1811,7 @@ void show_free_areas(void)
inactive,
global_page_state(NR_DIRTY),
global_page_state(NR_WRITEBACK),
- ps.nr_unstable,
+ global_page_state(NR_UNSTABLE),
nr_free_pages(),
global_page_state(NR_SLAB),
global_page_state(NR_MAPPED),
@@ -2810,10 +2811,9 @@ static char *vmstat_text[] = {
"nr_page_table_pages",
"nr_dirty",
"nr_writeback",
-
- /* Page state */
"nr_unstable",

+ /* Page state */
"pgpgin",
"pgpgout",
"pswpin",
Index: linux-2.6.17-rc6-mm1/fs/nfs/write.c
===================================================================
--- linux-2.6.17-rc6-mm1.orig/fs/nfs/write.c 2006-06-08 15:46:37.445170199 -0700
+++ linux-2.6.17-rc6-mm1/fs/nfs/write.c 2006-06-08 15:47:46.624480187 -0700
@@ -525,7 +525,7 @@ nfs_mark_request_commit(struct nfs_page
nfs_list_add_request(req, &nfsi->commit);
nfsi->ncommit++;
spin_unlock(&nfsi->req_lock);
- inc_page_state(nr_unstable);
+ inc_zone_page_state(req->wb_page, NR_UNSTABLE);
mark_inode_dirty(inode);
}
#endif
@@ -1382,7 +1382,6 @@ static void nfs_commit_done(struct rpc_t
{
struct nfs_write_data *data = calldata;
struct nfs_page *req;
- int res = 0;

dprintk("NFS: %4d nfs_commit_done (status %d)\n",
task->tk_pid, task->tk_status);
@@ -1420,9 +1419,8 @@ static void nfs_commit_done(struct rpc_t
nfs_mark_request_dirty(req);
next:
nfs_clear_page_writeback(req);
- res++;
+ dec_zone_page_state(req->wb_page, NR_UNSTABLE);
}
- sub_page_state(nr_unstable,res);
}

static const struct rpc_call_ops nfs_commit_ops = {
Index: linux-2.6.17-rc6-mm1/include/linux/page-flags.h
===================================================================
--- linux-2.6.17-rc6-mm1.orig/include/linux/page-flags.h 2006-06-08 15:46:56.906855706 -0700
+++ linux-2.6.17-rc6-mm1/include/linux/page-flags.h 2006-06-08 15:47:46.624480187 -0700
@@ -119,8 +119,7 @@
* commented here.
*/
struct page_state {
- unsigned long nr_unstable; /* NFS unstable pages */
-#define GET_PAGE_STATE_LAST nr_unstable
+#define GET_PAGE_STATE_LAST xxx

/*
* The below are zeroed by get_page_state(). Use get_full_page_state()
Index: linux-2.6.17-rc6-mm1/mm/page-writeback.c
===================================================================
--- linux-2.6.17-rc6-mm1.orig/mm/page-writeback.c 2006-06-08 15:46:56.907832208 -0700
+++ linux-2.6.17-rc6-mm1/mm/page-writeback.c 2006-06-08 15:47:46.625456689 -0700
@@ -110,7 +110,7 @@ struct writeback_state
static void get_writeback_state(struct writeback_state *wbs)
{
wbs->nr_dirty = global_page_state(NR_DIRTY);
- wbs->nr_unstable = read_page_state(nr_unstable);
+ wbs->nr_unstable = global_page_state(NR_UNSTABLE);
wbs->nr_mapped = global_page_state(NR_MAPPED);
wbs->nr_writeback = global_page_state(NR_WRITEBACK);
}
Index: linux-2.6.17-rc6-mm1/include/linux/mmzone.h
===================================================================
--- linux-2.6.17-rc6-mm1.orig/include/linux/mmzone.h 2006-06-08 15:46:56.908808710 -0700
+++ linux-2.6.17-rc6-mm1/include/linux/mmzone.h 2006-06-08 15:47:46.626433191 -0700
@@ -54,6 +54,7 @@ enum zone_stat_item {
NR_PAGETABLE, /* used for pagetables */
NR_DIRTY,
NR_WRITEBACK,
+ NR_UNSTABLE, /* NFS unstable pages */
NR_STAT_ITEMS };

#ifdef CONFIG_SMP
Index: linux-2.6.17-rc6-mm1/drivers/base/node.c
===================================================================
--- linux-2.6.17-rc6-mm1.orig/drivers/base/node.c 2006-06-08 15:46:56.901973196 -0700
+++ linux-2.6.17-rc6-mm1/drivers/base/node.c 2006-06-08 15:47:46.627409693 -0700
@@ -66,6 +66,7 @@ static ssize_t node_read_meminfo(struct
"Node %d LowFree: %8lu kB\n"
"Node %d Dirty: %8lu kB\n"
"Node %d Writeback: %8lu kB\n"
+ "Node %d Unstable: %8lu kB\n"
"Node %d Mapped: %8lu kB\n"
"Node %d Pagecache: %8lu kB\n"
"Node %d Slab: %8lu kB\n",
@@ -80,6 +81,7 @@ static ssize_t node_read_meminfo(struct
nid, K(i.freeram - i.freehigh),
nid, K(nr[NR_DIRTY]),
nid, K(nr[NR_WRITEBACK]),
+ nid, K(nr[NR_UNSTABLE]),
nid, K(nr[NR_MAPPED]),
nid, K(nr[NR_PAGECACHE]),
nid, K(nr[NR_SLAB]));
Index: linux-2.6.17-rc6-mm1/mm/swap_prefetch.c
===================================================================
--- linux-2.6.17-rc6-mm1.orig/mm/swap_prefetch.c 2006-06-08 15:46:56.908808710 -0700
+++ linux-2.6.17-rc6-mm1/mm/swap_prefetch.c 2006-06-08 15:47:46.627409693 -0700
@@ -397,7 +397,8 @@ static int prefetch_suitable(void)
limit = global_page_state(NR_MAPPED) +
global_page_state(NR_SLAB) +
global_page_state(NR_DIRTY) +
- ps.nr_unstable + total_swapcache_pages;
+ global_page_state(NR_UNSTABLE) +
+ total_swapcache_pages;
if (limit > ns->prefetch_watermark) {
node_clear(node, sp_stat.prefetch_nodes);
continue;