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-rw-r--r--arch/i386/kernel/syscall_table.S2
-rw-r--r--arch/ia64/kernel/entry.S2
-rw-r--r--include/asm-i386/unistd.h2
-rw-r--r--include/asm-ia64/unistd.h1
-rw-r--r--include/linux/mmzone.h6
-rw-r--r--include/linux/swap.h1
-rw-r--r--kernel/sys_ni.c1
-rw-r--r--mm/page_alloc.c33
-rw-r--r--mm/vmscan.c64
9 files changed, 104 insertions, 8 deletions
diff --git a/arch/i386/kernel/syscall_table.S b/arch/i386/kernel/syscall_table.S
index 6cd1ed311f02..d408afaf6495 100644
--- a/arch/i386/kernel/syscall_table.S
+++ b/arch/i386/kernel/syscall_table.S
@@ -251,7 +251,7 @@ ENTRY(sys_call_table)
.long sys_io_submit
.long sys_io_cancel
.long sys_fadvise64 /* 250 */
- .long sys_ni_syscall
+ .long sys_set_zone_reclaim
.long sys_exit_group
.long sys_lookup_dcookie
.long sys_epoll_create
diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index d99316c9be28..b1d5d3d5276c 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -1579,7 +1579,7 @@ sys_call_table:
data8 sys_keyctl
data8 sys_ni_syscall
data8 sys_ni_syscall // 1275
- data8 sys_ni_syscall
+ data8 sys_set_zone_reclaim
data8 sys_ni_syscall
data8 sys_ni_syscall
data8 sys_ni_syscall
diff --git a/include/asm-i386/unistd.h b/include/asm-i386/unistd.h
index 61bcc1b1e3f4..176413fb9ae3 100644
--- a/include/asm-i386/unistd.h
+++ b/include/asm-i386/unistd.h
@@ -256,7 +256,7 @@
#define __NR_io_submit 248
#define __NR_io_cancel 249
#define __NR_fadvise64 250
-
+#define __NR_set_zone_reclaim 251
#define __NR_exit_group 252
#define __NR_lookup_dcookie 253
#define __NR_epoll_create 254
diff --git a/include/asm-ia64/unistd.h b/include/asm-ia64/unistd.h
index 33e26c557c5c..f7f43ec2483a 100644
--- a/include/asm-ia64/unistd.h
+++ b/include/asm-ia64/unistd.h
@@ -263,6 +263,7 @@
#define __NR_add_key 1271
#define __NR_request_key 1272
#define __NR_keyctl 1273
+#define __NR_set_zone_reclaim 1276
#ifdef __KERNEL__
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index beacd931b606..dfc2452ccb10 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -145,6 +145,12 @@ struct zone {
int all_unreclaimable; /* All pages pinned */
/*
+ * Does the allocator try to reclaim pages from the zone as soon
+ * as it fails a watermark_ok() in __alloc_pages?
+ */
+ int reclaim_pages;
+
+ /*
* prev_priority holds the scanning priority for this zone. It is
* defined as the scanning priority at which we achieved our reclaim
* target at the previous try_to_free_pages() or balance_pgdat()
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 3bbc41be9bd0..0d21e682d99d 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -173,6 +173,7 @@ extern void swap_setup(void);
/* linux/mm/vmscan.c */
extern int try_to_free_pages(struct zone **, unsigned int, unsigned int);
+extern int zone_reclaim(struct zone *, unsigned int, unsigned int);
extern int shrink_all_memory(int);
extern int vm_swappiness;
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 0dda70ed1f98..6f15bea7d1a8 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -77,6 +77,7 @@ cond_syscall(sys_request_key);
cond_syscall(sys_keyctl);
cond_syscall(compat_sys_keyctl);
cond_syscall(compat_sys_socketcall);
+cond_syscall(sys_set_zone_reclaim);
/* arch-specific weak syscall entries */
cond_syscall(sys_pciconfig_read);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 40169f0b7e9e..3c0f69ded6b5 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -724,6 +724,14 @@ int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
return 1;
}
+static inline int
+should_reclaim_zone(struct zone *z, unsigned int gfp_mask)
+{
+ if (!z->reclaim_pages)
+ return 0;
+ return 1;
+}
+
/*
* This is the 'heart' of the zoned buddy allocator.
*/
@@ -760,17 +768,32 @@ __alloc_pages(unsigned int __nocast gfp_mask, unsigned int order,
classzone_idx = zone_idx(zones[0]);
- restart:
+restart:
/* Go through the zonelist once, looking for a zone with enough free */
for (i = 0; (z = zones[i]) != NULL; i++) {
-
- if (!zone_watermark_ok(z, order, z->pages_low,
- classzone_idx, 0, 0))
- continue;
+ int do_reclaim = should_reclaim_zone(z, gfp_mask);
if (!cpuset_zone_allowed(z))
continue;
+ /*
+ * If the zone is to attempt early page reclaim then this loop
+ * will try to reclaim pages and check the watermark a second
+ * time before giving up and falling back to the next zone.
+ */
+zone_reclaim_retry:
+ if (!zone_watermark_ok(z, order, z->pages_low,
+ classzone_idx, 0, 0)) {
+ if (!do_reclaim)
+ continue;
+ else {
+ zone_reclaim(z, gfp_mask, order);
+ /* Only try reclaim once */
+ do_reclaim = 0;
+ goto zone_reclaim_retry;
+ }
+ }
+
page = buffered_rmqueue(z, order, gfp_mask);
if (page)
goto got_pg;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 6379ddbffd9b..7da846960d8a 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1323,3 +1323,67 @@ static int __init kswapd_init(void)
}
module_init(kswapd_init)
+
+
+/*
+ * Try to free up some pages from this zone through reclaim.
+ */
+int zone_reclaim(struct zone *zone, unsigned int gfp_mask, unsigned int order)
+{
+ struct scan_control sc;
+ int nr_pages = 1 << order;
+ int total_reclaimed = 0;
+
+ /* The reclaim may sleep, so don't do it if sleep isn't allowed */
+ if (!(gfp_mask & __GFP_WAIT))
+ return 0;
+ if (zone->all_unreclaimable)
+ return 0;
+
+ sc.gfp_mask = gfp_mask;
+ sc.may_writepage = 0;
+ sc.may_swap = 0;
+ sc.nr_mapped = read_page_state(nr_mapped);
+ sc.nr_scanned = 0;
+ sc.nr_reclaimed = 0;
+ /* scan at the highest priority */
+ sc.priority = 0;
+
+ if (nr_pages > SWAP_CLUSTER_MAX)
+ sc.swap_cluster_max = nr_pages;
+ else
+ sc.swap_cluster_max = SWAP_CLUSTER_MAX;
+
+ shrink_zone(zone, &sc);
+ total_reclaimed = sc.nr_reclaimed;
+
+ return total_reclaimed;
+}
+
+asmlinkage long sys_set_zone_reclaim(unsigned int node, unsigned int zone,
+ unsigned int state)
+{
+ struct zone *z;
+ int i;
+
+ if (node >= MAX_NUMNODES || !node_online(node))
+ return -EINVAL;
+
+ /* This will break if we ever add more zones */
+ if (!(zone & (1<<ZONE_DMA|1<<ZONE_NORMAL|1<<ZONE_HIGHMEM)))
+ return -EINVAL;
+
+ for (i = 0; i < MAX_NR_ZONES; i++) {
+ if (!(zone & 1<<i))
+ continue;
+
+ z = &NODE_DATA(node)->node_zones[i];
+
+ if (state)
+ z->reclaim_pages = 1;
+ else
+ z->reclaim_pages = 0;
+ }
+
+ return 0;
+}
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