[PATCH 2/6] Introduce node_zonelist() for accessing the zonelist for a GFP mask

Mel Gorman
2007-09-28T14:24:23Z

This patch introduces a node_zonelist() helper function. It is used to lookup
the appropriate zonelist given a node and a GFP mask. The patch on its own is
a cleanup but it helps clarify parts of the one-zonelist-per-node patchset. If
necessary, it can be merged with the next patch in this set without problems.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
---

drivers/char/sysrq.c | 3 +--
fs/buffer.c | 6 +++---
include/linux/gfp.h | 19 +++++++++++++++++--
include/linux/mempolicy.h | 2 +-
mm/mempolicy.c | 6 +++---
mm/page_alloc.c | 3 +--
mm/slab.c | 3 +--
mm/slub.c | 3 +--
8 files changed, 28 insertions(+), 17 deletions(-)

diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.23-rc8-mm2-005_freepages_zonelist/drivers/char/sysrq.c linux-2.6.23-rc8-mm2-007_node_zonelist/drivers/char/sysrq.c
--- linux-2.6.23-rc8-mm2-005_freepages_zonelist/drivers/char/sysrq.c 2007-09-27 14:40:51.000000000 +0100
+++ linux-2.6.23-rc8-mm2-007_node_zonelist/drivers/char/sysrq.c 2007-09-28 15:48:55.000000000 +0100
@@ -271,8 +271,7 @@ static struct sysrq_key_op sysrq_term_op

static void moom_callback(struct work_struct *ignored)
{
- out_of_memory(&NODE_DATA(0)->node_zonelists[ZONE_NORMAL],
- GFP_KERNEL, 0);
+ out_of_memory(node_zonelist(0, GFP_KERNEL), GFP_KERNEL, 0);
}

static DECLARE_WORK(moom_work, moom_callback);
diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.23-rc8-mm2-005_freepages_zonelist/fs/buffer.c linux-2.6.23-rc8-mm2-007_node_zonelist/fs/buffer.c
--- linux-2.6.23-rc8-mm2-005_freepages_zonelist/fs/buffer.c 2007-09-27 14:41:01.000000000 +0100
+++ linux-2.6.23-rc8-mm2-007_node_zonelist/fs/buffer.c 2007-09-28 15:48:55.000000000 +0100
@@ -369,13 +369,13 @@ void invalidate_bdev(struct block_device
static void free_more_memory(void)
{
struct zone **zones;
- pg_data_t *pgdat;
+ int nid;

wakeup_pdflush(1024);
yield();

- for_each_online_pgdat(pgdat) {
- zones = pgdat->node_zonelists[gfp_zone(GFP_NOFS)].zones;
+ for_each_online_node(nid) {
+ zones = node_zonelist(nid, GFP_NOFS);
if (*zones)
try_to_free_pages(zones, 0, GFP_NOFS);
}
diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.23-rc8-mm2-005_freepages_zonelist/include/linux/gfp.h linux-2.6.23-rc8-mm2-007_node_zonelist/include/linux/gfp.h
--- linux-2.6.23-rc8-mm2-005_freepages_zonelist/include/linux/gfp.h 2007-09-27 14:41:05.000000000 +0100
+++ linux-2.6.23-rc8-mm2-007_node_zonelist/include/linux/gfp.h 2007-09-28 15:48:55.000000000 +0100
@@ -157,13 +157,29 @@ static inline gfp_t set_migrateflags(gfp
* virtual kernel addresses to the allocated page(s).
*/

+static inline enum zone_type gfp_zonelist(gfp_t flags)
+{
+ int base = 0;
+
+ if (NUMA_BUILD && (flags & __GFP_THISNODE))
+ base = 1;
+
+ return base;
+}
+
/*
* We get the zone list from the current node and the gfp_mask.
* This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
+ * There are two zonelists per node, one for all zones with memory and
+ * one containing just zones from the node the zonelist belongs to.
*
* For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
* optimized to &contig_page_data at compile-time.
*/
+static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
+{
+ return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
+}

#ifndef HAVE_ARCH_FREE_PAGE
static inline void arch_free_page(struct page *page, int order) { }
@@ -185,8 +201,7 @@ static inline struct page *alloc_pages_n
if (nid < 0)
nid = numa_node_id();

- return __alloc_pages(gfp_mask, order,
- NODE_DATA(nid)->node_zonelists + gfp_zone(gfp_mask));
+ return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
}

#ifdef CONFIG_NUMA
diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.23-rc8-mm2-005_freepages_zonelist/include/linux/mempolicy.h linux-2.6.23-rc8-mm2-007_node_zonelist/include/linux/mempolicy.h
--- linux-2.6.23-rc8-mm2-005_freepages_zonelist/include/linux/mempolicy.h 2007-09-27 14:41:05.000000000 +0100
+++ linux-2.6.23-rc8-mm2-007_node_zonelist/include/linux/mempolicy.h 2007-09-28 15:48:55.000000000 +0100
@@ -241,7 +241,7 @@ static inline void mpol_fix_fork_child_f
static inline struct zonelist *huge_zonelist(struct vm_area_struct *vma,
unsigned long addr, gfp_t gfp_flags, struct mempolicy **mpol)
{
- return NODE_DATA(0)->node_zonelists + gfp_zone(gfp_flags);
+ return node_zonelist(0, gfp_flags);
}

static inline int do_migrate_pages(struct mm_struct *mm,
diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.23-rc8-mm2-005_freepages_zonelist/mm/mempolicy.c linux-2.6.23-rc8-mm2-007_node_zonelist/mm/mempolicy.c
--- linux-2.6.23-rc8-mm2-005_freepages_zonelist/mm/mempolicy.c 2007-09-27 14:41:05.000000000 +0100
+++ linux-2.6.23-rc8-mm2-007_node_zonelist/mm/mempolicy.c 2007-09-28 15:48:55.000000000 +0100
@@ -1155,7 +1155,7 @@ static struct zonelist *zonelist_policy(
nd = 0;
BUG();
}
- return NODE_DATA(nd)->node_zonelists + gfp_zone(gfp);
+ return node_zonelist(nd, gfp);
}

/* Do dynamic interleaving for a process */
@@ -1269,7 +1269,7 @@ struct zonelist *huge_zonelist(struct vm

nid = interleave_nid(pol, vma, addr, HPAGE_SHIFT);
__mpol_free(pol); /* finished with pol */
- return NODE_DATA(nid)->node_zonelists + gfp_zone(gfp_flags);
+ return node_zonelist(nid, gfp_flags);
}

zl = zonelist_policy(GFP_HIGHUSER, pol);
@@ -1291,7 +1291,7 @@ static struct page *alloc_page_interleav
struct zonelist *zl;
struct page *page;

- zl = NODE_DATA(nid)->node_zonelists + gfp_zone(gfp);
+ zl = node_zonelist(nid, gfp);
page = __alloc_pages(gfp, order, zl);
if (page && page_zone(page) == zl->zones[0])
inc_zone_page_state(page, NUMA_INTERLEAVE_HIT);
diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.23-rc8-mm2-005_freepages_zonelist/mm/page_alloc.c linux-2.6.23-rc8-mm2-007_node_zonelist/mm/page_alloc.c
--- linux-2.6.23-rc8-mm2-005_freepages_zonelist/mm/page_alloc.c 2007-09-28 15:48:35.000000000 +0100
+++ linux-2.6.23-rc8-mm2-007_node_zonelist/mm/page_alloc.c 2007-09-28 15:48:55.000000000 +0100
@@ -1816,10 +1816,9 @@ EXPORT_SYMBOL(free_pages);
static unsigned int nr_free_zone_pages(int offset)
{
/* Just pick one node, since fallback list is circular */
- pg_data_t *pgdat = NODE_DATA(numa_node_id());
unsigned int sum = 0;

- struct zonelist *zonelist = pgdat->node_zonelists + offset;
+ struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
struct zone **zonep = zonelist->zones;
struct zone *zone;

diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.23-rc8-mm2-005_freepages_zonelist/mm/slab.c linux-2.6.23-rc8-mm2-007_node_zonelist/mm/slab.c
--- linux-2.6.23-rc8-mm2-005_freepages_zonelist/mm/slab.c 2007-09-27 14:41:05.000000000 +0100
+++ linux-2.6.23-rc8-mm2-007_node_zonelist/mm/slab.c 2007-09-28 15:48:55.000000000 +0100
@@ -3246,8 +3246,7 @@ static void *fallback_alloc(struct kmem_
if (flags & __GFP_THISNODE)
return NULL;

- zonelist = &NODE_DATA(slab_node(current->mempolicy))
- ->node_zonelists[gfp_zone(flags)];
+ zonelist = node_zonelist(slab_node(current->mempolicy), flags);
local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK);

retry:
diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.23-rc8-mm2-005_freepages_zonelist/mm/slub.c linux-2.6.23-rc8-mm2-007_node_zonelist/mm/slub.c
--- linux-2.6.23-rc8-mm2-005_freepages_zonelist/mm/slub.c 2007-09-27 14:41:05.000000000 +0100
+++ linux-2.6.23-rc8-mm2-007_node_zonelist/mm/slub.c 2007-09-28 15:48:55.000000000 +0100
@@ -1303,8 +1303,7 @@ static struct page *get_any_partial(stru
if (!s->defrag_ratio || get_cycles() % 1024 > s->defrag_ratio)
return NULL;

- zonelist = &NODE_DATA(slab_node(current->mempolicy))
- ->node_zonelists[gfp_zone(flags)];
+ zonelist = node_zonelist(slab_node(current->mempolicy), flags);
for (z = zonelist->zones; *z; z++) {
struct kmem_cache_node *n;