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mm: use two zonelist that are filtered by GFP mask 

Currently a node has two sets of zonelists, one for each zone type in the
system and a second set for GFP_THISNODE allocations.  Based on the zones
allowed by a gfp mask, one of these zonelists is selected.  All of these
zonelists consume memory and occupy cache lines.

This patch replaces the multiple zonelists per-node with two zonelists.  The
first contains all populated zones in the system, ordered by distance, for
fallback allocations when the target/preferred node has no free pages.  The
second contains all populated zones in the node suitable for GFP_THISNODE
allocations.

An iterator macro is introduced called for_each_zone_zonelist() that interates
through each zone allowed by the GFP flags in the selected zonelist.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mel Gorman 2008-04-28 02:12:16 -07:00 committed by Linus Torvalds
parent 18ea7e710d
commit 54a6eb5c47
10 changed files with 168 additions and 154 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
arch/parisc/mm/init.c
View File

@ -603,15 +603,18 @@ void show_mem(void)
#ifdef CONFIG_DISCONTIGMEM
{
struct zonelist *zl;
int i, j, k;
int i, j;
for (i = 0; i < npmem_ranges; i++) {
zl = node_zonelist(i);
for (j = 0; j < MAX_NR_ZONES; j++) {
zl = NODE_DATA(i)->node_zonelists + j;
struct zone **z;
struct zone *zone;
printk("Zone list for zone %d on node %d: ", j, i);
for (k = 0; zl->zones[k] != NULL; k++)
printk("[%d/%s] ", zone_to_nid(zl->zones[k]), zl->zones[k]->name);
for_each_zone_zonelist(zone, z, zl, j)
printk("[%d/%s] ", zone_to_nid(zone),
zone->name);
printk("\n");
}
}

10
fs/buffer.c
View File

@ -360,16 +360,18 @@ void invalidate_bdev(struct block_device *bdev)
*/
static void free_more_memory(void)
{
struct zonelist *zonelist;
struct zone **zones;
int nid;
wakeup_pdflush(1024);
yield();
for_each_online_node(nid) {
zonelist = node_zonelist(nid, GFP_NOFS);
if (zonelist->zones[0])
try_to_free_pages(zonelist, 0, GFP_NOFS);
zones = first_zones_zonelist(node_zonelist(nid, GFP_NOFS),
gfp_zone(GFP_NOFS));
if (*zones)
try_to_free_pages(node_zonelist(nid, GFP_NOFS), 0,
GFP_NOFS);
}
}

13
include/linux/gfp.h
View File

@ -151,17 +151,26 @@ static inline enum zone_type gfp_zone(gfp_t flags)
* virtual kernel addresses to the allocated page(s).
*/
static inline int gfp_zonelist(gfp_t flags)
{
if (NUMA_BUILD && unlikely(flags & __GFP_THISNODE))
return 1;
return 0;
}
/*
* 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 many zonelists per node, two for each active zone.
* 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_zone(flags);
return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
}
#ifndef HAVE_ARCH_FREE_PAGE

65
include/linux/mmzone.h
View File

@ -393,10 +393,10 @@ static inline int zone_is_oom_locked(const struct zone *zone)
* The NUMA zonelists are doubled becausse we need zonelists that restrict the
* allocations to a single node for GFP_THISNODE.
*
* [0 .. MAX_NR_ZONES -1] : Zonelists with fallback
* [MAZ_NR_ZONES ... MAZ_ZONELISTS -1] : No fallback (GFP_THISNODE)
* [0] : Zonelist with fallback
* [1] : No fallback (GFP_THISNODE)
*/
#define MAX_ZONELISTS (2 * MAX_NR_ZONES)
#define MAX_ZONELISTS 2
/*
@ -464,7 +464,7 @@ struct zonelist_cache {
unsigned long last_full_zap; /* when last zap'd (jiffies) */
};
#else
#define MAX_ZONELISTS MAX_NR_ZONES
#define MAX_ZONELISTS 1
struct zonelist_cache;
#endif
@ -486,24 +486,6 @@ struct zonelist {
#endif
};
#ifdef CONFIG_NUMA
/*
* Only custom zonelists like MPOL_BIND need to be filtered as part of
* policies. As described in the comment for struct zonelist_cache, these
* zonelists will not have a zlcache so zlcache_ptr will not be set. Use
* that to determine if the zonelists needs to be filtered or not.
*/
static inline int alloc_should_filter_zonelist(struct zonelist *zonelist)
{
return !zonelist->zlcache_ptr;
}
#else
static inline int alloc_should_filter_zonelist(struct zonelist *zonelist)
{
return 0;
}
#endif /* CONFIG_NUMA */
#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
struct node_active_region {
unsigned long start_pfn;
@ -731,6 +713,45 @@ extern struct zone *next_zone(struct zone *zone);
zone; \
zone = next_zone(zone))
/* Returns the first zone at or below highest_zoneidx in a zonelist */
static inline struct zone **first_zones_zonelist(struct zonelist *zonelist,
enum zone_type highest_zoneidx)
{
struct zone **z;
/* Find the first suitable zone to use for the allocation */
z = zonelist->zones;
while (*z && zone_idx(*z) > highest_zoneidx)
z++;
return z;
}
/* Returns the next zone at or below highest_zoneidx in a zonelist */
static inline struct zone **next_zones_zonelist(struct zone **z,
enum zone_type highest_zoneidx)
{
/* Find the next suitable zone to use for the allocation */
while (*z && zone_idx(*z) > highest_zoneidx)
z++;
return z;
}
/**
* for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
* @zone - The current zone in the iterator
* @z - The current pointer within zonelist->zones being iterated
* @zlist - The zonelist being iterated
* @highidx - The zone index of the highest zone to return
*
* This iterator iterates though all zones at or below a given zone index.
*/
#define for_each_zone_zonelist(zone, z, zlist, highidx) \
for (z = first_zones_zonelist(zlist, highidx), zone = *z++; \
zone; \
z = next_zones_zonelist(z, highidx), zone = *z++)
#ifdef CONFIG_SPARSEMEM
#include <asm/sparsemem.h>
#endif

8
mm/hugetlb.c
View File

@ -97,11 +97,11 @@ static struct page *dequeue_huge_page_vma(struct vm_area_struct *vma,
struct mempolicy *mpol;
struct zonelist *zonelist = huge_zonelist(vma, address,
htlb_alloc_mask, &mpol);
struct zone **z;
struct zone *zone, **z;
for (z = zonelist->zones; *z; z++) {
nid = zone_to_nid(*z);
if (cpuset_zone_allowed_softwall(*z, htlb_alloc_mask) &&
for_each_zone_zonelist(zone, z, zonelist, MAX_NR_ZONES - 1) {
nid = zone_to_nid(zone);
if (cpuset_zone_allowed_softwall(zone, htlb_alloc_mask) &&
!list_empty(&hugepage_freelists[nid])) {
page = list_entry(hugepage_freelists[nid].next,
struct page, lru);

8
mm/oom_kill.c
View File

@ -175,12 +175,14 @@ static inline enum oom_constraint constrained_alloc(struct zonelist *zonelist,
gfp_t gfp_mask)
{
#ifdef CONFIG_NUMA
struct zone *zone;
struct zone **z;
enum zone_type high_zoneidx = gfp_zone(gfp_mask);
nodemask_t nodes = node_states[N_HIGH_MEMORY];
for (z = zonelist->zones; *z; z++)
if (cpuset_zone_allowed_softwall(*z, gfp_mask))
node_clear(zone_to_nid(*z), nodes);
for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
if (cpuset_zone_allowed_softwall(zone, gfp_mask))
node_clear(zone_to_nid(zone), nodes);
else
return CONSTRAINT_CPUSET;

170
mm/page_alloc.c
View File

@ -1378,42 +1378,29 @@ static void zlc_mark_zone_full(struct zonelist *zonelist, struct zone **z)
*/
static struct page *
get_page_from_freelist(gfp_t gfp_mask, unsigned int order,
struct zonelist *zonelist, int alloc_flags)
struct zonelist *zonelist, int high_zoneidx, int alloc_flags)
{
struct zone **z;
struct page *page = NULL;
int classzone_idx = zone_idx(zonelist->zones[0]);
int classzone_idx;
struct zone *zone, *preferred_zone;
nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */
int zlc_active = 0; /* set if using zonelist_cache */
int did_zlc_setup = 0; /* just call zlc_setup() one time */
enum zone_type highest_zoneidx = -1; /* Gets set for policy zonelists */
z = first_zones_zonelist(zonelist, high_zoneidx);
classzone_idx = zone_idx(*z);
preferred_zone = *z;
zonelist_scan:
/*
* Scan zonelist, looking for a zone with enough free.
* See also cpuset_zone_allowed() comment in kernel/cpuset.c.
*/
z = zonelist->zones;
preferred_zone = *z;
do {
/*
* In NUMA, this could be a policy zonelist which contains
* zones that may not be allowed by the current gfp_mask.
* Check the zone is allowed by the current flags
*/
if (unlikely(alloc_should_filter_zonelist(zonelist))) {
if (highest_zoneidx == -1)
highest_zoneidx = gfp_zone(gfp_mask);
if (zone_idx(*z) > highest_zoneidx)
continue;
}
for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
if (NUMA_BUILD && zlc_active &&
!zlc_zone_worth_trying(zonelist, z, allowednodes))
continue;
zone = *z;
if ((alloc_flags & ALLOC_CPUSET) &&
!cpuset_zone_allowed_softwall(zone, gfp_mask))
goto try_next_zone;
@ -1447,7 +1434,7 @@ try_next_zone:
zlc_active = 1;
did_zlc_setup = 1;
}
} while (*(++z) != NULL);
}
if (unlikely(NUMA_BUILD && page == NULL && zlc_active)) {
/* Disable zlc cache for second zonelist scan */
@ -1465,6 +1452,7 @@ __alloc_pages(gfp_t gfp_mask, unsigned int order,
struct zonelist *zonelist)
{
const gfp_t wait = gfp_mask & __GFP_WAIT;
enum zone_type high_zoneidx = gfp_zone(gfp_mask);
struct zone **z;
struct page *page;
struct reclaim_state reclaim_state;
@ -1490,7 +1478,7 @@ restart:
}
page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, order,
zonelist, ALLOC_WMARK_LOW|ALLOC_CPUSET);
zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET);
if (page)
goto got_pg;
@ -1534,7 +1522,8 @@ restart:
* Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
* See also cpuset_zone_allowed() comment in kernel/cpuset.c.
*/
page = get_page_from_freelist(gfp_mask, order, zonelist, alloc_flags);
page = get_page_from_freelist(gfp_mask, order, zonelist,
high_zoneidx, alloc_flags);
if (page)
goto got_pg;
@ -1547,7 +1536,7 @@ rebalance:
nofail_alloc:
/* go through the zonelist yet again, ignoring mins */
page = get_page_from_freelist(gfp_mask, order,
zonelist, ALLOC_NO_WATERMARKS);
zonelist, high_zoneidx, ALLOC_NO_WATERMARKS);
if (page)
goto got_pg;
if (gfp_mask & __GFP_NOFAIL) {
@ -1582,7 +1571,7 @@ nofail_alloc:
if (likely(did_some_progress)) {
page = get_page_from_freelist(gfp_mask, order,
zonelist, alloc_flags);
zonelist, high_zoneidx, alloc_flags);
if (page)
goto got_pg;
} else if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) {
@ -1598,7 +1587,7 @@ nofail_alloc:
* under heavy pressure.
*/
page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, order,
zonelist, ALLOC_WMARK_HIGH|ALLOC_CPUSET);
zonelist, high_zoneidx, ALLOC_WMARK_HIGH|ALLOC_CPUSET);
if (page) {
clear_zonelist_oom(zonelist);
goto got_pg;
@ -1713,14 +1702,15 @@ EXPORT_SYMBOL(free_pages);
static unsigned int nr_free_zone_pages(int offset)
{
struct zone **z;
struct zone *zone;
/* Just pick one node, since fallback list is circular */
unsigned int sum = 0;
struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
struct zone **zonep = zonelist->zones;
struct zone *zone;
for (zone = *zonep++; zone; zone = *zonep++) {
for_each_zone_zonelist(zone, z, zonelist, offset) {
unsigned long size = zone->present_pages;
unsigned long high = zone->pages_high;
if (size > high)
@ -2078,17 +2068,15 @@ static int find_next_best_node(int node, nodemask_t *used_node_mask)
*/
static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
{
enum zone_type i;
int j;
struct zonelist *zonelist;
for (i = 0; i < MAX_NR_ZONES; i++) {
zonelist = pgdat->node_zonelists + i;
for (j = 0; zonelist->zones[j] != NULL; j++)
;
j = build_zonelists_node(NODE_DATA(node), zonelist, j, i);
zonelist->zones[j] = NULL;
}
zonelist = &pgdat->node_zonelists[0];
for (j = 0; zonelist->zones[j] != NULL; j++)
;
j = build_zonelists_node(NODE_DATA(node), zonelist, j,
MAX_NR_ZONES - 1);
zonelist->zones[j] = NULL;
}
/*
@ -2096,15 +2084,12 @@ static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
*/
static void build_thisnode_zonelists(pg_data_t *pgdat)
{
enum zone_type i;
int j;
struct zonelist *zonelist;
for (i = 0; i < MAX_NR_ZONES; i++) {
zonelist = pgdat->node_zonelists + MAX_NR_ZONES + i;
j = build_zonelists_node(pgdat, zonelist, 0, i);
zonelist->zones[j] = NULL;
}
zonelist = &pgdat->node_zonelists[1];
j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
zonelist->zones[j] = NULL;
}
/*
@ -2117,27 +2102,24 @@ static int node_order[MAX_NUMNODES];
static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes)
{
enum zone_type i;
int pos, j, node;
int zone_type; /* needs to be signed */
struct zone *z;
struct zonelist *zonelist;
for (i = 0; i < MAX_NR_ZONES; i++) {
zonelist = pgdat->node_zonelists + i;
pos = 0;
for (zone_type = i; zone_type >= 0; zone_type--) {
for (j = 0; j < nr_nodes; j++) {
node = node_order[j];
z = &NODE_DATA(node)->node_zones[zone_type];
if (populated_zone(z)) {
zonelist->zones[pos++] = z;
check_highest_zone(zone_type);
}
zonelist = &pgdat->node_zonelists[0];
pos = 0;
for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) {
for (j = 0; j < nr_nodes; j++) {
node = node_order[j];
z = &NODE_DATA(node)->node_zones[zone_type];
if (populated_zone(z)) {
zonelist->zones[pos++] = z;
check_highest_zone(zone_type);
}
}
zonelist->zones[pos] = NULL;
}
zonelist->zones[pos] = NULL;
}
static int default_zonelist_order(void)
@ -2264,19 +2246,15 @@ static void build_zonelists(pg_data_t *pgdat)
/* Construct the zonelist performance cache - see further mmzone.h */
static void build_zonelist_cache(pg_data_t *pgdat)
{
int i;
struct zonelist *zonelist;
struct zonelist_cache *zlc;
struct zone **z;
for (i = 0; i < MAX_NR_ZONES; i++) {
struct zonelist *zonelist;
struct zonelist_cache *zlc;
struct zone **z;
zonelist = pgdat->node_zonelists + i;
zonelist->zlcache_ptr = zlc = &zonelist->zlcache;
bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
for (z = zonelist->zones; *z; z++)
zlc->z_to_n[z - zonelist->zones] = zone_to_nid(*z);
}
zonelist = &pgdat->node_zonelists[0];
zonelist->zlcache_ptr = zlc = &zonelist->zlcache;
bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
for (z = zonelist->zones; *z; z++)
zlc->z_to_n[z - zonelist->zones] = zone_to_nid(*z);
}
@ -2290,45 +2268,43 @@ static void set_zonelist_order(void)
static void build_zonelists(pg_data_t *pgdat)
{
int node, local_node;
enum zone_type i,j;
enum zone_type j;
struct zonelist *zonelist;
local_node = pgdat->node_id;
for (i = 0; i < MAX_NR_ZONES; i++) {
struct zonelist *zonelist;
zonelist = pgdat->node_zonelists + i;
zonelist = &pgdat->node_zonelists[0];
j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
j = build_zonelists_node(pgdat, zonelist, 0, i);
/*
* Now we build the zonelist so that it contains the zones
* of all the other nodes.
* We don't want to pressure a particular node, so when
* building the zones for node N, we make sure that the
* zones coming right after the local ones are those from
* node N+1 (modulo N)
*/
for (node = local_node + 1; node < MAX_NUMNODES; node++) {
if (!node_online(node))
continue;
j = build_zonelists_node(NODE_DATA(node), zonelist, j, i);
}
for (node = 0; node < local_node; node++) {
if (!node_online(node))
continue;
j = build_zonelists_node(NODE_DATA(node), zonelist, j, i);
}
zonelist->zones[j] = NULL;
/*
* Now we build the zonelist so that it contains the zones
* of all the other nodes.
* We don't want to pressure a particular node, so when
* building the zones for node N, we make sure that the
* zones coming right after the local ones are those from
* node N+1 (modulo N)
*/
for (node = local_node + 1; node < MAX_NUMNODES; node++) {
if (!node_online(node))
continue;
j = build_zonelists_node(NODE_DATA(node), zonelist, j,
MAX_NR_ZONES - 1);
}
for (node = 0; node < local_node; node++) {
if (!node_online(node))
continue;
j = build_zonelists_node(NODE_DATA(node), zonelist, j,
MAX_NR_ZONES - 1);
}
zonelist->zones[j] = NULL;
}
/* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
static void build_zonelist_cache(pg_data_t *pgdat)
{
int i;
for (i = 0; i < MAX_NR_ZONES; i++)
pgdat->node_zonelists[i].zlcache_ptr = NULL;
pgdat->node_zonelists[0].zlcache_ptr = NULL;
pgdat->node_zonelists[1].zlcache_ptr = NULL;
}
#endif /* CONFIG_NUMA */

8
mm/slab.c
View File

@ -3243,6 +3243,8 @@ static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags)
struct zonelist *zonelist;
gfp_t local_flags;
struct zone **z;
struct zone *zone;
enum zone_type high_zoneidx = gfp_zone(flags);
void *obj = NULL;
int nid;
@ -3257,10 +3259,10 @@ retry:
* Look through allowed nodes for objects available
* from existing per node queues.
*/
for (z = zonelist->zones; *z && !obj; z++) {
nid = zone_to_nid(*z);
for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
nid = zone_to_nid(zone);
if (cpuset_zone_allowed_hardwall(*z, flags) &&
if (cpuset_zone_allowed_hardwall(zone, flags) &&
cache->nodelists[nid] &&
cache->nodelists[nid]->free_objects)
obj = ____cache_alloc_node(cache,

8
mm/slub.c
View File

@ -1285,6 +1285,8 @@ static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags)
#ifdef CONFIG_NUMA
struct zonelist *zonelist;
struct zone **z;
struct zone *zone;
enum zone_type high_zoneidx = gfp_zone(flags);
struct page *page;
/*
@ -1310,12 +1312,12 @@ static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags)
return NULL;
zonelist = node_zonelist(slab_node(current->mempolicy), flags);
for (z = zonelist->zones; *z; z++) {
for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
struct kmem_cache_node *n;
n = get_node(s, zone_to_nid(*z));
n = get_node(s, zone_to_nid(zone));
if (n && cpuset_zone_allowed_hardwall(*z, flags) &&
if (n && cpuset_zone_allowed_hardwall(zone, flags) &&
n->nr_partial > MIN_PARTIAL) {
page = get_partial_node(n);
if (page)

21
mm/vmscan.c
View File

@ -1249,15 +1249,13 @@ static unsigned long shrink_zone(int priority, struct zone *zone,
static unsigned long shrink_zones(int priority, struct zonelist *zonelist,
struct scan_control *sc)
{
enum zone_type high_zoneidx = gfp_zone(sc->gfp_mask);
unsigned long nr_reclaimed = 0;
struct zone **zones = zonelist->zones;
int i;
struct zone **z;
struct zone *zone;
sc->all_unreclaimable = 1;
for (i = 0; zones[i] != NULL; i++) {
struct zone *zone = zones[i];
for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
if (!populated_zone(zone))
continue;
/*
@ -1311,8 +1309,9 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
unsigned long nr_reclaimed = 0;
struct reclaim_state *reclaim_state = current->reclaim_state;
unsigned long lru_pages = 0;
struct zone **zones = zonelist->zones;
int i;
struct zone **z;
struct zone *zone;
enum zone_type high_zoneidx = gfp_zone(gfp_mask);
if (scan_global_lru(sc))
count_vm_event(ALLOCSTALL);
@ -1320,8 +1319,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
* mem_cgroup will not do shrink_slab.
*/
if (scan_global_lru(sc)) {
for (i = 0; zones[i] != NULL; i++) {
struct zone *zone = zones[i];
for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
if (!cpuset_zone_allowed_hardwall(zone, GFP_KERNEL))
continue;
@ -1385,8 +1383,7 @@ out:
priority = 0;
if (scan_global_lru(sc)) {
for (i = 0; zones[i] != NULL; i++) {
struct zone *zone = zones[i];
for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
if (!cpuset_zone_allowed_hardwall(zone, GFP_KERNEL))
continue;