mem-hotplug: avoid multiple zones sharing same boot strapping boot_pageset
For each new populated zone of hotadded node, need to update its pagesets
with dynamically allocated per_cpu_pageset struct for all possible CPUs:
1) Detach zone->pageset from the shared boot_pageset
at end of __build_all_zonelists().
2) Use mutex to protect zone->pageset when it's still
shared in onlined_pages()
Otherwises, multiple zones of different nodes would share same boot strapping
boot_pageset for same CPU, which will finally cause below kernel panic:
------------[ cut here ]------------
kernel BUG at mm/page_alloc.c:1239!
invalid opcode: 0000 [#1] SMP
...
Call Trace:
[<ffffffff811300c1>] __alloc_pages_nodemask+0x131/0x7b0
[<ffffffff81162e67>] alloc_pages_current+0x87/0xd0
[<ffffffff81128407>] __page_cache_alloc+0x67/0x70
[<ffffffff811325f0>] __do_page_cache_readahead+0x120/0x260
[<ffffffff81132751>] ra_submit+0x21/0x30
[<ffffffff811329c6>] ondemand_readahead+0x166/0x2c0
[<ffffffff81132ba0>] page_cache_async_readahead+0x80/0xa0
[<ffffffff8112a0e4>] generic_file_aio_read+0x364/0x670
[<ffffffff81266cfa>] nfs_file_read+0xca/0x130
[<ffffffff8117b20a>] do_sync_read+0xfa/0x140
[<ffffffff8117bf75>] vfs_read+0xb5/0x1a0
[<ffffffff8117c151>] sys_read+0x51/0x80
[<ffffffff8103c032>] system_call_fastpath+0x16/0x1b
RIP [<ffffffff8112ff13>] get_page_from_freelist+0x883/0x900
RSP <ffff88000d1e78a8>
---[ end trace 4bda28328b9990db ]
[akpm@linux-foundation.org: merge fix]
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: Andi Kleen <andi.kleen@intel.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index f6f2c50..a367ed5 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -652,7 +652,7 @@
void get_zone_counts(unsigned long *active, unsigned long *inactive,
unsigned long *free);
-void build_all_zonelists(void);
+void build_all_zonelists(void *data);
void wakeup_kswapd(struct zone *zone, int order);
int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
int classzone_idx, int alloc_flags);
diff --git a/init/main.c b/init/main.c
index 22881b5..3bdb152 100644
--- a/init/main.c
+++ b/init/main.c
@@ -567,7 +567,7 @@
setup_per_cpu_areas();
smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
- build_all_zonelists();
+ build_all_zonelists(NULL);
page_alloc_init();
printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line);
diff --git a/kernel/cpu.c b/kernel/cpu.c
index a3fbcc0..3e8b3ba 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -358,7 +358,7 @@
}
if (pgdat->node_zonelists->_zonerefs->zone == NULL)
- build_all_zonelists();
+ build_all_zonelists(NULL);
#endif
cpu_maps_update_begin();
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 85eb4d3..089cc97 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -389,6 +389,11 @@
int nid;
int ret;
struct memory_notify arg;
+ /*
+ * mutex to protect zone->pageset when it's still shared
+ * in onlined_pages()
+ */
+ static DEFINE_MUTEX(zone_pageset_mutex);
arg.start_pfn = pfn;
arg.nr_pages = nr_pages;
@@ -415,12 +420,14 @@
* This means the page allocator ignores this zone.
* So, zonelist must be updated after online.
*/
+ mutex_lock(&zone_pageset_mutex);
if (!populated_zone(zone))
need_zonelists_rebuild = 1;
ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
online_pages_range);
if (ret) {
+ mutex_unlock(&zone_pageset_mutex);
printk(KERN_DEBUG "online_pages %lx at %lx failed\n",
nr_pages, pfn);
memory_notify(MEM_CANCEL_ONLINE, &arg);
@@ -429,8 +436,12 @@
zone->present_pages += onlined_pages;
zone->zone_pgdat->node_present_pages += onlined_pages;
+ if (need_zonelists_rebuild)
+ build_all_zonelists(zone);
+ else
+ zone_pcp_update(zone);
- zone_pcp_update(zone);
+ mutex_unlock(&zone_pageset_mutex);
setup_per_zone_wmarks();
calculate_zone_inactive_ratio(zone);
if (onlined_pages) {
@@ -438,10 +449,7 @@
node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
}
- if (need_zonelists_rebuild)
- build_all_zonelists();
- else
- vm_total_pages = nr_free_pagecache_pages();
+ vm_total_pages = nr_free_pagecache_pages();
writeback_set_ratelimit();
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 595d0ac..21c52d2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2572,7 +2572,7 @@
NUMA_ZONELIST_ORDER_LEN);
user_zonelist_order = oldval;
} else if (oldval != user_zonelist_order)
- build_all_zonelists();
+ build_all_zonelists(NULL);
}
out:
mutex_unlock(&zl_order_mutex);
@@ -2922,9 +2922,10 @@
*/
static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
+static void setup_zone_pageset(struct zone *zone);
/* return values int ....just for stop_machine() */
-static int __build_all_zonelists(void *dummy)
+static __init_refok int __build_all_zonelists(void *data)
{
int nid;
int cpu;
@@ -2939,6 +2940,14 @@
build_zonelist_cache(pgdat);
}
+#ifdef CONFIG_MEMORY_HOTPLUG
+ /* Setup real pagesets for the new zone */
+ if (data) {
+ struct zone *zone = data;
+ setup_zone_pageset(zone);
+ }
+#endif
+
/*
* Initialize the boot_pagesets that are going to be used
* for bootstrapping processors. The real pagesets for
@@ -2958,7 +2967,7 @@
return 0;
}
-void build_all_zonelists(void)
+void build_all_zonelists(void *data)
{
set_zonelist_order();
@@ -2969,7 +2978,7 @@
} else {
/* we have to stop all cpus to guarantee there is no user
of zonelist */
- stop_machine(__build_all_zonelists, NULL, NULL);
+ stop_machine(__build_all_zonelists, data, NULL);
/* cpuset refresh routine should be here */
}
vm_total_pages = nr_free_pagecache_pages();